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Background: Income volatility is on the rise and presents a growing public health problem. Because in many epidemiological studies income is measured at a single point in time, the association of long-term income volatility with incident cardiovascular disease (CVD) and mortality has not been adequately explored. The goal of this study was to examine associations of income volatility from 1990 to 2005 with incident CVD and all-cause mortality in the subsequent 10 years., Methods: The Coronary Artery Risk Development in Young Adults Study is an ongoing prospective cohort study conducted within urban field centers in Birmingham, AL; Chicago, IL; Minneapolis, MN; and Oakland, CA. We studied 3937 black and white participants 23 to 35 years of age in 1990 (our study baseline). Income volatility was defined as the intraindividual SD of the percent change in income across 5 assessments from 1990 to 2005. An income drop was defined as a decrease of ≥25% from the previous visit and less than the participant's average income from 1990 to 2005. CVD events (fatal and nonfatal) and all-cause mortality between 2005 and 2015 were adjudicated with the use of medical records and death certificates. CVD included primarily acute events related to heart disease and stroke., Results: A total of 106 CVD events and 164 deaths occurred between 2005 and 2015 (incident rate, 2.76 and 3.66 per 1000 person-years, respectively). From Cox models adjusted for sociodemographic, behavioral, and CVD risk factors, higher income volatility and more income drops were associated with greater CVD risk (high versus low volatility: hazard ratio, 2.07; 95% CI, 1.10-3.90; ≥2 versus 0 income drops: hazard ratio, 2.54; 95% CI, 1.24-5.19) and all-cause mortality (high versus low volatility: hazard ratio, 1.78; 95% CI,1.03-3.09; ≥2 versus 0 income drops: hazard ratio, 1.92; 95% CI, 1.07-3.44)., Conclusions: In a cohort of relatively young adults, income volatility and drops during a 15-year period of formative earning years were independently associated with a nearly 2-fold risk of CVD and all-cause mortality.

Background: Excessive sedentary time is ubiquitous in developed nations and is associated with deleterious health outcomes. Few studies have examined whether the manner in which sedentary time is accrued (in short or long bouts) carries any clinical relevance. The purpose of this study was to examine the association of prolonged, uninterrupted sedentary behavior with glycemic biomarkers in a cohort of US Hispanic/Latino adults., Methods: We studied 12 083 participants from the HCHS/SOL (Hispanic Community Health Study/Study of Latinos), a population-based study of Hispanic/Latino adults 18 to 74 years of age. Homeostatic model assessment of insulin resistance and glycosylated hemoglobin were measured from a fasting blood sample, and 2-hour glucose was measured after an oral glucose tolerance test. Sedentary time was objectively measured with a hip-mounted accelerometer. Prolonged, uninterrupted sedentariness was expressed as mean sedentary bout length., Results: After adjustment for potential confounders and moderate to vigorous physical activity, longer sedentary bout duration was dose-dependently associated with increased homeostatic model assessment of insulin resistance ( P for trend<0.001) and 2-hour glucose levels ( P for trend=0.015). These associations were not independent of total sedentary time; however, a significant interaction between sedentary bout duration and total sedentary time was observed. Evaluation of the joint association of total sedentary time and sedentary bout duration showed that participants in the upper quartile for both sedentary characteristics (ie, high total sedentary time and high sedentary bout duration) had the highest levels of homeostatic model assessment of insulin resistance ( P <0.001 versus low group for both sedentary characteristics) and 2-hour glucose ( P =0.002 versus low group for both sedentary characteristics). High total sedentary time or high sedentary bout duration alone were not associated with differences in any glycemic biomarkers., Conclusions: Accruing sedentary time in prolonged, uninterrupted bouts may be deleteriously associated with biomarkers of glucose regulation., (© 2017 American Heart Association, Inc.)