Sarcopenia and health-related outcomes: an umbrella review of observational studies.
Level 1 - systematic review of randomized trials
Umbrella review synthesizing systematic reviews and meta-analyses (design analogy)
PubMed 34652767 · doi:10.1007/s41999-019-00233-w
What was done
The authors performed an umbrella review of systematic reviews and meta-analyses published up to February 20, 2019, examining associations between sarcopenia and various health-related outcomes. For each identified association, they evaluated random-effects summary effect sizes, 95% confidence intervals, heterogeneity (I2), small-study effects, excess significance bias, and 95% prediction intervals, categorizing the credibility of significant associations from class I (convincing) to class IV (weak).
What was found
Across 358 screened abstracts, 6 meta-analyses covering 14 distinct associations were included. Sarcopenia was associated with higher risk in 11 of 14 outcomes. Zero outcomes met criteria for class I (convincing) evidence. Three outcomes demonstrated class II (highly suggestive) evidence among older adults: increased risk of death in community-dwelling populations (OR = 3.60, 95% CI 2.96 to 4.37; n = 14,305), disability (OR = 3.04, 95% CI 1.80 to 5.12; n = 8,569), and falls (OR = 1.60, 95% CI 1.31 to 1.97; n = 12,261). All other investigated associations were supported only by weak evidence.
Why it matters
This review critically grades the epidemiological literature, demonstrating that while sarcopenia is frequently cited as a risk factor for multiple comorbidities, strong observational evidence exists primarily for mortality, disability, and falls rather than a broad spectrum of medical conditions.
Limits
Findings are derived entirely from observational studies, which cannot establish causality. No associations achieved the highest tier (class I) of evidence credibility. The abstract does not detail the definitions or diagnostic criteria used for sarcopenia across included meta-analyses, nor does it report the specific outcomes that showed weak or non-significant associations.
Cited by
- supports Sarcopenia is associated with a two- to threefold increased risk of falls, frailty, and disability in older adults.