Renal glomerular function and long-term lithium therapy.

Recently published studies vary widely in the quantitative assessment of glomerular filtration rate (GFR) in lithium-treated patients. Therefore, the authors tested 99 lithium-treated manic-depressive patients using several techniques to measure GFR. Ten of 86 patients who had no history of renal disease had mildly low creatinine clearance values. Significant correlations, which were not age-related, between the serum creatinine, Cockroft creatinine clearance, and duration of lithium therapy suggest a relationship between chronic lithium therapy and declining GFR. Since serum creatinine alone was insensitive, the authors recommend the use of duplicate classical creatinine clearances confirmed by Cockroft values to monitor GFR during lithium treatment.