Robin Haring

University of Greifswald, Griefswald, Mecklenburg-Vorpommern, Germany

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Publications (79)408.11 Total impact

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    ABSTRACT: Context and objectives: The association of endogenous androgens and sex hormone-binding globulin (SHBG) with metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM) mostly 23562 refers to small and selected study samples with immunoassay-based measurements. Thus, we investigated the association of hormone levels with MetS and T2DM in women from a large population-based sample. Design, setting, and participants: A total of 2077 women from the Study of Health in Pomerania were assessed at baseline (N = 3160, 1997-2001) and 5-year follow-up (N = 1711, 2002-2006). Main Outcomes and Measures: We investigated associations of total testosterone (T) and androstenedione measured by liquid chromatography-tandem mass spectrometry, SHBG by immunoassay, and free T and free androgen index with MetS and T2DM. Results: Baseline prevalence of MetS and T2DM was 23.1% (N = 365) and 9.5% (N = 196), with an incidence of 17.7 and 7.0 per 1.000 person-years, respectively. Cross-sectional analyses yielded inverse associations of SHBG with MetS (relative risk [RR], 0.67; 95% confidence interval [CI], 0.60-0.74) and T2DM (RR, 0.61; 95% CI, 0.50-0.74) after multivariable adjustment. In longitudinal analyses, only age-adjusted models showed an inverse association of baseline SHBG with incident MetS (RR, 0.61; 95% CI, 0.51-0.73) and T2DM (RR, 0.58; 95% CI, 0.43-0.78). Multivariable-adjusted models stratified by menopausal status revealed an inverse association between SHBG and incident MetS risk in postmenopausal women (RR, 0.65; 95% CI, 0.51-0.81). Conclusions: This longitudinal population-based study revealed independent inverse associations of SHBG with MetS and T2DM, suggesting low SHBG as a potential risk marker for cardiometabolic morbidity, especially among postmenopausal women.
    No preview · Article · Oct 2015 · The Journal of Clinical Endocrinology and Metabolism
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    ABSTRACT: Objectives: The aims of this study were to ascertain whether women with high levels of serum total testosterone (TT) or low levels of sex hormone-binding globulin (SHBG) are more likely to develop cardiovascular disease (CVD), and to investigate potential associations between sex hormones and mortality (all-cause, as well as cause-specific) in the general population. Study design and main outcome measures: Data on 2129 women with a mean age of 49.0 years were obtained from the population-based Study of Health in Pomerania over a median follow-up of 10.9 years. Associations of baseline levels of TT, SHBG, and rostenedione (ASD), and free testosterone (fT), and of the free androgen index (FAI), with follow-up CVD morbidity, as well as all-cause and CVD mortality, were analyzed using multivariable regression modeling. Results: At baseline the prevalence rate of CVD was 17.8% (378 women) and the incidence of CVD over the follow-up was 50.9 per 1000 person-years. We detected an inverse association between SHBG and baseline CVD in age-adjusted models (relative risk per standard deviation increase: 0.83; 95% confidence interval: 0.74-0.93). We did not detect any significant associations between sex hormone concentrations and incident CVD in age- and multivariable-adjusted Poisson regression models. Furthermore, none of the sex hormones (TT, SHBG, ASD, fT, FAI) were associated with all-cause mortality. Conclusions: This population-based cohort study did not yield any consistent associations between sex hormones in women and incident CVD or mortality risk.
