Depression is a burning issue in our society. Studies estimate the prevalence to be about 12 %, which seems to be even higher in Slovenia (about 15 %). Antidepressants (AD) are primarily used to treat depression. In the last 10 years, new active ingredients have entered the market and guidelines for the treatment of depression have been renewed. The aim of our study was to analyze the patterns of outpatient antidepressant prescribing between 2009 and 2018 and the persistence of patients in therapy. For the study, we used an anonymized database of prescription drugs from which we selected antidepressants (anatomical-therapeutic-chemical (ATC) code N06A) and processed them using the SPSS program.
In 2018, a total of 567,713 prescriptions for AD were dispensed: Prescriptions AD from the selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRI) pharmacological groups predominated, with escitalopram being the most commonly prescribed. At least one prescription for AD was received by 147,307 individuals in 2018; the prevalence of AD recipients was 7 %. The number of recipients increased with age. The average age of recipients was about 60 years, and among those over 80 years of age, 1 in 5 received AD.
AD use has increased over the past 10 years. The number of prescriptions for AD increased by 30 % and the number of defined daily doses (DDDs) prescribed by 40 %. Escitalopram and sertraline dominated among the agents over the years. Prescriptions for duloxetine and mirtazapine are on the rise, and pharmacogroups such as tricyclic antidepressants (TCA) and norepinephrine-dopamine reuptake inhibitors (NDRI) are on the decline. The number of recipients of AD has increased by 20 % in 10 years. When standardized to 2009 age distribution, the increase was about 7 %, implying that much of the increase is due to an aging population. Throughout the period, female recipients predominated (70 %), and analysis by age groups showed the largest increase in the number of recipients among the oldest.
A large proportion (apromately one third) of AD recipients discontinued treatment within the first 30 days or received only 1 prescription for AD. Among those who received at least 2 prescriptions or were treated for at least 30 days, as many as 40% discontinued treatment within the first 6 months. The mean persistence time in this group was 16.7 months. In total, 2/3 of the recipients discontinued therapy within the first 6 months, which is quite worrying, as the guidelines recommend a minimum treatment period of at least 6 months. Most people who persist AD stay on monotherapy. Older recipients show better persistence. We found significant differences in treatment persistence with respect to the first agent prescribed (the highest likelihood of stopping mirtazapine) or pharmacological group, with the SSRI and SNRI groups showing the best persistence.
In the study, we found that the number of recipients of AD increases with age, especially in the elderly. SSRIs remain among the most commonly prescribed ADs. Persistence of therapy is not in line with treatment guidelines, with only 40 % of individuals persisting on treatment for more than 6 months.
|