Handgrip strength asymmetry is associated with the risk of neurodegenerative disorders among Chinese older adults.
Level 3 - non-randomized controlled study
Prospective longitudinal cohort study with competing risk analysis.
PubMed 35178892 · doi:10.1002/jcsm.12933
What was done
Data from 4,925 participants aged 60 and older from three waves (2011–2015) of the China Health and Retirement Longitudinal Study were analyzed. Handgrip strength (HGS) asymmetry was defined as a ratio of maximal non-dominant to dominant HGS of <0.9 or >1.1. Incident physician-diagnosed neurodegenerative disorders were identified via self-report or proxy report. Cause-specific hazard models and Fine-Gray subdistribution hazard models were used to assess the association between HGS asymmetry and incident neurodegenerative disorders, treating mortality as a competing risk over 4 years of follow-up.
What was found
Of 4,925 participants (mean age 68.1 years, 49.7% female), 45.2% (n = 2,227) had HGS asymmetry and 18.0% (n = 888) had low HGS at baseline. Over 4 years of follow-up, 156 cases of incident neurodegenerative disorders occurred (incidence rate: 8.7 per 1,000 person-years, 95% CI: 7.4–10.2) alongside 422 deaths (incidence rate: 23.5 per 1,000 person-years, 95% CI: 21.4–25.9). HGS asymmetry was associated with increased risk of incident neurodegenerative disorders in both cause-specific (HR = 1.66, 95% CI: 1.202–2.297, P = 0.002) and subdistribution hazard models (SHR = 1.65, 95% CI: 1.202–2.285, P = 0.002). Low HGS was associated with higher mortality (HR = 1.61, 95% CI: 1.297–1.995, P < 0.001; SHR = 1.58, 95% CI: 1.286–1.951, P < 0.001), whereas HGS asymmetry was not.
Why it matters
Measuring grip asymmetry alongside absolute grip strength offers a simple, non-invasive physical metric that may help identify older adults at elevated risk for developing neurodegenerative conditions.
Limits
Outcomes relied on self-reported or proxy-reported physician diagnoses rather than clinical neurological workups or biomarker validation. Specific neurodegenerative diagnoses (e.g., Alzheimer's versus Parkinson's disease) were not differentiated in the abstract. Follow-up was relatively short (4 years) for slow-progressing conditions, and the population was restricted to Chinese older adults.
Cited by
- supports Grip strength asymmetry is studied as an early predictive marker for neurological conditions such as Alzheimer's and Parkinson's disease, reflecting nerve denervation and neurological health.