Effects of chronic physical illness on treatment outcomes among patients with schizophrenia

Previous research has demonstrated the high prevalence of medical comorbidity and multimorbidity among patients with schizophrenia. However, little is known regarding the potential effects of chronic physical illness (CPI) on schizophrenia treatment outcomes. In the present report, we aim to provide an updated review of the relevant literature.

We searched MEDLINE for studies published between 2017 and 2018. After screening 683 articles, we included six studies of adequate quality. Five of these studies reported significant associations between several CPIs and different schizophrenia treatment outcomes, whereas the remaining study did not. Significant effects were low to moderate in size. CPIs with significant effects on treatment outcomes included metabolic syndrome, cardiovascular disease, and asthma. No significant effects were observed for diabetes, chronic obstructive pulmonary disease, hepatitis, hypertension, hyperlipidemia, or lung conditions. One study reported a significant association between the total number of CPIs and the overall number of psychiatric rehospitalizations.

In addition to increasing the risk of premature mortality, accumulating evidence indicates that various CPIs affect schizophrenia treatment outcomes. Thus, researchers and healthcare practitioners should increase efforts to raise awareness regarding the importance of physical health among patients with schizophrenia. Further high-quality studies are required, particularly those targeting the potential effects of individual CPIs.