Trends in utilization and dosing of antipsychotic drugs in Scandinavia: Comparison of 2006 and 2016

Abstract

Aims: The aim of this study was to investigate time trends in dosing and prevalence of antipsychotic prescriptions in Scandinavia.Methods: We retrieved data on antipsychotic use between 2006 and 2016 from Danish, Norwegian and Swedish national prescription registers. For each antipsychotic, we calculated prevalence of use and mean doses, overall and for specific age groups (young, adults and elderly). Results: Antipsychotic use in Scandinavia increased from 16.5 to 17.2 users/1000 inhabitants between 2006 and 2016 (+2.4%, annual change: 0.07 users/1000 inhabitants/year, 95% CI: 0.02-0.20, P = 0.02). In 2006, chlorprothixene and levomepromazine were the most commonly used antipsychotics. By 2016, quetiapine was the most used antipsychotic in all three countries and across all age groups, with an overall 1-year prevalence of 4.05-9.97 users/1000 inhabitants (annual change: 0.57 users/1000 inhabitants/year, 95% CI: 0.54-0.60, P < 0.001). Quetiapine showed a marked decrease in mean doses during the 11-year study period (0.46-0.28 defined daily doses (DDD)/user/day: 39.1%, −0.02 DDD/user/day/year, 95% CI: −0.020 to −0.015, P < 0.001). In 2016, the highest mean doses were seen for clozapine (0.90-1.07 DDD/user/day) and olanzapine (0.66-0.88 DDD/user/day).Conclusions: There is an increased prevalence of antipsychotic prescriptions that coincides with low and/or decreasing mean doses of the majority of commonly used antipsychotics in Scandinavia. Of all antipsychotics, this development was most pronounced for quetiapine. Reasons for and consequences of increased antipsychotic use that lasts shorter periods of time requires further study.

Association of Low-Dose Quetiapine and Diabetes

“…The exclusion of a substantial type 2 diabetes risk with low-dose quetiapine is important, given the increasing number of low-dose quetiapine users worldwide. 3 , 34 Many years of critical attention to the long-term use of benzodiazepines and hypnotics is a possible driver of this increase, and could have created a new public health problem, if low-dose quetiapine were associated with considerable type 2 diabetes risk. However, the high NNH (684) suggests that this risk is likely not important for the individual user or from a public health perspective, as it will not result in a substantial number of new type 2 diabetes cases.…”

“…Other antipsychotic medications commonly used in low doses, such as olanzapine or risperidone, are also associated with metabolic disturbances, 38 and not used off-label to the same extent as quetiapine. 6 , 34 SSRIs are not an ideal comparator because of their association with weight gain 39 and metabolic disturbances. 32 , 40 However, these associations are likely to be inflated from population-based comparisons and not solely represent the potential obesogenic or diabetogenic effect of SSRIs.…”

Predictors of quetiapine extended‐release formulation add‐on in older patients exposed to antidepressant drugs: A Danish register‐based cohort study

“…In fact, efficacy of quetiapine for improving behavioral and psychological symptoms of dementia is not well established and findings from randomized clinical trials are inconclusive 24,25 . Nevertheless, off‐label use of quetiapine and other antipsychotics for dementia has been reported in multiple Scandinavian countries 26 and one study found that 46% of quetiapine‐treated patients with dementia received quetiapine for sleep disorders 27 …”

Use of antipsychotics in Denmark 1997–2018: a nation-wide drug utilisation study with focus on off-label use and associated diagnoses

“…However, a pronounced decrease in the use of benzodiazepine analogues has been observed over the same period ( Danish Health Data Authority ), which might have been replaced, at least partly, by low-dose use of antipsychotics acting as anxiolytics or hypnotics. The quite low average quantities dispensed to each user lends some support to this hypothesis (Højlund et al ., 2019 ).…”

“…Studies addressing the underlying drivers of antipsychotic utilisation are scarce (Olfson et al ., 2012 ; Baandrup and Kruse, 2016 ), and prior studies on overall antipsychotic utilisation commonly lack information on associated diagnoses (Hálfdánarson et al ., 2017 ; Højlund et al ., 2019 ), or were confined to patients with psychiatric diagnoses or contacts (Olfson et al ., 2012 ; Baandrup and Kruse, 2016 ). Thus, these studies did not assess the entire population of users treated in general practice, private psychiatric practice or other medical specialties than psychiatry.…”