People with severe mental disorders have ‘persistent mortality gap’

Compared with the general population, individuals with mental disorders had increased risk for mortality across all disorders, according to results of a systematic review and meta-regression published in Journal of Psychiatric Research.

“One of the major limitations of previous quantitative systematic reviews is the use of meta-analytic models to synthesize mortality estimates without taking into account potential sources of heterogeneity between studies,” Suhailah Ali, of the school of public health at the University of Queensland in Australia, and colleagues wrote. “This can include study-level factors such as population type (ie, inpatients, outpatients, community-based) and follow-up time, as well as population-level factors such as sex and age. Meta-regression models can quantify and adjust for such variation between studies using covariates, thereby removing potential sources of bias from the interpretation of findings.”

Ali and colleagues sought to improve upon prior analytic approaches to account for possible sources of heterogeneity in pooled mortality estimates. They conducted a systematic review of studies that investigated excess mortality among individuals with psychotic disorders and bipolar disorders, searching three databases between Jan. 1, 1980, and Dec. 31, 2020. They included longitudinal studies with study populations diagnosed according to established criteria, without restricting to subgroups. Additional inclusion criteria were studies in which the disorder was primary and not acute or transient, as well as those that reported mortality compared with the general population or a control group without severe mental disorder.

Researchers used meta-regression models to calculate pooled RRs for all-cause and cause-specific mortality adjusted for study- and population-level covariates. Further, they assessed risk for bias via an adaptation of the Newcastle-Ottawa scale.

Ali and colleagues included 76 studies in the analyses, with covariates in the final models including age, sex, population type and mid-year. Results showed an adjusted RR for all-cause mortality of 2.89 (95% CI, 2.5-3.34) for schizophrenia and 2.51 (95% CI, 2.1-3) for bipolar disorder. RRs were larger for broader categories of psychotic disorders. Researchers noted elevated morality in each cause of death examine. They could not account for most of the heterogeneity between studies.

“There is a persistent mortality gap for people with [severe mental disorders] compared to the general population, with risks varying over the lifespan and over time, between diagnoses and, in some cases, between sexes and in different patient settings,” Ali and colleagues wrote. “It is therefore important to take a nuanced view of this problem, considering individuals with their unique case histories situated in a particular health system and social context, to provide each person with the specific care and support they require.”