Follow-up study of the benefits of hormone replacement therapy on isometric muscle strength of adductor pollicis in postmenopausal women.

We have previously shown in a randomized open trial of Prempak C 0.6254 versus no treatment that adductor pollicis (AP) muscle strength increased in the treated group over 39–52 weeks [1]. Those who were weakest at the start of the trial benefited most, and the benefit occurred in the absence of any commensurate change in muscle size [1]. We have now tested whether this increased strength relative to the control group is maintained by re-measuring a representative sample of the subjects 2–4 years after they had originally taken part in the trial. Of the 87 subjects who completed the original trial, 72 agreed to take part. These subjects gave written informed consent for the follow-up study, which had been approved by the UCL}UCLH ethical committee. Five of these 72 were excluded on the basis of the original criteria, which they had developed since the end of the trial, 12 more of the original control group were excluded because they had taken hormone replacement therapy (HRT) for variable periods of time since the completion of the trial. Of the remaining 55 subjects, 25 women had previously been randomized to be controls and 30 to take HRT. Of these 30, 11 subjects had continued HRT treatment until follow-up. The 55 subjects used in the follow-up study were representative of the whole group who had completed the original trial in terms of age (60.430.4 years versus 60.830.3 years ; means3S.E.M.) and original AP muscle strength (59.531.2 N versus 58.530.8 N). The new observations were made over a period of 5 months, and consisted of measuring maximum voluntary force (MVF) and cross-sectional area (CSA) of AP as previously described [2,3], but using, for the force measurements, new equipment with minor mechanical design changes. The follow-up observations were also made by a different observer. The results show a larger