A meta-analysis published in the journal Medicine (Baltimore) suggests a significant association between hypertension and knee osteoarthritis (OA).
Researchers conducted a meta-analysis of 8 observational studies (2 cohort and 6 cross-sectional) identified through a literature search on the PubMed, EMBASE, and Cochrane databases.
Hypertension was found to have a significant association with higher risk for radiographic knee OA (OR, 2.01; 95% CI, 1.28-3.15) and symptomatic knee OA (OR, 1.49; 95% CI, 1.26-1.77). The subgroup analysis by study type revealed significant associations for both cross-sectional studies (radiographic knee OA: OR, 1.85 [95% CI, 1.10-3.13] and symptomatic knee OA: OR, 1.42 [95% CI, 1.19-1.71]) and cohort studies (radiographic knee OA: OR, 2.74 [95% CI, 1.81-4.16] and symptomatic knee OA: OR, 2.17 [95% CI, 1.30-3.63]).
The precise mechanisms underlying the association have not been fully deciphered. It is possible that the 2 highly prevalent conditions share common risk factors, including aging, obesity, and chronic inflammation. IL-6 is thought to play a key role in hypertension and knee OA. Vitamin D receptor polymorphisms have also been implicated in low bone mineral density, OA, and hypertension.
"Our findings should be interpreted cautiously owing to certain shortcomings such as observational nature of studies, influence of confounding variables, no data on the effect of antihypertensive drugs, lack of subgroup analysis of knee OA stage, and possible introduction of heterogeneity," the authors warn. They call for a well-designed, community-based trial in the future to determine the true association between hypertension and OA.