PCI benefits over fibrinolysis found in diabetic patients

MedWire News - Cardiology - PCI benefits over fibrinolysis found in diabetic patients


PCI benefits over fibrinolysis found in diabetic patients

11 July 2007

Arch Intern Med 2007; 167: 1353-1359

MedWire News: The beneficial effects of primary percutaneous coronary intervention (PCI) over reperfusion therapy in diabetic patients with ST-segment elevation myocardial infarction (STEMI) are consistent with those for non-diabetic patients, meta-analysis findings indicate.

Writing in the Archives of Internal Medicine, Jan Paul Ottervanger (Isala Klinieken, Zwolle, The Netherlands) and colleagues note that an increasing amount of evidence indicates that primary PCI improves outcomes of STEMI compared with fibrinolysis in the general population. But effects of both reperfusion and fibrinolysis may differ in diabetic patients, they say, and previous trials comparing the strategies in diabetic patients have produced conflicting data.

"In our analysis including a large number of patients, it was more clearly demonstrated that primary PCI is associated with improved survival after 30 days in both patients with and without diabetes," the team reports.

The researchers analyzed data from 19 trials that compared primary PCI with fibrinolysis for STEMI in a total of 6315 patients, 877 (14%) of whom had diabetes.

At 30 days, 401 (6.3%) patients had died. Mortality was significantly higher in patients with than without diabetes (9.4% vs 5.9%, p<0.001).

Primary PCI was associated with lower mortality than fibrinolysis in both non-diabetic patients (4.8% vs 6.9%, unadjusted odds ratio [OR]=0.69; p=0.001) and diabetic patients (6.6% vs 12.4%, OR=0.49; p=0.001).

Recurrent MI and stroke were also less common with PCI in patients with and without diabetes, with corresponding ORs of 0.33 and 0.60, and 0.58 and 0.40.

After adjusting for potential confounders, including age, gender, time to randomization, treatment delay, systolic blood pressure, anterior MI, previous MI, heart rate, and randomized treatment, primary PCI was independently associated with reduced 30-day survival (OR=0.64). This association held true in patients with diabetes (OR=0.50) and without diabetes (OR=0.68).

The authors note that these point estimates indicate a greater benefit of PCI in diabetic patients, in whom the absolute risk is higher than in non-diabetic patients.

"This observation may be the result of delay in initiation of therapy and longer ischemic time in diabetic patients, which may be related in part to atypical symptoms," they write. "In particular, thrombolytic therapy seems to be negatively influenced by longer time to initiation of therapy."

They add that impairment of microvascular flow after fibrinolysis in diabetic patients could also contribute to a more favorable effect with PCI.

"Wider application of timely primary PCI could be an important strategy to improve outcomes in the high-risk population of diabetic patients," Timmer and co-authors conclude.

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