Obesity-related risk factors of cardiovascular disease

Diet and body fat in adolescence and early adulthood: a systematic review of longitudinal studies

Adipose tissue is a vital component of the human body, but in excess, it represents a risk to health. According to the World Health Organization, one of the main factors determining excessive body adiposity is the dietary habit. This systematic review investigated longitudinal studies that assessed the association between diet and body fat in adolescents and young adults. Twenty-one relevant papers published between 2001 and 2015 were selected. The most used method for estimating body fat was the body mass index (15 studies). Diet was most commonly assessed by estimating the consumption of food groups (cereals, milk and dairy products) and specific foods (sugar-sweetened beverages, soft drinks, fast foods, milk, etc.). Ten studies found a direct association between diet and quantity of body fat. During adolescence, adhering to a dietary pattern characterized by high consumption of energy-dense food, fast foods, sugar-sweetened beverages and soft drinks, as well as low fiber intake, appears to contribute to an increase in body fat in early adulthood. The findings of the present study suggest that the frequent consumption of unhealthy foods and food groups (higher energy density and lower nutrient content) in adolescence is associated with higher quantity of body fat in early adulthood.

LDL cholesterol was more strongly associated with percent body fat than body mass index and waist circumference in a health screening population

AIMS

To compare correlations between changes in cardiovascular risk factors and those in obesity indices and to compare associations with incident hyper-LDL cholesterolemia among obesity indices.

METHODS

Correlation coefficients were calculated between 7-year changes in cardiovascular risk factors and those in body mass index (BMI), waist circumference (WC) and percent body fat (PBF) in 634 men and 396 women who used no antihypertensive, antidiabetic or antihyperlipidemic drugs. Odds ratios of incident hyper-LDL cholesterolemia after 7 years were calculated for BMI, WC and PBF in 738 men and 388 women.

RESULTS

There were no significant differences in the correlations with 7-year changes in cardiovascular risk factors between 7-year changes in BMI and WC. The correlation with 7-year change in LDL cholesterol was stronger for that in PBF than that in BMI or WC (p=0.021 or 0.089, respectively in men and 0.022 or 0.020, respectively in women). The correlations with 7-year changes in log triglycerides, HDL cholesterol and log high-sensitivity CRP were stronger for those in BMI and WC than that in PBF in men. Incident hyper-LDL cholesterolemia after 7 years was significantly associated with PBF, but not BMI or WC, in men after adjusted for age and other covariates. However, the association was not significant after further adjusted for LDL cholesterol.

CONCLUSIONS

The correlation with 7-year change in LDL cholesterol was stronger for that in PBF than that in BMI or WC. Incident hyper-LDL cholesterolemia was significantly associated with PBF, but not with BMI or WC, in men.

Relationship Between Measures of Adiposity, Arterial Inflammation, and Subsequent Cardiovascular Events

BACKGROUND

The objective of this study was to evaluate how different measures of adiposity are related to both arterial inflammation and the risk of subsequent cardiovascular events.

METHODS AND RESULTS

We included individuals who underwent (18)F-fluorodeoxyglucose positron emission tomography/computed tomography imaging for oncological evaluation. Subcutaneous adipose tissue (SAT) volume, visceral adipose tissue (VAT) volume, and VAT/SAT ratio were determined. Additionally, body mass index, metabolic syndrome, and aortic (18)F-fluorodeoxyglucose uptake (a measure of arterial inflammation) were determined. Subsequent development of cardiovascular disease (CVD) events was adjudicated. The analysis included 415 patients with a median age of 55 (P25-P75: 45-65) and a median body mass index of 26.4 (P25-P75: 23.4-30.9) kg/m(2). VAT and SAT volume were significantly higher in obese individuals. VAT volume (r=0.290; P<0.001) and VAT/SAT ratio (r=0.208; P<0.001) were positively correlated with arterial inflammation. Thirty-two subjects experienced a CVD event during a median follow-up of 4 years. Cox proportional hazard models showed that VAT volume and VAT/SAT ratio were associated with CVD events (hazard ratio [95% confidence interval]: 1.15 [1.06-1.25]; P<0.001; 3.60 [1.88-6.92]; P<0.001, respectively). Body mass index, metabolic syndrome, and SAT were not predictive of CVD events.

CONCLUSIONS

Measures of visceral fat are positively related to arterial inflammation and are independent predictors of subsequent CVD events. Individuals with higher measures of visceral fat as well as elevated arterial inflammation are at highest risk for subsequent CVD events. The findings suggest that arterial inflammation may explain some of the CVD risk associated with adiposity.

