Association of specific symptoms and metabolic risks with serum testosterone in older men.
Level 4 - case-series / case-control
Cross-sectional clinical cohort study
PubMed 16926258 · doi:10.1210/jc.2006-0401
What was done
A cross-sectional study evaluated 434 consecutive male outpatients aged 50–86 years attending an andrological outpatient clinic. Researchers tested whether psychosomatic complaints and metabolic risk factors related to serum testosterone concentrations in a symptom-specific manner and performed cluster analysis to identify patient subcohorts.
What was found
No single threshold for late-onset hypogonadism was found. Instead, symptoms accumulated at varying androgen levels: - Loss of libido or vigor increased below testosterone levels of 15 nmol/L (P < 0.001). - Depression and type 2 diabetes mellitus (also in nonobese men) were significantly more frequent below 10 nmol/L (P < 0.001). - Erectile dysfunction was associated with metabolic risks, smoking, and depressivity, with testosterone concentrations below 8 nmol/L contributing to the symptom (P = 0.003). - Cluster analysis identified three independent groups presenting with psychosomatic complaints, metabolic disorders, and sexual health problems, differing by androgen levels, age, and body mass index.
Why it matters
The findings indicate that late-onset hypogonadism does not conform to a single testosterone cutoff; instead, different clinical and metabolic symptoms emerge at distinct androgen thresholds.
Limits
The design is cross-sectional, precluding causal inferences. The sample consists of self-selected patients from a single andrology outpatient clinic rather than a representative population-based cohort, and quantitative effect sizes and confidence intervals were not reported in the abstract.
Cited by
- context Specific symptoms of testosterone deficiency emerge at distinct population thresholds: bone loss around 300 ng/dL, decreased frequency of sexual thoughts at 215 ng/dL, and loss of vigor around 290 ng/dL.