The Longitudinal Relationship of Sexual Function and Androgen Status in Older Men: The Concord Health and Ageing in Men Project

Context:

It is unclear whether declining sexual function in older men is a cause or consequence of reduced androgen status.

Objective:

Longitudinal associations were examined between reproductive hormones and sexual function in older men.

Design, Setting, and Participants:

Men aged 70 years and older from the Concord Health and Ageing in Men Project study were assessed at baseline (n = 1705) and 2-year follow-up (n = 1367), with a total of 1226 men included in the final analyses.

Main Outcomes and Measures:

At both visits, serum testosterone (T), dihydrotestosterone (DHT), estradiol (E2), and estrone (E1) were measured by liquid chromatography-tandem mass spectrometry, and SHBG, LH, and FSH were measured by immunoassay. Sexual functions (erectile function, sexual activity, and sexual desire) were self-reported via standardized questions.

Results:

In longitudinal analyses, although baseline hormones (T, DHT, E2, and E1) did not predict decline in sexual function, the decline in serum T (but not DHT, E2, or E1) over 2 years was strongly related to the change in sexual activity and desire (but not erectile function). For each 1-SD decrease in T from baseline to 2-year follow-up, there was a multivariate-adjusted odds ratio of 1.23 (95% confidence interval, 1.12–1.36) for an additional risk of further decline in sexual activity. However, the magnitude of the decrease in serum T was strikingly small (<10%). Similar associations were found for changes over 2 years in serum T and decline in sexual desire, but not for erectile function.

Conclusions:

We found a consistent association among older men followed over 2 years between the decline in sexual activity and desire, but not in erectile function, with a decrease in serum T. Although these observational findings cannot determine causality, the small magnitude of the decrease in serum T raises the hypothesis that reduced sexual function may reduce serum T rather than the reverse.