Does the association between physical capability and mortality differ by deprivation? Findings from the UK Biobank population-based cohort study

ABSTRACT

Background

To investigate whether the excess risk of adverse health outcomes associated with a lower physical capability in adulthood differs by deprivation levels.

Methods

279,030 participants from the UK Biobank were included. Handgrip strength and walking pace were the exposures. All-cause mortality, CVD mortality and incidence were the outcomes. Townsend deprivation index was treated as a potential effect modifier. The associations were investigated using Cox-regression models with years of follow-up as the time-varying covariate.

Results

A significant interaction between deprivation and handgrip strength was found for all-cause mortality (p = 0.024), CVD mortality (p = 0.006) and CVD incidence (p = 0.001). The hazard ratio for all-cause mortality was 1.18 [1.09; 1.29] per 1-tertile higher level of grip strength in the least deprived group, whereas it was 1.30 [1.18; 1.43] in the most deprived individuals. Similar results were found for CVD mortality and incidence per tertile increment in handgrip strength in the least and most deprived quintiles, respectively. No significant interactions between deprivation and walking pace were found for any of the outcomes.

Conclusion

Low handgrip strength is a stronger predictor of morbidity and mortality in individuals living in more deprived areas.

KEYWORDS:

• Mortality
• incidence
• muscle strength
• cardiovascular diseases

Acknowledgments

UK Biobank was established by the Wellcome Trust medical charity, Medical Research Council, Department of Health, Scottish Government and the Northwest Regional Development Agency. It has also had funding from the Welsh Assembly Government and the British Heart Foundation. All authors had final responsibility for submission for publication.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data for this article can be accessed online https://doi.org/10.1080/02640414.2020.1797438.

Additional information

Funding

JPRL receives financial support from the University of Sydney Deputy-Vice Chancellor Post-doctoral Research Fellowship (Project Code: U2334). For the purpose of this work, JPRL received a grant of the University of Sydney-University of Glasgow Early Career Mobility Scheme in January 2018. We are grateful to UK Biobank participants. This research has been conducted using the UK Biobank resource under application number 7155.