Renal, thyroid and parathyroid function during lithium treatment: laboratory tests in 207 people treated for 1-30 years.

A total of 207 patients (diagnoses revised according to DSM-HI-R) attended our outpatient clinic and were treated with lithium for 1–30 years. They were subjected to conventional renal, thyroid and parathyroid function tests. With increasing treatment duration, the renal tests showed only moderate deviations from expected reference values. No patient developed renal insufficiency. Oversubstitution (thyrotropin ≤0.1 mU/l) was suspected in 25% of the patients on thyroxine. Cross-sectionally unrecognized hypothyroidism was found in 6% of the patients. Elevated ionized serum calcium was found in 25% and elevated serum intact parathyroid hormone in 23% of the patients.