High prevalence of hypokalemia in acute psychiatric inpatients.
BACKGROUND
Hypokalemia is an easily identifiable, clinically important but commonly neglected condition in psychiatric patients. This study intended to examine the prevalence of hypokalemia and its clinical correlates in acute psychiatric inpatients.


METHODS
This retrospective study was conducted over a 6 month period in 2008. The case notes, computerized records and laboratory results of all patients who were consecutively admitted to the acute psychiatric wards in a University-affiliated regional psychiatric unit were studied.


RESULTS
Three hundred forty-seven patients out of 440 admissions were studied. Hypokalemia, as defined by serum potassium level of less than 3.5 mmol/L, was found in 20.5% of patients with a higher prevalence in psychotic patients (27.7%). The mean potassium level of psychotic patients was lower than that of the overall study population (3.72 vs. 3.81 mmol/L, P<.05). White cell counts among the hypokalemic patients were higher than those without hypokalemia (7.8 vs. 7.1 x 10(9)/L, P=.02).


CONCLUSIONS
Hypokalemia was common among acute psychiatric inpatients. Both agitation and the use of antipsychotics were postulated to contribute to the high prevalence of hypokalemia among acutely ill psychiatric patients.
Lam
Marco Ho-bun
MH
Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Chau
Steven Wai-ho
SW
Wing
Yun-kwok
YK
D000208:Acute Disease; D000328:Adult; D015992:Body Mass Index; D003404:Creatinine / Q000097:blood; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007008:Hypokalemia / Q000453:epidemiology*; D007677:Kidney Function Tests; D008297:Male; D015995:Prevalence; D011618:Psychotic Disorders / Q000453:epidemiology* / Q000534:rehabilitation*; D012189:Retrospective Studies
D003404:Creatinine