Effect of genotype on change in strength over 12 months of the LACE trial.
Proportionate strength was determined by dividing MVC at month 12 by MVC at baseline allowing us to combine data from men and women in the study. (A) Individuals with the DD genotype had a higher proportionate strength at month 12 than individuals with the II/ID genotype (Mann-Whitney U test). (B and C) Comparison of the baseline and 12-month MVC showed that the DD individuals (B) increased in strength over the course of the trial (p = 0.003 Wilcoxon-signed rank test) whereas there was no change in strength in the II/ID individuals (C). There was no effect of perindopril on proportionate strength in either the DD or II/ID genotypes (D).To determine if the increase in muscle strength was a consequence of the treatment with perindopril, we compared QMVC at 0 and 12 months in II/ID and DD individuals who completed the study. This analysis showed that, consistent with the overall trial data, perindopril did not cause the increase in strength in the DD genotype individuals or the II/ID individuals as specified groups. Wilcoxon matched-pairs analysis showed that the DD individuals on perindopril did not increase their strength over 12 months (change in QMVC = 2.55 kg (-0.35, 4.15) p = 0.196) but those not on perindopril did (change in QMVC = 1.8 kg (1.2, 6.6), p = 0.008). However, strength did not increase in II/ID individuals whether on perindopril (change in QMVC = 1.45 kg (-2.3, 3.9), p = 0.247), or not (change in QMVC = -0.4 kg (-2.6, 3.3), p = 0.860). In the absence of perindopril, the increase in proportionate strength was larger in individuals with the DD than the II/ID genotype but there was no difference in the presence of perindopril (