Comorbid mental disorders, general medical conditions linked with mortality

Individuals with comorbid mental disorders and general medical conditions had increased risk for premature mortality, according to findings published in JAMA Psychiatry.

“Our findings highlight that individuals with mental disorder–general medical condition (GMC) comorbidity have an increased risk of dying; their life expectancy is shorter than that of both the entire population and people with either mental disorders or GMCs only,” Natalie C. Momen, PhD, an epidemiologist at Aarhus University in Denmark, and colleagues wrote.

Momen and colleagues designed a population-based cohort study assessing 5,946,800 individuals (2,961,397 men; 2,985,403 women) born in Denmark between 1900 and 2015 with a median age of 32 years (7.3-52.9) at the start of follow-up (Jan. 1, 2000, or their date of birth) and 48.9 years (42.5-68.8) at the end.

The researchers calculated mortality rate ratios (MRRs) and differences in life expectancy by investigating various pairs of mental disorders and general medical conditions (GMCs) to “assess the association of mortality with both disorders of interest compared with the mental disorder of interest, the general medical condition of interest and neither disorder of interest.”

According to the study, the mean MRR, determined by Cox proportional hazards models with age as the underlying time scale, compared with individuals without mental disorders or GMCs was 5.90 (median, 4.94; range, 2.05-18.55; IQR, 3.80-7.30) based on all pairs of comorbid mental disorders and GMCs. Additionally, compared with the general population, the mean reduction of life expectancy was 11.35 years (median, 11.08; range, 5.27-23.53; IQR, 8.22-13.72).

Momen and colleagues noted that an addition of a neurological disorder in patients with an existing mental disorder was associated with a mean MRR of 1.22, compared with 4.07 for all mental disorders with the addition of cancer.

According to the study, multimorbidity between mental disorders and GMCs is increasing and “challenging health care systems globally,” making early identification and management of mental disorders and GMCs important for lowering the risk of death.

“We hope these estimates provide a foundation for future research aiming to improve life expectancy among people with comorbidity,” Momen and colleagues wrote. “They highlight the need to optimize screening for GMCs among people with mental disorders so comorbidity can either be prevented or identified early and managed well.”