Insomnia and short/long sleep duration increase the risk of AMI, but their interaction with each other or with chronotype is not well known. We investigated the prospective joint associations of any two of these sleep traits on risk of AMI. We included 302 456 and 31 091 participants without past AMI episodes from UK Biobank (UKBB; 2006–10) and the Trøndelag Health Study (HUNT2; 1995–97), respectively. A total of 6 833 and 2 540 incident AMIs were identified during an average 11.7 and 21.0 years follow-up, in UKBB and HUNT2, respectively. Compared to those who reported normal sleep duration (7–8 h) without insomnia symptoms, the Cox proportional hazard ratios (HRs) for incident AMI in UKBB among participants who reported normal, short and long sleep duration with insomnia symptoms were 1.07 (95% CI 0.99, 1.15), 1.16 (95% CI 1.07, 1.25) and 1.40 (95% CI 1.21, 1.63), respectively. The corresponding HRs in HUNT2 were 1.09 (95% CI 0.95, 1.25), 1.17 (95% CI 0.87, 1.58) and 1.02 (95% CI 0.85, 1.23). The HRs for incident AMI in UKBB among evening chronotypes were 1.19 (95% CI 1.10, 1.29) for those who had insomnia symptoms, 1.18 (95% CI 1.08, 1.29) for those with short sleep duration, and 1.21 (95% CI 1.07, 1.37) for those with long sleep duration, compared to morning chronotypes without another sleep symptom. The relative excess risk for incident AMI in UKBB due to interaction between insomnia symptoms and long sleep duration was 0.25 (95% CI 0.01, 0.48). Insomnia symptoms with long sleep duration may contribute more than just an additive effect of these sleep traits on the risk of AMI.
Breast cancer is highly prevalent yet a more complete understanding of the interplay between genes and probable environmental risk factors, such as night work, remains lagging. Using a discordant twin pair design, we examined the association between night shift work and breast cancer risk, controlling for familial confounding. Shift work pattern was prospectively assessed by mailed questionnaires among 5,781 female twins from the Older Finnish Twin Cohort. Over the study period (1990–2018), 407 incident breast cancer cases were recorded using the Finnish Cancer Registry. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) adjusting for potential confounders. Within-pair co-twin analyses were employed in 57 pairs to account for potential familial confounding. Compared to women who worked days only, women with shift work that included night shifts had a 1.58-fold higher risk of breast cancer (HR = 1.58; 95%CI, 1.16–2.15, highest among the youngest women i.e. born 1950–1957, HR = 2.08; 95%CI, 1.32–3.28), whereas 2-shift workers not including night shifts, did not (HR = 0.84; 95%CI, 0.59–1.21). Women with longer sleep (average sleep duration > 8 h/night) appeared at greatest risk of breast cancer if they worked night shifts (HR = 2.91; 95%CI, 1.55–5.46; Pintx=0.32). Results did not vary by chronotype (Pintx=0.74). Co-twin analyses, though with limited power, suggested that night work may be associated with breast cancer risk independent of early environmental and genetic factors. These results confirm a previously described association between night shift work and breast cancer risk. Genetic influences only partially explain these associations.
Modifiable factors can influence the risk for Alzheimer's disease (AD) and serve as targets for intervention; however, the biological mechanisms linking these factors to AD are unknown. This study aims to identify plasma metabolites associated with modifiable factors for AD, including MIND diet, physical activity, smoking, and caffeine intake, and test their association with AD endophenotypes to identify their potential roles in pathophysiological mechanisms. The association between each of the 757 plasma metabolites and four modifiable factors was tested in the wisconsin registry for Alzheimer's prevention cohort of initially cognitively unimpaired, asymptomatic middle-aged adults. After Bonferroni correction, the significant plasma metabolites were tested for association with each of the AD endophenotypes, including twelve cerebrospinal fluid (CSF) biomarkers, reflecting key pathophysiologies for AD, and four cognitive composite scores. Finally, causal mediation analyses were conducted to evaluate possible mediation effects. Analyses were performed using linear mixed-effects regression. A total of 27, 3, 23, and 24 metabolites were associated with MIND diet, physical activity, smoking, and caffeine intake, respectively. Potential mediation effects include beta-cryptoxanthin in the association between MIND diet and preclinical Alzheimer cognitive composite score, hippurate between MIND diet and immediate learning, glutamate between physical activity and CSF neurofilament light, and beta-cryptoxanthin between smoking and immediate learning. Our study identified several plasma metabolites that are associated with modifiable factors. These metabolites can be employed as biomarkers for tracking these factors, and they provide a potential biological pathway of how modifiable factors influence the human body and AD risk.
Maternal vitamin D levels during pregnancy may be important for reproductive health in male offspring by regulating cell proliferation and differentiation during development. We conducted a follow-up study of 827 young men from the Fetal Programming of Semen Quality (FEPOS) cohort, nested in the Danish National Birth Cohort to investigate if maternal vitamin D levels were associated with measures of reproductive health in adult sons. These included semen characteristics, testes volume, and reproductive hormone levels and were analysed according to maternal vitamin D (25(OH)D3) levels during pregnancy. In addition, an instrumental variable analysis using seasonality in sun exposure as an instrument for maternal vitamin D levels was conducted. We found that sons of mothers with vitamin D levels < 25 nmol/L had 11% (95% CI − 19 to − 2) lower testes volume and a 1.4 (95% CI 1.0 to 1.9) times higher risk of having low testes volume (< 15 mL), in addition to 20% (95% CI − 40 to 9) lower total sperm count and a 1.6 (95% CI 0.9 to 2.9) times higher risk of having a low total sperm count (< 39 million) compared with sons of mothers with vitamin D levels > 75 nmol/L. Continuous models, spline plots and an instrumental variable analysis supported these findings. Low maternal vitamin D levels were associated with lower testes volume and lower total sperm count with indications of dose-dependency. Maternal vitamin D level above 75 nmol/L during pregnancy may be beneficial for testes function in adult sons.
Analyses from administrative databases have suggested an increased cancer incidence among individuals who experienced a myocardial infarction, especially within the first 6 months. It remains unclear to what extent this represents an underlying biological link, or can be explained by detection of pre-symptomatic cancers and shared risk factors. Cancer incidence among 1809 consecutive patients surviving hospitalization for thrombotic ST-segment-elevation myocardial infarction (STEMI; mean age 62.6 years; 26% women; 115 incident cancers) was compared to the cancer incidence among 10,052 individuals of the general population (Rotterdam Study; mean age 63.1 years; 57% women; 677 incident cancers). Pathology-confirmed cancer diagnoses were obtained through identical linkage of both cohorts with the Netherlands Cancer Registry. Cox models were used to obtain hazards ratios (HRs) adjusted for factors associated with both atherosclerosis and cancer. Over 5-year follow-up, there was no significant difference in the incidence of cancer between STEMI patients and the general population (HR 0.96, 95% CI 0.78–1.19). In the first 3 months after STEMI, cancer incidence was markedly higher among STEMI patients compared to the general population (HR 2.45, 95% CI 1.13–5.30), which gradually dissolved during follow-up ( P -for-trend 0.004). Among STEMI patients, higher C-reactive protein, higher platelet counts, and lower hemoglobin were associated with cancer incidence during the first year after STEMI (HRs 2.93 for C-reactive protein > 10 mg/dL, 2.10 for platelet count > 300*10 ⁹ , and 3.92 for hemoglobin < 7.5 mmol/L). Although rare, thrombotic STEMI might be a paraneoplastic manifestation of yet to be diagnosed cancer, and is hallmarked by a pro-inflammatory status and anemia.
