Profiling Heparin-Induced Thrombocytopenia (HIT) Antibodies in Hospitalized Patients With and Without Diabetes.

Heparin (H) anticoagulation in populations characterized by elevated platelet factor 4 (PF4) frequently elicits PF4/H antibodies, presenting a risk of heparin-induced thrombocytopenia. Recent studies have shown that anti-PF4/H enzyme-linked immunosorbent assays (ELISAs) detect antibodies in individuals never exposed to heparin. Platelet factor 4/H cross-reactive antibodies may result from PF4-mediated defense responses to injury or infection. This study questioned whether patients with diabetes are more likely to develop the endogenous cross-reactive antibodies. A comparison of healthy volunteers versus hospitalized patients with or without diabetes showed no significant differences in the prevalence of PF4/H ELISA-positive results. However, the group of patients who had both diabetes and an infectious condition had higher median antibody titer compared to other patients with or without diabetes regardless of reason for hospitalization. Higher PF4/H titers were also associated with patients with diabetes who were not on any medical therapy. In the future, determining whether PF4/H cross-reactive antibodies sensitize patients to respond adversely to heparin anticoagulation or predispose patients to other complications may be relevant to diabetes care.

EVALUATION OF OUTCOMES AND COMPLICATIONS IN PATIENTS WHO EXPERIENCE HYPOGLYCEMIA AFTER CARDIAC SURGERY.

OBJECTIVE: The objective of the study was to elucidate 30-day and long-term outcomes in patients experiencing postoperative hypoglycemia. METHODS: We conducted a retrospective review of patients who underwent cardiac surgery between September 4, 2007, and April 30, 2011, at Northwestern Memorial Hospital who had intensive treatment of hyperglycemia postoperatively. Of 1,325 patients, 215 experienced a hypoglycemic episode (blood glucose <70 mg/dL) within the first 3 postoperative days. A total of 198 were propensity-score (PS) matched to 363 patients without hypoglycemia. The analysis consisted of a comparison of 30-day cardiac outcomes and long-term mortality between those who experienced a hypoglycemic event and those who did not. RESULTS: Between patients who experienced hypoglycemia compared to those that did not, there were no significant differences in mean glucose values while on insulin drips (119.8 ± 33.5 mg/dL vs. 120.9 ± 30.5 mg/dL; P = .69) or subcutaneous insulin (122.0 ± 38.0 mg/dL vs. 127.2 ± 35.5 mg/dL; P = .11) or postoperative surgical complication rates (30-day mortality: 3.5% vs. 1.7%; complications (any): 40% vs. 42%; 30-day re-admissions: 13% vs. 13%; all cardiac complications: 35% vs. 31%; and all infections: 8% vs. 5%). Over an average of 5.1 ± 2.2 years following index surgery, there was higher all-cause mortality among those PS-matched who had experienced hypoglycemia compared to those who had not (log-rank P = .031), primarily due to those (n = 32) experiencing more than one episode of hypoglycemia. CONCLUSION: Postoperative hypoglycemia did not negatively impact immediate surgical complication rates but was associated with a significant risk of increased postoperative morbidity and long-term all-cause mortality in patients experiencing multiple episodes of hypoglycemia. ABBREVIATIONS: BG = blood glucose BMI = body mass index CARD = Cardiovascular Research Database HR = hazard rate PS = propensity score.