Alcohol intake and the risk of osteonecrosis of the femoral head in Japanese populations: a dose-response meta-analysis of case-control studies.

Studies examining the association between alcohol intake and the risk of osteonecrosis of the femoral head (ONFH) have inconsistent results. The purpose of this study was to examine and summarize the evidence regarding the association between alcohol intake and ONFH based on results from case-control studies. This analysis included five case-control studies reporting data from 1251 individuals. Alcohol intake habits (never, former, or current), average drinking consumption (g/week), and cumulative drinking consumption (drink-years) were extracted. The risk of ONFH was evaluated, and a two-stage dose-response meta-analysis was performed using restricted cubic splines with four knots at fixed percentiles of 5, 35, 65, and 95% of the distribution. Former alcohol intake increased the risk of ONFH with a marginal significance (odds ratio [OR], 2.62; p = 0.055). Current alcohol intake was associated with an increased risk of ONFH (OR, 3.63; p < 0.001 in occasional drinkers, OR, 5.90; p < 0.001 in daily drinkers). The dose-response meta-analysis revealed that the risk of ONFH increased by 35.3% for every 100 g/week (95% confidence interval [CI], 1.24-1.47; p < 0.001) and by 44.1% for every 500 g drink-years (95% CI, 1.295-1.601; p < 0.001). Current intake and the dose of alcohol were positively associated with an increased risk of ONFH in a non-linear pattern.