Trial registration Registered into the Netherlands National Trial Register and WHO International Clinical Trials Registry Platform under shared catalogue number NTR6831.
Trials show that low-dose computed tomography (CT) lung cancer screening in long-term (ex-)smokers reduces lung cancer mortality. However, many individuals were exposed to unnecessary diagnostic procedures. This project aims to improve the efficiency of lung cancer screening by identifying high-risk participants, and improving risk discrimination for nodules. This study is an extension of the Dutch-Belgian Randomized Lung Cancer Screening Trial, with a focus on personalized outcome prediction (NELSON-POP). New data will be added on genetics, air pollution, malignancy risk for lung nodules, and CT biomarkers beyond lung nodules (emphysema, coronary calcification, bone density, vertebral height and body composition). The roles of polygenic risk scores and air pollution in screen-detected lung cancer diagnosis and survival will be established. The association between the AI-based nodule malignancy score and lung cancer will be evaluated at baseline and incident screening rounds. The association of chest CT imaging biomarkers with outcomes will be established. Based on these results, multisource prediction models for pre-screening and post-baseline-screening participant selection and nodule management will be developed. The new models will be externally validated. We hypothesize that we can identify 15–20% participants with low-risk of lung cancer or short life expectancy and thus prevent ~140,000 Dutch individuals from being screened unnecessarily. We hypothesize that our models will improve the specificity of nodule management by 10% without loss of sensitivity as compared to assessment of nodule size/growth alone, and reduce unnecessary work-up by 40–50%.
Regression discontinuity design (RDD) is a quasi-experimental method intended for causal inference in observational settings. While RDD is gaining popularity in clinical studies, there are limited real-world studies examining the performance on estimating known trial casual effects. The goal of this paper is to estimate the effect of statins on myocardial infarction (MI) using RDD and compare with propensity score matching and Cox regression. For the RDD, we leveraged a 2008 UK guideline that recommends statins if a patient's 10-year cardiovascular disease (CVD) risk score > 20%. We used UK electronic health record data from the Health Improvement Network on 49,242 patients aged 65 + in 2008-2011 (baseline) without a history of CVD and no statin use in the two years prior to the CVD risk score assessment. Both the regression discontinuity (n = 19,432) and the propensity score matched populations (n = 24,814) demonstrated good balance of confounders. Using RDD, the adjusted point estimate for statins on MI was in the protective direction and similar to the statin effect observed in clinical trials, although the confidence interval included the null (HR = 0.8, 95% CI 0.4, 1.4). Conversely, the adjusted estimates using propensity score matching and Cox regression remained in the harmful direction: HR = 2.42 (95% CI 1.96, 2.99) and 2.51 (2.12, 2.97). RDD appeared superior to other methods in replicating the known protective effect of statins with MI, although precision was poor. Our findings suggest that, when used appropriately, RDD can expand the scope of clinical investigations aimed at causal inference by leveraging treatment rules from everyday clinical practice.
Preeclampsia and cardiovascular disease (CVD) might share heritable underlying mechanisms. We investigated whether preeclampsia in daughters is associated with CVD in parents. In a register-based cohort study, we used Cox regression to compare rates of CVD (ischemic heart disease, ischemic stroke, myocardial infarction) in parents with ≥ 1 daughters who had preeclampsia and parents whose daughters did not have preeclampsia in Denmark, 1978–2018. Our cohort included 1,299,310 parents, of whom 87,251 had ≥ 1 daughters with preeclampsia and 272,936 developed CVD during 20,252,351 years of follow-up (incidence rate 135/10,000 person-years). Parents with one daughter who had preeclampsia were 1.19 times as likely as parents of daughters without preeclampsia to develop CVD at age < 55 years (hazard ratio [HR] 1.19, 95% confidence interval [CI] 1.13–1.25). Having ≥ 2 daughters who had preeclampsia yielded an HR of 1.88 (95% CI 1.39–2.53). The corresponding HRs for CVD at ≥ 55 years of age were 1.13 (95% CI 1.12–1.15) and 1.27 (95% CI 1.16–1.38). Patterns of association were similar for all CVD subtypes. Effect magnitudes did not differ for mothers and fathers (p = 0.52). Analyses by timing of preeclampsia onset in daughters suggested a tendency toward stronger associations with earlier preeclampsia onset, particularly in parents < 55 years. Preeclampsia in daughters was associated with increased risks of CVD in parents. Increasing strength of association with increasing number of affected daughters, equally strong associations for mothers and fathers, and stronger associations for CVD occurring before age 55 years suggest that preeclampsia and CVD share common heritable mechanisms.
Polygenic scores (PGS) are now commonly available in longitudinal cohort studies, leading to their integration into epidemiological research. In this work, our aim is to explore how polygenic scores can be used as exposures in causal inference-based methods, specifically mediation analyses. We propose to estimate the extent to which the association of a polygenic score indexing genetic liability to an outcome could be mitigated by a potential intervention on a mediator. To do this this, we use the interventional disparity measure approach, which allows us to compare the adjusted total effect of an exposure on an outcome, with the association that would remain had we intervened on a potentially modifiable mediator. As an example, we analyse data from two UK cohorts, the Millennium Cohort Study (MCS, N = 2575) and the Avon Longitudinal Study of Parents and Children (ALSPAC, N = 3347). In both, the exposure is genetic liability for obesity (indicated by a PGS for BMI), the outcome is late childhood/early adolescent BMI, and the mediator and potential intervention target is physical activity, measured between exposure and outcome. Our results suggest that a potential intervention on child physical activity can mitigate some of the genetic liability for childhood obesity. We propose that including PGSs in a health disparity measure approach, and causal inference-based methods more broadly, is a valuable addition to the study of gene-environment interplay in complex health outcomes.
Several studies evaluated the association between aspirin use and risk of breast cancer (BC), with inconsistent results. We identified women aged ≥ 50 years residing in Norway between 2004 and 2018, and linked data from nationwide registries; including the Cancer Registry of Norway, the Norwegian Prescription Database, and national health surveys. We used Cox regression models to estimate the association between low-dose aspirin use and BC risk, overall and by BC characteristics, women’s age and body mass index (BMI), adjusting for sociodemographic factors and use of other medications. We included 1,083,629 women. During a median follow-up of 11.6 years, 257,442 (24%) women used aspirin, and 29,533 (3%) BCs occurred. For current use of aspirin, compared to never use, we found an indication of a reduced risk of oestrogen receptor-positive (ER +) BC (hazard ratio [HR] = 0.96, 95% confidence interval [CI]: 0.92–1.00), but not ER-negative BC (HR = 1.01, 95%CI: 0.90–1.13). The association with ER + BC was only found in women aged ≥ 65 years (HR = 0.95, 95%CI: 0.90–0.99), and became stronger as the duration of use increased (use of ≥ 4 years HR = 0.91, 95%CI: 0.85–0.98). BMI was available for 450,080 (42%) women. Current use of aspirin was associated with a reduced risk of ER + BC in women with BMI ≥ 25 (HR = 0.91, 95%CI: 0.83–0.99; HR = 0.86, 95%CI: 0.75–0.97 for use of ≥ 4 years), but not in women with BMI < 25.Use of low-dose aspirin was associated with reduced risk of ER + BC, in particular in women aged ≥ 65 years and overweight women.
