What are the predictors of new-onset diabetes in hospitalized COVID-19 patients?

By Tarun Sai LomteReviewed by Aimee MolineuxOct 18 2022

In a recent study published in the International Journal of Environmental Research and Public Health, researchers evaluated the incidence and predictors of new-onset diabetes (NOD) in patients hospitalized with coronavirus disease 2019 (COVID-19).

Background

Notwithstanding the measures introduced for prophylaxis and treatment of COVID-19, such as vaccines, antivirals, and monoclonal antibodies, the need for medical care and hospitalization remains high.

Numerous studies have reported that patients with severe COVID-19 have underlying comorbidities, such as cardiovascular disease, obesity, or hypertension. Reports suggest elevated morbidity and mortality rates in COVID-19 patients with type 2 diabetes mellitus (T2DM) than in those without T2DM, suggesting it may be an adverse prognostic factor.

About the study

The present study examined the incidence and predictors of NOD in COVID-19 patients. It was conducted on patients admitted to a Romanian hospital from November 10, 2020, to January 31, 2021. Patients aged 18 or above with any COVID-19 severity were included. Pregnant and diabetic individuals, patients hospitalized for less than two days, and those with missing biological specimens were excluded from the investigation.

NOD diagnosis during hospitalization was assessed using the criteria set by the American Diabetes Association. Mild disease was defined as having clinical symptoms without abnormal radiologic findings. Patients with pneumonia observed on a chest computed tomography (CT) scan were deemed as having a moderate disease.

Severe COVID-19 patients had respiratory distress, with a respiratory rate of ≥ 30/minute, peripheral oxygen saturation (SpO₂) of ≤ 93%, and arterial oxygen partial pressure to fractional inspired oxygen (P/F) ratio ≤ 300 mmHg. Critical patients were those with respiratory failure, multi-system organ failure, sepsis, or those requiring mechanical ventilation/intensive care unit (ICU) care.

Laboratory investigations were routinely performed; these included a complete blood count, D-dimer, C-reactive protein (CRP), lactate dehydrogenase (LDH), alanine aminotransferase (ALAT), triglycerides, arterial blood gas (ABG), aspartate aminotransferase (ASAT), creatinine, procalcitonin, and interleukin (IL)-6. Samples were collected from the day of hospitalization until discharge.

Findings

Of the 514 screened patients, 219 were included in the analysis. NOD was diagnosed in 58 subjects (26.5%) during hospitalization. The median age of the patients was 69, and most were males. Loss of taste and dyspnea were frequent among those with NOD. Notably, subjects with NOD often developed severe COVID-19 and required ICU care, with a longer median length of hospital stay (12.5 days) than those without NOD (nine days).

There were no statistically significant differences in the time from symptom onset to hospitalization and the use of corticoid therapy between patients with and without NOD. The incidence of NOD was higher in those admitted to ICU (43.3%) than those who were not (23.8%). NOD incidence increased with disease severity – 3.3% in patients with mild disease and 33.8% in severe COVID-19 patients. 

At admission, ferritin, fasting plasma glucose (FPG), and LDH were significantly elevated among NOD patients. Although hypoxemia was pronounced among NOD patients, it did not reach statistical significance. The peak levels of biochemical investigations (FPG, LDH, CRP, ferritin, triglycerides) were significantly elevated in NOD patients.

Univariate logistic regression revealed a significant association between COVID-19 severity, admission levels of FPG and LDH, peak neutrophil and leucocyte levels, CRP, and ICU care with NOD during hospitalization.

A lower odds ratio (OR) was observed for admission P/F ratio and peak IL-6 levels. Multivariable regression analysis was performed with variables that were significant in univariate analysis.

Overall, the whole regression model significantly predicted NOD during hospitalization. Nonetheless, only one variable (LDH at admission) significantly contributed to the model. LDH levels of 657 units/liter at admission significantly predicted NOD during hospitalization with a sensitivity and specificity of 52.7% and 73.6%, respectively.

Findings

The study noted that one in four COVID-19 patients had NOD during hospitalization. NOD incidence increased with COVID-19 severity and was higher in those requiring ICU care. Univariate analysis showed that the NOD group had a 2.7-fold increased risk of severe COVID-19. Multivariable analysis found that only admission LDH levels significantly predicted NOD during hospitalization, concordant with findings from a meta-analysis that noted a correlation between diabetes and LDH levels in COVID-19 patients.

In summary, the researchers observed a high incidence of NOD among patients hospitalized with COVID-19, with LDH at admission being the significant predictor of NOD. The authors suggested interpreting the findings with caution as the persistence of NOD post-COVID-19 remains unknown. Given the study’s retrospective nature, some methodological disadvantages may have occurred. Therefore, prospective studies must examine NOD persistence and the relevance of tested biomarkers.