Prevalence of Symptomatic Androgen Deficiency in Men
Introduction: It is accepted that androgen deficiency diagnosis in men should be made on biochemical and clinical criteria. However, the majority of prevalence estimates of androgen deficiency are made by using only low testosterone levels.
Therefore, this study was conducted to assess the association of androgen deficiency symptoms and low total testosterone and calculated free testosterone levels. It was also done to estimate the prevalence of symptomatic androgen deficiency in American men.
Methods: The study (which was population-based and observational) included 1,475 men; they were black, Hispanic, and white, and they were randomly selected from the Boston Area Community Health Survey. The men were ages 30-79 years (mean: 47.3 ± 12.5 years). They had complete data on testosterone, SHBG, and symptoms of androgen deficiency; the men were not using any medications that affect sex steroid levels.
Results: About 24% of the men had total testosterone < 300 ng/dL; this was defined as low total testosterone. In the calculated free testosterone, 11% met the low criteria—levels < 5 ng/dL.
Prevalence of symptoms associated with androgen deficiency were: osteoporosis/fracture (1%), low libido (12%), erectile dysfunction (16%), and 2 or more of the non-specific symptoms (20%—sleep disturbance, depressed mood, lethargy, diminished physical ability).
In men 50+, 47.6% had low total testosterone levels but were asymptomatic.
In regards to symptomatic androgen deficiency, the crude prevalence was 5.6% (95% confidence interval: 3.6%, 8.6%). While prevalence was low in men < 70 years (3.1%-7.0%), it increased markedly with age; the prevalence of symptomatic androgen deficiency was 18.4% in men > 70 years.
Conclusions: Prevalence of symptomatic androgen deficiency increases significantly with age; in men between 30 and 79 years, prevalence is 5.6 %, and it is higher in men >70 years. As the US population ages, there will be a large increase in the number of men with symptomatic androgen deficiency.
Most previous studies evaluating the prevalence of androgen deficiency in men only have looked at low testosterone levels, without correlating T levels with symptoms of androgen deficiency. Given that the diagnosis of hypogonadism should include both biochemical and clinical criteria, it is important that prevalence studies take both into account.
The Massachusetts Male Aging Study (MMAS), conducted in the 1980s and 1990s, indicated that the prevalence of symptomatic androgen deficiency was between 6-12%. In this population-based, observational study, total and calculated free testosterone levels were correlated with symptoms of androgen deficiency in order to estimate an overall prevalence of 5.6%. This number increases substantially with age with a prevalence of 18.4% in the age group 70-79. Prevalence does not appear to be significantly related to race or ethnic group. Future studies looking at the risks and benefits of treating androgen deficiency, particularly the elderly population, are warranted.