Diabetic patients with acute coronary syndromes in the UK: high risk and under treated. Results from the prospective registry of acute ischaemic syndromes in the UK (PRAIS-UK)

OBJECTIVES

Short-term randomised trials suggest that patients with diabetes mellitus (DM), admitted with acute coronary syndromes (ACS) are at increased risk of subsequent adverse events. We tested whether this hypothesis was true for an unselected population of ACS patients with and without DM admitted with non-ST elevation MI or unstable angina, in a non-trial setting over a longer term of follow-up.

METHODS

Prospective, centrally, coordinated multicenter registry involving 56 centers throughout the UK (half having angiographic facilities). Consecutive patients admitted with ACS without ST elevation on the presenting ECG were followed up to 6 months. A sub-group of patients were flagged with the UK Office for National Statistics and followed-up for death over 4 years.

RESULTS

Data were collected on 1046 ACS patients of whom 170 (16%) had a prior diagnosis of DM. DM patients had higher baseline co-morbidities and unadjusted mortality rates at 6 months (11.8% vs. 6.4%, p=0.01). After correcting for clinical variables such as age, gender, smoking status and chest pain/ischaemic ECG changes on admission, prior history of any of myocardial infarction, heart failure, hypertension, hypercholesterolemia (on treatment), stroke or coronary revascularisation (PTCA or CABG), mortality rates for DM patients were no longer significantly raised (hazard ratio 1.35, 95% CI: 0.79-2.30; p=0.27 at 6 months and 1.15, 95% CI 0.72-1.83 at 4 years). 30% of diabetics were dead after 4 years of follow-up. Patients with DM were more likely to have been revascularised at 6 months and were more likely to receive ACE inhibitors. Based on the rate of recruitment and the population covered in the study, about 21,000 patients with DM will be admitted with non-ST elevation ACS each year in the UK.

CONCLUSIONS

DM is common amongst patients admitted with ACS without ST elevation and is associated with significant morbidity and mortality: approximately 1 in 8 will not survive up to 6 months and 1 in 3 to 4 years. DM patients should be managed aggressively to reduce their risk of future complications.

Managing high-risk patients with acute coronary syndromes: the Prospective Registry of Acute Ischaemic Syndromes in the UK (PRAIS-UK)

A study was carried out to find out whether more intense treatment (both medical and revascularisation) is targeted towards higher-risk patients with acute coronary syndromes. A prospective UK registry of patients admitted with non-ST elevation acute coronary syndromes was established to examine practice patterns and clinical outcomes with respect to the risk profile of the patients. Clinically important high-risk subgroups included the elderly, diabetics, those with heart failure and those with ST depression or bundle branch block on the presenting ECG. Elderly patients were less likely to receive evidence-based treatments, including beta blockers, statins and revascularisation. Diabetics received more revascularisation procedures but the overall revascularisation rate was low. Heart failure patients received less evidence-based treatment, with the exception of angiotensin-converting enzyme (ACE) inhibitors. Heparin was used less frequently in those with a normal ECG, although rates of revascularisation were not different when compared with those with ECG abnormalities. The conclusions of the study were that groups of patients with particularly high event rates are readily identified by their clinical characteristics, but use of evidence-based treatments and invasive investigations do not appear to be targeted towards those at greatest risk. Risk stratification and the appropriate application of treatments for patients with acute coronary syndromes need to be reviewed in the clinical setting.