Grip strength is strongly and inversely associated with all-cause mortality and incidence of and mortality from cardiovascular disease, respiratory disease, chronic obstructive pulmonary disease (COPD), all cancer, and subtypes of cancer, with associations being modestly stronger in the younger age groups, according to a study published in the BMJ.
Carlos A Celis-Morales, a research associate from the Institute of Cardiovascular and Medical Sciences at the University of Glasgow in the UK, and colleagues investigated the associations of grip strength with all-cause mortality and disease-specific incidence and mortality and whether the addition of grip strength improves the prediction ability of established office-based risk scores.
Outcomes were incidence of and mortality from cardiovascular disease, all respiratory disease, COPD, all cancers, breast cancer, prostate cancer, colorectal cancer, and lung cancer, as well as all-cause mortality, with the exposure variable being grip strength (age- and sex-specific quarters and 5-kg increase in grip strength).
Of the 502,628 participants recruited to UK Biobank, 502,293 (99%) had data on grip strength. The mean follow-up period was 7.1 (range 5.3-9.9) years for all-cause and cause-specific mortality and 6.1 (4.4-9.0) years for cause-specific incidence. Of the 502,293 participants included in the respective analyses during the follow-up, 28,059 (5.6%) participants developed cardiovascular disease, 10,542 (2.1%) developed respiratory disease, and 27,704 (5.5%) developed cancer. In addition, 13,322 (2.7%) participants died: 3,033 (0.6%) from cardiovascular disease, 2,062 (0.4%) from respiratory disease, and 5,738 (1.1%) from cancer.
In women and men, respectively, hazard ratios per 5-kg lower grip strength were higher for all-cause mortality (1.20 and 1.16) and cause-specific mortality from cardiovascular disease (1.19 and 1.22), all respiratory disease (1.31 and 1.24), COPD (1.24 and 1.19), all cancer (1.17 and 1.10), colorectal cancer (1.17 and 1.18), lung cancer (1.17 and 1.08), and breast cancer (1.24) but not prostate cancer (1.05).
Muscle weakness (defined as grip strength <26 kg for men and <16 kg for women) was associated with a higher hazard for all health outcomes, except colon cancer in women and prostate cancer and lung cancer in both men and women. The addition of handgrip strength improved the prediction ability of an office-based risk score (age, sex, diabetes diagnosed, body mass index, systolic blood pressure, and smoking) for all-cause (0.013) and cardiovascular mortality (0.012) and incidence of cardiovascular disease (0.009).
“We found that grip strength had a stronger association with all cause and cardiovascular disease mortality than do systolic blood pressure or total physical activity, and that the strength of associations for grip strength with incidence of cardiovascular disease was similar to that for systolic blood pressure and stronger than for total physical activity,” the authors concluded. “Grip strength may, therefore, be a useful method of identifying people with muscle weakness who are at high risk of a wide range of diseases and who might benefit from further health assessments of risk for vascular and non-vascular outcomes.”
Celis-Morales CA, Welsh P, Lyall DM. Associations of grip strength with cardiovascular, respiratory, and cancer outcomes and all cause mortality: prospective cohort study of half a million UK Biobank participants. BMJ. 2018 May 8;361:k1651. doi: 10.1136/bmj.k1651.