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Background: Studies have found that HDL particle (HDL-P) concentration is inversely associated with risk of CVD, independent of HDL cholesterol (HDL-C). Dietary factors (such as fatty acid intake) have been found to affect levels of HDL-C and influence risk of CVD. However, little is known about the associations of dietary fatty acid with serum HDL-P levels. Hypothesis: We hypothesized that dietary fatty acid associations with HDL-P are independent of HDL-C in men. Methods: Data were from 463 male participants in the 1996-98 cross-sectional INTERLIPID Study, ages 40-59 years, randomly selected from five populations; four in Japan (n=386) and one in Hawaii (n=77). Fatty acid intake was estimated from the mean of four in-depth 24-hour dietary recalls (% kcal per day). Individuals were excluded due to missing data on HDL-P or HDL-C and use of lipid lowering medication. Serum HDL-P was measured using nuclear magnetic resonance and HDL-C was measured using standard methods. Multiple linear regression models were used to assess the association between dietary fatty acid and each of the lipid measures. Results: In men, HDL-P and HDL-C were moderately correlated (r = 0.52, p<0.001). In Model 1 (Table), adjusted for age, country, alcohol intake, BMI, diabetes, hypertension, smoking status, and physical activity, most dietary fatty acids were significantly (p<0.05) associated with HDL-P and HDL-C levels. In Model 2, further adjusted for HDL-C, almost all fatty acids maintained a significant association with HDL-P. In contrast, most associations of fatty acids and HDL-C ceased to be significant after adjustment for HDL-P. Total SFA and omega-3 PUFA remained associated with HDL-C. Conclusion: HDL-P was significantly associated with fatty acid intake, independent of HDL-C. Associations of dietary fatty acid intake and HDL-C level were weaker and generally not independent of HDL-P in men. [ABSTRACT FROM AUTHOR]

Background: Obesity is an established risk factor for hypertension and end stage kidney disease. There is little information on how obesity relates to risk of impaired renal function in apparently healthy individuals. We investigated associations of body mass index (BMI) with timed 24-hour creatinine clearance (Ccr) and glomerular filtration rate (GFR) in the cross-sectional population-based INTERLIPID Study, ancillary study of the International Study on Macro- and Micro-Nutrients and Blood Pressure (INTERMAP). Methods: INTERLIPID participants ages 40-59 y from 5 INTERMAP research samples (4 Japanese and 1 Hawaiian) were investigated. Participants were ethnically all Japanese. Two timed 24-hour urine specimens were collected by each participant and analyses were performed in a central laboratory. Values of serum creatinine (Scr) were assayed by Jaffe's method in a Japanese central laboratory. Data were analyzed from 1,338 Japanese, 570 men and 563 women in Japan, 100 men and 105 women in Hawaii. Measures of kidney function were 24-hour Ccr (ml/min) and GFR (ml/min/1.73m). Ccr was calculated by equation (urine creatinine urine volume)/(Scr 1440); GFR was calculated as Ccr (1.73/body surface area (BSA)). BSA was estimated by the DuBois formula. In addition, estimated GFR (eGFR) was calculated by use of the Modification of Diet in Renal Disease (MDRD) Study equation, 186 Scr-1.154 age-0.203 0.742 (if female). All statistical analyses were stratified by gender. Adjusted mean values of Ccr, GFR, and eGFR in quartiles of BMI were estimated using analysis of covariance. Model 1 was adjusted for age; model 2, for age and urine volume; model 3 for variables in model 2 plus blood pressure, pulse rate, physical activity, smoking habit, alcohol consumption, urinary sodium excretion, HbA1c, and total serum cholesterol. Results: Ccr (mean (SD)) were 107.5 (18.9) in men in Japan, 91.9 (17.0) in women in Japan, 123.4 (25.1) in men in Hawaii, and 98.5 (20.3) in women in Hawaii. BMI quartile ranges were in men Q1 16.8-22.3, Q2 22.3-24.1, Q3 24.1-26.1, and Q4 26.1-42.9; in women Q1 15.9-21.2, Q2 21.2-23.0, Q3 23.0-25.1, and Q4 25.1-47.0. In men, BMI was positively related to multivariate-adjusted Ccr and GFR (P for trend across BMI quartiles <0.001 and <0.001, respectively), however, multivariate-adjusted eGFR was inversely associated with BMI (P for trend 0.001). In women, BMI was positively related to multivariate-adjusted Ccr (P for trend across BMI quartiles <0.001); multivariate-adjusted GFR and eGFR were not significantly associated with BMI. Interactions between age and BMI were not significant in men or women. Conclusions: These results indicate that excess BMI may lead to higher Ccr, and that the MDRD equation may underestimate GFR in middle-aged overweight or obese Japanese men. [ABSTRACT FROM AUTHOR]