Characterizing drug-induced stuttering in electronic health records

Drug-induced stuttering is a phenomenon where the onset of stuttered speech is caused by exposure to pharmaceutical chemical substances. This acquired form of stuttering features many of the same overt speech behaviors as developmental stuttering. Investigations of drug-induced stuttering have been limited to adverse drug reaction reports and case studies. This study leveraged electronic health records (EHRs) at a major university medical center to identify drug-induced stuttering within medical notes, followed by classification of implicated drug types.

A previous systematic EHR review of approximately 3 million individuals to identify cases of developmental stuttering resulted in 40 suspected cases of drug-induced stuttering. In the present study, these cases were reviewed comprehensively to evaluate: name, class, and mechanism of action of suspected drug, level of evidence for the implicated drug as a causal agent, therapeutic measures taken, and progression or remission of stuttering.

Eighteen different drugs were linked to possible drug-induced stuttering in 22 individuals. Antiseizure agents, CNS stimulants, and antidepressants were the most common drug classes implicated in drug-induced stuttering. topiramate (Topamax) was the most commonly implicated drug across all records reviewed.

This study represents the first analysis of health system data examining drugs implicated in drug-induced stuttering in a clinical setting. Augmenting previous case reports and database reviews, a variety of drugs were identified; however, improved reporting of drug-associated speech fluency changes within the EHR are needed to further amass evidence for suspected drugs and their associated epidemiological and clinical characteristics.