Table 1.
Comparison of baseline characteristics in HBM cases and controls
| Descriptive characteristic | HBM cases | Controls | P valuea |
|---|---|---|---|
| Age (years), mean (s.d.) | 61.7 (13.8) | 54.1 (16.2) | <0.001 |
| BMI (kg/m2), mean (s.d.) | 30.5 (5.9) | 28.0 (4.8) | <0.001 |
| Sum hip and L1 Z-scores, mean (s.d.) | 6.96 (2.2) | 0.98 (1.8) | <0.001 |
| Max total hip Z-score (n = 529), mean (s.d.) | 3.00 (1.2) | 0.53 (0.9) | <0.001 |
| L1 Z-score (n = 542), mean (s.d.) | 3.92 (1.5) | 0.48 (1.2) | <0.001 |
| Female | 270 (76.5) | 92 (46.7) | <0.001 |
| Post-menopausal | 218 (82.9) | 48 (54.6) | <0.001 |
| Oestrogen replacement (ever) | 128 (52.7) | 15 (19.2) | <0.001 |
| Prior fractureb | 134 (38.0) | 90 (45.7) | 0.077 |
| Any joint replacement risk factor (not OA)c | 24 (6.8) | 3 (1.5) | 0.006 |
| English IMD quartiles (n = 496)d | |||
| 1 (most deprived) | 38 (11.9) | 18 (10.2) | |
| 2 | 68 (21.3) | 36 (20.3) | 0.909 |
| 3 | 100 (31.4) | 56 (31.6) | |
| 4 (least deprived) | 113 (35.4) | 67 (37.9) |
Results presented as n (%) unless otherwise indicated. n = 550 (i.e. 353 cases and 197 controls) except where stated. aP values shown from t-test (continuous variables) and χ2 test (categorical variables) comparing HBM cases with controls. bAny lifetime fracture regardless of mechanism. cIncludes RA (n = 17), AS (n = 2), SLE with joint involvement (n = 2), PsA (n = 5), steroid-induced avascular necrosis leading to hip replacement (n = 1). dQuartiles of IMD ranks compared with the whole of England (1–32 482), 1: most deprived.