Association Between Hormones and Metabolic Syndrome in Older Italian Men

Abstract

OBJECTIVES: To determine whether low levels of testosterone, sex hormone binding globulin (SHBG), insulin‐like growth factor‐1 (IGF‐1), and dehydroepiandrosterone sulfate (DHEAS) and high levels of cortisol and leptin would be associated with metabolic syndrome (MS). DESIGN: Cross‐sectional. SETTING: Population‐based sample of older Italian men. PARTICIPANTS: Four hundred fifty‐two men aged 65 and older enrolled in the Invecchiare in Chianti (InCHIANTI) study. MEASUREMENTS: Complete data on testosterone, cortisol, DHEAS, SHBG, fasting insulin, IGF‐1 and leptin. MS was defined according to Adult Treatment Panel III criteria. RESULTS: MS was present in 73 men (15.8% of the sample). After adjusting for confounders, total testosterone (P<.05) and log (SHBG) (P<.001) were inversely associated, whereas log (leptin) was positively associated with MS (P<.001). Independent of age, log (SHBG) was positively associated with high‐density lipoprotein cholesterol (P<.05) and negatively associated with abdominal obesity (P<.001) and triglycerides (P<.001). Log (leptin) was significantly associated with each component of MS. Cortisol, DHEAS, free and bioavailable testosterone, and IGF‐1 were not associated with MS. Having three or more hormones in the lower (for hormones lower in MS) or the upper (for hormones higher in MS) quartile was associated with three times the risk of being affected by MS (odds ratio=2.8, 95% confidence interval=1.3–6.9) (P=.005), compared with not having this condition. CONCLUSION: Total testosterone and SHBG are negatively and leptin is positively associated with MS in older men. Whether specific patterns of hormonal dysregulation predict the development of MS should be tested in longitudinal studies.