Evaluation of Patient's Knowledge of Atorvastatin Information in Patient Information Leaflets: A Pre- Post Intervention Study in Thailand

Purpose: This study aimed to evaluate the effect of using atorvastatin PIL on patients' medication knowledge, perceptions of the PIL usefulness, their anxiety about the medication, and factors related to these aspects. Patients and Methods: A pre-post intervention study was conducted in outpatients at a university hospital. Patients prescribed atorvastatin were enrolled using systematic random sampling. Participants were asked to complete Self-Administered Questionnaire to assess atorvastatin knowledge at baseline. An atorvastatin-PIL produced by the manufacturer was introduced to the participants as the intervention. One month after receiving the PIL, the participants were re-assessed. Ten questions were developed to assess atorvastatin knowledge and visual analog scale (VAS) was used to assess perceived benefits of using the PIL and patient anxiety about the medication. Multiple linear regression was used to assess the related factors. Results: Of 450 questionnaires distributed, 370 were returned. Atorvastatin knowledge significantly increased with mean score of 5.06 +/- 1.92 at baseline to 8.34 +/- 1.79 at 1-month after intervention. Reading all sections of the PIL (p=0.017) and working for civil service (p=0.006) were associated with higher knowledge scores at baseline and after intervention. Low educational level was associated with lower knowledge scores at baseline (p=0.002), but experience of allergy (p=0.042) was associated with higher knowledge scores after the intervention. Patients had high level of perceived usefulness from the PIL (average scores=8.87 +/- 1.83) and low level of anxiety (average scores=3.69 +/- 3.06). Reading all sections of the PIL (p=0.007) and taking more than 5 medications (p=0.012) were related to perceived usefulness of the PIL. Females (p<0.001) and herbal supplement users (p=0.048) were related to anxiety about the medication. Conclusion: PILs could improve medication knowledge in patients. Patients' perceptions of benefits of PILs were high and anxiety about medication was low. Use of PILs should be encouraged to improve patients' knowledge and appropriate use of medications.