Prevalence of Traditional East Asian Medicine Patterns among Older Adults with Frailty: a systematic review of observational studies

Frailty is a common geriatric syndrome that increases vulnerability to adverse health outcomes.Traditional East Asian medicine (TEAM) provides a distinct framework for understanding frailty through syndrome differentiation; however, the prevalence and distribution of TEAM patterns in frail populations remain unclear.This review aimed to systematically evaluate and meta-analyze the prevalence of TEAM patterns in frail older adults.A comprehensive search of five electronic databases was conducted through May 2025.Observational studies reporting TEAM patterns in adults aged 60 years with validated frailty diagnoses were included.Two independent reviewers screened studies, extracted data, and assessed methodological quality using the Newcastle-Ottawa Scale.Random-effects meta-analysis was used to pool prevalence estimates.Eleven observational studies involving 3,345 participants met the inclusion criteria.All studies were conducted in China; no eligible studies from Korea or Japan were identified.Methodological quality was generally low, and no study was rated as high quality.Deficiency-related TEAM patterns predominated.The most frequently reported patterns were qi-blood deficiency (exploratory pooled prevalence: 24.0%) and kidney essence deficiency (24.0%), followed by spleen deficiency with phlegm-dampness (23.0%).Liver-kidney yin deficiency had a pooled prevalence of 26.0%, based on two studies.Substantial heterogeneity was observed across studies (I 2 > 80%), and overall methodological limitations reduce the precision and generalizability of these findings.Syndrome differentiation was conducted by TEAM practitioners using the four diagnostic methods, consistently incorporating tongue and pulse examination; however, diagnostic criteria varied among studies.Age, comorbidities, and nutritional markers were associated with frailty.Exploratory analysis suggests frail older adults predominantly exhibit deficiency-related patterns, particularly qi-blood deficiency, kidney essence deficiency, and spleen deficiency with phlegm-dampness.However, the low methodological quality, substantial heterogeneity, and restriction to Chinese populations indicate that these findings should be considered preliminary and require confirmation through rigorously designed studies.