麻豆传媒

SAN DIEGO -- The hypertension and anxiety treatment propranolol improved general social functioning in young adults with autism spectrum disorder, a small double-blinded, counterbalanced, placebo-controlled study showed.

Participants who received propranolol had significantly improved General Social Outcomes Measure scores compared with those who received placebo (P=0.02), according to David Beversdorf, MD, of the University of Missouri in Columbia, and colleagues reported at the American Academy of Neurology meeting here.

Noradrenergic antagonists such as propranolol "are known to benefit performance on language tasks believed to be due to effects on signal-to-noise," Beversdorf noted during an oral presentation of the results, adding that the benefits are seen in difficult tasks, with stressors, and in language among patients with autism spectrum disorder.

He noted that a number of studies have suggested a benefit in autism from a wide range of drugs, from oxytocin for social behavior, to Alzheimer's disease drugs like NMDA antagonists and GABA agonists, to language and social benefits from propranolol.

He also noted that "most drug management is symptomatic," and can trigger symptoms of anxiety, aggression, and obsessiveness.

To test the effects of propranolol on social functioning in autism spectrum disorder, a population of 11 young adult men with a mean age of 19.39 and a mean 12.5 years of education were tested twice in a counterbalanced order.

Participants given propranolol received a 40 mg dose -- which Beversdorf explained was the most effective dose in a population of healthy controls -- and were switched to placebo on follow-up testing, and vice versa.

Following treatment, the young men completed a general social outcome measure task which involved a researcher asking open-ended questions on the participant's choice of one of two topics.

Participants were scored on a three-point scale for how well they stayed on topic, how frequently they shared new information, how much they reciprocated in dialog, how well they were able to transition between speaker and listener roles, use of nonverbal communication, and appropriate use of eye contact.

Beversdorf noted that there is a "lack of central coherence in autism" that includes imaging models showing local hyperconnectivity and global underconnectivity, impairment in tasks that involve semantic network flexibility, and extensions to the social domain.

For follow-up studies, he said he would like to test a larger sample size, a sample that included female participants, and varying propranolol doses.

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