To assess 20-year retrospective trajectories of cardio-metabolic factors preceding dementia diagnosis among people with type 2 diabetes (T2D). We identified 227,145 people with T2D aged > 42 years between 1999 and 2018. Annual mean levels of eight routinely measured cardio-metabolic factors were extracted from the Clinical Practice Research Datalink. Multivariable multilevel piecewise and non-piecewise growth curve models assessed retrospective trajectories of cardio-metabolic factors by dementia status from up to 19 years preceding dementia diagnosis (dementia) or last contact with healthcare (no dementia). 23,546 patients developed dementia; mean (SD) follow-up was 10.0 (5.8) years. In the dementia group, mean systolic blood pressure increased 16–19 years before dementia diagnosis compared with patients without dementia, but declined more steeply from 16 years before diagnosis, while diastolic blood pressure generally declined at similar rates. Mean body mass index followed a steeper non-linear decline from 11 years before diagnosis in the dementia group. Mean blood lipid levels (total cholesterol, LDL, HDL) and glycaemic measures (fasting plasma glucose and HbA1c) were generally higher in the dementia group compared with those without dementia and followed similar patterns of change. However, absolute group differences were small. Differences in levels of cardio-metabolic factors were observed up to two decades prior to dementia diagnosis. Our findings suggest that a long follow-up is crucial to minimise reverse causation arising from changes in cardio-metabolic factors during preclinical dementia. Future investigations which address associations between cardiometabolic factors and dementia should account for potential non-linear relationships and consider the timeframe when measurements are taken.
Neurofilament light chain (NfL), a neuron-specific protein, has been related to several neurodegenerative diseases. In addition, elevated levels of NfL have also been observed in patients admitted to the hospital for stroke, suggesting that NfL as a biomarker may extend well beyond neurodegenerative diseases. Therefore, using data from the Chicago Health and Aging Project (CHAP), a population-based cohort study, we prospectively investigated the association of serum NfL levels with incident stroke and brain infarcts. During a follow-up of 3603 person-years, 133 (16.3%) individuals developed incident stroke, including ischemic and hemorrhagic. The HR (95%CI) of incident stroke was 1.28 (95%CI 1.10–1.50) per 1 standard deviation (SD) increase of log10 NfL serum levels. Compared to participants in the first tertile of NfL (i.e., lower levels), the risk of stroke was 1.68 times higher (95%CI 1.07–2.65) in those in the second tertile and 2.35 times higher (95%CI 1.45–3.81) in those in the third tertile of NfL. NfL levels were also positively associated with brain infarcts; 1-SD in log10 NfL levels was associated with 1.32 (95%CI 1.06–1.66) higher odds of one or more brain infarcts. These results suggest that NfL may serve as a biomarker of stroke in older adults.
The epidemiological and societal burden of dementia is expected to increase in the coming decades due to the world population aging. In this context, the evaluation of the potential impact of intervention scenarios aiming at reducing the prevalence of dementia risk factors is an active area of research. However, such studies must account for the associated changes in mortality and the dependence between the risk factors. Using micro-simulations, this study aims to estimate the changes in dementia burden in France in 2040 according to intervention scenarios targeting the prevention or treatment of hypertension, diabetes and physical inactivity. Accounting for their communality and their effects on mortality, the results show that the disappearance of hypertension, diabetes and physical inactivity in France in 2020 could decrease dementia prevalence by 33% among men and 26% among women in 2040 and increase the life expectancy without dementia at age 65 by 3.4 years (men) and 2.6 years (women). Among the three factors, the prevention of hypertension would be the most efficient. These projections rely on current estimates of the risk of dementia and death associated with risk factors. Thanks to the R package developed they could be refined for different countries or different interventions and updated with new estimates.
Current evidence on COVID-19 prognostic models is inconsistent and clinical applicability remains controversial. We performed a systematic review to summarize and critically appraise the available studies that have developed, assessed and/or validated prognostic models of COVID-19 predicting health outcomes. We searched six bibliographic databases to identify published articles that investigated univariable and multivariable prognostic models predicting adverse outcomes in adult COVID-19 patients, including intensive care unit (ICU) admission, intubation, high-flow nasal therapy (HFNT), extracorporeal membrane oxygenation (ECMO) and mortality. We identified and assessed 314 eligible articles from more than 40 countries, with 152 of these studies presenting mortality, 66 progression to severe or critical illness, 35 mortality and ICU admission combined, 17 ICU admission only, while the remaining 44 studies reported prediction models for mechanical ventilation (MV) or a combination of multiple outcomes. The sample size of included studies varied from 11 to 7,704,171 participants, with a mean age ranging from 18 to 93 years. There were 353 prognostic models investigated, with area under the curve (AUC) ranging from 0.44 to 0.99. A great proportion of studies (61.5%, 193 out of 314) performed internal or external validation or replication. In 312 (99.4%) studies, prognostic models were reported to be at high risk of bias due to uncertainties and challenges surrounding methodological rigor, sampling, handling of missing data, failure to deal with overfitting and heterogeneous definitions of COVID-19 and severity outcomes. While several clinical prognostic models for COVID-19 have been described in the literature, they are limited in generalizability and/or applicability due to deficiencies in addressing fundamental statistical and methodological concerns. Future large, multi-centric and well-designed prognostic prospective studies are needed to clarify remaining uncertainties.
Electronic health care databases are increasingly being used to investigate the epidemiology of congenital anomalies (CAs) although there are concerns about their accuracy. The EUROlinkCAT project linked data from eleven EUROCAT registries to electronic hospital databases. The coding of CAs in electronic hospital databases was compared to the (gold standard) codes in the EUROCAT registries. For birth years 2010–2014 all linked live birth CA cases and all children identified in the hospital databases with a CA code were analysed. Registries calculated sensitivity and Positive Predictive Value (PPV) for 17 selected CAs. Pooled estimates for sensitivity and PPV were then calculated for each anomaly using random effects meta-analyses. Most registries linked more than 85% of their cases to hospital data. Gastroschisis, cleft lip with or without cleft palate and Down syndrome were recorded in hospital databases with high accuracy (sensitivity and PPV ≥ 85%). Hypoplastic left heart syndrome, spina bifida, Hirschsprung’s disease, omphalocele and cleft palate showed high sensitivity (≥ 85%), but low or heterogeneous PPV, indicating that hospital data was complete but may contain false positives. The remaining anomaly subgroups in our study, showed low or heterogeneous sensitivity and PPV, indicating that the information in the hospital database was incomplete and of variable validity. Electronic health care databases cannot replace CA registries, although they can be used as an additional ascertainment source for CA registries. CA registries are still the most appropriate data source to study the epidemiology of CAs.
