Half of BD diagnoses inconsistent long-term
MedWire News: Study findings show that even with optimal assessment practices, the long-term diagnostic consistency of bipolar disorder (BD) is highly variable due to the presence of complex clinical presentations.
Camilo Ruggero (University of North Texas, Denton, USA) and co-authors say their study “represents one the first studies to examine multiple factors, particularly childhood factors, that could help explain the lack of consistency in the bipolar diagnosis across time.”
For the study, the team looked at 195 first-admission patients with psychosis who were assessed after hospitalization and at 6 months, 2 years, and 10 years. Patients were diagnosed with BD on at least one of the assessments using optimal assessment practices, and diagnoses were blind to all previous consensus diagnoses.
The researchers found that of the 195 patients diagnosed with BD at some point, 98 (50.3%) were consistently diagnosed with the disorder at every available assessment. The remaining 97 (49.7%) patients were inconsistently diagnosed, having been given a nonbipolar diagnosis at least once in the 10-year period.
Of the 108 patients who were diagnosed with BD at baseline and re-assessed at 10 years, 86 (79.6%) had a consistent BD diagnosis throughout follow-up.
Among the 97 inconsistently diagnosed patients, the most common non-BD diagnosis was a schizophrenia spectrum disorder (52.4% schizoaffective disorder, 38.1% schizophrenia, and 9.5% schizophreniform diagnoses).
Comparing patients who were consistently diagnosed with those whose diagnosis shifted over the 10-year period, Ruggero and colleagues identified the presence of childhood psychopathology (in 66.3% vs 84.4%, respectively) and poorer illness course (as defined by more serious overall symptoms and functioning) as variables associated with an increased risk for change in diagnosis.
Conversely, patients who were consistently diagnosed were more likely to have been given a BD diagnosis at discharge from the hospital after initial admission (68.4% vs 40.7% of patients), and to have initially experienced a manic, rather than mixed or depressed, episode (80.6% vs 66.0% of patients) compared with those who were inconsistently diagnosed.
No differences were found between the groups with respect to rates of mixed episodes, comorbidity of anxiety or substance use disorders, type or intensity of treatment exposure, or family psychiatric history.
“These findings highlight the need for early diagnosis among patients originally presenting with psychosis to be conceptualized as provisional until the course of the disorder makes the diagnosis clearer,” write the authors in the journal Bipolar Disorders.
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By Ingrid Grasmo