    No preview · Article · Sep 2015 · Maturitas
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    ABSTRACT: Despite observational evidence from epidemiological and clinical studies associating sex hormones with various cardiometabolic risk factors or diseases, pathophysiological explanations are sparse to date. To reveal putative functional insights, we analyzed associations between sex hormone levels and whole blood gene expression profiles. We used data of 991 individuals from the population-based Study of Health in Pomerania (SHIP-TREND) with whole blood gene expression levels determined by array-based transcriptional profiling and serum concentrations of total testosterone (TT), sex hormone-binding globulin (SHBG), free testosterone (free T), dehydroepiandrosterone sulfate (DHEAS), androstenedione (AD), estradiol (E2), and estrone (E1) measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and immunoassay. Associations between sex hormone concentrations and gene expression profiles were analyzed using sex-specific regression models adjusted for age, body mass index, and technical covariables. In men, positive correlations were detected between AD and DDIT4 mRNA levels, as well as between SHBG and the mRNA levels of RPIA, RIOK3, GYPB, BPGM, and RAB2B. No additional significant associations were observed. Besides the associations between AD and DDIT4 expression and SHBG and the transcript levels of RPIA, RIOK3, GYPB, BPGM, and RAB2B, the present study did not indicate any association between sex hormone concentrations and whole blood gene expression profiles in men and women from the general population.
    Preview · Article · May 2015 · PLoS ONE
  • T. Fischer · M. Dörr · M. Langanke · R. Haring

    No preview · Chapter · Jan 2015
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    ABSTRACT: Background Elevated glycated hemoglobin (HbA1c) is associated with increased risk of cardiovascular disease (CVD) and mortality but little is known about potential mechanisms underlying the reported associations. Methods We used data from 1,798 non-diabetic participants from the population-based cohort Study of Health in Pomerania (SHIP) to investigate cross-sectional and longitudinal associations of HbA1c with subclinical atherosclerosis (common carotid artery intima-media thickness [CCA-IMT]), cardiac structure (left ventricular mass [LVM]), and cardiac function (fractional shortening). Results Cross-sectional analyses revealed a positive association between HbA1c and mean CCA-IMT with a 0.02 mm (95% confidence interval: 0.01–0.04) increase in CCA-IMT per 1% increase in HbA1c, and a similar positive trend across HbA1c quartiles (overall p-value <0.01). We also observed a graded association between HbA1c and high CCA-IMT (>75th percentile) with an odds ratio of 1.42 (95% CI: 1.11–1.81) per 1% increase in HbA1c. Longitudinal analyses showed no consistent associations of baseline HbA1c with mean follow-up CCA-IMT. There were no consistent associations of HbA1c with cardiac remodeling in cross-sectional and longitudinal analyses, respectively. Conclusions The association between HbA1c and CCA-IMT in non-diabetic adults may be a crucial link between high-normal HbA1c levels and an increased risk of CVD and mortality.
    No preview · Article · Sep 2014 · Diabetes Research and Clinical Practice
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    ABSTRACT: Age at menarche is a marker of timing of puberty in females. It varies widely between individuals, is a heritable trait and is associated with risks for obesity, type 2 diabetes, cardiovascular disease, breast cancer and all-cause mortality. Studies of rare human disorders of puberty and animal models point to a complex hypothalamic-pituitary-hormonal regulation, but the mechanisms that determine pubertal timing and underlie its links to disease risk remain unclear. Here, using genome-wide and custom-genotyping arrays in up to 182,416 women of European descent from 57 studies, we found robust evidence (P < 5 x 10(-8)) for 123 signals at 106 genomic loci associated with age at menarche. Many loci were associated with other pubertal traits in both sexes, and there was substantial overlap with genes implicated in body mass index and various diseases, including rare disorders of puberty. Menarche signals were enriched in imprinted regions, with three loci (DLK1-WDR25, MKRN3-MAGEL2 and KCNK9) demonstrating parent-of-origin-specific associations concordant with known parental expression patterns. Pathway analyses implicated nuclear hormone receptors, particularly retinoic acid and gamma-aminobutyric acid-B2 receptor signalling, among novel mechanisms that regulate pubertal timing in humans. Our findings suggest a genetic architecture involving at least hundreds of common variants in the coordinated timing of the pubertal transition.
