2017. Age-specific Distribution of Antimicrobial Days of Therapy (DOT) Using National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB Japan): Comparison with Defined Daily Doses per 1,000 Inhabitants Per Day (DID)

BACKGROUND: Nationwide surveillance of antimicrobial use (AMU) is often assessed by defined daily doses per 1,000 inhabitants per day (DID) as a measurement unit. We previously reported the age-specific distribution of AMU using National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB Japan), which archives e-claim big data (Infection. 2018 46:207–214). The estimated AMU assessed by DID could be underestimated in patients with diminished renal function and in pediatric patients. Our objective was to analyze days of therapy (DOT) using NDB and to evaluate its utility by comparing with DID. METHODS: The DID value was calculated by the same method in our previous study.The DOT values was extracted from data in NDB and were standardized by a population and were described as per 1,000 inhabitant days (DOTID). The values of DID, DOTID and the ratios (DID/ DOTID), the indicator for reflecting the extent of daily dosage were compared between three groups stratified by age groups (younger than 15 years: children, 15–64 years old: productive age, and older than 64 years: elderly). RESULTS: The total DID (oral, parenteral) from 2013 to 2016 in three age groups was shown in the following table. The total DID (oral, parenteral) in three age groups in 2016 were 16.31, 0.27 in the children, 12.82, 0.39 in productive age, and 15.91, 2.13 in elderly, respectively. Similarly, the total DOTID (oral, parenteral) in three age groups in 2016 were 36.15, 1.20 in the children, 16.48, 0.80 in productive age, and 23.52, 3.62 in elderly, respectively. The total DID/DOTID (oral, parenteral) in three age groups in 2016 were 0.45, 0.23 in the children, 0.78, 0.49 in productive age, and 0.68, 0.59 in elderly, respectively. The gap between DID and DOTID in children was much larger than that of other age groups regardless of dosage form, suggesting that AMU assessed by DID could be underestimated, especially in children.The gap between DID and DOTID in elderly was comparable with that in productive age, suggesting that daily dosage in the elderly is similar to that in productive age. CONCLUSION: These results demonstrated the utility of AMU surveillance using the DOTID as a tool and benchmark to assess the AMU, especially in children, and the ratio of DID to DOTID could be useful as an indicator for reflecting the extent of daily dosage. [Image: see text] DISCLOSURES: All authors: No reported disclosures.