High sleep variability predicts a blunted weight loss response and short sleep duration a reduced decrease in waist circumference in the PREDIMED-Plus Trial.

BACKGROUND: Whether short sleep duration or high sleep variability may predict less weight loss and reduction in measures of adiposity in response to lifestyle interventions is unknown. The aim of this study was to compare the 12-month changes in weight and adiposity measures between those participants with short or adequate sleep duration and those with low or high sleep variability (intra-subject standard deviation of the sleep duration) in PREvención con DIeta MEDiterránea (PREDIMED)-Plus, a primary prevention trial based on lifestyle intervention programs. METHODS: Prospective analysis of 1986 community-dwelling subjects (mean age 65 years, 47% females) with overweight/obesity and metabolic syndrome from the PREDIMED-Plus trial was conducted. Accelerometry-derived sleep duration and sleep variability and changes in average weight, body mass index (BMI), and waist circumference (WC) attained after 12-month interventions were analyzed. RESULTS: The adjusted difference in 12-month changes in weight and BMI in participants in the third tertile of sleep variability was 0.5 kg (95% CI 0.1 to 0.9; p = 0.021) and 0.2 kg/m2 (0.04 to 0.4; p = 0.015), respectively, as compared with participants in the first tertile. The adjusted difference in 12-month changes from baseline in WC was -0.8 cm (-1.5 to -0.01; p = 0.048) in participants sleeping <6 h, compared with those sleeping between 7 and 9 h. CONCLUSIONS: Our findings suggest that the less variability in sleep duration or an adequate sleep duration the greater the success of the lifestyle interventions in adiposity.

Long Daytime Napping Is Associated with Increased Adiposity and Type 2 Diabetes in an Elderly Population with Metabolic Syndrome.

Research examining associations between objectively-measured napping time and type 2 diabetes (T2D) is lacking. This study aimed to evaluate daytime napping in relation to T2D and adiposity measures in elderly individuals from the Mediterranean region. A cross-sectional analysis of baseline data from 2190 elderly participants with overweight/obesity and metabolic syndrome, in the PREDIMED-Plus trial, was carried out. Accelerometer-derived napping was measured. Prevalence ratios (PR) and 95% confidence intervals (CI) for T2D were obtained using multivariable-adjusted Cox regression with constant time. Linear regression models were fitted to examine associations of napping with body mass index (BMI) and waist circumference (WC). Participants napping ≥90 min had a higher prevalence of T2D (PR 1.37 (1.06, 1.78)) compared with those napping 5 to <30 min per day. Significant positive associations with BMI and WC were found in those participants napping ≥30 min as compared to those napping 5 to <30 min per day. The findings of this study suggest that longer daytime napping is associated with higher T2D prevalence and greater adiposity measures in an elderly Spanish population at high cardiovascular risk.

Sleep Duration is Inversely Associated with Serum Uric Acid Concentrations and Uric Acid to Creatinine Ratio in an Elderly Mediterranean Population at High Cardiovascular Risk.

The aim of the study was to evaluate sleep duration and sleep variability in relation to serum uric acid (SUA) concentrations and SUA to creatinine ratio. This is a cross-sectional analysis of baseline data from 1842 elderly participants with overweight/obesity and metabolic syndromein the (Prevención con Dieta Mediterránea) PREDIMED-Plus trial. Accelerometry-derived sleep duration and sleep variability were measured. Linear regression models were fitted to examine the aforementioned associations. A 1 hour/night increment in sleep duration was inversely associated with SUA concentrations (ß = 0.07, p = 0.047). Further adjustment for leukocytes attenuated this association (p = 0.050). Each 1-hour increment in sleep duration was inversely associated with SUA to creatinine ratio (ß = 0.15, p = 0.001). The findings of this study suggest that longer sleep duration is associated with lower SUA concentrations and lower SUA to creatinine ratio.

Demographic and Social-Cognitive Factors Associated with Weight Loss in Overweight, Pre-diabetic Participants of the PREVIEW Study.

PURPOSE: Weight loss has been demonstrated to be a successful strategy in diabetes prevention. Although weight loss is greatly influenced by dietary behaviors, social-cognitive factors play an important role in behavioral determination. This study aimed to identify demographic and social-cognitive factors (intention, self-efficacy, outcome expectancies, social support, and motivation with regard to dietary behavior and goal adjustment) associated with weight loss in overweight and obese participants from the PREVIEW study who had pre-diabetes. METHOD: Prospective correlational data from 1973 adult participants were analyzed. The participants completed psychological questionnaires that assessed social-cognitive variables with regard to dietary behavior. Stepwise multiple regression analyses were performed to identify baseline demographic and social-cognitive factors associated with weight loss. RESULTS: Overall, being male, having a higher baseline BMI, having a higher income, perceiving fewer disadvantages of a healthy diet (outcome expectancies), experiencing less discouragement for healthy eating by family and friends (social support), and lower education were independently linked to greater weight loss. When evaluating females and males separately, education was no longer associated with weight loss. CONCLUSION: The results indicate that a supportive environment in which family members and friends avoid discouraging healthy eating, with the application of a strategy that uses specific behavior change techniques to emphasize the benefits of outcomes, i.e., the benefits of a healthy diet, may support weight loss efforts. Weight loss programs should therefore always address the social environment of persons who try to lose body weight because family members and friends can be important supporters in reaching a weight loss goal.

Cardiovascular risk factors in young, overweight, and obese European adults and associations with physical activity and omega-3 index.

Excess body fat is associated with increased cardiovascular disease (CVD) risk. The hypothesis of the study was that physical activity and omega-3 index, a marker of past long chain n-3 polyunsaturated fatty acids consumption, counteract the negative associations between fatness and CVD risk factors in young overweight and obese adults. A total of 324 subjects (20-40 years, body mass index [BMI], 27.5-32.5 kg/m(2), from Iceland, Spain, and Ireland) were investigated cross-sectionally. Dietary intake, anthropometric measurements, blood pressure, CVD risk factors, and fatty acids in erythrocyte membrane were analyzed. Information on physical activity was collected. Linear models were constructed to find out the associations of BMI, physical activity (quartiles), and omega-3 index with CVD risk factors. The most frequently increased risk factors were blood lipids (41.4%) and blood pressure (32.1%); fewer participants experienced disturbed glucose metabolism (11.8%). Body mass index was significantly associated with increased CVD risk factors (P = .001-.029), with the exception of total cholesterol, low-density lipoprotein, and high-density lipoprotein. The highest physical activity quartile had a lower fat mass (P = .005, at a given BMI), leptin (P = .008, in male participants only), and interleukin 6 (P = .021) but higher high-density lipoprotein (P = .020) than other quartiles; however, an approximate dose-response relationship could only be observed for leptin. The omega-3 index was not associated with lower low-density lipoprotein (P = .056), but docosahexaenoic acid in erythrocyte membrane was associated to it (P = .016). It is concluded that physical activity and docosahexaenoic acid diminish some of the negative health effects associated with overweight and obesity; however, body fatness remains the most important variable associated with increased CVD risk factors in young overweight and obese adults.