    Full-text · Article · Jul 2014 · Nature
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    ABSTRACT: Background: Low total testosterone (TT) and sex hormone-binding globulin (SHBG) concentrations have been associated with the metabolic syndrome (MetS) in men, but the reported strength of association varies considerably. Objectives: We aimed to investigate whether associations differ across specific subgroups (according to age and body mass index (BMI)) and individual MetS components. Data sources: Two previously published meta-analyses including an updated systematic search in PubMed and EMBASE. Study Eligibility Criteria: Cross-sectional or prospective observational studies with data on TT and/or SHBG concentrations in combination with MetS in men. Methods: We conducted an individual participant data meta-analysis of 20 observational studies. Mixed effects models were used to assess cross-sectional and prospective associations of TT, SHBG and free testosterone (FT) with MetS and its individual components. Multivariable adjusted odds ratios (ORs) and hazard ratios (HRs) were calculated and effect modification by age and BMI was studied. Results: Men with low concentrations of TT, SHBG or FT were more likely to have prevalent MetS (ORs per quartile decrease were 1.69 (95% CI 1.60-1.77), 1.73 (95% CI 1.62-1.85) and 1.46 (95% CI 1.36-1.57) for TT, SHBG and FT, respectively) and incident MetS (HRs per quartile decrease were 1.25 (95% CI 1.16-1.36), 1.44 (95% 1.30-1.60) and 1.14 (95% 1.01-1.28) for TT, SHBG and FT, respectively). Overall, the magnitude of associations was largest in non-overweight men and varied across individual components: stronger associations were observed with hypertriglyceridemia, abdominal obesity and hyperglycaemia and associations were weakest for hypertension. Conclusions: Associations of testosterone and SHBG with MetS vary according to BMI and individual MetS components. These findings provide further insights into the pathophysiological mechanisms linking low testosterone and SHBG concentrations to cardiometabolic risk.
    Full-text · Article · Jul 2014 · PLoS ONE
  • R. Haring · K. Budde · H. Wallaschofski
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    ABSTRACT: Testosterone is the major circulating androgen in men with a physiological age-related decline in the aging male. Late-onset hypogonadism or Androgen Deficiency Syndrome (ADS) is a syndromic diagnosis including both, persistent low testosterone concentrations together with clinical symptoms including erectile dysfunction, low libido, decreased muscle mass and strength, increased body fat, decreased vitality, and depressed mood. But due to its unspecific symptoms, treatment goals, and monitoring parameters, there are many uncertainties concerning the diagnosis, therapy, and monitoring of ADS to date. The present work intends to introduce the application of metabolomics as a novel and promising tool for the improved diagnosis, therapy, and monitoring of ADS. We will outline the current uncertainties and limitations in the diagnosis and therapy of ADS to subsequently explore the scientific opportunities of metabolomics to account for the specific metabolic requirements and characteristics of the individual patient, better understand the metabolic deviations in testosterone deficiency, and monitor the biochemical changes induced by testosterone replacement therapy. We also discuss the potential of metabolomics to optimize the effectiveness and safety of individualized testosterone replacement therapy, and to thereby significantly reduce the side effects and associated health care costs of ADS treatment. © 2012 Springer Science+Business Media, LLC. All rights are reserved.
