Can losing weight combat the structural defects of knee osteoarthritis?

In a study published in Arthritis & Rheumatology, a decrease in body mass index (BMI) was associated with both a lower incidence of the structural defects of knee osteoarthritis and a lower likelihood that such defects would progress, or get worse.

Researchers examined radiographic analyses of knees at baseline and at 4 to 5 years' follow up from adults with and without the structural defects of knee osteoarthritis at the start of the study. The team assessed 9,683 knees (from 5,774 individuals) in an 'incidence cohort' and 6,075 knees (from 3,988 individuals) in a 'progression cohort.'

A 1-unit decrease in BMI corresponded to a 4.76% reduction in odds of the incidence and progression of knee osteoarthritis; however, a 5-unit decrease in BMI, which is an amount that can lead to a reduction in BMI category (for example., from overweight to normal), reduced the odds of incidence and progression by 21.65%.

"These findings could be empowering for people with or at risk of knee osteoarthritis," said lead author Zubeyir Salis, BEng, and a Ph.D. student for Public Health at the University of New South Wales in Australia. "The current prevailing view is that knee osteoarthritis is part of aging and that we have no control over it. However, my analyses suggest that some people could potentially prevent, slow or delay knee osteoarthritis by losing weight."