[Effect of long-term treatment with neuroleptics or lithium salts on carbohydrate metabolism]

Long-term treatments with neuroleptic drugs or lithium salts are well established and, with regard to side-effects, possess a common denominator: both treatments may increase the body weight, and may influence in different, even contrary ways the carbohydrate metabolism. In this study the oral glucose tolerance test (oGTT) including the determination of immunologically measurable insulin (IMI) has been performed in 49 lithium-treated out-patients, and in 125 inpatients under neuroleptic long-term treatment. The test was repeated within six months in the lithium-group. 3 different evaluation criteria were used. Among the patients with neuroleptic treatment there were 25 to 36% with a pathological glucose tolerance curve; the expected frequency would have been approx. 8%. 55% of the patients had overweight, which positively correlated to the occurrence of pathological glucose tolerance. 24.5 to 30.6% of cases with pathological oGT were found in the lithium-group. 69% of the patients had overweight; age and overweight positively correlated with pathological oGT. According to the very conservative criterion of the European Study Group (EDESG), the still increased frequency of pathological oGT curves in the second investigation, compared to epidemiological data, just failed statistical significance. The results suggest that also under long-term lithium treatment an increased lability of carbohydrate metabolism, be it due to the drug or the manic-depressive disease, must be discussed as a potential risk for the patient.