Steve Nguyen

University of California, San Diego | UCSD · Herbert Wertheim School of Public Health and Human Longevity Science

Objective The American Heart Association’s Life’s Essential 8 (LE8) metric includes self-reported physical activity as one of the metrics for assessing cardiovascular health. Self-reported physical activity is prone to misclassification, whereas accelerometer measures are less biased. We examined associations of LE8 and incident cardiovascular dise...

Background and objectives: Epigenetic age estimators indicating faster/slower biological aging vs chronological age independently associate with several age-related outcomes; however, longitudinal associations with cognitive function are understudied. We examined associations of epigenetic age estimators with cognitive function measured annually....

Background Sedentary behavior is a recognized mortality risk factor. The novel and validated convolutional neural network hip accelerometer posture algorithm highly accurately classifies sitting and postural changes compared with accelerometer count cut points. We examined the prospective associations of convolutional neural network hip acceleromet...

Importance Heart failure (HF) prevention is paramount to public health in the 21st century. Objective To examine incident HF and its subtypes with preserved ejection fraction (HFpEF) and reduced EF (HFrEF) according to accelerometer-measured physical activity (PA) and sedentary time. Design, Setting, and Participants This was a prospective cohort...

Background Epigenetic age acceleration (AgeAccel) indicates faster biological aging relative to chronological age and has been independently associated with several age‐related outcomes. However, the cross‐sectional and longitudinal associations of AgeAccel with global cognitive function is understudied. Method We therefore studied 734 women (mean...

Introduction: Sedentary behavior (SB) is a recognized mortality and CVD risk factor. Most studies with accelerometry classified SB using cut-points, which do not capture postural transitions as accurately as thigh-worn devices. The recently published convolutional neural network hip accelerometer posture (CHAP) algorithm more accurately classifies...

Introduction: Physical activity (PA) is prospectively inversely associated with dementia risk, but few studies examined accelerometer measures of PA and sitting with rigorously-adjudicated mild cognitive impairment (MCI) and dementia risk. Methods: We examined the associations of accelerometer measures (PA and sitting) with incident MCI/probable...

Psychological well-being is linked to healthy aging in older women, but associations with health behaviors are not well understood. Our study aims to evaluate the relationships between objectively-measured physical behavior (including physical activity and sedentary behavior) with optimism and positive affect in a diverse sample of older women. Our...

Purpose: Our study evaluated the agreement of mean daily step counts, peak 1-min cadence, and peak 30-min cadence between the hip-worn ActiGraph GT3X+ accelerometer, using the normal filter (AGN) and the low frequency extension (AGLFE), and the thigh-worn activPAL3 micro (AP) accelerometer among older adults. Methods: Nine-hundred and fifty-thre...

DNA methylation (DNAm) has been reported to be associated with many diseases and with mortality. We hypothesized that the integration of DNAm with clinical risk factors would improve mortality prediction. We performed an epigenome-wide association study of whole blood DNAm in relation to mortality in 15 cohorts (n = 15,013). During a mean follow-up...

Introduction: The AHA’s Life’s Simple 7 (LS7) includes physical activity (PA) as one of the metrics for assessing cardiovascular health. Using self-reported PA can misclassify those who meet the PA component of the LS7. Using accelerometer-measured PA may improve the utility of the LS7. Our study compares associations of LS7 and incident cardiovasc...

Background Current physical activity guidelines focus on volume and intensity for CVD prevention rather than common behaviors responsible for movement, including those for daily living activities. We examined the associations of a machine‐learned, accelerometer‐measured behavior termed daily life movement (DLM) with incident CVD. Methods and Resul...

Importance: Social isolation and loneliness are increasing public health concerns and have been associated with increased risk of cardiovascular disease (CVD) among older adults. Objective: To examine the associations of social isolation and loneliness with incident CVD in a large cohort of postmenopausal women and whether social support moderat...

DNA methylation (DNAm) has been reported to be associated with many diseases and mortality. We hypothesized that the integration of DNAm with clinical risk factors would improve mortality prediction.We performed an epigenome-wide association study of whole blood DNAm in relation to mortality in 15 cohorts (n=15,013). During a mean follow-up of 10 y...

Women aged 65 and older experience nearly three-fourths of the 2 million osteoporotic fractures annually in the US, yet whether accelerometer-measured volumes and intensities of physical activity and sedentary behavior (SB) are associated with reduced fracture risk is understudied. We investigated associations of accelerometer-measured light physic...

Background: Body mass index (BMI), a well-known risk factor for poor cardiovascular outcomes, is associated with differential DNA methylation (DNAm). Similarly, metabolic health has also been associated with changes in DNAm. It is unclear how overall metabolic health outside of BMI may modify the relationship between BMI and methylation profiles,...

Objectives: Electronic health records (EHR) are a convenient data source for clinical trial recruitment and allow for inexpensive participant screening. However, EHR may lack pertinent screening variables. One strategy is to identify surrogate EHR variables which can predict the screening variable of interest. In this article, we use BMI to develo...

Objective: Reduced functional capacity is a hallmark of early pre-clinical stages of heart failure (HF). The Short Physical Performance Battery (SPPB) is a valid measure of lower extremity physical function, has relatively low implementation burden, and is associated with cardiovascular disease and mortality. However, the SPPB-HF association is un...

Background: DNA methylation patterns associated with habitual diet have not been well studied. Methods: Diet quality was characterized using a Mediterranean-style diet score and the Alternative Healthy Eating Index score. We conducted ethnicity-specific and trans-ethnic epigenome-wide association analyses for diet quality and leukocyte-derived D...

Introduction: DNA methylation age acceleration (DNAmAA) scores, which are epigenetic biomarkers of aging and physiological responses to environmental factors such as lifestyle and health behaviors, have been previously shown to be associated with cardiovascular disease (CVD) outcomes and all-cause mortality. Life’s Simple 7 (LS7) is a tool promoted...

Background/Objectives: There is increasing evidence of a relationship between blood DNA methylation and body mass index (BMI). We aimed to assess associations of BMI with individual methylation measures (CpGs) through a cross-sectional genome-wide DNA methylation association study and a longitudinal analysis of repeated measurements over time. Sub...

Background: Epigenetic modifications such DNA methylation variation comprise a potentially useful new class of biomarkers that may improve coronary heart disease (CHD) risk stratification, or better capture early pathophysiological processes. However, replicated associations of DNA methylation and CHD are few, and existing studies are primarily cro...