Testing new diagnostic criteria for hypomania.

BACKGROUND: A recent series of studies has questioned DSM-IV diagnostic criteria for hypomania, suggesting that overactivity (increased goal-directed activity) should have priority over mood change as stem criterion. Angst has suggested new criteria for hypomania, giving priority to overactivity. Study aim was to test the validity of Angst's diagnostic criteria for hypomania.

METHODS: A consecutive sample of remitted 213 DSM-IV bipolar-II disorder (BP-II) and major depressive disorder (MDD) outpatients were re-diagnosed, during a follow-up visit, by the Structured Clinical Interview for DSM-IV (yes/no structured questions on hypomanic symptoms, skip-out instruction of stem question on mood change not followed, in order to assess all past hypomanic symptoms), by a mood disorder specialist psychiatrist in a private practice. Angst's stem diagnostic criteria for hypomania were tested versus DSM-IV hypomania: 1) overactivity plus at least 3 of the 7 DSM-IV hypomanic symptoms 2) overactivity plus at least 2 of the 7 DSM-IV hypomanic symptoms.

RESULTS: DSM-IV criteria for hypomania were met by 137 patients, overactivity plus 2/7 was met by 146 patients, and overactivity plus 3/7 was met by 135 patients. Of the patients with overactivity plus 2/7, 83.5% also met DSM-IV criteria for hypomania, and of the patients with overactivity plus 3/7 86.6% also met DSM-IV criteria for hypomania. Logistic regression of DSM-IV hypomania versus overactivity plus 2/7 found odds ratio (OR) = 17.6, and versus overactivity plus 3/7 found OR = 18.8. Comparisons between DSM-IV hypomania and Angst's criteria for hypomania showed that there were no significant differences on age, gender, symptom structure of hypomania, number of episodes, episodes duration, and episodes level of functioning. Associations (ORs) between the stem criterion of each definition of hypomania and hypomanic symptoms were often strong. DSM-IV hypomania stem criterion was closely associated with overactivity (OR = 15.4), and Angst's hypomania stem criteria were closely associated with mood change (OR = 7.6 for overactivity plus 2/7, OR = 14.3 for overactivity plus 3/7).

CONCLUSIONS: Results support Angst's criteria for hypomania based on overactivity (overactivity plus 3/7 seems more supported). These criteria do not seem to lead to overdiagnosing hypomania. Previous studies supported the upgrading of overactivity among DSM-IV hypomanic symptoms. Angst's diagnostic criteria may positively impact the treatment of depression. It has been shown that focusing the probing for history of hypomania more on overactivity than on mood change reduces the false-negative BP-II. By using Angst' criteria for hypomania, clinicians may reduce the current high misdiagnosis of BP-II as MDD and the related mistreatment.