Contact tracing is a non-pharmaceutical intervention (NPI) widely used in the control of the COVID-19 pandemic. Its effectiveness may depend on a number of factors including the proportion of contacts traced, delays in tracing, the mode of contact tracing (e.g. forward, backward or bidirectional contact training), the types of contacts who are traced (e.g. contacts of index cases or contacts of contacts of index cases), or the setting where contacts are traced (e.g. the household or the workplace). We performed a systematic review of the evidence regarding the comparative effectiveness of contact tracing interventions. 78 studies were included in the review, 12 observational (ten ecological studies, one retrospective cohort study and one pre-post study with two patient cohorts) and 66 mathematical modelling studies. Based on the results from six of the 12 observational studies, contact tracing can be effective at controlling COVID-19. Two high quality ecological studies showed the incremental effectiveness of adding digital contact tracing to manual contact tracing. One ecological study of intermediate quality showed that increases in contact tracing were associated with a drop in COVID-19 mortality, and a pre-post study of acceptable quality showed that prompt contact tracing of contacts of COVID-19 case clusters / symptomatic individuals led to a reduction in the reproduction number R. Within the seven observational studies exploring the effectiveness of contact tracing in the context of the implementation of other non-pharmaceutical interventions, contact tracing was found to have an effect on COVID-19 epidemic control in two studies and not in the remaining five studies. However, a limitation in many of these studies is the lack of description of the extent of implementation of contact tracing interventions. Based on the results from the mathematical modelling studies, we identified the following highly effective policies: (1) manual contact tracing with high tracing coverage and either medium-term immunity, highly efficacious isolation/quarantine and/ or physical distancing (2) hybrid manual and digital contact tracing with high app adoption with highly effective isolation/ quarantine and social distancing, (3) secondary contact tracing, (4) eliminating contact tracing delays, (5) bidirectional contact tracing, (6) contact tracing with high coverage in reopening educational institutions. We also highlighted the role of social distancing to enhance the effectiveness of some of these interventions in the context of 2020 lockdown reopening. While limited, the evidence from observational studies shows a role for manual and digital contact tracing in controlling the COVID-19 epidemic. More empirical studies accounting for the extent of contact tracing implementation are required.
The carcinogenicity of opium consumption was recently evaluated by a Working Group convened by the International Agency for Research on Cancer (IARC). We supplement the recent IARC evaluation by conducting an extended systematic review as well as a quantitative meta-analytic assessment of the role of opium consumption and risk for selected cancers, evaluating in detail various aspects of study quality on meta-analytic findings. We searched the published literature to identify all relevant studies on opium consumption and risk of selected cancers in humans through 31 October, 2022. Meta-relative risks (mRRs) and associated 95% confidence intervals (CIs) were estimated using random-effects models for studies of cancer of the urinary bladder, larynx, lung, oesophagus, pancreas, and stomach. Heterogeneity among studies was assessed using the I2 statistic. We assessed study quality and conducted sensitivity analyses to evaluate the impact of potential reverse causation, protopathic bias, selection bias, information bias, and confounding.
In total, 2 prospective cohort studies and 33 case–control studies were included. The overall pooled mRR estimated for ‘ever or regular’ versus ‘never’ use of opium ranged from 1.50 (95% CI 1.13–1.99, I2 = 0%, 6 studies) for oesophageal cancer to 7.97 (95% CI 4.79–13.3, I2 = 62%, 7 studies) for laryngeal cancer. Analyses of cumulative opium exposure suggested greater risk of cancer associated with higher opium consumption. Findings were robust in sensitivity analyses excluding studies prone to potential methodological sources of biases and confounding. Findings support an adverse association between opium consumption and cancers of the urinary bladder, larynx, lung, oesophagus, pancreas and stomach.
Neither vaccination nor natural infection result in long-lasting protection against SARS-COV-2 infection and transmission, but both reduce the risk of severe COVID-19. To generate insights into optimal vaccination strategies for prevention of severe COVID-19 in the population, we extended a Susceptible-Exposed-Infectious-Removed (SEIR) mathematical model to compare the impact of vaccines that are highly protective against severe COVID-19 but not against infection and transmission, with those that block SARS-CoV-2 infection. Our analysis shows that vaccination strategies focusing on the prevention of severe COVID-19 are more effective than those focusing on creating of herd immunity. Key uncertainties that would affect the choice of vaccination strategies are: (1) the duration of protection against severe disease, (2) the protection against severe disease from variants that escape vaccine-induced immunity, (3) the incidence of long-COVID and level of protection provided by the vaccine, and (4) the rate of serious adverse events following vaccination, stratified by demographic variables.
While higher circulating 25-hydroxyvitamin D concentrations have been reported to be associated with decreased risk of all-cause mortality, evidence on dietary vitamin D intake is limited and inconsistent. We investigated whether vitamin D intake is associated with all-cause and cause-specific mortality among Japanese adults. Participants were 42,992 men and 50,693 women who responded to the second survey of the Japan Public Health Center-based Prospective Study (1995–1998) and who were followed up for mortality through 2018. Dietary intake was ascertained using a validated food frequency questionnaire. Hazard ratios of deaths from the second survey to December 2018 were estimated using Cox proportional hazard regression analysis. During follow-up, we identified 22,630 deaths. Overall, the third and fourth quintiles, but not the highest quintile, of vitamin D intake were each associated with a significantly lower risk of all-cause mortality. In subgroups characterized by low sunlight exposure, risk of all-cause mortality decreased linearly with increasing vitamin D intake. The multivariable-adjusted hazard ratios (95% confidence intervals) of all-cause mortality for the highest versus lowest quintile of vitamin D intake were 0.87 (0.79–0.95) in women and 0.88 (0.79–0.97) in residents of higher latitude areas. Lower risk was also observed for all-cause mortality in participants with hypertension and for heart disease mortality in those with higher calcium intake. Higher vitamin D intake was associated with decreased risk of ischemic stroke and pneumonia mortality. Higher dietary vitamin D was associated with a lower risk of mortality among individuals with low sunlight exposure or hypertension. Individuals with potentially low vitamin D may benefit from increasing dietary vitamin D intake for the prevention of premature death.
To investigate the association between circulating lipoprotein(a) (Lp(a)) and risk of all-cause and cause-specific mortality in the general population and in patients with chronic diseases, and to elucidate the dose-response relations.
Methods and results
We searched literature to find prospective studies reporting adjusted risk estimates on the association of Lp(a) and mortality outcomes. Forty-three publications, reporting on 75 studies (957,253 participants), were included. The hazard ratios (HRs) and 95% confidence intervals (95%CI ) for the top versus bottom tertile of Lp(a) levels and risk of all-cause mortality were 1.09 (95%CI: 1.01–1.18, I ² : 75.34%, n = 19) in the general population and 1.18 (95%CI: 1.04–1.34, I ² : 52.5%, n = 12) in patients with cardiovascular diseases (CVD). The HRs for CVD mortality were 1.33 (95%CI: 1.11–1.58, I ² : 82.8%, n = 31) in the general population, 1.25 (95%CI: 1.10–1.43, I ² : 54.3%, n = 17) in patients with CVD and 2.53 (95%CI: 1.13–5.64, I ² : 66%, n = 4) in patients with diabetes mellitus. Linear dose-response analyses revealed that each 50 mg/dL increase in Lp(a) levels was associated with 31% and 15% greater risk of CVD death in the general population and in patients with CVD. No non-linear dose-response association was observed between Lp(a) levels and risk of all-cause or CVD mortality in the general population or in patients with CVD (P nonlinearity > 0.05).
