Langdurig gebruik van antidepressiva in Nederland in 1991-2001: prevalentie, incidentie en risico-indicatoren

To determine the prevalence, incidence and average duration of use of selective serotonin-reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs) in the Netherlands in 1992-2001, as well as the incidence of prolonged SSRI use and the possible determinants thereof in the years 1991-1997.

Design

Descriptive.

Method

On the basis of pharmacy data in the PHARMO-database on approximately 850,000 patients, a calculation of the prevalence (number of users of an antidepressant per 1000 persons on an arbitrary day) and the incidence (number of new users per 1000 persons per year) was made for each year. Prolonged use was defined as the uninterrupted use of an antidepressant during at least 12 months. The relative risk for prolonged use was calculated and corrected for possible determinants with the aid of Poisson and Cox regression analysis.

Results

Both the prevalence (2.2 to 17.1 per 1000 persons) and the incidence (3.7 to 14.5 per 1000 persons per year) of the use of SSRIs increased in the period 1992-2001 while the use of TCAs remained stable. An increasing number of the 9857 SSRI-users who were included in the follow-up study became long-term users (n = 2909) during the treatment (a total of 30). Female gender, advanced age, prior use of benzodiazepines and treatment by a psychiatrist were associated with an increased risk of becoming a long-term user.

Conclusion

Both the prevalence and the incidence of the use of SSRIs increased during the 1990s. This can be explained by both the larger number of patients starting on an antidepressant and the longer continuation of the treatment. During the follow-up period, 30 of the patients became a long-term user at one time or another.

Ned Tijdschr Geneeskd 2005;149:708-11