Long-Term Follow-up Study of Hospitalizations for Acute Coronary Syndrome in Kobe-City and Other Districts Under the Hyogo Smoking Ban Legislation　- A Nationwide Database Study.

Background: Hyogo Prefecture has managed smoking ban legislation with partial restrictions in public places (Hyogo-L) since 2013. Previous studies have reported a significant decrease in admissions for acute coronary syndrome (ACS) in Kobe-city, but not in other districts of Hyogo Prefecture in the 2 years after Hyogo-L. The aim of the present study was to define the long-term effect of Hyogo-L.
Methods and results: The JROAD-DPC dataset was used to collect information on the number of hospitalizations for ACS in Hyogo Prefecture, and in Osaka-city without smoking ban legislation, from April 2013 to March 2020. Poisson regression analysis was performed to calculate incident rate ratios (IRRs) and 95% confidence intervals (CIs). ACS records of 3,101 in Kobe-city, 11,375 in areas of Hyogo Prefecture other than Kobe-city and 11,079 in Osaka-city were collected for admissions. The incidence of ACS reduced significantly over time in Kobe-city [IRR (95% CI); 0.96 (0.94-0.97)], but did not reduce in the others. The decrease in Kobe-city was observed in ACS patients without smoking, hypertension, and hyperlipidemia, but not in those with such risk factors.
Conclusions: The long-term ACS reduction or non-reduction under Hyogo-L was determined at the initial period and the same scenario continued, supporting the importance of legislation and compliance with the smoking ban. The lowering effect was remarkable in ACS patients without risk factors such as non-smoking.