Increased energy or motor activity is a more important symptom for diagnosing mania within bipolar disorder than are mood changes, a study of 117 hospitalized patients suggests.
Increased energy/activity has been proposed as a core symptom of manic episode in DSM-5. "The present results support the hypothesis that increased energy or activity ... represents the core feature of the manic syndrome," wrote Dr. Elie Cheniaux of the State University of Rio de Janeiro and his colleagues (J. Affect. Disord. 2014;152-4:256-61).
The investigators evaluated the symptoms of each patient hospitalized with an acute manic episode using several instruments. All of the patients took the Mini International Neuropsychiatric Interview, a tool that allows psychiatric diagnoses to be formulated based on DSM-IV and ICD-10 criteria. Those who met the DSM-IV criteria for a manic episode were administered the 37-item Schedule for Affective Disorders and Schizophrenia (SADS)–Change Version, a scale that evaluates the presence of manic, depressive, anxiety, and psychotic symptoms. Dr. Cheniaux and his colleagues performed a Confirmatory Factor Analysis to determine which items best fit the mania dimension. Additional tools such as an Item Response Theory (IRT) Analysis were used to determine the extent to which each symptom described different levels of severity.
Most of the patients (58.1%) were female, the average age was 42.4 years, and the average age at first crisis was 24.3 years. Mania proved to be more frequent than depression in the first crisis (P less than 0.001).
The IRT analysis assigned values to each symptom, and the highest values were assigned to "increased energy" (4.05), "elated mood" (2.54), "less need for sleep" (2.07), and "increased activity" (1.98). The item "anger" got the lowest value (1.02) and "differentiates patients with mania relatively little, with similar levels across severity levels," they wrote.
Dr. Cheniaux said in an interview that he had expected a higher factorial loading with anger. "It is possible that the angriest patients refused to participate in the study, so the symptom of anger could be underrepresented in our study," he said.
Ultimately, the investigators found that patients’ increased energy was the alteration that correlated "the most with the total severity of manic symptoms."
They cited several limitations of the study. For example, patients in the sample might not be representative of bipolar patients in the general population because they were evaluated while their manic symptoms were at their peak. In addition, the investigators suggested only six manic symptoms: increased activity, less need for sleep, increased energy, elated mood, increased self-esteem, and anger. Still, the results suggest that changes in the DSM-5 in the diagnostic criteria for a bipolar diagnosis could be more extensive, they wrote.
Dr. Cheniaux reported that he had no conflicts of interest.