Integrating Evidence on Dynapenia and Dynapenic Obesity: An Umbrella Review of Health Outcomes Among Community-Dwelling Older Adults

<b>Background:</b> Dynapenia refers to the age-related decline in muscle strength that occurs even when muscle mass is preserved. It has become an important issue in older adults because reduced strength is strongly linked to many negative health outcomes. When dynapenia occurs together with obesity-referred to as dynapenic obesity or dynapenic abdominal obesity-the risks, including mortality, falls, and the development of multiple chronic conditions, appear to increase even further. This umbrella review aimed to bring together and summarize existing systematic reviews and meta-analyses that examined how dynapenia and its obesity-related subtypes are associated with mortality, falls, and multimorbidity among community-dwelling older adults. <b>Methods:</b> Following PRISMA 2020 and JBI guidelines, six major databases and search engines (PubMed, Embase, Cochrane Library, Scopus, CINAHL, and Airiti Library) were searched from their inception to October 2025. Systematic reviews and meta-analyses involving adults aged 60 years and older and reporting quantitative results on the relationships between dynapenia-related conditions and adverse health outcomes were included. The methodological quality of each review was evaluated using AMSTAR 2, and the certainty of evidence was assessed with the GRADE approach. This umbrella review followed the PRIOR framework and was reported according to PRISMA 2020. The protocol for this review was registered in PROSPERO (ID: CRD 42023415232). <b>Results:</b> A total of four systematic reviews and meta-analyses were included, covering more than 73,000 community-dwelling older adults. The pooled data showed that dynapenic obesity significantly increased the risk of all-cause mortality, with hazard ratios ranging from 1.50 (95% CI 1.14-1.96) to 1.73 (95% CI 1.38-2.16). Dynapenic abdominal obesity was also strongly linked to falls, with pooled estimates ranging from HR = 1.82 (95% CI 1.04-3.17) to RR = 6.91 (95% CI 5.42-8.80). For multimorbidity, older adults with dynapenia had 1.38 times higher odds of having two or more chronic diseases than those without dynapenia (OR = 1.38, 95% CI 1.10-1.72). Based on the GRADE evaluation, the certainty of evidence was moderate for mortality and falls and low for multimorbidity. <b>Conclusions:</b> Overall, the findings indicate that dynapenia and its obesity-related forms meaningfully increase the risks of mortality, falls, and multimorbidity among community-dwelling older adults. Importantly, these results position dynapenia not merely as a musculoskeletal condition, but as a clinically relevant marker of aging-related vulnerability. This underscores the need for early screening of muscle strength alongside obesity-related indicators, as well as the development of integrated preventive strategies that combine strength-oriented interventions with obesity management in older populations.