Analysis of regional differences in the amount of hypnotic and anxiolytic prescriptions in Japan using nationwide claims data

Abstract

Background In Japan, there has been no investigation of regional differences in the number or amount of prescriptions of anxiolytics or hypnotics. Attributes related to the high amount of prescriptions for these drugs are unknown. We investigated recent trends and regional differences in the amount of prescriptions of hypnotics and anxiolytics in Japan and identified factors associated with these regional differences. Methods The National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB) Open data from 2015 to 2018 were used. We calculated diazepam-equivalent doses (mg) for each drug and the total amount of prescriptions per capita for hypnotics and anxiolytics by sex and age. In addition, we calculated the standardized claim ratio (SCR) of the amount of prescriptions by prefecture. We investigated factors associated with regional differences in the SCRs of hypnotics and anxiolytics using the prefectures’ medical, socioeconomic, and physical characteristics by an ecological study using a linear mixed-effects model. Results The amount of prescriptions of hypnotics and anxiolytics, specifically, the amount of prescriptions of benzodiazepine receptor agonists (BZRAs), decreased in many of the adult age groups from 2015 to 2018. The regression analysis revealed that the number of medical clinics per capita, the number of public assistance recipients per capita, the proportion of persons whose HbA1c ≥ 6.5%, and the proportion of persons whose BMI ≥25 kg/m2 were positively and significantly associated with the SCR of hypnosis. In contrast, the number of public assistance recipients per capita and the proportion of persons whose BMI ≥25 kg/m2 were positively and significantly associated with the SCR of anxiolytics. Conclusions Factors associated with prescription amount of hypnotics and anxiolytics were revealed in this study, and a further study is needed for investigating causal relationships between the prescriptions amount and the associated factors using individual data.

Regional variations in excessive polypharmacy and potentially inappropriate drug use among older adults in Sweden: Trends from 2006 to 2020

“…The indicator “use of three or more psychotropic drugs” displayed the largest variation during the entire period. A high degree of variation between regions with regard to psychiatric polypharmacy have also been found in previous work ( Okui and Park, 2022 ). Among potential explanation are regional prescribing patterns (e.g., opioid-belt in United States and benzo-belt in Sweden) or differences in access to specialist prescribers ( Wastesson et al, 2014 ).…”

Regional difference in multi-psychotropic drug prescription in Japan and its associated factors: an ecological study using national health insurance claims data

“…The age distribution and sex ratio differ between secondary medical areas, and the standardized claim ratio (SCR) was calculated for each area, as performed in previous studies [14,22,31]. The rate of multi-psychotropic drug prescription (Number of prescriptions per population) for each age group and sex in Japan was calculated.…”

“…It was discovered that there were many areas where the SCR was high, especially in Hokkaido, and some areas in Aomori and Akita prefectures were also high. It is known that the prescription amount of hypnotics per capita is high in Hokkaido and that anxiolytics are high in Hokkaido, Aomori, and Akita [14]. Contrarily, it is untrue that all of Hokkaido's regions have high SCRs; regional variations in SCR can also be found within prefectures.…”

“…Additionally, data on medical expenses that are not covered by insurance and uninsured persons' data are not included in the NDB data [21]. Numerous studies have been carried out using the NDB's aggregate data which are publicly accessible as open data [14,22,23].…”

“…Identification of patient traits or geographic areas linked to the multi-psychotropic drug prescriptions is crucial for furthering the improvement of multi-drug prescriptions. Some studies examined regional differences in the frequency of depression consultations or the number of psychotropic medications prescribed in Japan [14,15]. On the other hand, there are no studies that looked into regional differences in multi-drug prescriptions of psychotropic drugs in Japan.…”