Age-adjusted death rate from and incidence of stroke and myocardial infarction over 24 years in O City, Ehime Prefecture, Japan: an observational cohort study.

Objective: To elucidate the trends in stroke and myocardial infarction (MI) over 24 years in O City, Ehime Prefecture, Japan.

Materials and methods: We conducted an annual survey of hospital-based disease registrations to determine the incidence and type of stroke (hemorrhagic stroke (HS) and ischemic stroke (IS)) and MI from 1996 to 2022. The numbers of deaths due to stroke and MI were determined using the electronic death certificate dataset provided by the Ministry of Health, Labour and Welfare. The number of deaths and incidences of stroke and MI in O City over 24 years were classified into four six-year periods: 1999-2004 (Period 1), 2005-2010 (Period 2), 2011-2016 (Period 3), and 2017-2022 (Period 4).

Results: Age-adjusted death rates from stroke and IS decreased in both men and women, while those from HS remained unchanged. However, the age-adjusted incidence of stroke and IS in men and women decreased from Periods 1 to 2 but increased from Periods 2 to 4. In women, the age-adjusted incidence of HS increased from Periods 2 to 4, whereas in men, the incidence of HS remained unchanged. In both men and women, the age-adjusted death rate of MI decreased. In women, the age-adjusted incidence of MI decreased from Periods 1 to 4. The age-adjusted incidence of MI in men did not change over time.

Conclusion: For both men and women during the 24 years of follow-up, the age-adjusted death rates from stroke and MI decreased from Periods 1 to 4; however, the age-adjusted incidences of stroke and IS increased from Periods 2 to 4.