Stress hyperglycemia and newly diagnosed diabetes in 2124 patients hospitalized with pneumonia

Abstract

Objective: Our goal was to determine the association between random admission hyperglycemia and new diagnosis of diabetes after discharge in patients hospitalized with pneumonia.

Methods: Clinical data, including the Pneumonia Severity Index, were prospectively collected on all 2124 patients without diabetes admitted with pneumonia to 6 hospitals in Edmonton, Alberta, Canada. Admission glucose was classified as: normal (4.0-6.0 mmol/L, reference group) versus mild (6.1-7.7 mmol/L), moderate (7.8-11.0 mmol/L), and severe (11.1-20.0 mmol/L) stress hyperglycemia. New diagnosis of diabetes over 5 years was ascertained using well-validated criteria within linked administrative databases. Multivariable Cox models were used, and sensitivity, specificity, and likelihood ratios were calculated.

Results: Mean age was 68 years; 1091 (51%) were male, and 1418 (67%) had stress hyperglycemia. Over 5 years, 194 (14%) with stress hyperglycemia were diagnosed with diabetes. Compared with the 45 of 706 (6%) incidences of diabetes in normal glycemia patients (4.0-6.0 mmol/L), a strong graded increase in risk of new diabetes existed with increasing hyperglycemia: mild (59 of 841 [7%]; adjusted hazard ratio [aHR] 1.09; 95% confidence interval [CI], 0.74-1.61) versus moderate (86 of 473 [18%]; aHR 2.99; 95% CI, 2.07-4.31) versus severe (49 of 104 [47%]; aHR 11.43; 95% CI, 7.50-17.42). Among moderate-to-severe hyperglycemia (≥7.8 mmol/L) patients, the sensitivity, specificity, and positive and negative likelihood ratios for new diabetes were 57%, 77%, 2.1, and 0.6, respectively, with a number-needed-to-evaluate of 5 to detect one new case of diabetes.

Conclusion: Moderate-to-severe random hyperglycemia in pneumonia patients admitted to the hospital is strongly associated with new diagnosis of diabetes. Opportunistic evaluation for diabetes may be warranted in this group.