The multivariate analysis demonstrated that female sex [odds ratio (OR), 1.17; 95% confidence interval (CI), 1.03-1.33; P = .02] and combination therapy of anti-PD-1 and anti-CTLA-4 (compared with anti-PD-1 monotherapy, OR, 1.91; 95% CI, 1.47-2.49; P < .01) were associated with an increased risk for developing hypothyroidism (Fig. 2). This evidence concerns the gene CTLA4 and hypothyroidism.