SUN-226 PRESCRIPTION VARIATION OF DRUGS FOR CHRONIC KIDNEY DISEASE AMONG PREFECTURES IN JAPAN

Abstract

In Japan, the entire population is covered by the public social health insurance system and healthcare services are provided at uniform prices throughout the country. Ninety-five percent of nationwide health insurance claim information is covered by National Database of Health Insurance Claims and Specific Heath Checkup of Japan (NDB), which was released and became openly accessible in 2016 but still has not been well analyzed in terms of kidney disease practice. . This current study was performed to reveal the regional variation of chronic kidney disease (CKD) medication in Japan through this big data combined with other type of geography-based clinical database. Data of total claimed amounts of phosphate binders and erythropoiesis-stimulating agents (ESA) were obtained from 2nd NDB Open Data Japan 2015. Pearson correlation coefficients were calculated among prescription amount of these drugs per CKD patients and several social, medical factors of each prefecture. Multiple regression analysis was performed using possible factors affecting phosphate binders or ESA prescription per CKD patients. Total claimed amount was 585,485,115 for phosphate binders and 2,373,777 for ESA. Variations of prescription amounts per CKD patients among prefectures were 4.9 folds for phosphate binders and 6.1 folds for ESA. Prescription amount of phosphate binders was negatively correlated with the number of hospital bed per population (r=-0.29, p<0.05), whereas positive correlations were observed between the number of pharmacies per habitable area (r=0.31, p<0.05), population density (r=0.33, p<0.05), total family income (r=0.29, p<0.05), number of certified nephrologists per CKD patients (r=0.40, p<0.05) and ratio of certified nephrologists over medical doctors (r=0.34, p<0.05). Correlation between ESA and the factors showed similar trends as phosphate binders, though only the number of nephrologists per CKD patients (r=0.39, p<0.05) and the ratio of nephrologists over medical doctors (r=0.33, p<0.05) were statistically significant. Multiple regression analysis revealed that only the number of certified nephrologists per CKD patients was associated with ESA prescription per CKD patients. The present study revealed the variations in prescriptions of CKD-related drugs among prefectures in Japan even under uniform healthcare system. Phosphate binders and ESA prescription were correlated with certified nephrologists per CKD patients. As for ESA prescription, the number of certified nephrologists per CKD patients were associated with more usage of the agents. Although control levels of CKD-mineral and bone disorder (MBD) and renal anemia of each prefecture were not available, these results indicate the possibility of appropriate distribution of nephrologists lead to the sufficient prescription of CKD-related drugs.