August 1, 2014Circulation Cardiovascular Interventions38 citations
Association of Glycemic Control With Mortality in Patients With Diabetes Mellitus Undergoing Percutaneous Coronary Intervention
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Key Result
Baseline HbA1c >10% was associated with significantly higher long-term mortality after percutaneous coronary intervention compared with HbA1c ≤7% (HR 1.52; 95% CI 1.17-1.99; P=0.002).
Study Design
Type
Cohort (n=3,008)
Multicenter
No
Structured PICO
Does poor glycemic control (HbA1c >10%) increase long-term mortality in patients with diabetes mellitus undergoing percutaneous coronary intervention compared to well-controlled diabetes (HbA1c ≤7%)?
P
Population
3,008 consecutive patients with diabetes mellitus undergoing percutaneous coronary intervention between 1998 and 2008, evaluated for long-term mortality based on baseline HbA1c.
E
Exposure
Poor glycemic control (HbA1c >10%)
C
Comparator
Well-controlled diabetes mellitus (HbA1c ≤7%)
O
Outcome
Long-term mortalityhard clinical
Poor glycemic control (HbA1c >10%) at the time of PCI is associated with significantly higher long-term mortality in non-insulin-treated diabetic patients compared to those with HbA1c ≤7%.
Main Result
Hazard Ratio: 1.52 (95% CI 1.17–1.99)
p-value: p=0.002
Abstract
BACKGROUND: Diabetes mellitus adversely affects outcomes in patients undergoing percutaneous coronary intervention. The association of baseline hemoglobin A1c (HbA1c) at the time of percutaneous coronary intervention with long-term mortality is unknown. METHODS AND RESULTS: Consecutive patients with diabetes mellitus undergoing percutaneous coronary intervention between 1998 and 2008 were identified from our institutional database. Characteristics and outcomes of patients were compared based on HbA1c categories (≤7%, 7.1%-8.0%, 8.1%-9.0%, 9.1%-10.0%, and >10.0%). Among 3008 patients, 1321 had HbA1c ≤7%, 782 with HbA1c 7.1% to 8.0%, 401 with HbA1c 8.1% to 9.0%, 229 with HbA1c 9.1% to 10.0%, and 275 with HbA1c >10%. Compared with low HbA1c (≤7%), those with highest HbA1c (>10%) were younger (56.5 versus 67.5 years), had higher total cholesterol (188 versus 157 mg/dL), more insulin use (54% versus 26%), and presented more often with ST-segment-elevation myocardial infarction (10.9% versus 5.6%). Those with lower HbA1c (≤7%) more often had other comorbidities (more hypertension 90.4% versus 82.5% and chronic renal failure 14.4% versus 7.6%). On multivariable Cox proportional hazards modeling, survival analysis demonstrated a trend toward higher mortality with higher HbA1c. Compared with the reference group of patients with HbA1c ≤7%, patients with HbA1c >10% had a significantly higher mortality on follow-up (hazard ratio 95% confidence interval, 1.52 1.17-1.99; P=0.002). This difference was primarily seen among noninsulin users; however, insulin users had no significant differences in mortality among HbA1c categories. CONCLUSIONS: Patients with diabetes mellitus who were not on insulin and had poor glycemic control (HbA1c >10%) had significantly higher long-term mortality after percutaneous coronary intervention as compared with those with well-controlled diabetes mellitus, evidenced by HbA1c ≤7%. Insulin users, however, had similar rates of mortality among different HbA1c categories.