Time trends in incidence, case fatality, and mortality of intracerebral hemorrhage

OBJECTIVE: To assess age- and sex-specific trends in incidence and 30-day and 1-year case fatality of intracerebral hemorrhage (ICH) in the Netherlands.

METHODS: Patients hospitalized for first ICH were identified through linkage of the national hospital discharge register and population register using ICD-9 code 431. We identified out-of-hospital deaths in the national cause of death register. Incidence, 30-day and 1-year case fatality, and total mortality rate were calculated by age and sex. We identified time trends by joinpoint regression analysis and Mann-Kendall tests.

RESULTS: We identified 41,068 cases of ICH (51% men) between 1998 and 2010, of which 6% were out-of-hospital deaths. ICH incidence declined in men and women younger than 75 years (p ≤ 0.01, not significantly in men 35-54 years) but remained stable in patients 75 years and older. Thirty-day and 1-year case fatality declined in patients younger than 75 years (not significantly in women 35-54 years). In patients aged 35 to 54 years, ICH mortality remained stable until 2003 and then declined slightly (annual percentage change [APC] men: -7.09%; 95% confidence interval [CI] -11.39 to -2.59; women: -8.67%; 95% CI -15.18 to -1.66). In patients 55 to 74 years, mortality declined in men between 1995 and 2010 (APC -4.55%; 95% CI -5.49 to -3.59) and in women between 1992 and 2010 (APC -3.51%; 95% CI -4.16 to -2.85). Mortality did not decline in patients aged 75 years and older.

CONCLUSION: In the Netherlands, ICH incidence, case fatality, and mortality rates have declined significantly in men and women younger than 75 years but remained stable in patients 75 years and older. The observed time trends may be explained by better prevention and treatment during the previous 2 decades of which the elderly do not seem to benefit.