Hand grip strength before and after SARS-CoV-2 infection in community-dwelling older adults

To assess the association between SARS-CoV-2 infection and decreased hand grip strength (HGS).

Longitudinal population-based study.

Community-dwelling older adults (aged ≥60 years) living in a rural Ecuadorian village struck by the SARS-CoV-2 pandemic.

Of 282 enrolled individuals, 254 (90%) finished the study.

HGS was measured 3 months before (January 2020) and 9 months after the introduction of the virus into the population (January 2021). SARS-CoV-2 antibody testing was performed in two rounds: in May-June (early) and September-November (late), 2020. An independent association between SARS-CoV-2 infection and HGS decline was assessed by fitting linear mixed models for longitudinal data. Changes in HGS scores in SARS-CoV-2 seropositive subjects, according to the time elapsed since seroconversion, were compared with those who remained seronegative.

Overall, 149 (59%) individuals became seropositive for SARS-CoV-2. The mean HGS (in kg) was 25.3 ± 8.3 at baseline and 23.7 ± 8.1 at follow-up (p = 0.028), with 140 individuals having >5% HGS decline between both measurements. The follow-up HGS measurement decreased by 1.72 kg in seropositive individuals, and by 0.57 kg in their seronegative counterparts (p < 0.001). SARS-CoV-2 seropositive individuals were 2.27 times more likely (95% CI: 1.33-3.87) to have a lower HGS measurement at the time of follow-up than those who remained seronegative. When compared with seronegative subjects, seropositive patients with early seroconversion were 3.41 times (95% CI: 1.73-6.74) more likely to have >5% HGS decline at the time of the follow-up than those with later, i.e., more recent, infections.

This study shows an independent deleterious impact of SARS-CoV-2 on HGS that is more marked among individuals with infections that occurred more than 8 months before follow-up HGS. Results suggest the possibility of chronic damage to skeletal muscles by SARS-CoV-2.