Impact of pharmacy services on cystic fibrosis medication adherence: Update

We are writing this letter to provide an update of the continuing impact and sustainability of the integrated pharmacy team model and a dedicated cystic fibrosis (CF) clinic pharmacist onmedication adherence andhospitalizations to thearticle “Impact of pharmacy servicesoncystic fibrosis medication adherence” by Zobell and colleagues. The original retrospective analysis utilized information fromhealth insurance claims and patient medical charts from January 1, 2014 to December 31, 2016. This follow-up study extended the date range of analysis to December 31, 2017. These data were analyzed using the same fashion that was described in the original article. With the inclusion criteria of continuous health insurance enrollment, some patients were excluded leading to a total of 48 patients in the updated analysis. The 2017 total mean dornase alfa yearly medication possession ratio (MPR) of 0.84 was slightly decreased from the 2016 MPR reported in the article, but it still considered to be high adherence since it is greater than or equal to 80%. In the generalized estimating equations analyses (GEE) for adherence on the updated data, patients followed by the integrated pharmacy team model continued to show increased the likelihood of monthly dornase alfa adherence (P < 0.001, OR = 2.25) compared to months when patients were not followed by the integrated pharmacy team. Also, having the dedicated CF clinic pharmacist seeing patients in clinic continued to show increased likelihood of monthly dornase alfa adherence (P < 0.001, OR = 1.86) compared to months when not seen by the dedicated CF clinic pharmacist. In theGEE for hospitalizations, the odds ofmonthly hospitalization were not significantly reduced when patients were followed by the integrated pharmacy team model (P = 0.113, OR = 0.67) or the dedicated CF clinic pharmacist (P = 0.135, OR = 1.46), which were similar to the findings described in the original article. With these results continuing to be non-significant, another GEE for hospitalizations was performed analyzing the effect of adherence on the odds of monthly hospitalization since we have shown that pharmacy services have been able to significantly improve the likelihood of monthly dornase alfa adherence. The monthly odds of hospitalization were significantly reduced when patients were adherent to dornase alfa (P < 0.001, OR = 0.418) as compared to when patients were not adherent. A Pearson correlation analysis was also performed on the relationship between adherence and hospitalizations. This analysis found a significant negative relationship between dornase alfa adherence and hospitalizations from 2014 to 2017 (P = 0.018, Pearson correlation coefficient = −0.37), suggesting that as adherence increases, hospitalizations decrease (see Figure 1). With the additional year of data, we were able to show the sustainability and benefit of pharmacy services at our CF center through maintenance in the improvements in adherence by both the integrated pharmacy team model, and the designated CF clinic pharmacist alone, as well as the significant reduction in the monthly odds of hospitalization in patients adherent to dornase alfa. This