Maximum oxygen uptake corrected for skeletal muscle mass accurately predicts functional improvements following exercise training in chronic heart failure.

BACKGROUND: Skeletal muscle mass and peak oxygen uptake are important predictors of functional status and outcome in patients with stable chronic heart failure. AIMS: To assess changes in skeletal muscle mass and peak oxygen uptake following an exercise training program. METHODS: Thirty-six patients with moderate stable chronic heart failure were randomly allocated to either a bicycle ergometer (bike) or functional electrical muscle stimulators (FES) applied to quadriceps and gastrocnemius muscles to be used daily for six weeks. Dual-energy X-ray absorptionometry (DEXA) scanning was performed before and after training along with symptom limited cardiopulmonary exercise test, quadriceps strength and fatigue resistance, and 6-min walk test. RESULTS: Both exercise modalities resulted in improvements in treadmill exercise time, leg strength, 6-min walk test and peak oxygen uptake per kilogram of skeletal muscle. Despite significant improvements in functional capacity, there were no significant changes in body composition for total skeletal muscle mass, leg muscle mass or total body fat content. Skeletal muscle mass was strongly predictive of maximum oxygen uptake at baseline (r=0.61, p<0.001) and after exercise training (r=0.68, p<0.001). CONCLUSIONS: In moderate stable chronic heart failure, exercise training using bicycle ergometer or FES results in favourable qualitative rather than quantitative changes in skeletal muscle. Correction of maximum oxygen uptake for skeletal muscle mass rather than total body mass is a more sensitive measure of changes associated with exercise training.

Longitudinal changes in muscle strength and mass after acute stroke.

BACKGROUND: Reduced mobility after stroke may cause a loss of muscle mass which may, in theory, contribute to disability. We investigated longitudinal changes in muscle strength, lean cross-sectional area and muscle mass in all limbs after acute stroke. METHODS: We recruited 17 patients within 72 h of hospital admission and measured (a) hand grip strength, (b) knee extensor strength and (c) arm and leg lean cross-sectional area on 6 occasions over 6 months. Appendicular and total muscle mass (dual-energy X-ray absorptiometry) were measured at 3 weeks and 6 months. RESULTS: There was no significant change over time in the strength, lean cross-sectional area and muscle mass of the arms or legs. We noted that muscle strength was substantially lower in all limbs compared with population norms. CONCLUSION: We found no evidence of a decline in muscle strength or mass in any limb after the stroke, which could have been attributed to reduced mobility. The observed muscle weakness in the ipsilateral side may have pre-dated the stroke.

Association of low general health status, measured prospectively by Euroqol EQ5D, with osteoporosis, independent of a history of prior fracture.

OBJECTIVES: There have been no studies of generic health-related quality of life (HR-QOL) measured prospectively, in patients referred for bone mass measurement. The aim of this study was to examine the relationship between HR-QOL, measured before DXA scanning was undertaken, and bone mineral density (BMD). Comparison of HR-QOL with the age- and sex-matched general population was also made. DESIGN: HR-QOL questionnaires were completed by patients who were being entered into a randomized, prospective, parallel group trial to assess the impact of direct access DXA scanning (DADS) versus referral to a hospital consultant, upon clinical decision making by general practitioners (GPs) (Dhillon et al., Osteoporos Int 14:326-333, 2003). HR-QOL questionnaires were completed prior to both randomization and DXA scanning. PARTICIPANTS: 325 patients from 18 representative general practices of a total of 77 in the city of Edinburgh. Patients had been referred by their GPs who had access to national guidelines on the identification of patients at high risk of osteoporosis. OUTCOME MEASURES: Generic HR-QOL was measured using Euroqol (EQ5D). This provides a profile of self-reported problems in five dimensions (EQ5D(profile)), health utility (EQ5D(utility)), and a visual analogue global self-rated health assessment (EQ5D(vas)). RESULTS: Odds ratios (ORs) for any self-reported problems on EQ5D(profile) were higher in patients with osteoporosis than those without, and compared with the general population. Age-adjusted mean (SD) EQ5D(utility )was significantly lower in patients with osteoporosis than in those without (0.65 [0.28] vs 0.76 [0.27]; p< 0.01), but the difference lessened with advancing age. Age-adjusted mean (SD) EQ5D(vas) was significantly reduced in patients with compared with no osteoporosis (68 [20] vs 76 [16]; p<0.01). There were no such differences in patients with a history of prior fracture compared with those without a history of prior fracture. CONCLUSIONS: Female patients with osteoporosis have reduced generic HR-QOL compared with the age-matched female general population, irrespective of a history of prior fracture. The causal relationship between osteoporosis and HR-QOL, if any, is unclear. Further studies are needed to define this relationship and to determine whether treatment of osteoporosis has a beneficial effect on HR-QOL independent of fracture risk.