Nurse-Provided Medication Guidance for Improving Drug Adherence to Thiopurines in Outpatients With Inflammatory Bowel Disease: A Single-Center Prospective Study

Background and Aims Drug adherence is critically important for patients on thiopurines. We examined whether nurse-provided medication guidance improves drug adherence to thiopurines and clinical activity in patients with inflammatory bowel disease (IBD). Methods IBD outpatients taking a stable dose of thiopurines for 1 year were enrolled. After a baseline survey including the Morisky Medication Adherence Scale (MMAS)-8, nurses provided medication guidance to each patient using a specialized leaflet. The same survey was conducted 2 and 6 months after the guidance. Results Among 110 enrolled patients, 74 met the analysis criteria. In the low adherence group (MMAS-8 <6), the median MMAS-8 score significantly increased from 4 (range 1-5.75) to 5.25 (2-7) at 2 months (P = .0135) to 5.625 (2.5-7.75) at 6 months (P = .0004), but not in overall or the high adherence group (MMAS-8 >= 6). Older age (>= 43 years, odds ratio [OR] = 5.63, 95% confidence interval [CI]: 1.59-19.9, P = .0074) and shorter disease duration (<129 months, OR = 6.78, 95% CI: 1.77-26.0, P = .0052) were independently associated with high adherence. Although clinical activity scores did not change during the observation period, the overall mean corpuscular volume (MCV) level significantly increased from 92.3 fL (61.4-105.5) to 92.5 (73.7-107.8) at 2 months (P = .0288) and 93.9 (74.4-107.6) at 6 months (P = .0062). MCV levels significantly increased in the low adherence group at 6 months (92.2 [72.2-105.5] to 94.0 [74.4-107.6], P = .0392) and tended to increase in the high adherence group (92.3 [61.4-101.2] to 93.6 [74.9-99.7], P = .0651). Conclusions Nurse-provided medication guidance improved drug adherence to thiopurines in IBD patients with low adherence and can also benefit those with high adherence. Lay Summary Nurse-provided medication guidance using a leaflet prepared by a multidisciplinary team significantly improved drug adherence to thiopurines in patients with inflammatory bowel disease with low baseline adherence and can also benefit those with high adherence.