Meta-analysis showed a significantly increased risk for addiction in ADHD (n = 23, odds ratio [OR] 2.27, 95% CI 1.98-3.67; OR alcohol 2.15, 95% CI 1.56-2.97; OR drugs 1.52, 95% CI 1.52-5.27; OR nicotine 2.52, 95% CI 2.01-3.15; OR SUDs 2.61, 95% CI 1.77-3.84), ODD or CD (n = 8, OR 3.18, 95% CI 1.97-5.80; OR alcohol 1.73, 95% CI 1.51-2.00; OR drugs 4.24, 95% CI 1.3.21.5.59; OR nicotine 4.22, 95% CI 3.21-5.55; OR SUDs 4.86, 95% CI 3.09-7.56), and depression (n = 13, OR 2.03, 95% CI 1.47-2.81; OR alcohol 1.10, 95% CI 1.02-1.19; OR nicotine 2.56, 95% CI 1.89-3.48; OR SUDs 2.20, 95% CI 1.41-3.43), but not for anxiety disorders (n = 15, OR 1.34, 95% CI 0.90-1.55, not significant).