Objective: In ageing men, the incidence and clinical significance of testosterone (T) decline accompanied by elevated luteinizing hormone (LH) are unclear. We describe the natural history, risk factors and clinical features associated with the development of biochemical primary hypogonadism (PHG, T < 10·5 nmol/l and LH>9·4U/l) in ageing men.
Design, patients and measurements: A prospective observational cohort survey of 3,369 community-dwelling men aged 40-79 years, followed up for 4·3 years. Men were classified as incident (i) PHG (eugonadal [EUG, T ≥ 10·5 nmol/l] at baseline, PHG at follow-up), persistent (p) PHG (PHG at baseline and follow-up), pEUG (EUG at baseline and follow-up) and reversed (r) PHG (PHG at baseline, EUG at follow-up). Predictors and changes in clinical features associated with the development of PHG were analysed by regression models.
Results: Of 1,991 men comprising the analytical sample, 97·5% had pEUG, 1·1% iPHG, 1·1% pPHG and 0·3% rPHG. The incidence of PHG was 0·2%/year. Higher age (>70 years) [OR 12·48 (1·27-122·13), P = 0·030] and chronic illnesses [OR 4·24 (1·08-16·56); P = 0·038] predicted iPHG. Upon transition from EUG to PHG, erectile function, physical vigour and haemoglobin worsened significantly. Men with pPHG had decreased morning erections, sexual thoughts and haemoglobin with increased insulin resistance.
Conclusions: Primary testicular failure in men is uncommon and predicted by old age and chronic illness. Some clinical features attributable to androgen deficiency, but not others, accompanied the T decline in men who developed biochemical PHG. Whether androgen replacement can improve sexual and/or physical function in elderly men with PHG merits further study.
© 2016 John Wiley & Sons Ltd.