Trends in stroke attack rates and case fatality in the Hunter region, Australia 1996-2008

Abstract

Background: The Hunter area in New South Wales, Australia, is a well-defined geographical area with a population of 578,486 (2006). This paper presents trends from 1996 to 2008 for prospectively registered hospital admissions of adults aged 20 years and above with acute stroke.

Method: Crude, age-standardised and age-specific stroke attack rates per 100,000 population and case fatality rates at standard time points were calculated. A medical record audit of stroke and stroke mimics was undertaken to determine discharge coding accuracy.

Results: 9,796 acute stroke events were registered among 8,830 individuals at 14 public acute hospitals. Crude and age-standardised attack rates decreased consistently from 1996 to 2008. Crude rates fell from 184 to 176 per 100,000 population and age-standardised rates from 129 to 106 per 100,000 (attack rate reduction of 0.85% per year, p = 0.027; and 2.38% per year, p < 0.001, respectively). Annual attack rates for females were on average 27.70% (p < 0.001) lower than for males. Age-specific rates fell for each age bracket between 45 and 74 years. Case fatality rates remained constant. There was a 97.5% proportion of agreement between audit and coding.

Conclusion: This study demonstrates falling stroke attack rates but stable case fatality over 13 years in a mixed urban and rural population of New South Wales, Australia. It suggests benefits from cardio- and cerebrovascular prevention strategies; however, it also indicates that stroke remains a major disease burden in this region.