Low Total Testosterone Levels are Associated With the Metabolic Syndrome in Elderly Men: The Role of Body Weight, Lipids, Insulin Resistance, and Inflammation; The Ikaria Study

Abstract

■ Abstract BACKGROUND:The prevalence of the metabolic syndrome (MetS) increases with age. Among other changes, testosterone levels decline with age. The relationship between testosterone levels and MetS components in older subjects has not been clearly defined until today. OBJEC-TIVES: The aim of this work was to evaluate the relationship between total serum testosterone levels and MetS and its components. METHODS: The working sample consisted of 467 elderly individuals (mean age 75 ± 6 years old, n = 220 men) from Ikaria Island, Greece. MetS was defined according to the NCEP ATPIII criteria. RESULTS: MetS prevalence was 52% in men and 64% in women. Those with MetS had lower testosterone levels; a 10 ng/dl increase in testosterone was associated with a 3% reduction in odds of having MetS in men (95% CI: 0.95-0.99), but not in women. This remained the result after various adjustments had been made, including daily hours of sleep. Testosterone was inversely associated with abnormal waist circumference, highsensitivity C-reactive protein (hs-CRP), insulin, and HDL cholesterol levels in men only. When lipid categories, hs-CRP, BMI, and insulin resistance levels were taken into account, testosterone lost its significance in predicting MetS (p > 0.20), suggesting that these markers possess a mediating effect. CONCLUSIONS: In elderly men, low serum testosterone was associated with MetS. Lipids, BMI, inflammation, and insulin resistance levels seem to explain this relationship, suggesting a potential mediating effect. This finding may support a research hypothesis relating serum testosterone to cardiovascular disease, which requires further research.

Testosterone a key factor in gender related metabolic syndrome

“…Testosterone regulates glucose tolerance and insulin resistance independently from MetS with sex differences because higher testosterone level has a protective effect in men while representing a high risk of type‐2diabetes in women . Low testosterone level correlated with reduced glucose tolerance and insulin activity, particularly in elderly men and is always correlated with type‐2 diabetes. Androgen deprivation, as observed in patients with prostate cancer, favourites the development of type‐2 diabetes because of diminished pancreatic β‐cell function .…”

Determinants of All-Cause Mortality and Incidence of Cardiovascular Disease (2009 to 2013) in Older Adults

“…9 Further details about the methods used in the baseline evaluation of the Ikaria Study may be found elsewhere. 10 …”

Prevalence, Pathophysiology, and Management of Androgen Deficiency in Men with Metabolic Syndrome, Type 2 Diabetes Mellitus, or Both

“…In men, the most widely reported relationship between MetS, T2DM, and testosterone deficiency is a link between low testosterone levels, obesity, and insulin resistance . What is not clearly known, however, is the mechanism or causality .…”

“…16 In men, the most widely reported relationship between MetS, T2DM, and testosterone deficiency is a link between low testosterone levels, obesity, and insulin resistance. 2,3,9,15,[17][18][19] What is not clearly known, however, is the mechanism or causality. 20 Studies have demonstrated that testosterone levels fall with age regardless of obesity, and SHBG levels increase with age, yielding less bioavailable testosterone.…”