Temporal Trends in the Handgrip Strength of 2,592,714 Adults from 14 Countries Between 1960 and 2017: A Systematic Analysis.

BACKGROUND: Handgrip strength (HGS) is an excellent marker of functional capability and health in adults, although little is known about temporal trends in adult HGS.

OBJECTIVES: The aim of this study was to systematically analyze national (country-level) temporal trends in adult HGS, and to examine the relationships between national trends in adult HGS and national trends in health-related and socioeconomic/demographic indicators.

METHODS: Data were obtained from a systematic search of studies reporting temporal trends in HGS for adults (aged ≥ 20 years) and by examining national fitness datasets. Trends in mean HGS were estimated at the country-sex-age group level by best-fitting sample-weighted linear/polynomial regression models, with national and sub-regional (pooled data across geographically similar countries) trends estimated by a post-stratified population-weighting procedure. Pearson's correlations quantified relationships between national trends in adult HGS and national trends in health-related and socioeconomic/demographic indicators.

RESULTS: Data from ten studies/datasets were extracted to estimate trends in mean HGS for 2,592,714 adults from 12 high- and 2 upper-middle-income countries (from Asia, Europe and North America) between 1960 and 2017. National trends were few, mixed and generally negligible pre-2000, whereas most countries (75% or 9/12) experienced negligible-to-small declines ranging from an effect size of 0.05 to 0.27, or 0.6 to 6.3%, per decade post-2000. Sex- and age-related temporal differences were negligible. National trends in adult HGS were not significantly related to national trends in health and socioeconomic/demographic indicators.

CONCLUSIONS: While trends in adult HGS are currently limited to 14 high- and upper-middle-income countries from three continents, adult HGS appears to have declined since 2000 (at least among most of the countries in this analysis), which is suggestive of corresponding declines in functional capability and health.

PROSPERO REGISTRATION NUMBER: CRD42013003678.