Effects of chronic lithium treatment on renal function

IntroductionLithium treatment is associated with renal side effects which vary from mild nephrogenic diabetes insipidus to end stage renal disease (ESRD). A review of the literature suggests that ESRD is a very rare side effect, caused after very long-term lithium treatment, and that it might be preventable if lithium is stopped early.MethodsSixty-one patients were treated with lithium for a mean of 15.6 years (range 3–32, SD = 6.4). Their kidney function was monitored at an Affective Disorders Clinic for a mean of 11.5 years (range 2–29, SD = 5.4). We estimated their glomerular filtration rate (eGFR) at the end of monitoring. As a control group we used 53 patients who received ECT at our hospital, and had not taken lithium, and nine patients from the same clinic who were taking other mood-stabilisers.ResultsLithium patients had lower eGFR compared to controls: 66.1 vs. 75.0 mL/min/1.73 m2, p = 0.0006 after controlling for age and gender. The percentage of patients with an eGFR < 60 ml/min/1.73 m2 (grade 3 chronic kidney disease) was 34.4%, vs. 13.1% in the controls, and was much increased compared to the general population in the respective age ranges. There was a modest but non-significant correlation between the number of years that patients had taken lithium and their eGFR, (beta = − 0.177, B = − 0.43, p = 0.1). One patient reached an eGFR of 28 mL/min/1.73 m2 and her lithium was stopped. One patient required dialysis 6 years after leaving the clinic.ConclusionsLithium causes a modest decline in renal function. However the available research suggests that ESRD is a very rare complication of long-term lithium treatment, affecting ∼ 1% of patients who have taken lithium for over 15 years.