Abstract Body: Introduction
The American Heart Association (AHA) recently introduced the cardiovascular-kidney-metabolic (CKM) syndrome as a systemic disorder with connections among heart disease, kidney disease, diabetes, and obesity. The relationship between cardiovascular-kidney-metabolic (CKM) syndrome and reproductive hormones in older men is unclear.
Hypothesis
Testosterone and other major reproductive hormones in older men may be important biomarkers for CKM syndrome.
Methods
Men ages 70 years and older from the Concord Health and Ageing in Men Project study (n = 1399) were assessed at baseline. Testosterone and dihydrotestosterone (DHT) were measured by liquid chromatography-tandem mass spectrometry, and luteinizing hormone (LH) and follicle-stimulating hormone (FSH) by immunoassay. CKM syndrome was defined based on the Presidential Advisory from the AHA. Logistic regression model (odds ratio, OR) was used for analyses. The model building for all analyses included relevant covariates notably age, marital status, alcohol consumption, smoking, and physical activity.
Results
In this cross-sectional observational study of older men aged 76.8 ± 5.5 years, most participants had CKM stage 2 or higher. Approximately 46% in stage 2, 20% in stage 3, and 31% were in stage 4. In the multivariable-adjusted model, participants in the lowest testosterone quartile were more likely to have CKM stage 3 (OR:1.59, 95%CI:1.06-2.39) and stage 4 (OR: 1.59, 95%CI:1.14-2.21) when compared to those in the highest testosterone quartile. Similar observations were shown for DHT. In contrary, participants in the lowest LH quartile were less likely to have CKM stage 3 (OR:0.59, 95%CI:0.40-0.87) and stage 4 (OR:0.65, 95%CI:0.46-0.92) when compared to the highest LH quartile. Similar observations were shown for FSH. No significant associations were observed for the lower CKM stages across all the studied reproductive hormones.
Conclusions
Low testosterone and DHT, and high LH and FSH are associated with advanced stages of CKM syndrome in older men. Our follow-up longitudinal study will further explore whether observed associations between the reproductive hormones and CKM syndrome represents a causal relationship, or rather biomarkers of risk.