Prevalence of chronic kidney disease in people with severe mental illness: systematic review and meta-analysis

Background People with severe mental illness (SMI) are more likely to develop long-term physical health conditions compared with those without SMI, contributing to an inequality in life expectancy. Chronic kidney disease (CKD) is a growing global health concern set to be the fifth leading cause of life-years lost by 2040. Although people with SMI may have a higher risk of CKD, there is limited research exploring the relationship between CKD and SMI. Aims This review aimed to examine the prevalence, incidence and risk of CKD among people with SMI. Method We searched Medline, Embase, PsycINFO, CINAHL, Scopus and Web of Science for epidemiological research reporting the prevalence of CKD (of any stage according to Kidney Disease Improving Global Outcomes guidelines) among people with SMI. Records were imported into Covidence and screened by two reviewers. Meta-analyses were conducted using random-effects models to examine the prevalence, incidence and risk of CKD among people with SMI. Results Forty-eight studies were included in the review. The pooled prevalence of CKD was 8% in studies of people with SMI (95% CI 5%, 18%) and was highest in studies focused only on participants with bipolar disorder (95% CI 0.15 (0.06, 0.26)). The pooled incidence rate of CKD was 26.83 cases (95% CI 18.66, 38.58) per 1000 person-years. People with SMI had significantly higher odds of CKD compared with those without SMI (odds ratio 2.33 [95% CI 1.70, 3.21]). Conclusion People with SMI are at a significantly higher risk of having CKD compared with those without SMI. Although psychiatric medication and high rates of diabetes may play a role, the drivers of this inequality are under-researched.