Abstract
Electronic health records (EHRs) are widely used in medication adherence (MA) assessment. Poor adherence in patients with inflammatory bowel diseases (IBD) can lead to worse disease outcomes and increased health costs. This study explores the suitability of southern New Zealand EHRs for estimating adherence, and the relationship between adherence and corticosteroid dispensings (indicating negative disease outcomes).
Medication dispensing EHR data of former Southern District Health Board IBD patients were analysed to estimate 3-year adherence, using daily polypharmacy possession ratio. The correlation with the number of corticosteroid dispensings was investigated.
Of 248/1,290 (19%) consenting patients, only 108/248 (44%) had sufficient data available (46%/54% Crohn's disease/ulcerative colitis; 57% female; 89.8%/0.9% NZ European/Māori; mean 5.1 corticosteroid dispensings). Mean adherence was 83.2% (95% confidence interval [CI] 80.0-86.4; standard deviation [SD]:16.7), with 69% of patients having MA ≥80% (good adherence). Median adherence was 13% higher for males versus females (96% vs 83%; p=0.0001). There was no correlation between adherence and the number of corticosteroid dispensings (Pearson's r=0.11; p>0.05). These findings should be considered with caution as the data were not obtained from all pharmacies and the quantum/nature of missing data is unknown.
The patients' adherence seems high, with no correlation with corticosteroid dispensings demonstrated. Useful EHR data are available but need optimisation for adherence assessments.