Prolonged QT interval in acute psychotic patients

Some recent clinical studies indicate that hypokalemia is characteristic fo r acute psychotic patients at the time of emergency admission. As hypokalem ia is one of the major causes for prolonged QT interval, it was hypothesize d that acute psychotic patients could show prolonged QT interval. Sixty-sev en drug-free, acute psychotic patients were evaluated for corrected QT (QTc ) interval, as well as demographic and clinical characteristics at the time of emergency admission. The mean QTc interval of psychiatric emergency pat ients was prolonged, and the mean QTc interval of psychiatric emergency pat ients was longer than that of psychiatric outpatients (t = 5.20, P < 0.0001 ). Age- or gender-related difference, circadian fluctuation of QT interval, medication, concomitant disease, obesity, and serum electrolytes except po tassium were not major causes. There was a significant negative correlation as evidenced by a coefficient of correlation of -0.28 (P < 0.05). As psych iatric emergency patients often receive parenteral antipsychotics, which ma y have adverse effects on prolonged QT interval, paying attention to QT int erval might have some clinical significance on emergency admission. (C) 200 0 Elsevier Science Ireland Ltd. All rights reserved.