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

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.

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.

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.

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.