Umbrella review of nonpharmacological interventions for intrinsic capacity in older adults

This study aims to synthesize existing evidence on the effectiveness of nonpharmacological interventions designed to increase the intrinsic capacity (IC) of community-dwelling older adults.

An umbrella review of systematic reviews from 2015 to October 31, 2024, with no language restrictions, was conducted. The review included five databases, including Embase, Ovid MEDLINE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Cochrane Central Register of Controlled Trials (CENTRAL), and the Joanna Briggs Institute (JBI) Library. Studies followed the preferred reporting items for overviews of reviews (PRIOR) statement. Eligible studies were systematic review and meta-analysis (SRMAs) that included any type of research aimed at enhancing IC in community-dwelling older adults (aged ≥60 years). The interventions covered seven domains: locomotion, vitality, cognitive function, psychological health, sensory function, sleep, and continence. Risk of bias and study quality were extracted via the AMSTAR tool, and GRADE approach was applied to assess the certainty of evidence.

Out of 6407 initially identified articles, 29 SRMAs comprising 400 studies with a total sample size of 43,849 participants were included. Mobility-focused interventions were the most studied among the seven domains of IC. Moderate to low-quality evidence supports the effectiveness of intrinsic foot muscle strengthening and gait/muscle training for improving locomotor functions in older adults with frailty or acute functional decline. Nonpharmacological interventions targeting cognitive and psychological functions ranked second in the volume of available evidence. No effective sensory or continence interventions were identified. Overall, interventions have demonstrated varying effectiveness, with impacts ranging from moderate to very low across the domains of IC.

This umbrella review provides a comprehensive assessment of nonpharmacological interventions for enhancing IC in older adults, highlighting the effectiveness of mobility/muscle strength training for improving locomotor function among frail older adult or those experiencing functional decline. However, the evidence for interventions targeting other IC domains remains limited, particularly for sensory function, and continence management. Future research should prioritize high-quality trials evaluating interventions in these areas to develop evidence-based guidelines for improving overall IC and promoting healthy aging in older adults.