    No preview · Article · Jul 2014
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    ABSTRACT: Background: Chronic kidney disease (CKD) is a frequent, under-recognized condition and a risk factor for renal failure and cardiovascular disease. Increasing evidence connects non-alcoholic fatty liver disease (NAFLD) to CKD. We conducted a meta-analysis to determine whether the presence and severity of NAFLD are associated with the presence and severity of CKD. Methods and findings: English and non-English articles from international online databases from 1980 through January 31, 2014 were searched. Observational studies assessing NAFLD by histology, imaging, or biochemistry and defining CKD as either estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2 or proteinuria were included. Two reviewers extracted studies independently and in duplicate. Individual participant data (IPD) were solicited from all selected studies. Studies providing IPD were combined with studies providing only aggregate data with the two-stage method. Main outcomes were pooled using random-effects models. Sensitivity and subgroup analyses were used to explore sources of heterogeneity and the effect of potential confounders. The influences of age, whole-body/abdominal obesity, homeostasis model of insulin resistance (HOMA-IR), and duration of follow-up on effect estimates were assessed by meta-regression. Thirty-three studies (63,902 participants, 16 population-based and 17 hospital-based, 20 cross-sectional, and 13 longitudinal) were included. For 20 studies (61% of included studies, 11 cross-sectional and nine longitudinal, 29,282 participants), we obtained IPD. NAFLD was associated with an increased risk of prevalent (odds ratio [OR] 2.12, 95% CI 1.69-2.66) and incident (hazard ratio [HR] 1.79, 95% CI 1.65-1.95) CKD. Non-alcoholic steatohepatitis (NASH) was associated with a higher prevalence (OR 2.53, 95% CI 1.58-4.05) and incidence (HR 2.12, 95% CI 1.42-3.17) of CKD than simple steatosis. Advanced fibrosis was associated with a higher prevalence (OR 5.20, 95% CI 3.14-8.61) and incidence (HR 3.29, 95% CI 2.30-4.71) of CKD than non-advanced fibrosis. In all analyses, the magnitude and direction of effects remained unaffected by diabetes status, after adjustment for other risk factors, and in other subgroup and meta-regression analyses. In cross-sectional and longitudinal studies, the severity of NAFLD was positively associated with CKD stages. Limitations of analysis are the relatively small size of studies utilizing liver histology and the suboptimal sensitivity of ultrasound and biochemistry for NAFLD detection in population-based studies. Conclusion: The presence and severity of NAFLD are associated with an increased risk and severity of CKD. Please see later in the article for the Editors' Summary.
    Full-text · Article · Jul 2014 · PLoS Medicine
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    ABSTRACT: Background: Individualized Medicine aims at providing optimal treatment for an individual patient at a given time based on his specific genetic and molecular characteristics. This requires excellent clinical stratification of patients as well as the availability of genomic data and biomarkers as prerequisites for the development of novel diagnostic tools and therapeutic strategies. The University Medicine Greifswald, Germany, has launched the "Greifswald Approach to Individualized Medicine" (GANI_MED) project to address major challenges of Individualized Medicine. Herein, we describe the implementation of the scientific and clinical infrastructure that allows future translation of findings relevant to Individualized Medicine into clinical practice. Methods/design: Clinical patient cohorts (N > 5,000) with an emphasis on metabolic and cardiovascular diseases are being established following a standardized protocol for the assessment of medical history, laboratory biomarkers, and the collection of various biosamples for bio-banking purposes. A multi-omics based biomarker assessment including genome-wide genotyping, transcriptome, metabolome, and proteome analyses complements the multi-level approach of GANI_MED. Comparisons with the general background population as characterized by our Study of Health in Pomerania (SHIP) are performed. A central data management structure has been implemented to capture and integrate all relevant clinical data for research purposes. Ethical research projects on informed consent procedures, reporting of incidental findings, and economic evaluations were launched in parallel.
