Do patients initiate therapy? Primary non-adherence to statins and antidepressants in Iceland.

BACKGROUND: Primary non-adherence occurs when a drug has been prescribed but the patient fails to have it dispensed at the pharmacy. AIMS: To assess primary non-adherence to statins and antidepressants in Iceland, the association of demographic factors with primary non-adherence, and the time from when a prescription is issued until it is dispensed. METHODS: Data on patients receiving a new prescription for a statin or an antidepressant from the Primary Health Care database were linked with dispensing histories from The Icelandic Prescription Database. The proportion of patients who did not have their prescription dispensed within a year from issuing (primary non-adherent) was assessed, as well as the time from issue until dispensing. Associations between demographic factors and primary non-adherence were estimated using logistic regression. RESULTS: The overall primary non-adherence was 6.3% and 8.0% for statins and antidepressants, respectively. The majority of patients had their prescription dispensed within 7 days (85% for statins, 87% for antidepressants). Being disabled and receiving a prescription for an expensive drug was associated with higher rates of primary non-adherence. CONCLUSION: The rate of primary non-adherence to statins and antidepressants in Iceland is low. Vulnerable groups such as the disabled should be given special attention when new drugs are prescribed.

The association between lifting an administrative restriction on antidepressant dispensing and treatment patterns in Iceland.

PURPOSE: On March 1st 2009, restrictions on the dispensing of selective serotonin reuptake inhibitors (SSRI) in Iceland were lifted. Incident rates and changes in early discontinuation and switching before and after the change were investigated. METHODS: New users of antidepressants between March 1st 2006 and March 1st 2010 were selected from the Icelandic Prescriptions Database. The study population was split into one intervention cohort (2009) and three comparison cohorts (2006, 2007, and 2008). Incidence rate ratios (IRR) and odds ratios (OR) were used to compare incidence rates and early discontinuation. RESULTS: The overall incidence rates of antidepressant use decreased from 33.10 to 28.71 per 1000 persons per year (IRR 0.87; 95% confidence interval (CI), 0.78-0.97) from the 2006 to the 2009 cohort. The incidence rate for SSRIs did not change over the period. Early discontinuation for SSRIs increased from 30.2% in 2006 to 34.1% in 2009 (OR 1.19; 95% CI 1.06-1.33). CONCLUSIONS: The change in reimbursement does not seem to have affected incidence rates but it may be related to increased early discontinuation, which can lead to increased drug wastage. It might be more clinically rational to initiate patients on smaller supply, allowing for more frequent check-up visits.