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In healthy older adults, 10 days of bed rest results in a substantial loss of lower extremity strength, power, and aerobic capacity, and a reduction in physical activity, but has no effect on physical performance. Identification of interventions to maintain muscle function during hospitalization or periods of bed rest in older adults should be a high priority.

Objective To assess the association of industry funding with the characteristics, outcome, and reported quality of randomized controlled trials (RCTs) of drug therapy for rheumatoid arthritis (RA). Methods MEDLINE and Cochrane Central Register of Controlled Trials databases were searched to identify original RA drug therapy RCTs published in 2002–3 & 2006–7. Two reviewers independently assessed each RCT for the funding source, characteristics, outcome [positive (statistically significant result favoring experimental drug for the primary outcome) or not positive], and reporting of methodological measures whose inadequate performance may bias treatment effect assessment. RCTs registered at ClinicalTrials.gov and completed in the study years were assessed for publication bias. Results 103 eligible RCTs were identified with following funding sources: 58 (56.3%) industry; 19 (18.4%) non-profit; 6 (5.8%) mixed; and 20 (19.4%) unspecified. Industry funded RCTs had significantly more study centers and subjects; while non-profit funded RCTs had longer duration, and were more likely to study different treatment strategies. Outcome could be assessed for 86 (83.5%) RCTs. Funding source was not associated with higher likelihood of positive outcomes favoring the sponsored experimental drug [industry (75.5%), non-profit (68.8%), mixed (40%), and unspecified (81.2%); p = 0.37]. Industry funded RCTs had trend towards higher likelihood of non-publication (38.6% versus 16.7%, p = 0.093). Industry-funded RCTs reported more frequent performance of double-blinding, adequate participant flow description, and intention-to-treat analysis. Conclusion Industry funding was not associated with higher likelihood of positive outcomes of published drug therapy RCTs for RA, and reported better on some key RCT quality measures.

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Moving from a supine to standing position (orthostasis) requires multiple cardiovascular and autonomic adjustments to maintain blood pressure and cerebral perfusion. We examined cardiovascular and catecholamine responses to a standardized orthostatic challenge before and after 10 d of bedrest in healthy men and women (n = 24) aged 55 – 80 y. The orthostatic test involved measurements of heart rate, blood pressure, and serum catecholamines during 10 min of supine rest followed by 10 min of standing. A test was terminated if the subject experienced any orthostatic symptoms (e.g. lightheadedness). Two subjects were symptomatic during pre‐bedrest testing, while 5 subjects were symptomatic post‐bedrest. Heart rate during the standing portion of the test was higher than the supine value; the difference between standing and supine values was significantly greater at post‐ vs. pre‐bedrest (22.3 ± 9.7 vs. 14.1 ± 15.8 bpm, respectively, p = 0.01). The difference between standing and supine serum norepinephrine values was also higher at post‐ vs. pre‐bedrest (282.6 ± 167.0 vs. 162.8 ± 271.0 pg/mL, p = 0.05). No significant differences in blood pressure or epinephrine concentration were observed. These data indicate that 10 d of bedrest can result in greater indices of orthostatic intolerance in previously asymptomatic healthy older adults. NIH P01AG023591, M01RR14288, and M01RR00073.

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Older individuals are more likely to experience extended hospitalization. Thus, there is an inherent risk of prolonged inactivity and the accompanying functional decline. We have previously demonstrated that the provision of an essential amino acid (EAA) supplement in younger individuals subjected to 28d of bed rest eliminates the loss of lean body mass (LBM) and ameliorates the loss in muscle function. We hypothesized that EAA administration in older individuals subjected to 10d bed rest would also spare LBM and muscle function. Twenty‐two older subjects were given a placebo (n = 12, 68 ± 5 (SD) yrs, 83 ± 19 kg) or 15g of EAA (n = 10, 71 ± 6, 72 ± 8 kg) 3 times per day throughout 10d of bed rest. Measures of LBM, muscle protein synthesis, and muscle strength and function were determined before and after bed rest. Outcomes were tested statistically by 2X2 ANOVA and Tukey's post‐hoc test. EAA supplementation maintained muscle protein synthetic rate (P=0.025), but did not ameliorate the loss of LBM. EAA supplementation resulted in a preservation of plantar flexion strength (p=0.054), stair ascent power (p=0.029), stair descent power (p=0.026), and floor transfer time (p=0.027). Despite the inability of EAA to preserve LBM, muscle function was maintained. EAA supplementation maintains muscle protein turnover and preserves muscle function in older, inactive individuals.Project funded by the National Institutes of Health grant PO1 AG023591 (Evans).

Prolonged inactivity in elderly individuals causes a loss of lean muscle mass and compromises strength and function, which may impair subsequent rehabilitation and the ability to perform daily activities. We examined the effects of essential amino acid supplementation (EAA) on isometric (ISO) and isokinetic concentric (CON) torque and stair ascent/descent power after 10 days of bed rest in older adults. Twenty women and men (placebo: n=12, 67 ± 5yrs and EAA: n=8, 67 ± 5yrs) participated. During bed rest, subjects consumed an EAA supplement (15g,3*/day) or placebo. Knee extensor ISO (45°) and CON (60 & 180°·s−1) peak torque were measured. Stair ascent and descent power were assessed over ten steps (body weight*9.8*distance/time). The placebo group experienced larger reductions in ISO and CON 60°·s−1 peak torque and stair ascent and descent power than the EAA group (−11.1 to −18.2%); while the EAA group demonstrated a larger decrease in CON 180°·s−1peak torque (−16.1±5.3%) than the placebo group. No difference was found between the placebo group and the EAA group for any of the outcome measures (p >0.112). In older adults, 10 days of strict bed rest decreased muscle strength and stair ascent/decent power. The EAA group exhibited smaller reductions; however, these reductions did not differ from the placebo group. AG 023591, MO1 RR 00073