    Full-text · Article · May 2014 · Journal of Translational Medicine
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    ABSTRACT: Quantitative ultrasound of the heel captures heel bone properties that independently predict fracture risk and, with bone mineral density (BMD) assessed by x-ray (DXA), may be convenient alternatives for evaluating osteoporosis and fracture risk. We performed a meta-analysis of genome-wide association (GWA) studies to assess the genetic determinants of heel broadband ultrasound attenuation (BUA, n=14,260), velocity of sound (VOS, n=15,514) and BMD (n=4,566) in 13 discovery cohorts. Independent replication involved 7 cohorts with GWA data (in silico n=11,452) and new genotyping in 15 cohorts (de novo n=24,902). In combined random effects meta-analysis of the discovery and replication cohorts, 9 SNPs had genome-wide significant (p<5×10(-8)) associations with heel bone properties. Alongside SNPs within or near previously identified osteoporosis susceptibility genes including ESR1 (6q25.1: rs4869739, rs3020331, rs2982552), SPTBN1 (2p16.2: rs11898505), RSPO3 (6q22.33: rs7741021), WNT16 (7q31.31: rs2908007), DKK1 (10q21.1: rs7902708), and GPATCH1 (19q13.11: rs10416265), we identified a new locus on chromosome 11q14.2 (rs597319 close to TMEM135, a gene recently linked to osteoblastogenesis and longevity) significantly associated with both BUA and VOS (p<8.23×10(-14)). In meta-analyses involving 25 cohorts with up to 14,985 fracture cases, six of 10 SNPs associated with heel bone properties at p<5×10(-6) also had the expected direction of association with any fracture (p<0.05), including 3 SNPs with p<0.005: 6q22.33 (rs7741021), 7q31.31 (rs2908007), and 10q21.1 (rs7902708). In conclusion, this GWA study reveals the effect of several genes common to central DXA-derived BMD and heel ultrasound/DXA measures and points to a new genetic locus with potential implications for better understanding of osteoporosis pathophysiology.
    Full-text · Article · Jan 2014 · Human Molecular Genetics
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    ABSTRACT: Background: Anemia is an independent predictor of outcome and survival in patients with cardiovascular diseases. In contrast, data on its prognostic value among the general population is scarce and findings were limited to selected study populations. Thus, we used data from a sample of the general population with a wide age range to analyze mortality with respect to hemoglobin levels at baseline. Methods: Data from 4200 subjects (2143 women) aged 20-79 years from the population-based Study of Health in Pomerania were available. The association of serum hemoglobin with all-cause and cardiovascular mortality was estimated using multivariable Cox proportional hazards regression models and multivariable fractional polynomials. Models were adjusted for age, sex, smoking, alcohol consumption, physical inactivity, waist circumference, total/HDL-cholesterol ratio, systolic blood pressure, eGFR, and diabetes mellitus. Results: During a median follow-up of 11.3-years a total of 541 deaths occurred (180 cardiovascular cases). After full adjustment serum hemoglobin values at baseline were negatively associated with all-cause (p<.001) but not with cardiovascular mortality. Compared to subjects at median hemoglobin concentrations (8.4 mmol/l), those at the first percentile (6.4 mmol/l) had an adjusted relative risk for all-cause mortality of 1.54 (95% CI 1.18-2.00) (figure 1). After exclusion of subjects with a history of CVD or cancer and those who died within the first 12 months, there was a negative association between serum hemoglobin with both all-cause and cardiovascular that barely missed statistical significance (P=.07).
    Preview · Article · Aug 2013 · European Heart Journal
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    ABSTRACT: Low total testosterone (TT) serum concentrations in men have been associated with various cardiometabolic risk factors. But given error-prone immunoassays used for TT assessment, upcoming mass spectrometry methods question the validity of these risk associations. Thus, we performed the first comparative study quantifying potential differences in the association of TT with cardiometabolic risk factors between the two methods. We used data from 1,512 men aged 20-81 years, recruited for the cross-sectional population-based Study of Health in Pomerania (SHIP), Germany. TT was repeatedly measured by chemiluminescent immunoassay (CLIA, Immulite 2500) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). We tested for significant differences between coefficients from CLIA- and LC-MS/MS-based multiple linear regression models associating TT with major cardiometabolic risk factors including adiposity, lipid metabolism, blood pressure, diabetic status, and inflammation. TT measurements by CLIA and LC-MS/MS yielded a Pearson correlation coefficient of 0.84. Only three of the ten tested associations for TT with cardiometabolic risk factor showed significant differences between the two measurement methods: in comparison to LC-MS/MS, CLIA-based TT assessment significantly underestimated risk associations of TT with waist circumference (ß: -0.54 vs. -0.63), body mass index (ß: -0.19 vs. -0.22), and ln-glucose levels (ß: -0.006 vs. -0.008). In the present comparative study, the CLIA platform showed a reasonable measurement error and yielded comparable risk associations, providing little support to measure TT concentrations in men from the general population exclusively by LC-MS/MS.
