Association of Hypertension with Knee Pain Severity Among People with Knee Osteoarthritis

Purpose: To examine the association of hypertension with knee pain severity in individuals with knee osteoarthritis (OA).

Design: Cross-sectional study of baseline data collected by the Osteoarthritis Initiative.

Methods: Participants with knee OA (N=1,363) were categorized into four groups based on blood pressure (BP): 1) systolic < 120 mm HG and diastolic < 80 mm Hg; 2) 120 ≤ systolic < 130 mm Hg and diastolic < 80 mm Hg; 3) 130 ≤ systolic < 140 mm Hg or 80 ≤ diastolic < 90 mm Hg; 4) systolic ≥ 140 mm Hg or diastolic ≥ 90 mm Hg. OA knee pain severity was measured by Pain subscale of Western Ontario and McMaster Universities Osteoarthritis Index in the past 48 hours, Pain subscale of Knee Injury and Osteoarthritis Outcome Score (KOOS) in the past 7 days, and numeric rating scale (NRS) in the past 30 days. Linear regression was used to examine the relationship between hypertension and knee pain severity.

Results: Compared with the normal BP group, individuals with stage 2 hypertension reported significantly higher OA knee pain severity by KOOS in the past 7 days (β=-2.05 [95% CI -4.09, -0.01], p=0.049) and by NRS in the past 30 days (β=0.31 [95% CI 0.01, 0.62], p=0.045) after adjustments for demographic and medical factors.

Conclusions: Hypertension was associated with higher OA knee pain severity in individuals with knee OA.

Clinical implications: Nurses can recommend adjunctive non-pharmacological treatments and adherence strategies to help control hypertension, which may help decrease OA knee pain.