Derivation of the first clinical diagnostic models for dehydration severity in patients over five years with acute diarrhea

Abstract

Diarrheal diseases lead to an estimated 1.3 million deaths each year, with the majority of those deaths occurring in patients over five years of age. As the severity of diarrheal disease can vary widely, accurately assessing dehydration status remains the most critical step in acute diarrhea management. The objective of this study is to empirically derive clinical diagnostic models for assessing dehydration severity in patients over five years with acute diarrhea in low resource settings. We enrolled a random sample of patients over five years with acute diarrhea presenting to the icddr,b Dhaka Hospital. Two blinded nurses independently assessed patients for symptoms/signs of dehydration on arrival. Afterward, consecutive weights were obtained to determine the percent weight change with rehydration, our criterion standard for dehydration severity. Full and simplified ordinal logistic regression models were derived to predict the outcome of none (<3%), some (3–9%), or severe (>9%) dehydration. The reliability and accuracy of each model were assessed. Bootstrapping was used to correct for over-optimism and compare each model’s performance to the current World Health Organization (WHO) algorithm. 2,172 patients were enrolled, of which 2,139 (98.5%) had complete data for analysis. The Inter-Class Correlation Coefficient (reliability) was 0.90 (95% CI = 0.87, 0.91) for the full model and 0.82 (95% CI = 0.77, 0.86) for the simplified model. The area under the Receiver-Operator Characteristic curve (accuracy) for severe dehydration was 0.79 (95% CI: 0.76–0.82) for the full model and 0.73 (95% CI: 0.70, 0.76) for the simplified model. The accuracy for both the full and simplified models were significantly better than the WHO algorithm (p<0.001). This is the first study to empirically derive clinical diagnostic models for dehydration severity in patients over five years. Once prospectively validated, the models may improve management of patients with acute diarrhea in low resource settings.

Continuous diagnostic models for volume deficit in patients with acute diarrhea

“…Both studies have developed clinical diagnostic models for assessing dehydration severity from acute diarrhea using an ordinal outcome (none, some, or severe dehydration). The ordinal logistic regression models for the DHAKA study have undergone both derivation with internal validation and external validation, while the NIRUDAK study has undergone diagnostic model derivation with internal validation, and has planned external validation in 2022 [ 15 – 17 ]. Neither study has reported a predictive model for the amount of fluid deficit measured on a continuous scale.…”

“…The models developed in this paper are secondary analyses of the DHAKA and NIRUDAK datasets; sample sizes for each dataset were calculated, a priori, for use as clinical diagnostic models [ 15 – 17 ].…”

“…All statistical analyses were performed using R Version 3.6.3 [ 24 ]. Six different models were developed from 17 candidate predictors for DHAKA and 8 predictors for NIRUDAK (as described previously) [ 17 ].…”

“…A forward stepwise regression algorithm was used to select the variables included in each of the six types of models the best model via tenfold cross-validation using mean squared error to choose the number of forward steps to take [ 17 ]. The six models were then compared on various performance measures to choose the best one.…”

Clinical, Sociodemographic and Environmental Risk Factors for Acute Bacterial Diarrhea among Adults and Children over Five Years in Bangladesh

“…Data were collected from the "Novel, Innovative Research for Understanding Dehydration in Adults and Kids" (NIRUDAK) study, a prospective cohort study of patients over 5 years of age presenting with acute diarrhea to the short-stay rehydration unit at the International Center for Diarrheal Disease Research, Bangladesh (icddr,b)'s Dhaka Hospital between March 2019 and March 2020. 20 Ethical approval for the NIRUDAK study was obtained from the icddr,b and Rhode Island Hospital Institutional Review Boards (IRBs).…”