Schizophrenic patients have been found to die at an earlier age than the normal population.5 This was true whether the patient had one attack of the mental disorder, recovered and was discharged, and died later out of the mental hospital, or whether he was continuously hospitalized after the onset of the disease. The former died at an age of death closer to the normal than the latter. Patients having multiple admissions and releases dying in or out of the mental hospital fell between the above two groups.
These findings prompted a second study, this one cross sectional, which revealed that four different groups of schizophrenic patients had the same causes of death over a 30-year span as did the normal population.4 Deaths in each group consistently occurred at a younger age compared to that of the normal population.
Two other interesting data were found.
NISWANDER GD, HASLERUD GM, MITCHELL GD. Effect of Catatonia on Schizophrenic Mortality. Arch Gen Psychiatry. 1963;9(6):548-551. doi:10.1001/archpsyc.1963.01720180020003