Bioavailable testosterone in men with rheumatoid arthritis-high frequency of hypogonadism

OBJECTIVES: To study bioavailable testosterone (T) in men with rheumatoid arthritis (RA) by determining non-sex hormone-binding globulin (SHBG)-bound T (NST) under standardized conditions and to investigate if NST is related to disease variables. METHODS: Basal serum concentrations of total T, SHBG and luteinizing hormone (LH) were measured in 104 men with RA, and the levels of NST as well as the quotient T/SHBG were calculated. The data were compared with those of 99 age-matched healthy men. The results were analysed separately for the age groups 30-49, 50-59 and 60-69 yr. RESULTS: The RA men had lower NST levels than the healthy men in all age groups. T levels and the T/SHBG ratio were lower only in the age group 50-59 yr. SHBG did not differ significantly. LH was significantly lower in the patients than in the controls. Thirty-three of the 104 patients were considered to have hypogonadism compared with seven of the 99 healthy men. The only clinical variable apart from age that had a significant impact on NST was the Stanford Health Assessment Questionnaire (HAQ). CONCLUSION: Men with RA had lower levels of bioavailable T and a large proportion were considered hypogonadal. The low levels of LH suggested a central origin of the relative hypoandrogenicity.