[Antidepressant and antipsychotic drug prescribing in Lombardy].

Background: The patterns of antidepressant and antipsychotic drug prescribing have rarely been studied in large and geographically defined catchment areas. In the present study we examined the prevalence and distribution of antidepressant and antipsychotic prescribing in Lombardy, a northern Italy region of nine million inhabitants.

Methods: This study used the Regional Administrative Database of Lombardy. This database includes all prescriptions reimbursed by the National Health System in the population living in this region. All antidepressant and antipsychotic prescriptions dispensed from the 1st January to the 31st December 2001 were extracted and prevalence data calculated by dividing antidepressant and antipsychotic users by the total number of male and female residents in each age group. In addition, from the Regional database of hospital admissions we extracted all patients aged 65 or above with cerebrovascular-related outcomes for the year 2002. The two databases were linked anonymously with the aim of investigating the relationship between exposure to psychotropics and occurrence of cerebrovascular accidents in the elderly.

Results: During the study period 404,238 individuals were dispensed antidepressants, yielding a prevalence of use of 2.85 (95% CI 2.84, 2.87) per 100 males and 5.92 (95% CI 5.90, 5.94) per 100 females. The prevalence of use progressively rose with age in both sexes, with the highest rates in old and very old individuals. The majority of individuals received a pharmacological treatment with selective-serotonin reuptake inhibitors only, slightly more than 12% received a treatment with tricyclic antidepressants. A total of 86,187 subjects were dispensed antipsychotic agents, yielding a prevalence of use of 0.87 (95% CI 0.86, 0.88) per 100 males and 1.01 (95% CI 1.00, 1.02) per 100 females. The prevalence of use progressively rose with age in both sexes, with the highest rates in old and very old subjects. Concerning the relationship between exposure to second-generation antipsychotics (SGAs) and occurrence of cerebrovascular (CBV) accidents, the analysis showed a significantly increased risk of CBV events in elderly subjects exposed to SGAs in comparison with those exposed to first-generation antipsychotics (FGAs) (3,31%, 95% CI 2,95-3,69 vs. 2,37%, 95% CI 2,19-2,57). Finally the analysis indicated no differences in the proportion of cerebrovascular events in elderly subjects exposed to TCAs and SSRIs.

Conclusions: The very high rates of antidepressant and antipsychotic drug prescribing detected in late life suggest the need of characterising these individuals in terms of medical and psychiatric characteristics, needs and quality of life. It also suggests the need for pragmatic clinical trials, carried out in the general practice, with the aim of assessing whether antidepressants are effective in these conditions. The data provide preliminary epidemiological evidence that exposure to SGAs, in comparison with exposure to FGAs, significantly increased the risk of cerebrovascular accidents in the elderly.