Weight gain poses risk of knee osteoarthritis onset, progression

An increase in body mass index (BMI) appears to contribute to an increase in the risk of onset and worsening of knee osteoarthritis, a study has found.

Researchers looked at patients from three independent cohort studies: Osteoarthritis Initiative (OAI), Multicenter Osteoarthritis Study (MOST), and Cohort Hip and Cohort Knee (CHECK). They analysed knee radiographic data at baseline and at 4–5 years of follow-up to define the incidence of knee osteoarthritis and progression of the structural defects in individuals with the joint disease.

The incidence cohort included a total of 9,683 knees from 5,774 individuals, while the progression cohort involved 6,075 knees from 3,988 participants. Changes in BMI showed a positive association with both the incidence (adjusted odds ratio [OR], 1.05, 95 percent confidence interval [CI], 1.02–1.09) and progression of the structural defects (adjusted OR, 1.05, 95 percent CI, 1.01–1.09) of knee osteoarthritis.

Change in BMI was also positively correlated with degeneration (ie, narrowing) of joint space. The same was true for the degeneration of the femoral and tibial surfaces, as indicated by the presence of osteophytes, on the medial but not on the lateral side of the knee.

The findings suggest that weight loss could be an important strategy in preventing the onset or worsening of knee osteoarthritis.