Aims: Leptin has been shown to predict risk of metabolic syndrome (MetS), but it is not known whether this association is independent of body composition. Thus, we examined whether plasma leptin concentration predicted risk of MetS after adjustment for body composition measured using imaging.
Methods: We used the modified ATP III MetS criteria for an Asian population to classify participants in the longitudinal Japanese-American Community Diabetes Study as to presence of MetS. Participants without MetS at baseline (n=283) were followed for its development over 5 years. CT-measured adipose depots included baseline and 5-year intra-abdominal and abdominal subcutaneous fat areas at the level of the umbilicus, subcutaneous mid-thigh fat area, and subcutaneous thorax fat area at the nipple level. Other measurements included fasting plasma leptin and serum HDL-cholesterol and triglyceride concentrations, fasting and 2 hour glucose from a 75 g OGTT, systolic blood pressure (SBP), and medication use. Logistic regression analysis was used to estimate the odds of incident MetS by leptin concentration, body composition, and baseline MetS features.
Results: 65 participants developed MetS at 5-year follow-up. Multivariable logistic regression models showed a lower odds of incident MetS with 1-SD greater leptin concentration (OR = 0.45; 95% CI = 0.25-0.79; p = 0.006) adjusting for age, sex, CT-fat areas at baseline, and 5-year change in CT-fat areas. Additional adjustment for other MetS features at baseline (fasting and 2 hour glucose, triglycerides, HDL-cholesterol, SBP) yielded similar results (OR = 0.38; 95% CI = 0.20-0.71; p = 0.002).
Conclusions: Leptin concentration predicts MetS risk in Japanese Americans independent of body composition. Further research is needed to confirm this association in other populations and to understand potential underlying biologic mechanisms.
C. Liao: None. W.Y. Fujimoto: None. S.E. Kahn: Advisory Panel; Self; Boehringer Ingelheim GmbH, Elcelyx Therapeutics, Inc., Eli Lilly and Company, Intarcia Therapeutics, Inc., Janssen Research & Development, Merck & Co., Inc., Novo Nordisk A/S. D.L. Leonetti: None. E.J. Boyko: None.