Hospital-acquired pneumonia independently associated with elevated stress hyperglycaemia ratio at admission

This was independent of increased blood glucose, which was not a reliable indicator of stress-induced hyperglycaemia (SIH) and not independently associated with HAP.

Stress-induced hyperglycaemia as measured by the stress hyperglycaemia ratio is known to be tied to poor hospital outcomes such as increased infection rates. Elevated blood glucose has been associated with pneumonia when it is the primary cause of hospital admission. 

There is less clarity on whether SIH at admission independently drives new-onset infections. Therefore, Gregory Roberts, Flinders Medical Centre, Flinders Drive, Bedford Park, SA, Australia, and colleagues, therefore, assessed the relationship between early exposure at admission to both stress hyperglycaemia ratio and blood glucose (BG) with hospital-acquired pneumonia in an observational retrospective study.

They hypothesized that HAP is independently associated with early exposure to stress-induced hyperglycemia, and this is best represented by exposure to an acute increase from preadmission glycaemia, as represented by SHR ≥ 1.1 rather than exposure to BG ≥ 10 mmol/L.

The study included those with length-of-stay >1 day, recent haemoglobin A1c, and BG within 24 hours of admission. Stress-induced hyperglycaemia was defined as blood glucose≥10mmol/L, or SHR≥1.1, measured at both admission and as a 24-hour maximum. Multivariable analyses were adjusted for mechanical ventilation, chronic respiratory disease, age, and length of stay.

The authors reported the following findings:

· Of 5,339 eligible subjects, 2.1% experienced HAP.

· Admission SHR≥1.1 was independently associated with HAP (OR 3.04) but not BG≥10mmol/L (OR 0.65).

· The association with SHR strengthened using maximum 24-hour values (OR 3.37) while BG≥10mmol/L remained insignificant (OR 0.96).

· Of those experiencing HAP 40 (36.4%) occurred in subjects with no recorded BG≥10mmol/L but SHR≥1.1.

Stress-inducted hyperglycemia at admission defined as SHR≥1.1, but not the conventional marker of blood glucose ≥10mmol/L, was independently associated with the subsequent onset of HAP, commonly at BG<10mmol/L.

"This provides an incentive for controlled studies to manage and identify SIH at hospital admission as identified by the SHR, to reduce subsequent hospital-acquired pneumonia," the researchers concluded.

Reference:

Roberts, G., Chang, L., Park, J., & Thynne, T. (2023). The occurrence of Hospital-Acquired Pneumonia is independently associated with elevated Stress Hyperglycaemia Ratio at admission but not elevated blood glucose. Diabetes Research and Clinical Practice, 205, 110955. https://doi.org/10.1016/j.diabres.2023.110955