Comorbid anxiety disorders, depression, and substance use disorders had a significant effect on the mortality among persons with OCD (Table 4). The MRRs of persons with OCD and a comorbid diagnosis of anxiety disorders or depression (2.47 [95% CI, 1.57–3.65]) and of persons with OCD and a comorbid diagnosis of substance use disorder (6.32 [95% CI, 4.26–8.97]) were higher than those of persons with only OCD (1.88 [95% CI, 1.27–2.67]). Persons with OCD and several comorbidities (ie, OCD with substance use disorder and either anxiety disorder or depression) further had an increased risk for premature mortality (MRR, 5.47 [95% CI, 3.78–7.60]). Persons with OCD and comorbid anxiety disorders or depression (MRR, 2.04 [95% CI, 1.18–3.26] for natural causes of death; MRR, 4.12 [95% CI, 1.77–7.99] for unnatural causes of death), persons with OCD and a comorbid diagnosis of substance use disorder (MRR, 4.73 [95% CI, 2.91–7.20] for natural causes of death; MRR, 15.29 [95% CI, 7.34–27.61] for unnatural causes of death), and persons with OCD and both comorbidities (MRR, 2.51 [95% CI, 1.45–4.01] for natural causes of death; MRR, 29.38
