Comparing patient reported and medical record data of adverse drug reactions to anti-seizure drugs.

BACKGROUND

Anti-seizure drugs (ASDs) can potentially cause serious adverse drug reactions (ADRs). Patient self-reporting can increase the rate of ADR detection, but studies examining patient self-reporting of ADRs caused by ASDs are lacking.

AIM: To determine the characteristics of ADRs reported by patients receiving ASDs, assess laboratory data and medical record confirmation of patient-reported ADRs, and explore factors associated with laboratory data and medical record confirmation.

METHOD: A self-reporting questionnaire was distributed to patients prescribed ASDs at outpatient clinics. Patients assessed the causality of suspected ADRs using Causality Assessment Tool. Naranjo's algorithm was used by researchers for causality assessment. Medical records were used to gather information on ADR symptoms, ASD medication, and abnormal laboratory data.

RESULTS

From 478 distributed questionnaires, 93.1% completed the questionnaire and 67.4% of respondents reported at least one ADR. The most common ADRs were drowsiness (50.7%), dizziness (9.7%), and ataxia (4.3%). For causality, suspected ADRs were classified as possible in 52.3% of cases and probable in 46.3% of cases by patients, and possible in 64.7% of cases and probable in 25.7% of cases by researchers. Only 12.7% of patients had laboratory data and/or medical record confirmation of suspected ADRs. The psychiatry clinic was less likely to confirm suspected ADRs compared to the epilepsy clinic (OR = 0.412, p = 0.022).

CONCLUSION

Confirmation of patient-reported ADRs with either laboratory data or medical records was uncommon. Recording patient-reported ADRs in patients' medical history and monitoring laboratory tests related to patient-reported symptoms should be promoted to increase the safety of ASD treatment.