PTH and obesity due to melanocortin 4 receptor deficiency: Table 3 shows the results of multivariate logistic regression with stepwise selection. Obesity was a significant factor that affected the incidence of PTH after adjusting for sex and etiology of obstructive SAS (odds ratio, 4.55; 95% confidence interval, 1.10–18.8; p = 0.036; Table 3).