Prevalence of intrinsic capacity decline among community-dwelling older adults: a systematic review and meta-analysis

Abstract Background The concept of intrinsic capacity (IC) was introduced to define healthy aging and active aging based on functional capacity, yet there is limited understanding of the risk of IC decline at a population level. Aims To consolidate existing evidence for rates of IC decline and risk factors among community-dwelling adults 60 years or older. Methods According to the PRISMA guidelines, the literature search was independently conducted by two researchers in 8 databases from inception to January 2024 without language restrictions using combinations of free words and subject words. Qualities of included studies were assessed using Joanna Briggs Institute’s (JBI’s) critical appraisal checklist for prevalence studies. To pool the data, a random-effect meta-analysis was performed, followed by subgroup analysis and sensitivity analysis. All analyses were performed by Stata14.0. Results From 1594 records, 15 studies were extracted with 33,070 participants for meta-analysis. The pooled prevalence of IC decline in community settings was 67.8% (95% CI: 57.0-78.5%; P < 0.001). The prevalence of IC decline in China (66.0%; 95% CI: 53.2-78.9%) was found to be slightly lower than in other countries/regions (73.0%; 95% CI: 59.8-86.3%); however, this difference was not statistically significant. Other subgroup analyses revealed no statistically significant differences in prevalence. Age, hypertension, diabetes, gender, education level, living status, smoking, regular exercise, marital status, and osteoarthritis are associated with IC decline. Conclusion More than two-thirds of older adults in the community are affected by IC decline, and age, hypertension, diabetes, female sex, low education level, living alone, smoking, irregular exercise, unmarried, and osteoarthritis are all risk factors for IC decline.