Stroke among Indigenous Australians at Royal Darwin Hospital, 2001–02

To the Editor: Although the age-standardised stroke mortality rates among Australia’s Indigenous people is more than twice that of the non-Indigenous population,1 the medical literature contains only one audit of Indigenous stroke patients in Perth metropolitan hospitals.2 No review of hospital care has been reported.

Royal Darwin Hospital (RDH) is the referral centre for Australia’s “Top End”, where 8.7% of Indigenous Australians reside; 40% of RDH inpatients are Indigenous. In 2002, while planning for the RDH stroke service, we audited stroke admissions from the previous year.

Among 121 eligible patients admitted between 1 July 2001 and 31 June 2002 with International classification of diseases, 10th revision, Australian modification (ICD-10-AM) codes 160–164 (haemorrhages [subarachnoid, intracerebral, other non-traumatic intracranial] and cerebral infarction), records for 116 (96%) were available, but six patients were excluded because of incorrect coding.

Box 1 outlines patient characteristics, while Box 2 examines risk factors and medication use for ischaemic stroke (because haemorrhages were few). Despite the observed differences between subgroups, there were no significant differences in mortality (4/36 for Indigenous v 7/42 for non-Indigenous; P = 0.204) or stroke severity at admission or discharge.

Box 3 highlights differences in risk factors between Indigenous males and females.

Retrospective data, particularly from a sample identified by medical record coding, should be interpreted with caution. In addition, the potential for random error due to small numbers, and the referral bias inherent in tertiary hospital admissions, mean our results may not truly represent the “Top End” Indigenous population. However, our data corroborate findings that Indigenous Australians suffer premature cerebrovascular disease, and have higher rates of vascular risk factors than other Australians,1 with some risk factor differences between males and females. Further, recent evidence suggests differences in standards of stroke care in regional (Queensland) hospitals.3 We found disparity in hospital care of Indigenous patients, and this requires further detailed investigation. A prospective, community-based study is urgently needed.