TUESDAY, Aug. 18, 2026 (HealthDay News) -- People with schizophrenia-spectrum or bipolar disorder have increased relative and absolute incidence of systemic physical multimorbidity, according to a study published in the September issue of The Lancet Psychiatry.Sean Halstead, M.D., from the Metro South Addiction and Mental Health Service in Brisbane, Australia, and colleagues conducted a cohort study involving individuals with a recorded diagnosis of schizophrenia-spectrum or bipolar disorder who were age- and sex-matched (1:4) to individuals without these disorders (30,189 patients and 148,476 hospital comparators). Systemic physical multimorbidity, defined as the cumulative number of systems affected by chronic physical disease, was examined as the study outcome.The researchers found that the disorder group had a higher relative incidence for increasing levels of systemic physical multimorbidity, with adjusted subdistribution hazard ratios of 1.85, 2.25, 2.65, 2.93, and 3.16 for at least one, at least two, at least three, at least four, and at least five affected systems, respectively. The absolute cumulative incidence differences at 20 years were 9.79, 18.43, 18.57, 15.71, and 11.66 additional cases per 100 persons for at least one, at least two, at least three, at least four, and at least five affected systems, respectively. For younger strata, elevated adjusted subdistribution hazard ratios were consistently observed, with the highest seen in women younger than 25 years with at least five affected systems (adjusted subdistribution hazard ratio, 9.24)."People have assumed the shorter life expectancy associated with schizophrenia or bipolar disorder is mostly due to suicide, but much of the gap is actually driven by physical illnesses, many of which are preventable or treatable," Halstead said in a statement. "We need to stop thinking about schizophrenia and bipolar disorder as mental health conditions that exist in isolation."Several authors disclosed ties to the biopharmaceutical industry.Abstract/Full Text.Sign up for our weekly HealthDay newsletter