Big waist ups low physical function risk in adults with knee OA

A growing waistline increases the risk of incident low physical function in the following year among adults with knee osteoarthritis (OA), suggests a recent study. Maintaining waist circumference (WC) may prevent the development of low physical function.

The investigators used data from the Osteoarthritis Initiative, measuring change in WC from study enrolment (0 month) to the 96-month visit and classifying as increase (≥5-cm gain) or maintain (<5-cm gain). The World Health Organization (WHO) risk category was identified based on WC at study enrolment as either large (males ≥102 cm; females ≥88 cm) or small (males <102 cm; females <88 cm).

Incident low physical function was defined as ≥28 Western Ontario and McMaster Universities Osteoarthritis Index physical function subscale. Risk ratios were calculated and adjusted for potential confounders to assess the association of the 8-year change in WC with the risk of low physical function. The investigators repeated the analyses stratified by the WHO disease risk category.

Adults in the increased WC group had a 43-percent (95 percent confidence interval [CI], 1.04–1.96) higher risk of incident low physical function than those in the maintained WC group.

Participants with a large WC at baseline who increased WC had a 55-percent (95 percent CI, 1.00–2.37) higher risk of incident low physical function than those who maintained their WC. Furthermore, adults with a small WC at baseline who increased WC had a 97-percent (95 percent CI, 0.84–4.63) higher risk compared to those who maintained WC.