Stress Hyperglycemia in Non-Diabetic Hospitalized Patients: Clinical Implications, Predictors of Adverse Outcomes, and the Role of Glycemic Control – A Prospective Observational Study

Abstract

Background: Stress hyperglycemia (SHG), defined as transient elevation of blood glucose during acute illness in individuals without a prior diagnosis of diabetes mellitus, is a common and clinically significant finding in hospitalized patients. Despite its high prevalence, its independent contribution to morbidity and mortality across heterogeneous inpatient populations remains incompletely characterized. 

Aim: This study aimed to determine the prevalence of SHG in non-diabetic hospitalized patients, identify independent clinical and biochemical predictors of SHG, and evaluate its association with adverse in-hospital outcomes including mortality, intensive care unit (ICU) admission, and hospital length of stay (LOS). 

Methods: A prospective observational study was conducted over 18 months at a tertiary care teaching hospital. A total of 320 consecutively admitted non-diabetic adults (age ≥18 years) were enrolled. SHG was defined as an admission blood glucose ≥180 mg/dL with a glycated haemoglobin (HbA1c) <6.5%. Demographic, clinical, and laboratory data were collected at admission. Outcomes assessed included ICU admission, in-hospital mortality, acute kidney injury (AKI), and hospital LOS. Multivariable logistic regression was performed to identify independent predictors of in-hospital mortality and ICU admission. 

Results: The prevalence of SHG was 40.0% (n=128/320). Compared to non-SHG patients, those with SHG had significantly higher rates of ICU admission (45.3% vs. 20.8%, p<0.001), in-hospital mortality (17.2% vs. 5.2%, p<0.001), AKI (26.6% vs. 9.4%, p<0.001), and prolonged hospital LOS (11.4 ± 4.8 vs. 6.7 ± 3.1 days, p<0.001). On multivariable logistic regression, SHG independently predicted in-hospital mortality (adjusted OR 3.14, 95% CI 1.38–7.16, p=0.007) and ICU admission (adjusted OR 2.68, 95% CI 1.56–4.60, p<0.001) after adjustment for age, APACHE II score, and comorbid burden. A significant dose-response relationship was observed between
admission glucose tertile and adverse outcomes (p<0.001 for trend). 

Conclusion: Stress hyperglycemia is prevalent in non-diabetic hospitalized patients and independently predicts in-hospital mortality, ICU admission, and major adverse outcomes. Routine glycemic surveillance and timely targeted glycemic management in this population are essential to improve clinical outcomes