Dengue clinical features and predictors of severity in the diabetic patient: a retrospective cohort study on Reunion island, 2019

Aim: Diabetes mellitus is associated with both the risks of severe dengue and dengue-related deaths, however the factors characterizing dengue in the diabetic patient are ill-recognized. The objective of this hospital-based cohort study was to identify the factors characterizing dengue and those able to predict dengue severity in the diabetic patient. Methods We retrospectively analysed demographic, clinical and biological parameters at admission in the cohort of patients who consulted at the university hospital between January and June 2019 with confirmed dengue. Bivariate and multivariate analyses were conducted. Results Of 936 patients, 184 patients (20%) were diabetic. One hundred and eighty-eight patients (20%) developed severe dengue according to the WHO 2009 definition. Diabetic patients were older and had more comorbidities than non-diabetics. In an age-adjusted logistic regression model, loss of appetite, altered mental status, high neutrophil to platelet ratios (>14.7), low haematocrit (≤ 38%), upper-range serum creatinine (>100 µmol/l) and high urea to creatinine ratio (>50) were indicative of dengue in the diabetic patient. In a modified Poisson regression model, four key independent variables were predictive of severe dengue in the diabetic patient: presence of diabetes complications, non-severe bleeding, altered mental status and cough. Among diabetes complications, diabetic retinopathy and neuropathy, but not diabetic nephropathy nor diabetic foot, were predictive of severe dengue. Conclusion At hospital first presentation, dengue in the diabetic patient is characterized by deteriorations in appetite, mental and renal functioning, while severe dengue can be predicted by presence of diabetes complications, dengue-related non-severe haemorrhages, cough, and dengue-related encephalopathy. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This monocentric observational retrospective study was conducted according to the reference methodology MR-004 from the National Commission of Informatics and Liberties. In accordance with French regulations, this retrospective study did not require approval from an ethics committee. The ethical character of the study on previously collected data was approved by the Institutional Review Board of the Centre Hospitalier Universitaire Reunion. The EPIDENGUE database was registered in the national health data hub (F20201021104344). Patients were informed of the study and non-refusal of participation was collected. Data was treated anonymously from patient medical records. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This monocentric observational retrospective study was conducted 159 according to the reference methodology MR-004 from the National Commission of Informatics and Liberties. In accordance with French regulations, this retrospective study did not require approval from an ethics committee. The ethical character of the study on previously collected data was approved by the Institutional Review Board of the Centre Hospitalier Universitaire Reunion. The EPIDENGUE database was registered in the national health data hub (n° F20201021104344). Patients were informed of the study and non-refusal of participation was collected. Data was treated anonymously from patient’s medical records. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors