Bendz H, Sjodin I, Aurell M
Renal function on and off lithium in patients treated
with lithium for 15 years or more. A controlled, prospective lithium
withdrawal study.
Nephrol Dial Transplant
(Mar) 11:457-460 1996

Controversy around the long term nephrotoxic effects of lithium
continues with conflicting results from observational studies.This
case-control prospective study compared renal function in 13
patients who had been on lithium for at least 15 years, and at 5 and 9
weeks after stopping treatment, with 13 controls with an affective
disorder not treated with lithium and who were matched for age and
sex. Serum lithium values before 1977 were unreliable and mean serum
lithium concentration after that period was 0.66 (0.30 - 0.90)
meq/l.The results show no differences in serum creatinine (lithium
patients on lithium, mean ( SEM (range) 103 ( 6 (mol/l (73-161), off
lithium 97 ( 7 (73-163), controls 86 ( 4 (66-108), or GFR (lithium
patients on lithium 69 ( 4 ml/min/1.73m2 (39-96), off lithium 74 ( 4
(39-94), controls 78 ( 4 (61-106). Urine osmolality remained
significantly lower in the lithium patients compared to controls. The
authors interpret their data to suggest that lithium therapy is
followed by an irreversible impairment of urinary concentrating
ability, whereas GFR does not appear to be adversely affected.
Comment: This small study does not have the power to detect
even a 50% reduction in renal function in these patients and the
period of follow-up after withdrawal is too short for any useful
conclusion to be drawn. Other studies support the view that urine
concentrating ability may be permanently impaired after many years of
lithium treatment. The long term effects on GFR remain uncertain.
(C.P. Swainson, M.D., Royal Infirmary of Edinburgh, Scotland)