Table 4.

Association between physical activity and risk of primary hip replacement.

Total Population, n = 39,023Sensitivity Analysis on Participants with Complete 2nd Followup Data, n = 27,323
Hazard Ratio (95% CI)pHazard Ratio (95% CI)p
Total physical activity level
  None (0)1.001.00
  Low (> 0–3)0.76 (0.56, 1.03)0.070.71 (0.50, 1.02)0.07
  Moderate (> 3–4)0.89 (0.67, 1.16)0.380.84 (0.61, 1.17)0.30
  High (> 4)1.09 (0.84, 1.41)0.521.13 (0.84, 1.52)0.42
  Trend test*1.03 (1.00, 1.06)0.09NANA
Vigorous activity**
  None at all1.001.00
  1–2 times/week1.11 (0.83, 1.48)0.491.19 (0.87, 1.63)0.27
  ≥ 3 times/week1.27 (0.94, 1.73)0.121.32 (0.95, 1.86)0.10
  Trend test1.06 (0.99, 1.14)0.111.08 (0.99, 1.17)0.07
Less vigorous activity**††
  None at all1.001.00
  1–2 times/week1.04 (0.80, 1.36)0.761.04 (0.76, 1.42)0.82
  ≥ 3 times/week1.09 (0.83, 1.41)0.551.10 (0.81, 1.50)0.54
  Trend test1.02 (0.96, 1.09)0.541.02 (0.95, 1.11)0.54
Walking**††
  None at all1.001.00
  1–2 times/week0.75 (0.55, 1.03)0.070.71 (0.49, 1.03)0.07
  ≥ 3 times/week0.97 (0.77, 1.21)0.780.96 (0.74, 1.25)0.77
  Trend test*1.00 (0.94, 1.06)0.93NANA
  • * No evidence of linear association found between total physical activity level or walking and the risk of hip replacement (likelihood ratio test, p = 0.05), thus no trend test results presented.

  • Adjusted for age, gender, body mass index, country of birth, occupational physical activity, and education level.

  • ** Weekly frequency of physical activity undertaken for at least 20 minutes.

  • †† Analysis excluding those reporting vigorous activity. NA: not applicable.