Antipsychotic drug use in Greenland and Denmark: longitudinal and cross-sectional data

Purpose: The aim of this study was to compare the consumption of antipsychotic drugs in Denmark and Greenland between 2014 and 2019. We also investigated the use of antipsychotic medication for schizophrenic and non-affective psychotic patients in both countries. Methods: This study was performed as a register study using data from the medical register in Denmark and Greenland. A cross-sectional study on the prescription of antipsychotic drugs for psychotic patients (F 20–29) in Greenland in September 2020 was also conducted. Results: The prevalence of antipsychotic drug consumption between 2014 and 2019 was higher in Greenland (average 16.9 DDD/1000/day) compared to Denmark (average 9.3 DDD/1000/day) and the consumption increased in Greenland remarkably. Olanzapine was the most widely used drug in both countries and Clozapine consumption was twice as high in Greenland as in Denmark (1.3 versus 0.6 DDD/1000/day). The mean dose of antipsychotics in schizophrenic and non-affective psychotic patients was higher in Greenland than in Denmark and this difference was greatest among institutional residents. In Greenland, 59% of institutional residents received 2 or 3 DDD/day while only 43% in Denmark received it. Polypharmacy was common in both countries. Conclusion: The total consumption and the main dose of antipsychotics in schizophrenic patients was higher in Greenland than in Denmark. Factors contributing to the differences noted appear to be a combination of age and gender differences among patients in the two countries. Socio-economic differences, and differences in treatment options can contribute to the differences and must be investigated further.