    Preview · Article · Jul 2013 · European Journal of Endocrinology
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    ABSTRACT: Previous research has suggested a positive association between testosterone (T) and entrepreneurial behavior in males. However, this evidence was found in a study with a small sample size and has not been replicated. In the present study, we aimed to verify this association using two large, independent, population-based samples of males. We tested the association of T with entrepreneurial behavior, operationalized as self-employment, using data from the Rotterdam Study (N = 587) and the Study of Health in Pomerania (N = 1,697). Total testosterone (TT) and sex hormone-binding globulin (SHBG) were measured in the serum. Free testosterone (FT), non-SHBG-bound T (non-SHBG-T), and the TT / SHBG ratio were calculated and used as measures of bioactive serum T, in addition to TT adjusted for SHBG. Using logistic regression models, we found no significant associations between any of the serum T measures and self-employment in either of the samples. To our knowledge, this is the first large-scale study on the relationship between serum T and entrepreneurial behavior.
    Full-text · Article · Jun 2013 · Physiology & Behavior
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    ABSTRACT: : The association between sex hormones and blood pressure (BP) in women has been investigated mostly in cross-sectional studies yielding inconsistent results. : Data from 1428 women from the population-based Study of Health in Pomerania were used. Associations of total testosterone, androstenedione, sex hormone-binding globulin (SHBG), and free testosterone concentrations with BP and hypertension were analyzed in multivariable cross-sectional and longitudinal regression models in the full sample and stratified by menopausal status. : A positive association between total testosterone and BP was revealed in the full sample [SBP: β per standard deviation (SD) increase: 3.22; pulse pressure (PP): β per SD increase: 2.30] and among postmenopausal women (DBP: β per SD increase: 3.33; SBP: β per SD increase: 7.11; PP: β per SD increase: 3.77). Longitudinal analyses also showed a positive association between baseline total testosterone and follow-up BP. Furthermore, low total testosterone concentrations were associated with a decreased risk of prevalent hypertension in all women [relative risk (RR) quartile 1 (Q1) vs. Q4, 0.79; 95% confidence interval, CI 0.67-0.94]. Low SHBG was associated with prevalent hypertension in postmenopausal women (RR 1.27; 95% CI 1.06-1.53) and with incident hypertension in the full sample (RR 1.73; 95% CI 1.10-2.75). : The present population-based study is the first to show a consistent positive association between total testosterone and BP in both, cross-sectional and longitudinal analyses, suggesting high total testosterone as a risk marker of increased BP, as well as prevalent hypertension in women.
    No preview · Article · Jun 2013 · Journal of Hypertension
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    ABSTRACT: Background To investigate potential associations of serum prolactin concentration (PRL) with metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM), previously observed in small and selected study samples, in a large population-based cohort. Methods Data from 3,993 individuals (2,027 women) aged 20-79 years from the population-based Study of Health of Pomerania (SHIP) were used to analyse cross-sectional and longitudinal associations of PRL with MetS and T2DM risk in age- and multivariable-adjusted Poisson regression models. PRL were log-transformed and modelled as continuous (per standard deviation (SD) increase) and categorical predictor (sex-specific quartiles) variable, separately for men and woman. Results Cross-sectional analyses showed an inverse association between low PRL concentrations and prevalent T2DM risk in men and women after multivariable-adjustment (men: Q1 vs. Q4: relative risk (RR), 1.55; 95% confidence interval (CI), 1.13 – 2.14; women: Q1 vs. Q4: RR, 1.70; 95% CI, 1.10 – 2.62). Likewise, higher PRL concentrations were associated with significantly lower T2DM risk (RR per SD increase in log-PRL: 0.83; 95% CI, 0.72 – 0.95 in men, and 0.84; 95% CI, 0.71 – 0.98 in women, respectively). An inverse association between PRL and MetS risk was not retained after multivariable adjustment. Longitudinal analyses yielded no association of PRL with incident MetS or T2DM. Conclusion The present study is the first large population-based study reporting a cross-sectional inverse association between PRL and prevalent T2DM in both genders. But the absent longitudinal associations do not support a causal role of PRL as a risk factor of incident MetS or T2DM.
