Background: There is growing evidence that mast cells (MCs) play a role in knee osteoarthritis (OA). H1-antihistamines block H1-receptors of histamine, which is an important mediator of MCs. There is a lack of data on whether H1-antihistamines can influence OA. We hypothesized that the use of H1-antihistamines may be linked to the reduced prevalence of knee OA.
Methods: Baseline data from the Osteoarthritis Initiative cohort were analysed cross-sectionally. Unadjusted and adjusted logistic regression models were performed to compare the prevalence of knee OA in H1-antihistamine users and non-users. Generalized estimating equations were used to adjust for the correlation between knees. Knee OA was defined as (1) Kellgren-Lawrence (KL) grade ≥ 2 or total joint replacement or (2) KL grade ≥ 2 and joint space narrowing or total joint replacement.
Results: The analysed sample consisted of 8545 knees (664 knees of H1-antihistamine users and 7881 knees of H1-antihistamine non-users). The use of H1-antihistamines was associated with reduced prevalence of knee OA in unadjusted and adjusted models using both the first (adjusted OR, 0.77; 95% CI, 0.62, 0.96; P < 0.02) and second (adjusted OR, 0.75; 95% CI, 0.62, 0.93; P < 0.008) definitions of knee OA.
Conclusions: H1-antihistamines are associated with a reduced prevalence of knee OA. The findings indicate that this class of drugs should be further evaluated for possible structure-modifying properties in knee OA.
Keywords: Knee osteoarthritis; Osteoarthritis; Outcomes research.