Community pharmacist counseling improves adherence and asthma control: a nationwide study

BACKGROUND: Pharmaceutical counseling (PC) interventions have been shown to improve adherence to controller medication and asthma control. However, the real-life impact of these PC interventions in difficult-to-control asthma patients remains unclear. We aimed to assess the effectiveness of PC interventions in real life using nationwide claims data. METHODS: Demographics and drugs use of patients who received ICS in 2017 with or without pharmaceutical counseling were retrieved from a Belgian claims database. Asthma-related drug use from 1 year before first ICS dispensing in 2017 (reference period) was compared with 1 year after. Outcomes were usage of inhaled corticosteroids (ICS) in defined daily doses (DDD), proportion of users of short-acting beta-agonist (SABA), antibiotics, oral corticosteroids (OCS), asthma biologicals and controller-to-total (CTT) ratio. RESULTS: The study population consisted of difficult-to-control asthma patients aged 5–40 years with at least the first interview within 90 days after first ICS dispensing (n = 1350). ICS usage increased significantly in the year after PC intervention compared with the reference period (+ 43.3 DDD/patient, p < 0.05). A nominal decrease was observed in the proportion of SABA (48.0 to 46.2%) and antibiotics (54.5 to 52.7%) after PC intervention compared with the reference period. CTT ratio significantly increased from 0.671 to 0.749 (p < 0.05). The proportion of biological users was nominally lower in the intervention group compared with a control group (n = 50,477) in the post-intervention time period (0.22% versus 0.30%). CONCLUSIONS: This first nationwide study among difficult-to-control asthma patients suggests that community pharmacist counseling is effective in real life to improve controller adherence and asthma control. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12913-022-07518-0.