    Full-text · Article · Mar 2013 · BMC Endocrine Disorders
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    ABSTRACT: Prospective studies showed that low serum testosterone concentrations are associated with various cardiometabolic risk factors and mortality. However, the causal nature of these associations is controversial. We studied 1 882 men aged 20-79 years with serum testosterone concentrations and genotyping data from the longitudinal population-based Study of Health in Pomerania. Testosterone concentrations were cross-sectionally associated with cardiometabolic risk factors, including anthropometric, lipid, blood pressure and glycaemic parameters; and prospectively with all-cause mortality (277 deaths, 14.7%) during the 10-year follow-up. To overcome problems of residual confounding, reverse causation, or regression dilution bias in the investigated testosterone-outcome associations, we used two-stage least square regression models with previously identified polymorphisms at the SHBG gene (rs12150660) and X chromosome (rs5934505) as multiple genetic instruments in an instrumental variable (IV) approach, also known as Mendelian randomization. In standard regression analyses, testosterone was robustly associated with a wide range of cardiometabolic risk factors. In subsequent IV analyses, no such significant associations were observed. Similarly, prospective analyses showed a consistent association of low testosterone concentrations with increased all-cause mortality risk, which was not apparent in subsequent IV analyses. The present Mendelian randomization analyses did not detect any evidence for causal associations of testosterone concentrations with cardiometabolic risk factors and mortality, suggesting that previously reported associations might largely result from residual confounding or reverse causation. Although testosterone assessment might improve risk prediction, implementation of testosterone replacement therapy requires further evidence of a direct effect on cardiometabolic outcomes from double-blinded randomized controlled trials and large-scale Mendelian randomization meta-analyses.
    Full-text · Article · Mar 2013 · Andrology
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    ABSTRACT: Research in the last decade has revealed that bone is not only a target tissue for numerous circulating hormones but functions as an endocrine organ itself. As a recent study demonstrated a stimulatory effect of the osteoblast-derived hormone osteocalcin (OCN) on testosterone production in mice, we investigated whether such an association can be replicated in humans. We used data from 1338 men (25-86 years) in the population-based epidemiological Study of Health in Pomerania and from 110 male outpatients with bone disorders (18-85 years) for the study. We analysed cross-sectional associations between OCN and total testosterone serum concentrations (TT), as well as associations between further markers of bone turnover [bone-specific alkaline phosphatase (BAP), serum C-terminal telopeptides of Type I collagen (CTX), urinary deoxypyridinoline] and TT using ordinary least square (OLS) regression models. Multivariable OLS models revealed a positive association between OCN and TT in the population-based (β coefficients for a one standard deviation increase, 0.590; standard error (SE), 0.175; p-value, <0.01) and patient-based (β coefficient, 0.575; SE, 0.132; p-value, <0.01) samples even after adjustment for age and body mass index (both samples), and time of blood sampling (population-based sample only). Furthermore, we observed positive associations between BAP and TT (β coefficient, 0.403; SE, 0.170; p-value, 0.02) as well as between CTX and TT (β coefficient, 0.733; SE, 0.172; p-value, <0.01) in men from the general population. The present investigation shows that OCN is associated with TT in the general population and in patients with bone disorders, and may thus indicate general male health status. Additional longitudinal observational studies are warranted to confirm our findings and future experimental research is necessary to elucidate potential mechanisms underlying the observed associations.
