Longitudinal Symptom Burden and Pharmacologic Management of Catatonia in Autism With Intellectual Disability: An Observational Study.

Catatonia is a highly morbid psychomotor and affective disorder, which can affect autistic individuals with and without intellectual disability. Catatonic symptoms are treatable with pharmacotherapy and electroconvulsive therapy, but the longitudinal effectiveness of these treatments in autistic individuals has not been described. We conducted a prospective observational cohort study of patients with autism and co-morbid catatonia who received outpatient care in a specialized outpatient clinic from July 1, 2021 to May 31, 2024. Data investigating pharmacologic interventions, and clinical measures including the Bush Francis Catatonia Rating Scale (BFCRS), Kanner Catatonia Severity Scale (KCS), Kanner Catatonia Examination (KCE), and Clinical Global Impression-Improvement (CGI-I) were collected. Forty-five autistic patients with co-morbid catatonia were treated during the study period. The mean age was 15.6 (SD = 7.9) years [Mdn = 16.0, range 6.0-31.0]. Forty-one patients (91.1%) met criteria for autism with co-occurring intellectual disability. All patients received pharmacotherapy. Forty-four (97.8%) were treated with benzodiazepines with a mean maximal daily dose of 17.4 mg (SD = 15.8) lorazepam equivalents. Thirty-five patients (77.8%) required more than one medication class for treatment. Sixteen (35.6%) patients received electroconvulsive therapy. Fourteen patients (31.1%) attempted to taper off benzodiazepines after achieving clinical improvement during the study period; of these, 5 patients (11.1%) were successfully tapered off, and the remaining 9 (17.8%) discontinued the taper due to a return of catatonic symptoms. Statistically significant improvement was observed across all clinical domains except the KCS. However, the majority remained at least partially symptomatic over the study period. Three patients (6.7%) died over the study period. Despite clinical improvements while receiving the gold standard for psychopharmacologic management of catatonia, chronic symptoms remained for the majority of catatonia patients over the study period, and few were able to taper and discontinue benzodiazepine treatment. Notably, the open label design of this study is a limiting factor when interpreting the results.