Association Between Ethnicity and Postoperative Hyperglycemia in a Southeast Asian Population Undergoing Cardiac Surgery

Objective: Postoperative hyperglycemia is a known risk factor for adverse outcomes following cardiac surgery. Therefore, the authors investigated the association between ethnicity and postoperative hyperglycemia in a Southeast Asian multiethnic population undergoing cardiac surgery.

Design: Perioperative data were analyzed prospectively.

Setting: Perioperative data were obtained from 2008 to 2010 at the 2 main heart centers in Singapore.

Participants: Data from 911 adult patients were collected.

Interventions: All patients underwent elective cardiac surgery.

Measurements and main results: Perioperative variables, genetic associations, and outcomes of hyperglycemic versus normoglycemic patients were compared. Of the 911 patients analyzed, 47.7% (n = 435) were diabetic and 77.7% (n = 708) had postoperative hyperglycemia. Patients with postoperative hyperglycemia after cardiac surgery were more likely to have diabetes; be female, older, and more obese; and have hypertension and renal impairment. Patients of Indian ethnicity had a significantly higher incidence of postoperative hyperglycemia (86.7%, p = 0.043), as compared to Malays (79.1%) and Chinese (75.9%). Ethnicity was identified as an independent risk factor for postoperative hyperglycemia, with Indians having a significantly higher risk than Chinese (OR 2.115, p = 0.015). Although Indian ethnicity was associated with the presence of angiotensin-converting enzyme D allele (65.7%, p = 0.044), no genetic associations with postoperative hyperglycemia were identified. Postoperative hyperglycemia also was associated significantly with poorer outcomes of longer high-dependency unit stay and new-onset cardiac arrhythmias.

Conclusion: The authors' findings demonstrated Indian ethnicity as an independent risk factor of postoperative hyperglycemia, likely due to insulin resistance and exaggerated hyperglycemic stress response, emphasizing the need for ethnic-based data unique to each population group.