Underreporting of Obesity in Hospital Inpatients: A Comparison of Body Mass Index and Administrative Documentation in Australian Hospitals

Alexandra L Di Bella,Ingrid J Hickman,Elise M Gane,Donna F Hickling,Merrilyn Banks,Alisha Lucas,Adrienne M Young,Tracy Comans

doi:10.3390/healthcare8030334

Abstract

Despite its high prevalence, there is no systematic approach to documenting and coding obesity in hospitals. This study aimed to determine the prevalence of obesity among inpatients, the proportion of obese patients recognised as obese by hospital administration, and the cost associated with their admission. A cross-sectional study was undertaken in three hospitals in Queensland, Australia. Inpatients present on three audit days were included in this study. Data collected were age, sex, height, and weight. Body mass index (BMI) was calculated in accordance with the World Health Organization’s definition. Administrative data were sourced from hospital records departments to determine the number of patients officially documented as obese. Total actual costing data were sourced from hospital finance departments. From a combined cohort of n = 1327 inpatients (57% male, mean (SD) age: 61 (19) years, BMI: 28 (9) kg/m2), the prevalence of obesity was 32% (n = 421). Only half of obese patients were recognised as obese by hospital administration. A large variation in the cost of admission across BMI categories prohibited any statistical determination of difference. Obesity is highly prevalent among hospital inpatients in Queensland, Australia. Current methods of identifying obesity for administrative/funding purposes are not accurate and would benefit from reforms to measure the true impact of healthcare costs from obesity.

Highlights

The prevalence of obesity has tripled over the past three decades in Australia, with the latest figures from 2017–2018 indicating that 31.3% of Australian adults are obese [1,2,3] and a further 35.6% are overweight (BMI 25.00–29.99 kg/m2 ) [1]
The only study conducted within an Australian tertiary hospital of the point prevalence of obesity amongst inpatients reported a rate similar to local population norms of 25%, but with an over-representation of people classified as obesity class II and higher (BMI ≥ 35 kg/m2 ) [7]
In order to understand the potential influence of regional factors on prevalence rates of obese patients within acute hospitals, the findings from the present study make for an interesting comparison to those of a study conducted in a tertiary hospital in Perth, Western Australia

Summary

Introduction

The prevalence of obesity has tripled over the past three decades in Australia, with the latest figures from 2017–2018 indicating that 31.3% of Australian adults are obese (body mass index [BMI]of ≥30 kg/m2 ) [1,2,3] and a further 35.6% are overweight (BMI 25.00–29.99 kg/m2 ) [1]. Specific evidence is limited regarding the prevalence of obesity amongst inpatients of acute hospitals in Australia and the subsequent impact of obesity on the costs of those admissions. The only study conducted within an Australian tertiary hospital of the point prevalence of obesity amongst inpatients reported a rate similar to local population norms of 25%, but with an over-representation of people classified as obesity class II and higher (BMI ≥ 35 kg/m2 ) [7]. Studies consistently report that a considerable proportion of healthcare dollars is spent on the treatment and management of obesity-related conditions; the direct cost of obesity on hospital admissions remains unclear [8,9,10]

Objectives

Methods

Results

Discussion

Conclusion