February 2011
Testosterone treatment in elderly men with subnormal testosterone levels improves body composition and BMD in the hip. J Svartberg, I Agledahl, Y Figenschau, T Sildnes, K Waterloo and R Jorde. International Journal of Impotence Research. 2008:20;378–387
Researchers examined whether lower than normal T levels in elderly men were associated with a reduced quality of life (QoL), as well as physical and mental health, and whether T treatment could improve these conditions.
Unlike earlier testosterone treatment studies that recruited by advertising or direct mailing, researchers contacted elderly men (aged 60–80 years old) surveyed as part of the fifth (2001) Tromsø survey that measured T in 3,447 men. Sixty-nine elderly men with low T (defined as ≤11.0 nmol/l) and 104 men with normal T (>11.0 nmol/l) (control group) took part in a nested case-control study. Of the 69 men with low T, 31were excluded from participation in the one year intervention study due mainly to PSA levels above the reference range (>4.0µg/l) (no.18) or the use of warfarin (no.6). As a result 19 men were included in each of the T and placebo treatment groups (randomized in a double-blind fashion) – one man later withdrew from each group and one man from the T group died from cardiac arrhythmia not considered to be related to T therapy. Treatment was by an intramuscular injection of testosterone undecanoate 1000mg (Nebido®) or an identical looking placebo administered by a nurse (ensuring 100 percent compliance) at baseline and again at six, 16, 28, and 40 weeks. After 52 weeks the initial examinations and tests were repeated.
KEY POINTS
The nested case-control study showed:
The intervention study showed that:
Testosterone levels decrease with age2, 3, 4, 5 but this is characterised by high inter-individual variability.3
Some age-related changes in muscle and fat mass, bone mineral density (BMD) and sexual and cognitive functions resemble those observed in young testosterone deficient men. Such parallels suggest that T treatment in partially androgen-deficient older men may prevent or reverse these changes. However, placebo-controlled trials in older men with low or subnormal testosterone levels have so far yielded inconsistent results.6
In earlier studies T has been associated with a greater improvement in grip compared with placebo, although no earlier study has reported T making a difference to lower extremity muscle strength.7, 8, 9, 10
The main findings were that older men with low T had an unfavorable metabolic profile and that T treatment mainly improved body composition (reducing FM, SAT, TAT and increasing FFM) without affecting body weight. T treatment had no effect on the glucose metabolism or the lipids.
Men receiving T treatment did have significantly better grip than the placebo group at the end of the study as grip strength in the placebo group reduced - T maintained muscle strength in this limb.
This study is in line with other studies that have not shown an increase in strength in knee extension following T.
BMD in the hip increased significantly during T and there was a significant difference between the groups at the end of the treatment.