This study provides further evidence that higher Lp(a) levels are associated with higher risk of all-cause mortality and CVD-death in the general population and in patients with CVD. These findings support the ESC/EAS Guidelines that recommend Lp(a) should be measured at least once in each adult person’s lifetime, since our study suggests those with higher Lp(a) might also have higher risk of mortality.
To test the main hypothesis that anticoagulation reduces risk of hospitalization, intensive care unit (ICU) admission and death in COVID-19. Nested case–control study among patients with atrial fibrillation (AF) in Stockholm. COVID-19 cases were matched to five disease-free controls with same sex, born within ± 1 years. Source population was individuals in Stockholm with AF 1997–2020. Swedish regional and national registers are used. National registers cover hospitals and outpatient clinics, local registers cover primary care. Records were linked through the personal identity number assigned to each Swedish resident. Cases were individuals with COVID-19 (diagnosis, ICU admission, or death). The AF source population consisted of 179,381 individuals from which 7548 cases were identified together with 37,145 controls. The number of cases (controls) identified from hospitalization, ICU admission or death were 5916 (29,035), 160 (750) and 1472 (7,360). The proportion of women was 40% for hospitalization and death, but 20% and 30% for admission to ICU in wave one and two, respectively. Primary outcome was mortality, secondary outcome was hospitalization, tertiary outcome was ICU admission, all with COVID-19. Odds ratios (95% confidence interval) for antithrombotics were 0.79 (0.66–0.95) for the first wave and 0.80 (0.64–1.01) for the second wave. Use of anticoagulation among patients with arrythmias infected with COVID-19 is associated with lower risk of hospitalization and death. If further COVID-variants emerge, or other infections with prothrombotic properties, this emphasize need for physicians to ensure compliance among vulnerable patients.
AimsDiabetes mellitus is a chronic disease that limits the quality and duration of life. We aimed to estimate the impact of demographic change on the burden of prediabetes and diabetes between 2010 and 2021, and the projections to 2030 and 2045 in Turkiye.Materials and methodsPrediabetes and diabetes estimates were calculated by direct standardization method using age- and sex-specific prevalence data from the previous ‘Turkish Epidemiology Survey of Diabetes, Hypertension, Obesity and Endocrine Disease’ (TURDEP-II) as reference. The 2010–2021 population demographics were obtained from TurkStat. Comparative age-adjusted diabetes prevalence was estimated using the standard population models of world and Europe.ResultsEstimates depicted that the population (20–84 years) of any degree of glucose intolerance in Turkiye increased by over 5.7 million (diabetes: 2.4 million and prediabetes: 3.3 million) from 2010 to 2021. While the increase in prediabetes and diabetes prevalence was 24.3% and 35.2% in overall population, corresponding increase were 46.5% and 51.3% in the elderly. Estimated prevalence of prediabetes and diabetes in 2021 was significantly higher in women than in men (prediabetes: 32.6% vs. 25.2%; diabetes: 17.1% vs. 14.2%). The comparative age-adjusted diabetes prevalence to the European population model was higher than that of the world population model (19.4% vs. 15.0%). According to the projections the prevalence of diabetes will reach 17.5% in 2030 and 19.2% in 2045.
Assuming age- and sex-specific diabetes prevalence of TURDEP-II survey remained constant, this study revealed that the number of people with diabetes in the general population (particularly in the elderly) in the last 11 years in Turkiye has increased in parallel with the population growth and aging; it will continue to grow over the coming decades. This means the burden of diabetes on the social, economic and health services will remain to increase. The fact suggests that there is an urgent need for re-organization of care as well as to develop and implement a country-specific prevention program to reduce this burden.
Although high body-mass index (BMI) is associated with increased risk of developing colorectal cancer (CRC), many CRC patients lose weight before diagnosis. BMI is often reported close to diagnosis, which may have led to underestimation or even reversal of direction of the BMI-CRC association. We aimed to assess if and to what extent potential bias from prediagnostic weight loss has been considered in available epidemiological evidence. We searched PubMed and Web of Science until May 2022 for systematic reviews and meta-analyses investigating the BMI-CRC association. Information on design aspects and results was extracted, including if and how the reviews handled prediagnostic weight loss as a potential source of bias. Additionally, we analyzed how individual cohort studies included in the latest systematic review handled the issue. Overall, 18 reviews were identified. None of them thoroughly considered or discussed prediagnostic weight loss as a potential source of bias. The majority (15/21) of cohorts included in the latest review did not exclude any initial years of follow-up from their main analysis. Although the majority of studies reported having conducted sensitivity analyses in which initial years of follow-up were excluded, results were reported very heterogeneously and mostly for additional exclusions of 1–2 years only. Where explicitly reported, effect estimates mostly increased with increasing length of exclusion. The impact of overweight and obesity on CRC risk may be larger than suggested by the existing epidemiological evidence.
Multiple studies across global populations have established the primary symptoms characterising Coronavirus Disease 2019 (COVID-19) and long COVID. However, as symptoms may also occur in the absence of COVID-19, a lack of appropriate controls has often meant that specificity of symptoms to acute COVID-19 or long COVID, and the extent and length of time for which they are elevated after COVID-19, could not be examined. We analysed individual symptom prevalences and characterised patterns of COVID-19 and long COVID symptoms across nine UK longitudinal studies, totalling over 42,000 participants. Conducting latent class analyses separately in three groups (‘no COVID-19’, ‘COVID-19 in last 12 weeks’, ‘COVID-19 > 12 weeks ago’), the data did not support the presence of more than two distinct symptom patterns, representing high and low symptom burden, in each group. Comparing the high symptom burden classes between the ‘COVID-19 in last 12 weeks’ and ‘no COVID-19’ groups we identified symptoms characteristic of acute COVID-19, including loss of taste and smell, fatigue, cough, shortness of breath and muscle pains or aches. Comparing the high symptom burden classes between the ‘COVID-19 > 12 weeks ago’ and ‘no COVID-19’ groups we identified symptoms characteristic of long COVID, including fatigue, shortness of breath, muscle pain or aches, difficulty concentrating and chest tightness. The identified symptom patterns among individuals with COVID-19 > 12 weeks ago were strongly associated with self-reported length of time unable to function as normal due to COVID-19 symptoms, suggesting that the symptom pattern identified corresponds to long COVID. Building the evidence base regarding typical long COVID symptoms will improve diagnosis of this condition and the ability to elicit underlying biological mechanisms, leading to better patient access to treatment and services.
Research suggests a protective effect of religious service attendance on various health outcomes. However, most research has been done in religious societies, raising the question of whether these associations are also prominent in secular cultures. Here we examine mortality and hospitalisations by religious service attendance among men and women in a secular society. We performed a cohort study including 2987 Danes aged 40+ interviewed in SHARE from 2004 to 2007 and followed up in the Danish registries until 2018. We used Cox regressions and negative binomial regressions to examine associations, including interactions with sex and adjusting for age, wave, socioeconomic factors, lifestyle factors, body mass index, and history of diseases. Overall, 5.0% of men and 6.6% of women reported that they had taken part in a religious organisation within the last month. Among 848 deaths, we found lower mortality for people who attended religious services (hazard ratio (HR) 0.70; 95% CI 0.50–0.99). There was evidence for an association among women (HR 0.56; 95% CI 0.35–0.89), but not among men (HR 0.95; 95% CI 0.59–1.53). In contrast, regarding hospital admissions (n = 12,010), we found lower hospitalisation rates among men who attended religious services (incidence rate ratio (IRR) 0.67; 95% CI 0.45–0.98), whereas no association was found among women (IRR 0.95; 95% CI 0.70–1.29). Sensitivity analyses with E-values were moderately robust. Our results contribute to the limited literature on possible health benefits of religious service attendance in secular societies, demonstrating lower mortality among women and fewer hospitalisations among men.
