Leptin and dementia over 32 years-The Prospective Population Study of Women

BackgroundWe have shown that high mid-life central adiposity may increase the risk for dementia after 32 years. Leptin, an adipose tissue hormone, is correlated with adiposity measures and may contribute to a better etiological understanding of the relationship between high adiposity and dementia. We explored the relationship between serum leptin in mid-life and dementia, which is a late-life outcome.MethodsA longitudinal cohort study, the Prospective Population Study of Women, in Gothenburg, Sweden, includes a representative sample of 1462 women followed from mid-life ages of 38 to 60 years to late-life ages of 70 to 92 years. Women were examined in 1968, 1974, 1980, 1992, and 2000 using neuropsychiatric, anthropometric, clinical, and other measurements. Serum leptin was measured on samples collected at the 1968 baseline examination, after storage at −20°C for 29 years. Cox proportional hazards regression models estimated incident dementia risk by baseline leptin. Logistic regression models related leptin levels to dementia among surviving participants 32 years later. All models were adjusted for multiple potential confounders.ResultsMid-life leptin was not related to dementia risk using Cox or logistic regression models. This was observed despite positive baseline correlations between leptin and adiposity measures, and given our previous report of high mid-life waist-to-hip ratio being related to a twofold higher dementia risk.ConclusionsLeptin is not a mid-life marker of late-life dementia risk in this population sample of Swedish women born between 1908 and 1930.