Effects of Divalproex Versus Lithium on Length of Hospital Stay Among Patients With Bipolar Disorder

The medical records of all inpatients with bipolar disorder at the Connecticut Mental Health Center in 1997 were examined to compare length of stay for patients who began monotherapy with divalproex (27 treatment starts) and lithium (20 treatment starts). No statistically significant difference was found in length of stay (11.5±6.9 and 10.3±5.2 days for patients on divalproex and lithium, respectively) or other length-of-stay variables. Demographic variables, diagnostic variables, and dosages of neuroleptics and benzodiazepines used adjunctively were similar as well. Dosages and blood levels for divalproex and lithium were consistent with practice guidelines. Prospective randomized studies are needed to compare the cost-effectiveness of divalproex and of lithium in the treatment of bipolar disorder.