Vitamin D Levels and Markers of Inflammation and Metabolism in HIV-Infected Individuals on Suppressive Antiretroviral Therapy

Data on vitamin D insufficiency as a cause of inflammation and metabolic dysfunction in HIV-infected individuals are conflicting. We examined the relationships between levels of 25-hydroxyvitamin D [25(OH)D] and biomarkers of inflammation and metabolism in stored blood samples from a prospective trial of vitamin D repletion. Blood samples from HIV-infected individuals on antiretroviral therapy (ART) with HIV-1 RNA <200 copies/ml enrolled in a prospective study were analyzed for 25(OH)D levels, a broad panel of cytokines, highly sensitive C-reactive protein, D-dimer, adiponectin, leptin, and insulin. Correlations between markers and 25(OH)D levels were determined. The Wilcoxon Rank Sum test was used to compare markers between individuals 25(OH)D insufficient and sufficient at baseline and before and after repletion among those who were insufficient and repleted to ≥30 ng/ml after 12 weeks. Of 106 subjects with stored plasma [66 with 25(OH)D <30 ng/ml and 40 ≥ 30 ng/ml], the median age was 50, the CD4 count was 515 cells/mm(3), 94% were male, and the median baseline 25(OH)D was 27 ng/ml. Higher 25(OH)D levels were associated with lower tumor necrosis factor (TNF)-α (r = -0.20, p = 0.04) and higher adiponectin levels (r = 0.30, p = 0.002). Following successful repletion to 25(OH)D ≥30 ng/ml there were no significant changes in inflammatory or metabolic parameters. Our study found associations between low 25(OH)D levels and TNF-α and adiponectin. Repletion did not result in changes in markers of inflammation or metabolism. These data support continued study of the relationship between vitamin D, inflammation, and metabolism in treated HIV infection.

Association between Vitamin D and Adiponectin and Its Relationship with Body Mass Index: The META-Health Study

Background: Low vitamin D and adiponectin levels are both associated with obesity and cardiovascular disease. Previous studies have indicated that vitamin D levels are directly associated with adiponectin, and that this association varies across body mass index (BMI) categories; stronger with increasing BMI. Few studies examined this association in African-Americans (AA), known to have lower levels of vitamin D and adiponectin, and in whites.

Methods: We assessed whether serum vitamin D is associated with serum adiponectin in a biracial population-based sample. Cross-sectional analyses were performed on 426 non-diabetic participants (218 whites and 208 AA) from the META-Health Study, a random sample from the metro Atlanta. Age-adjusted correlations and multivariable linear regression were used for analyses. We investigated the effect modification of the BMI categories of lean, overweight, and obese as defined by standard cut-points (25 and 30 kg/m²).

Results: The mean (SD) age of our study sample was 50.5 (9) years. The mean (SD) levels of vitamin D were 27.4 (9.8) ng/mL in white women, 25.5 (9.3) ng/mL in white men, 16.9 (7.3) ng/mL in AA women, and 18.8 (7.3) ng/mL in AA men. The mean (SD) levels of adiponectin were 17.0 (17.1) μg/mL in white women, 9.9 (11.3) μg/mL in white men, 6.6 (4.8) μg/mL in AA women, and 9.4 (11.6) μg/mL in AA men. Among lean white women (n = 63), there was a significant direct association between vitamin D and adiponectin (β = 0.02, p = 0.04) after adjustment for age, systolic blood pressure, HDL-cholesterol, triglycerides, income, and season of blood drawing. On the contrary, in lean AA women (n = 23), there was a significant inverse association (β = −0.06, p = 0.01).

Conclusion: The association of vitamin D and adiponectin is dependent on race, gender, and BMI category. Among lean white women, there was a significant direct association, whereas in lean AA women the association was inverse. No association was present among obese individuals.

Association of alcohol consumption with the impaired β-cell function independent of body mass index among Chinese men

Alcohol consumption is associated with type 2 diabetes. However, the relationship between alcohol consumption and β-cell function is still unclear. The aim of this study is to investigate the association between them. 675 Chinese men aged 20-75 years were recruited. The subjects were first classified into never drinkers, abstainers, light drinkers (0.1-19.9 g/day) , moderate drinkers (20.0-39.9 g/day) and heavy drinkers (≥ 40.0 g/day) and then, were further divided into two subgroups according to body mass index (BMI) (BMI<25kg/m² and BMI ≥ 25kg/m²). Analysis procedure was adjusted by the confounders including age, smoking status, BMI, waist circumference (WC), blood pressure, lipids and blood uric acid. Compared with never drinkers, alcohol consumption was associated with decreased homeostasis model assessment of β-cell function (HOMA-β) independent of BMI. The homeostasis model assessment of insulin resistance (HOMA-IR) was significantly correlated with alcohol consumption history in the group of BMI<25kg/m² and was significantly correlated with alcohol consumption in the group of BMI ≥ 25kg/m². The results suggest that alcohol consumption is associated with the β-cell dysfunction independent of BMI in Chinese community dwelling men.