Table III.
Characteristics of responders and nonresponders to one-year patient-reported outcome measures (PROMs)
| Variable | Hips | Knees | ||||
|---|---|---|---|---|---|---|
| Nonresponder (n = 518) | Responder (n = 1555) | p-value | Nonresponder (n = 452) | Responder (n = 1697) | p-value | |
| Mean age, yrs (sd) | 65.6 (11.1) | 68.0 (11.7) | < 0.001*† | 68.1 (10.2) | 69.7 (9.3) | 0.002*† |
| Mean body mass index, kg/m2 (sd) | 29.5 (6.3) | 28.2 (5.5) | < 0.001*† | 31.7 (6.4) | 30.6 (5.6) | < 0.001*† |
| Sex, female, n (%) | 318 (61) | 935 (60) | 0.618‡ | 174 (38) | 753 (44) | 0.004†‡ |
| Medical comorbidity, n (%) | ||||||
| Myocardial infarction | 22 (4) | 49 (3) | 0.235‡ | 31 (7) | 73 (4) | 0.040†‡ |
| Heart failure | 5 (1) | 11 (1) | 0.561‡ | 3 (1) | 17 (1) | 0.466‡ |
| Peripheral arterial disease | 5 (1) | 25 (2) | 0.298‡ | 9 (2) | 34 (2) | 0.902‡ |
| Stroke with hemiplegia | 12 (2) | 39 (3) | 0.808‡ | 20 (4) | 36 (2) | 0.01†‡ |
| Dementia | 4 (1) | 17 (1) | 0.527‡ | 3 (1) | 6 (1) | 0.396‡ |
| Chronic obstructive pulmonary disease | 32 (6) | 58 (4) | 0.018†‡ | 28 (6) | 66 (4) | 0.052‡ |
| CTD/inflammatory arthropathy | 76 (15) | 161 (10) | 0.007†‡ | 97 (21) | 269 (16) | 0.014†‡ |
| Diabetes | 49 (9) | 119 (8) | 0.192‡ | 62 (14) | 207 (12) | 0.565‡ |
| Kidney disease | 8 (2) | 31 (2) | 0.515‡ | 13 (3) | 37 (2) | 0.455‡ |
| Liver disease | 8 (2) | 24 (1) | 0.999‡ | 8 (2) | 20 (1) | 0.374‡ |
| Median number of medical comorbidities (IQR) | 0 (0 to 1) | 0 (0 to 2) | < 0.001†§ | 2 (1 to 3) | 0 (0 to 1) | < 0.001†§ |
| Musculoskeletal comorbidity, n (%) | ||||||
| Back pain | 274 (53) | 725 (47) | < 0.013†‡ | 214 (47) | 653 (38) | 0.006†‡ |
| Pain in other joints | 358 (69) | 1020 (66) | < 0.015†‡ | 341 (75) | 1179 (69) | 0.202 |
| Preoperative PROM | ||||||
| Median EQ-5D index (IQR) | 0.16 (-0.02 to 0.62) | 0.516 (0.09 to 0.69) | < 0.001†§ | 0.20 (0.06 to 0.69) | 0.59 (0.16 to 0.69) | < 0.001†§ |
| Mean EQ-5D health (sd) | 63.4 (23.7) | 68.7 (21.5) | < 0.001*† | 67.0 (21.1) | 70.5 (20.4) | < 0.001*† |
| Mean EQ-5D pain (sd) | 47.5 (24.5) | 52.0 (23.2) | < 0.001*† | 50.2 (23.4) | 52.3 (22.3) | 0.076* |
| Mean preoperative Oxford score | 17.5 (8.5) | 20.4 (8.5) | < 0.001*† | 18.0 (7.8) | 20.7 (7.8) | < 0.001*† |
*
Unpaired Student’s t-test
†
Statistically significant
‡
Chi-squared test
§
Mann–Whitney U test
CTD, connective tissue disorder; IQR, interquartile range