Air pollution and multimorbidity are two of the most important challenges for Public Health worldwide. Although there is a large body of evidence linking air pollution with the development of different single chronic conditions, the evidence about the relationship between air pollution and multimorbidity (the co-occurrence of multiple long-term conditions) is sparse. To obtain evidence about this relationship could be challenging and different aspects should be considered, such as its multifaceted and complex nature, the specific pollutants and their potential influence on health, their levels of exposure over time, or the data that could be used for its study. This evidence could be instrumental to inform the development of new recommendations and measures to reduce harmful levels of air pollutants, as means to prevent the development of multimorbidity and reduce its burden.
Most work on extending (generalizing or transporting) inferences from a randomized trial to a target population has focused on estimating average treatment effects (i.e., averaged over the target population’s covariate distribution). Yet, in the presence of strong effect modification by baseline covariates, the average treatment effect in the target population may be less relevant for guiding treatment decisions. Instead, the conditional average treatment effect (CATE) as a function of key effect modifiers may be a more useful estimand. Recent work on estimating target population CATEs using baseline covariate, treatment, and outcome data from the trial and covariate data from the target population only allows for the examination of heterogeneity over distinct subgroups. We describe flexible pseudo-outcome regression modeling methods for estimating target population CATEs conditional on discrete or continuous baseline covariates when the trial is embedded in a sample from the target population (i.e., in nested trial designs). We construct pointwise confidence intervals for the CATE at a specific value of the effect modifiers and uniform confidence bands for the CATE function. Last, we illustrate the methods using data from the Coronary Artery Surgery Study (CASS) to estimate CATEs given history of myocardial infarction and baseline ejection fraction value in the target population of all trial-eligible patients with stable ischemic heart disease.
The role of regular physical activity in preventing vascular and non-vascular disease is well established. Chronic kidney disease (CKD) is a major cause of global morbidity and mortality and largely preventable, but it is uncertain if regular physical activity can reduce the risk of CKD. Using a systematic review and meta-analysis of published observational cohort studies in the general population, we sought to assess the association between physical activity and CKD risk. Relevant studies with at least one-year of follow-up were sought from inception until 02 May 2022 in MEDLINE, Embase, Web of Science, and manual search of relevant articles. Relative risks (RRs) with 95% confidence intervals (CIs) for the maximum versus the minimal amount of physical activity groups were pooled using random effects meta-analysis. The quality of the evidence was evaluated using the GRADE tool. A total of 12 observational cohort studies comprising 1,281,727 participants and 66,217 CKD events were eligible for the analysis. The pooled multivariable-adjusted RR (95% CI) of CKD comparing the most versus the least physically active groups was 0.91 (0.85–0.97). The association was consistent across several study level subgroups. Exclusion of any single study at a time from the meta-analysis did not change the direction or significance of the association. There was no evidence of small study effects among contributing studies. The GRADE quality of the evidence was low. In the general population, individuals who are most physically active have a lowered risk of CKD compared to those who are not or least physically active. CRD42022327640.
Elevated blood pressure and hypertension have been associated with increased risk of atrial fibrillation in a number of epidemiological studies, however, the strength of the association has differed between studies. We conducted a systematic review and meta-analysis of the association between blood pressure and hypertension and atrial fibrillation. PubMed and Embase databases were searched for studies of hypertension and blood pressure and atrial fibrillation up to June 6th 2022. Cohort studies reporting adjusted relative risk (RR) estimates and 95% confidence intervals (CIs) of atrial fibrillation associated with hypertension or blood pressure were included. A random effects model was used to estimate summary RRs. Sixty eight cohort studies were included in the meta-analysis. The summary RR was 1.50 (95% CI: 1.42–1.58, I2 = 98.1%, n = 56 studies) for people with hypertension compared to those without hypertension (1,080,611 cases, 30,539,230 participants), 1.18 (95% CI: 1.16–1.21, I2 = 65.9%, n = 37 studies) per 20 mmHg increase in systolic blood pressure (346,471 cases, 14,569,396 participants), and 1.07 (95% CI: 1.03–1.11, I2 = 91.5%, n = 22 studies) per 10 mmHg increase in diastolic blood pressure (332,867 cases, 14,354,980 participants). There was evidence of a nonlinear association between diastolic blood pressure and atrial fibrillation with a steeper increase in risk at lower levels of diastolic blood pressure, but for systolic blood pressure the association appeared to be linear. For both systolic and diastolic blood pressure, the risk increased even within the normal range of blood pressure and persons at the high end of systolic and diastolic blood pressure around 180/110 mmHg had a 1.8–2.3 fold higher risk of atrial fibrillation compared to those with a blood pressure of 90/60 mmHg. These results suggest that elevated blood pressure and hypertension increases the risk of atrial fibrillation and there is some increase in risk even within the normal range of systolic and diastolic blood pressure.
Out-of-home care has been linked to excess mortality across the lifespan. We examined whether this association is modified by the age at first out-of-home care placement and the number of placements. In this population-based cohort study, we used register data covering all children born in Denmark between 1 and 1980 and 31 December 1999, totalling 1,111,193 individuals followed until 31 December 2018. We divided participants according to sex, out-of-home care status, age at first placement, and the number of placements. We estimated adjusted hazard ratios and hazard differences per 10,000 person-years for all-cause mortality and mortality due to suicide, accidents, and cancer between ages 18 and 39. 53,015 (4.8%) of the participants were placed in out-of-home care before age 18. The adjusted hazard ratio for all-cause mortality was 3.4 (95% CI 3.1–3.7) for males and 4.7 (4.0–5.4) for females, corresponding to 20.6 (19.0–22.2) and 10.3 (9.1–11.5) additional deaths per 10,000 individuals annually among males and females, respectively. Associations did not vary substantially according to age at first placement or the number of placements. Both males and females with a history of out-of-home care were more likely to die from suicide, accidents, and cancer compared with their peers. We show a markedly higher all-cause and cause-specific mortality among children who have been placed in out-of-home care, but contrary to our hypothesis, age at first placement and the number of placements did not modify this relation. These results warrant further investigation into potential target points for interventions that may prevent premature mortality in this group of disadvantaged individuals.
