Association of blood pressure with knee pain progression over 4 years in middle-aged and elderly individuals with or at risks for osteoarthritis: data from the Osteoarthritis Initiative.

OBJECTIVE

To investigate the association between blood pressure and knee pain progression in individuals with or at risk for osteoarthritis (OA).

METHOD: This retrospective, multicenter, cohort study utilized a total of 2906 subjects (61.7% female, aged 45-79 years) from the Osteoarthritis Initiative. Blood pressure parameters included diastolic blood pressure, systolic blood pressure, pulse pressure (PP), and hypertension stage. Knee pain severity was measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Knee Injury and Osteoarthritis Outcome Score, and the Numeric Rating Scale. Binary logistic regression was conducted to evaluate associations between blood pressure parameters and knee pain progression. Sensitivity analyses were performed for significant findings using exposure quartiles, multiple imputation, and linear regression of continuous pain score changes. Potential effect modification was tested using interaction analyses.

RESULTS

Elevated PP was significantly associated with weight-bearing WOMAC pain progression (Odd ratio = 1.09, 95% Confidence Interval: 1.02-1.17, p = 0.014). The association remained significant in sensitivity analyses using PP quartiles (trend p = 0.011) and multiple imputation (OR = 1.08, 95% CI: 1.01-1.16, p = 0.021). No significant interactions were detected between PP and sex, body mass index, diabetes, Kellgren-Lawrence grade, pain management treatment, and antihypertensive medication use.

CONCLUSIONS

This study revealed a significant relationship between PP and the weight-bearing knee pain progression in individuals with or at risk for primary OA, suggesting a vascular factor in OA pathogenesis. Limitations include the observational design and potential residual confounding. Key Points • Elevated pulse pressure is associated with weight-bearing knee pain progression. • A threshold-like association was observed, with a significant effect at higher pulse pressure levels.