Forns J, Pottegard A, Reinders T, Poblador-Plou B, Morros R, Brandt L, Cainzos-Achirica M, Hellfritzsch M, Schink T, Prados-Torres A, Giner-Soriano M, Hallas J, Cortes J, Hagg D, Jacquot E, Deltour N, Perez-Gutthann S, Pladevall M, Reutfors J. Antidepressant use in Denmark, Germany, Spain, and Sweden from 2009 to 2014: incidence and comorbidities of antidepressant initiators. Poster presented at the 35th ICPE International Conference on Pharmacoepidemiology & Therapeutic Risk Management; August 27, 2019. Philadelphia, PA. [abstract] Pharmacoepidemiol Drug Saf. 2019 Aug 20; 28(S2):560. doi: 10.1002/pds.4864

BACKGROUND: Antidepressants are among the most prescribed drugs in Europe. Antidepressant choice is influenced by factors related to the specific antidepressant as well as patient-related factors. No studies have described the use of antidepressants and characteristics of adult users in Europe since 2012.

OBJECTIVES: To describe patterns of use and characteristics of adult users of 10 antidepressants from 2009-2014 in four European countries.

METHODS: The antidepressants were citalopram, escitalopram, fluoxetine, paroxetine, sertraline, duloxetine, venlafaxine, amitriptyline, mirtazapine, and agomelatine. This included different classes of commonly used antidepressants in the participating countries. Agomelatine was selected for regulatory reasons. Adult initiators of each study antidepressant from 2009-2014 were identified in the Danish and the Swedish National Registers, GePaRD (Germany), EpiChron (Aragon, Spain), and SIDIAP (Catalonia, Spain). Cumulative incidence of antidepressant initiation was calculated. Initiators were characterised at the start of treatment episode according to age, sex, and presence of comorbidities. Patterns of use, including use of antidepressants prior and during the current episode, were also assessed.

RESULTS: The study included 4.8 million initiators of antidepressants. Citalopram had the highest cumulative incidence (users per 1,000) in all populations except in Aragon, ranging from 65 in Denmark to 38 in Catalonia. Agomelatine (fewer than 10), and paroxetine had the lowest cumulative incidence. Women (> 60%) comprised the majority of antidepressants initiators.

Mirtazapine was used among older initiators (median age range 54 years in Denmark - 67 years in Aragon) with higher prevalence of comorbidities, and fluoxetine was used among younger and healthier initiators (median age range 38 years in Sweden - 50 years in Aragon). The most prevalent comorbidities among initiators were hypertension, diabetes, hyperlipidaemia, and obesity. The results indicated that citalopram and amitriptyline were the most common first-line treatments, whereas agomelatine and duloxetine were mostly used in the second line.

Agomelatine, venlafaxine, and duloxetine were mostly used in combination therapy.

CONCLUSIONS: This study suggests that citalopram and mirtazapine were the most commonly prescribed antidepressants in the populations studied during 2009-2014. Age, presence of comorbidities, and patterns of use in adult initiators differed between antidepressants.