    No preview · Article · Jan 2013 · Andrology
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    ABSTRACT: Background: Across the industrialized world, men experience an earlier onset of cardiovascular disease (CVD) and a life expectancy 5 to 10 years shorter than women. Low total testosterone (TT) concentrations in men have been suggested as a novel CVD risk factor, but its contribution to this gender gap is less well studied. Methods: We used data of 4152 individuals (2113 women and 2039 men) aged 20 to 79 years from the longitudinal population-based cohort Study of Health in Pomerania, Germany. Multivariable Poisson and Cox proportional hazard regression models were used to investigate the risk of incident cardiovascular morbidity (5-year examination follow-up), as well as all-cause and CVD mortality (10-year follow-up) between men and women. Additionally, the added risk attributable to low TT in men (<10th percentile) was assessed. Results: Compared with women, men were uniformly at higher risk of incident cardiovascular morbidity, including overweight, hypertension, dyslipidemia, metabolic syndrome, and type 2 diabetes mellitus. Men were also at increased all-cause mortality (hazard ratio = 2.05; 95% CI, 1.61-2.60) and 10-year CVD risk compared with women. In subgroup analyses, men with low TT showed the highest 10-year CVD and mortality risk compared with both men with higher TT and women. TT was also negatively associated with cardiovascular risk as defined by the Framingham risk score (P < 0.001), after multivariable adjustment. Conclusions: Analyzing a large population-based sample, we observed that men have a generally higher risk of incident cardiovascular morbidity and mortality. Furthermore, men with low TT concentrations were identified as high-risk individuals with regard to 10-year CVD and mortality risk.
    No preview · Article · Nov 2012 · Gender Medicine
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    ABSTRACT: Dehydroepiandrosterone (DHEA) is the major precursor of human sex steroid synthesis and is inactivated via sulfonation to DHEAS. A previous genome-wide association study (GWAS) associated the single nucleotide polymorphism (SNP) rs2637125, located near the coding region of DHEA sulfotransferase, SULT2A1, with serum DHEAS concentrations. However, the functional relevance of this SNP with regard to DHEA sulfonation is unknown. Using data from 3,300 participants of the population-based cohort Study of Health in Pomerania (SHIP), we identified 43 individuals being homozygote for the minor allele of the SNP rs2637125 (AA), and selected two sex- and age-matched individuals with AG and GG genotype (N=172), respectively. Steroid analysis including measurement of serum DHEA and DHEAS was carried out by liquid chromatography/mass spectrometry, employing steroid oxime analysis for enhancing the sensitivity of DHEA detection. We applied quantile regression models to compare median hormone levels across SULT2A1 genotypes. Median comparisons by SULT2A1 genotype (AA vs. AG and GG genotypes, respectively) showed no differences in the considered hormones including DHEAS, DHEA, androstenedione, as well as cortisol and cortisone concentrations. SULT2A1 genotype also had no effect on the DHEA/DHEAS ratio. Sex-stratified analyses, as well as alternative use of the SULT2A1 SNP rs182420 yielded similar negative results. Genetic variants of SULT2A1 do not appear to have an effect on individual DHEA and DHEAS concentrations or the DHEA/DHEAS ratio as a marker of DHEA sulfonation capacity.
    Full-text · Article · Nov 2012 · Journal of Molecular Endocrinology

Publication Stats

2k Citations
408.11 Total Impact Points

Institutions

  • 2007-2015
    • University of Greifswald
      • • Institute of Clinical Chemistry and Laboratory Medicine
      • • Institute of Biochemistry
      • • Center for Internal Medicine
      • • Institute of Community Medicine
      Griefswald, Mecklenburg-Vorpommern, Germany
  • 2012
    • Boston University
      • Section of Preventive Medicine and Epidemiology
      Boston, Massachusetts, United States