Excess resource use and costs of physical comorbidities in individuals with mental health disorders: A systematic literature review and meta-analysis.

Individuals with mental health disorders (MHDs) have worse physical health than the general population, utilise healthcare resources more frequently and intensively, incurring higher costs. We provide a first comprehensive overview and quantitative synthesis of literature on the magnitude of excess resource use and costs for those with MHDs and comorbid physical health conditions (PHCs). This systematic review (PROSPERO CRD42017075319) searched studies comparing resource use or costs of individuals with MHDs and comorbid PHCs versus individuals without comorbid conditions published between 2007 and 2021. We conducted narrative and quantitative syntheses, using random-effects meta-analyses to explore ranges of excess resource use and costs across care segments, comparing to MHD only, PHC only, or general population controls (GPC). Of 20,075 records, 228 and 100 were eligible for narrative and quantitative syntheses, respectively. Most studies were from the US, covered depression or schizophrenia, reporting endocrine/metabolic or circulatory comorbidities. Frequently investigated healthcare segments were inpatient, outpatient, emergency care and medications. Evidence on lost productivity, long-term and informal care was rare. Substantial differences exist between MHDs, with depressive disorder tending towards lower average excess resource use and cost estimates, while excess resource use ranges between +6% to +320% and excess costs between +14% to +614%. PHCs are major drivers of resource use and costs for individuals with MHDs, affecting care segments differently. Significant physical health gains and cost savings are potentially achievable through prevention, earlier identification, management and treatment, using more integrated care approaches. Current international evidence, however, is heterogeneous with limited geographical representativeness and comparability.