Table 2.
MTHFR polymorphisms and the risk of ONFH
| Genotypes | Number of patients with ONFH (%) | Control subjects (%) (N = 200) | Odds ratio (95% CI) | ||||
|---|---|---|---|---|---|---|---|
| Total (N = 71) | Idiopathic (N = 18) | Alcohol-induced (N = 51) | Total versus control subjects | Idiopathic versus control subjects | Alcohol-induced versus control subjects | ||
| MTHFR C677T | |||||||
| CC | 18 (25.4) | 4 (22.2) | 13 (25.5) | 80 (40) | 1* | 1* | 1* |
| CT | 36 (50.7) | 8 (44.4) | 28 (54.9) | 80 (40) | 2.00 (1.05–3.81)† | 2.00 (0.58– 6.91) | 2.15 (1.04–4.46)† |
| TT | 17 (23.9) | 6 (33.3) | 10 (19.6) | 40 (20) | 1.89 (0.88–4.05) | 3.00 (0.80–11.24) | 1.54 (0.62–3.81) |
| CT + TT | 53 (74.6) | 14 (77.8) | 38 (74.5) | 120 (60) | 1.96 (1.07–3.59)† | 2.33 (0.74–7.34) | 1.95 (0.98–3.89) |
| MTHFR A1298C | |||||||
| AA | 49 (69) | 10 (55.6) | 37 (72.5) | 116 (58) | 1* | 1* | 1* |
| AC | 22 (31) | 8 (44.4) | 14 (27.5) | 78 (39) | 0.67 (0.37–1.19) | 1.19 (0.45–3.15) | 0.56 (0.29–1.11) |
| CC | 0 (0) | 0 (0) | 0 (0) | 6 (3) | ND | ND | ND |
| AC + CC | 22 (31) | 8 (44.4) | 14 (27.5) | 84 (42) | 0.62 (0.35–1.10) | 1.10 (0.42–2.92) | 0.53 (0.27–1.03) |
Two patients with steroid therapy (n = 1) and dysbarism (n = 1) were included in total patients with ONFH; *reference category (odds ratio, 1.0); †statistically significant; MTHFR = methylenetetrahydrofolate reductase; ONFH = osteonecrosis of the femoral head; CI = confidence interval; ND = not determined.