OBJECTIVE: We investigated the burden of chronic kidney disease (CKD) among patients with
severe mental illness (SMI).
METHODS: We identified patients with SMI among all those aged 25–74 registered in the UK
Clinical Practice Research Datalink as on March 31, 2014. We compared the prevalence of CKD
(two measurements of estimated glomerular filtration rate <60 mL/min/1.73 m2
for ≥3 months)
and renal replacement therapy between patients with and without SMI. For patients with and
without a history of lithium prescription separately, we used logistic regression to examine the
association between SMI and CKD, adjusting for demographics, lifestyle characteristics, and
known CKD risk factors.
RESULTS: The CKD prevalence was 14.6% among patients with SMI and a history of lithium
prescription (n = 4,295), 3.3% among patients with SMI and no history of lithium prescription
(n = 24,101), and 2.1% among patients without SMI (n = 2,387,988; P < 0.001). The prevalence
of renal replacement therapy was 0.23%, 0.15%, and 0.11%, respectively (P = 0.012). Compared
to patients without SMI, the fully adjusted odds ratio for CKD was 6.49 (95% CI 5.84–7.21) for
patients with SMI and a history of lithium prescription and 1.45 (95% CI 1.34–1.58) for patients
with SMI and no history of lithium prescription. The higher prevalence of CKD in patients with SMI
may, in part, be explained by more frequent blood testing as compared to the general population.
CONCLUSION: CKD is identified more commonly among patients with SMI than in the general
population
