Diabetic patients with normal baseline renal function are at increased risk of developing contrast-induced nephropathy post-percutaneous coronary intervention.

INTRODUCTION: We hypothesised that diabetic patients with normal baseline renal impairment who do not receive prophylaxis before percutaneous coronary intervention (PCI) are at an increased risk of developing contrast-induced nephropathy (CIN).
METHODS: We conducted a cohort study involving 839 patients who underwent PCI between 2004 and 2006, and divided them into three groups: Group A (304 diabetics with normal baseline serum creatinine [Cr] of less than 1.5 mg/dL); Group B (465 non-diabetics with normal Cr); Group C (70 patients with impaired baseline renal function with Cr more than or equal to 1.5 mg/dL). CIN prophylaxis, including oral N-acetylcysteine and saline hydration, were administered only to Group C patients.
RESULTS: The median age for Groups A, B and C was 58, 56 and 64 years, respectively. The prevalence of hypertension in Groups A, B and C was 76.3, 56 and 85.7 percent, respectively. Baseline demographics were comparable among the three groups with regard to gender, left ventricular systolic function and contrast volume use. Incidences of CIN in Groups A, B and C were 8.9 percent, 4.3 percent and 4.5 percent, respectively (p-value is 0.042). The incidence of CIN in diabetic patients with a normal baseline Cr who did not receive prophylaxis (Group A) was significantly higher than in the other two groups (p-value is less than 0.001).
CONCLUSION: Our findings suggest that diabetic patients, despite having a normal baseline Cr, are at an increased risk of developing CIN post-PCI. Routine prophylaxis in this cohort may be beneficial.