Long-term lithium treatment and renal functions. A prospective study

Area of Science:

• Nephrology
• Pharmacology
• Psychiatry

Background:

• Lithium is a widely prescribed mood stabilizer.
• Long-term lithium therapy can affect renal function.
• Monitoring kidney health is crucial for patients on lithium.

Purpose of the Study:

• To assess the impact of lithium treatment on renal function.
• To evaluate changes in tubular and glomerular function over 12 months.
• To determine if lithium-induced renal changes progress over time.

Main Methods:

• Studied 53 patients before and at 4 and 12 months of lithium treatment.
• Assessed tubular function using the DDAVP (Minirin) test.
• Measured glomerular filtration rate via creatinine clearance.

Main Results:

• Mean maximum urine osmolality decreased from 800 to 702 mosm/kg H2O at 4 months, then slightly increased to 723 mosm/kg H2O at 12 months.
• Mean creatinine clearance decreased from 128 ml/min to 106 ml/min at 4 months, then increased to 114 ml/min at 12 months.
• Lithium treatment (serum levels ~0.6 mmol/l) initially reduced renal concentrating ability and glomerular filtration rate.

Conclusions:

• Lithium therapy, at therapeutic serum levels, can impair renal concentrating ability and glomerular filtration rate in the early treatment phase.
• The observed decrease in renal function does not appear to worsen during the first year of lithium treatment.
• Regular monitoring of renal function is recommended for patients undergoing long-term lithium therapy.