Obsessive-compulsive disorder can be a major risk of death

People with obsessive-compulsive disorder (OCD) may have an increased risk of death from both natural and unnatural causes than those without the disorder, finds a study from Sweden published by The BMJ today.

The researchers point out that many of the natural causes of death are preventable, suggesting that better surveillance, prevention, and early intervention strategies should be implemented to reduce the risk of fatal outcomes in people with OCD.

OCD is typically a long term psychiatric disorder affecting about 2% of the population. It is characterised by intrusive thoughts, urges or images that trigger high levels of anxiety and other distressing feelings - known as obsessions - that the person tries to neutralise by engaging in repetitive behaviours or rituals - known as compulsions.

OCD is also associated with academic underachievement, poor work prospects, alcohol and substance use disorders, and an increased risk of death. Previous studies on specific causes of death in OCD have mainly focused on unnatural causes (eg, suicide), but little is known about specific natural causes.

Using data from several Swedish population registers, they identified 61,378 people with OCD and 613,780 individuals without OCD matched (1:10) by sex, birth year, and county of residence, and a further sibling group of 34,085 people with OCD and 47,874 without OCD.

Average age at OCD diagnosis was 27 years and groups were monitored for an average of 8 years from January 1973 to December 2020. Overall, people with OCD had a higher death rate than matched individuals without OCD (8.1 versus 5.1 per 1,000 person years, respectively).

After adjusting for a range of potentially influential factors such as birth year, sex, county, migrant status, education and family income, people with OCD had an 82% increased risk of death from any cause. The excess risk of death was higher for both natural (31% increased risk) and, particularly, unnatural causes of death (a 3-fold increased risk).

Among the natural causes of death, people with OCD had increased risks due to respiratory system diseases (73%), mental and behavioural disorders (58%), diseases of the genitourinary system (55%), endocrine, nutritional, and metabolic diseases (47%), diseases of the circulatory system (33%), nervous system (21%), and digestive system (20%).

Reference: Obsessive-compulsive disorder linked to heightened risk of death: The BMJ; DOI:10.1136/bmj-2023-077564