Mortality was studied in a cohort of 4831 men from Estonia who participated in the environmental cleanup of the radioactively contaminated areas around Chernobyl in 1986–1991. Their mortality in 1986–2020 was compared with the mortality in the Estonian male population. A total of 1503 deaths were registered among the 4812 traced men. The all-cause standardized mortality ratio (SMR) was 1.04 (95% CI 0.99–1.09). All-cancer mortality was elevated (SMR 1.16, 95% CI 1.03–1.28). Radiation-related cancers were in excess (SMR 1.20, 95% CI 1.03–1.36); however, the excesses could be attributed to tobacco and alcohol consumption. For smoking-related cancers, the SMR was 1.20 (95% CI 1.06–1.35) and for alcohol-related cancers the SMR was 1.56 (95% CI 1.26–1.86). Adjusted relative risks (ARR) of all-cause mortality were increased among workers who stayed in the Chernobyl area ≥ 92 days (ARR 1.20, 95% CI 1.08–1.34), were of non-Estonian ethnicity (ARR 1.33, 95% CI 1.19–1.47) or had lower (basic or less) education (ARR 1.63, 95% CI 1.45–1.83). Suicide mortality was increased (SMR 1.31, 95% CI 1.05–1.56), most notably among men with lower education (ARR 2.24, 95% CI 1.42–3.53). Our findings provide additional evidence that unhealthy behaviors such as alcohol and smoking play an important role in shaping cancer mortality patterns among Estonian Chernobyl cleanup workers. The excess number of suicides suggests long-term psychiatric and substance use problems tied to Chernobyl-related stressors, i.e., the psychosocial impact was greater than any direct carcinogenic effect of low-dose radiation.
Research-ready data (data curated to a defined standard) increase scientific opportunity and rigour by integrating the data environment. The development of research platforms has highlighted the value of research-ready data, particularly for multi-cohort analyses. Following stakeholder consultation, a standard data model (C-Surv) optimised for data discovery, was developed using data from 5 population and clinical cohort studies. The model uses a four-tier nested structure based on 18 data themes selected according to user behaviour or technology. Standard variable naming conventions are applied to uniquely identify variables within the context of longitudinal studies. The data model was used to develop a harmonised dataset for 11 cohorts. This dataset populated the Cohort Explorer data discovery tool for assessing the feasibility of an analysis prior to making a data access request. Data preparation times were compared between cohort specific data models and C-Surv.
It was concluded that adopting a common data model as a data standard for the discovery and analysis of research cohort data offers multiple benefits.
To investigate the associations of milk intake (non-fermented and fermented milk), lactase persistence (LCT-13910 C/T) genotype (a proxy for long-term non-fermented milk intake), and gene-milk interaction with risks of cardiovascular disease (CVD) and CVD mortality. Also, to identify the CVD-related plasma proteins and lipoprotein subfractions associated with milk intake and LCT-13910 C/T genotype. The prospective cohort study included 20,499 participants who were followed up for a mean of 21 years. Dietary intake was assessed using a modified diet history method. Cox proportional hazards regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). After adjusting for sociodemographic and lifestyle factors, higher non-fermented milk intake was significantly associated with higher risks of coronary heart disease (CHD) and CVD mortality, whereas higher fermented milk intake was significantly associated with lower risks of CVD and CVD mortality. The genotype associated with higher milk (mainly non-fermented) intake was positively associated with CHD (CT/TT vs. CC HR = 1.27; 95% CI: 1.03, 1.55) and CVD (HR = 1.22; 95% CI: 1.05, 1.42). The association between rs4988235 genotype and CVD mortality was stronger in participants with higher milk intake than among participants with lower intake (P for interaction < 0.05). Furthermore, leptin, HDL, and large HDL were associated with non-fermented milk intake, while no plasma proteins or lipoprotein subfractions associated with fermented milk intake and LCT-13910 C/T genotype were identified. In conclusion, non-fermented milk intake was associated with higher risks of CHD and CVD mortality, as well as leptin and HDL, whereas fermented milk intake was associated with lower risks of CVD and CVD mortality.
Pregnancy-related factors are important for short- and long-term health in mothers and offspring. The nationwide population-based Swedish Medical Birth Register (MBR) was established in 1973. The present study describes the content and quality of the MBR, using original MBR data, Swedish-language and international publications based on the MBR.
The MBR includes around 98% of all births in Sweden. From 1982 onwards, the MBR is based on prospectively recorded information in standardized antenatal, obstetric, and neonatal records. When the mother and infant are discharged from hospital, this information is forwarded to the MBR, which is updated annually. Maternal data include information from first antenatal visit on self-reported obstetric history, infertility, diseases, medication use, cohabitation status, smoking and snuff use, self-reported height and measured weight, allowing calculation of body mass index. Birth and neonatal data include date and time of birth, mode of delivery, singleton or multiple birth, gestational age, stillbirth, birth weight, birth length, head circumference, infant sex, Apgar scores, and maternal and infant diagnoses/procedures, including neonatal care. The overall quality of the MBR is very high, owing to the semi-automated data extraction from the standardized regional electronic health records, Sweden’s universal access to antenatal care, and the possibility to compare mothers and offspring to the Total Population Register in order to identify missing records. Through the unique personal identity numbers of mothers and live-born offspring, the MBR can be linked to other health registers. The Swedish MBR contains high-quality pregnancy-related information on more than 5 million births during five decades.
Dementia constitutes a worldwide concern. To characterize the age- and sex-specific modifiable risk factor profiles of dementia, we included 497,401 UK Biobank participants (mean age = 56.5 years) without dementia at baseline (2006–2010) and followed them until March 2021. Cox proportional hazard models were used to estimate the age- and sex-specific hazard ratios (HRs) of incident dementia associated with socioeconomic (less education and high Townsend deprivation index), lifestyle (non-moderate alcohol intake, current smoking, suboptimal diet, physical inactivity, and unhealthy sleep duration), and health condition factors (hypertension, diabetes, cardiovascular diseases, and depressive symptoms). We also calculated the population attributable fractions (PAFs) of these factors. During follow-up (mean = 11.6 years), we identified 6564 dementia cases. HRs for the risk factors were similar between the sexes, while most factors showed stronger associations among younger participants. For example, the HRs of smoking were 1.74 (95% CI: 1.23, 2.47) for individuals aged < 50 years, and 1.18 (1.05, 1.33) for those aged ≥ 65 years. Overall, 46.8% (37.4%, 55.2%) of dementia cases were attributable to the investigated risk factors. The PAFs of the investigated risk factors also decreased with age, but that for health condition risk factors decreased with lower magnitude than socioeconomic and lifestyle risk factors. The stronger associations and greater PAFs of several modifiable risk factors for dementia among younger adults than older participants underscored the importance of dementia prevention from an earlier stage across the adult life course.
Many health services, including cancer care, have been affected by the COVID-19 epidemic. This study aimed at providing a systematic review of the impact of the epidemic on cancer diagnostic tests and diagnosis worldwide. In our systematic review and meta-analysis, databases such as Pubmed, Proquest and Scopus were searched comprehensively for articles published between January 1st, 2020 and December 12th, 2021. Observational studies and articles that reported data from single clinics and population registries comparing the number of cancer diagnostic tests and/or diagnosis performed before and during the pandemic, were included. Two pairs of independent reviewers extracted data from the selected studies. The weighted average of the percentage variation was calculated and compared between pandemic and pre-pandemic periods. Stratified analysis was performed by geographic area, time interval and study setting. The review was registered on PROSPERO (ID: CRD42022314314). The review comprised 61 articles, whose results referred to the period January–October 2020. We found an overall decrease of − 37.3% for diagnostic tests and − 27.0% for cancer diagnosis during the pandemic. For both outcomes we identified a U-shaped temporal trend, with an almost complete recovery for the number of cancer diagnosis after May 2020. We also analyzed differences by geographic area and screening setting. We provided a summary estimate of the decrease in cancer diagnosis and diagnostic tests, during the first phase of the COVID-19 pandemic. The delay in cancer diagnosis could lead to an increase in the number of avoidable cancer deaths. Further research is needed to assess the impact of the pandemic measures on cancer treatment and mortality.
