Effects of Protein Supplementation Combined with Exercise Training on Muscle Mass and Function in Older Adults with Lower-Extremity Osteoarthritis: A Systematic Review and Meta-Analysis of Randomized Trials

• Main Authors: Chun-De Liao, Yen-Tzu Wu, Jau-Yih Tsauo, Pey-Rong Chen, Yu-Kang Tu, Hung-Chou Chen, Tsan-Hon Liou
• Format: Article
• Language: English
• Published: MDPI AG 2020-08-01
• Series: Nutrients
• Subjects: osteoarthritis; sarcopenia; arthroplasty; protein supplement; exercise training; muscle mass
• Online Access: https://www.mdpi.com/2072-6643/12/8/2422

Aging and osteoarthritis (OA) are associated with a high risk of muscle mass loss, which can lead to physical disability. This study investigated the effectiveness of protein supplementation combined with exercise training (PS + ET) in improving muscle mass and functional outcomes in older adults with lower-limb OA. A comprehensive search of online databases was performed to identify randomized controlled trials (RCTs) on the effectiveness of PS + ET in older adults with hip or knee OA. Meta-analysis and risk of bias assessment of the included RCTs were conducted. Six RCTs were included in this systemic review; they had a median (range/total) Physiotherapy Evidence Database (PEDro) score of 7 (6–9) out of 10, respectively. Five RCTs that enrolled patients who underwent total joint replacement were included in this meta-analysis. The PS + ET group exhibited significant improvements in muscle mass (standard mean difference [SMD] = 1.13, <i>p</i> < 0.00001), pain (SMD = 1.36, <i>p</i> < 0.00001), and muscle strength (SMD = 0.44, <i>p</i> = 0.04). Our findings suggest that PS + ET improves muscle mass, muscle strength, and functional outcomes and reduces pain in older adults with lower-limb OA, particularly in those who have undergone total joint replacement.