Neuromuscular Electrical Stimulation Preserves Leg Lean Mass in Geriatric Patients.

AIM: This study aimed to examine changes in lean mass during hospitalization in geriatric patients and the effect of muscle activation by neuromuscular electrical stimulation. METHODS: Thirteen patients (69-94 yr) at a geriatric ward completed tests at hospital admission (days 2-3) and discharge (days 8-10). One leg received daily stimulation of the knee extensors, whereas the other leg served as a control leg. Lean mass was evaluated by dual-energy x-ray absorptiometry scans and muscle thickness by ultrasound scans. Muscle biopsies were collected from both legs at admission and discharge in nine patients and analyzed for fiber size, satellite cell number, and activation and expression of genes associated with muscle protein synthesis and breakdown, connective tissue, and cellular stress. RESULTS: The relative decline in leg lean mass and midthigh region lean mass was larger in the control (-2.8% ± 1.5%) versus the stimulated leg (-0.5% ± 1.4%, P < 0.05). Although there were no changes in fiber size or satellite cell number, the mRNA data revealed that, compared with control, the stimulation resulted in a downregulation of myostatin (P < 0.05) and a similar trend for MAFbx (P = 0.099), together with an upregulation of Collagen I (P < 0.001), TenascinC (P < 0.001), CD68 (P < 0.01), and Ki67 (P < 0.05) mRNA. CONCLUSION: These findings demonstrate a moderate decline in leg lean mass during a hospital stay in geriatric patients, whereas leg lean mass was preserved with daily neuromuscular electrical muscle activation. At the cellular level, the stimulation had a clear influence on suppression of atrophy signaling pathways in parallel with a stimulation of connective tissue and cellular remodeling processes.

Improved Functional Performance in Geriatric Patients During Hospital Stay.

OBJECTIVE: The aim of this work was to evaluate the time course of changes in strength and functional performance in elderly hospitalized medical patients. DESIGN: This was a prospective observational study in elderly medical patients of age 65 years or older at a geriatric department.Measurements were obtained on days 2 to 4, day 5 to 8, and days 9 to 13. Functional performance was measured with De Morton Mobility Index (DEMMI) test and a 30-second chair stand test (30-s CST). Muscular strength was measured with handgrip strength. Activity level was determined with accelerometry (ActivPAL). RESULTS: Results in DEMMI and 30-s CST gradually improved (P < 0.05), whereas handgrip strength remained unchanged (P > 0.05). Larger functional improvements were observed in patients with "high" compared to "low" and "moderate" activity level (P < 0.05). Changes in DEMMI score correlated with changes in 30-s CST (P < 0.05); however, changes in DEMMI score and 30-s CST were more likely to occur in patients with a low versus high functional level, respectively. CONCLUSIONS: Functional performance of the lower extremities in geriatric patients improves moderately over the time of a hospital stay of less than 14 days, with larger improvements in patients with high activity level. The DEMMI test and the 30-s CST seem to be complementary to each other when evaluating functional changes in a geriatric hospital population. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME CME OBJECTIVES: Upon completion of this article, the reader should be able to (1) describe changes in mobility and muscle strength of geriatric patients during a hospital stay of less than 14 days, (2) understand the significance of physical activity during hospital admission in geriatric patients, and (3) discuss the potential limitations of measures for assessing mobility and lower extremity strength status and change during a hospital admission. LEVEL: Advanced ACCREDITATION: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this activity for a maximum of 1.5 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.