Laboratory and animal research support a protective role for vitamin D in breast carcinogenesis, but epidemiologic studies have been inconclusive. To examine comprehensively the relationship of circulating 25-hydroxyvitamin D [25(OH)D] to subsequent breast cancer incidence, we harmonized and pooled participant-level data from 10 U.S. and 7 European prospective cohorts. Included were 10,484 invasive breast cancer cases and 12,953 matched controls. Median age (interdecile range) was 57 (42–68) years at blood collection and 63 (49–75) years at breast cancer diagnosis. Prediagnostic circulating 25(OH)D was either newly measured using a widely accepted immunoassay and laboratory or, if previously measured by the cohort, calibrated to this assay to permit using a common metric. Study-specific relative risks (RRs) for season-standardized 25(OH)D concentrations were estimated by conditional logistic regression and combined by random-effects models. Circulating 25(OH)D increased from a median of 22.6 nmol/L in consortium-wide decile 1 to 93.2 nmol/L in decile 10. Breast cancer risk in each decile was not statistically significantly different from risk in decile 5 in models adjusted for breast cancer risk factors, and no trend was apparent (P-trend = 0.64). Compared to women with sufficient 25(OH)D based on Institute of Medicine guidelines (50– < 62.5 nmol/L), RRs were not statistically significantly different at either low concentrations (< 20 nmol/L, 3% of controls) or high concentrations (100– < 125 nmol/L, 3% of controls; ≥ 125 nmol/L, 0.7% of controls). RR per 25 nmol/L increase in 25(OH)D was 0.99 [95% confidence intervaI (CI) 0.95–1.03]. Associations remained null across subgroups, including those defined by body mass index, physical activity, latitude, and season of blood collection. Although none of the associations by tumor characteristics reached statistical significance, suggestive inverse associations were seen for distant and triple negative tumors. Circulating 25(OH)D, comparably measured in 17 international cohorts and season-standardized, was not related to subsequent incidence of invasive breast cancer over a broad range in vitamin D status.
We tested the hypothesis that six toxic risk factors from the TIGAR-O classification system are equally important for risk of chronic pancreatitis, at the level of the individual patient and in the general population. 108,438 women and men aged 20–100 years participating in the Copenhagen General Population Study from 2003 to 2015 were included. Associations of smoking, alcohol intake, waist/hip ratio, kidney function, plasma triglycerides, plasma Ca²⁺, and diseases within the causal pathway with risk of chronic pancreatitis, and corresponding population attributable risks were estimated. Information on chronic pancreatitis was from national Danish health registries. During median 9 years (range: 0–15) of follow-up, 313 individuals had a first diagnosis of chronic pancreatitis; the incidence of chronic pancreatitis per 10,000 person-years were 3.1 overall, 2.8 in women, and 3.5 in men. Of the six toxic risk factors and relative to individuals with low values, individuals in the top 5% had hazard ratios for chronic pancreatitis of 3.1(95% CI 2.1–4.5) for pack-years smoked, 2.5(1.5–4.0) for alcohol intake, and 1.6(1.1–2.6) for plasma triglycerides. Corresponding values versus those without the baseline disease were 12.6 (7.9–20.2) for acute pancreatitis, 1.9 (1.2–2.8) for gallstone disease, and 1.9 (1.3–2.7) for diabetes mellitus. The highest population attributable fractions were for women (1) ever smoking (31%), (2) gallstone disease (5%), and (3) diabetes mellitus (4%), and for men (1) ever smoking (38%), (2) acute pancreatitis (7%)/high alcohol intake (7%), and (3) high plasma triglycerides (5%). Smoking is the most important risk factor for chronic pancreatitis in the general population.
Current estimates of pandemic SARS-CoV-2 spread in Germany using infectious disease models often do not use age-specific infection parameters and are not always based on age-specific contact matrices of the population. They also do usually not include setting-or pandemic phase-based information from epidemiological studies of reported cases and do not account for age-specific underdetection of reported cases. Here, we report likely pandemic spread using an age-structured model to understand the age-and setting-specific contribution of contacts to transmission during different phases of the COVID-19 pandemic in Germany. We developed a deterministic SEIRS model using a pre-pandemic contact matrix. The model was optimized to fit age-specific SARS-CoV-2 incidences reported by the German National Public Health Institute (Robert Koch Institute), includes information on setting-specific reported cases in schools and integrates age-and pandemic period-specific parameters for underdetection of reported cases deduced from a large population-based seroprevalence studies. Taking age-specific underreporting into account, younger adults and teenagers were identified in the modeling study as relevant contributors to infections during the first three pandemic waves in Germany. For the fifth wave, the Delta to Omicron transition , only age-specific parametrization reproduces the observed relative and absolute increase in pediatric hospitalizations in Germany. Taking into account age-specific underdetection did not change considerably how much contacts in schools contributed to the total burden of infection in the population (up to 12% with open schools under hygiene measures in the third wave). Accounting for the pandemic phase and age-specific underreporting is important to correctly identify those groups of the population in which quarantine, testing, vaccination, and contact-reduction measures are likely to be most effective and efficient. Age-specific parametrization is also highly relevant to generate informative age-specific output for decision makers and resource planers.
Expected beneficial health effects is a major reason why people purchase organically produced foods, although the existing evidence is limited. We investigated if organic food consumption, overall and by specific food groups, is associated with the incidence of cancer.
We used data from the Danish Diet, Cancer and Health cohort. Organic food consumption was reported for vegetables, fruits, dairy products, eggs, meat, and bread and cereal products. Consumption was summarized into an overall organic food score, evaluated as a continuous variable and in categories specified as never, low, medium, and high consumption. We followed 41,928 participants for a median of 15 years, during which 9,675 first cancer cases were identified in the Danish Cancer Registry. We used cox proportional hazard models adjusted for sociodemographic and lifestyle variables to estimate associations between organic food consumption and cancer incidence.
No association was observed between intakes of organic foods and incidence of overall cancer. When compared to never eating organic foods, overall organic food consumption was associated with a lower incidence of stomach cancer (low: HR = 0.50, 95% CI: 0.32–0.78, medium: HR = 0.50, 95% CI: 0.32–0.80, high: HR = 0.54, 95% CI: 0.27–1.07, p-trend = 0.09), and higher incidence of non-Hodgkin lymphoma (low: HR = 1.45, 95% CI: 1.01–2.10, medium: HR = 1.35, 95% CI: 0.93–1.96, high: HR = 1.97, 95% CI: 1.28–3.04, p-trend = 0.05). Similar patterns were observed for the specific food groups.
Our study does not support an association between organic food consumption and incidence of overall cancer. The scarce existing literature shows conflicting results with risk of specific cancers.
Editor’s Note: This Essay is the last paper of Olli Miettinen. I discussed it with him until about a week before his death on November 24, 2021. The article had gone through many iterations, as was the case with all his contributions to the European Journal of Epidemiology over the years. As Miettinen writes, it can be viewed as his academic mini-bio. Albert Hofman