Diabetes mellitus and impaired glucose tolerance are underdiagnosed in intensive care units

OBJECTIVE: To evaluate the presence of diabetes mellitus and impaired glucose tolerance in intensive care unit inpatients. METHODS: The study included patients in post-surgical care for elective and emergency surgery and excluded those patients with known diabetes mellitus. To diagnose prior serum glucose level disorders, we considered the value of glycated hemoglobin (HbA1c) at the time of admission, classifying the patients as normal (<5.7%), glucose intolerant (5.7-6.4%) or diabetic (>6.4%). During the first 3 days of the patient's hospital stay, glycemic control and clinical complications were assessed. Mortality was monitored for 28 days. For the statistical analyses, chi-square, ANOVA, student's t, Kruskal-Wallis or Mann Whitney tests were used. RESULTS: Thirty patients were included in the present study, 53% of whom were women; the patients had a mean age of 53.4±19.7 years and an APACHE II score of 13.6±6.6. The majority of patients were admitted for severe sepsis or septic shock followed by post-operative care for elective surgery, oncological surgery, multiple traumas and emergency surgery. When classifying these patients according to HbA1c, despite the absence of a prior history of diabetes mellitus, only 13.3% had a normal HbA1c level, 23.3% had levels compatible with the diagnosis of diabetes mellitus and 63.3% had levels compatible with impaired glucose tolerance. We found a significant association between the diagnosis of diabetes mellitus or impaired glucose tolerance and the use of vasoactive drugs (p=0.04). CONCLUSION: A high prevalence of undiagnosed diabetes mellitus and impaired glucose tolerance was observed in inpatients at a general intensive care unit.