Management of acute coronary syndrome in special subgroups: female, older, diabetic and Indigenous patients.

While the evidence base for management of acute coronary syndrome (ACS) is extensive, some subgroups have been underrepresented or excluded from relevant clinical trials. These subgroups - such as women, older people, diabetic patients and Indigenous Australians - present clinical challenges for which there is limited evidence to guide optimal therapy. Women may have a different pattern of presentation, with potential for delays in diagnosis and worse outcomes in ST-elevation myocardial infarction, but there is no evidence that treatments affect them differently from men. Older people suffer from a high-risk, low-treatment paradox. This may be due to under-appreciation of the benefits of treatments for older people, or to good clinical judgement in avoiding harm from worsening age-related comorbidities. Patients with diabetes have a high risk of ACS and suffer worse outcomes. Moderate glycaemic control with close monitoring and avoidance of hypoglycaemia are recommended. Coronary artery bypass grafting is preferred to percutaneous coronary intervention for patients with diabetes and multivessel disease, although the latter is reasonable in single-vessel disease. Indigenous patients have a high prevalence of coronary disease, with more frequent coronary events at a young age, a heavy load of risk factors and poor outcomes after ACS. The complex sociocultural barriers to treatment are yet to be addressed adequately.