Table 5

Patient-reported outcome comparisons by BMI group.

OutcomeMean ± SD (n) R 2 P Valuea
Nonobese
(N = 74)
Obese I
(N = 27)
Obese II
(N = 19)
Obese III
(N = 8)
PROMIS-PF
 Preoperative40.7 ± 6.6 (74)38.6 ± 8.8 (27)38.6 ± 5.7 (19)39.4 ± 7.8 (8)0.0210.458
 6 wk42.5 ± 6.6 (53)39.6 ± 7.9 (17)39.2 ± 7.4 (15)39.3 ± 6.7 (7)0.0480.220
 12 wk45.3 ± 8.7 (47)49.7 ± 13.0 (15)40.8 ± 5.5 (13)43.9 ± 13.5 (4)0.0770.109
 6 mo47.9 ± 9.1 (41)51.7 ± 11.3 (11)41.1 ± 6.7 (11)44.5 ± 7.3 (3)0.1140.060
1 y 50.5 ± 7.8 (35) 50.8 ± 9.5 (10) 43.0 ± 6.5 (8) 42.2 ± 6.9 (4) 0.149 0.035
2 y 51.3 ± 7.9 (25) 45.5 ± 9.1 (10) 41.7 ± 5.0 (9) 42.5 ± 13.1 (6) 0.205 0.014
PROMIS-PF
 6 wk Δ2.2 ± 6.5-0.93 ± 10.00.35 ± 7.50.24 ± 10.00.0270.476
12 wk Δ 4.1 ± 7.6 10.1 ± 10.4 1.8 ± 7.3 4.3 ± 7.3 0.101 0.044
 6 mo Δ7.3 ± 6.89.8 ± 9.34.2 ± 5.37.5 ± 7.60.0530.331
 1 year Δ9.0 ± 8.010.5 ± 10.94.9 ± 5.05.0 ± 5.00.0550.388
2 year Δ 9.9 ± 7.0 7.1 ± 8.5 2.3 ± 5.5 3.0 ± 11.7 0.156 0.048
  • aP value was calculated using linear regression (continuous) to compare each time point among subgroups.

  • BMI, body mass index; PROMIS-PF, Patient Reported Outcome Measurement Information System physical function.