Length of stay and associated costs of obesity related hospital admissions in Ireland

BMC Health Services Research Length of stay and associated costs of obesity related hospital admissions in Ireland Akke Vellinga 1 2 Diarmuid O'Donovan 1 2 Davida De La Harpe 0 0 Population Health, Health Intelligence, Health Service Executive , Dublin , Ireland 1 Department of Health Promotion, National University Ireland , Galway , Ireland 2 Department of Public Health, Health Service Executive West , Galway , Ireland Background: Obesity is the cause of other chronic diseases, psychological problems, obesity shortens the lifespan and puts strain on health systems. The risk associated with childhood obesity in particular, which will accelerate the development of adult morbidity and mortality, has been identified as an emerging public health problem. Methods: To estimate the length of stay and associated hospital costs for obesity related illnesses a cost of illness study was set up. All discharges from all acute hospitals in the Republic of Ireland from 1997 to 2004 with a principal or secondary diagnostic code for obesity for all children from 6 to 18 years of age and for adults were collected. A discharge frequency was calculated by dividing obesity related discharges by the total number of diagnoses (principal and secondary) for each year. The hospital costs related to obesity was calculated based on the total number of days care. Results: The discharge frequency of obesity related conditions increased from 1.14 in 1997 to 1.49 in 2004 for adults and from 0.81 to 1.37 for children. The relative length of stay (number of days in care for obesity related conditions per 1000 days of hospital care given) increased from 1.47 in 1997 to 4.16 in 2004 for children and from 3.68 in 1997 to 6.74 in 2004 for adults. Based on the 2001 figures for cost per inpatient bed day, the annual hospital cost was calculated to be 4.4 Euromillion in 1997, increasing to 13.3 Euromillion in 2004. At a 20% variable hospital cost the cost ranges from 0.9 Euromillion in 1997 to 2.7 Euromillion in 2004; a 200% increase. Conclusion: The annual increase in the proportion of hospital discharges related to obesity is alarming. This increase is related to a significant increase in economic costs. This paper emphasises the need for action at an early stage of life. Health promotion and primary prevention of obesity should be high on the political agenda. - Background The prevalence of obesity and overweight has increased dramatically over the past decades and researchers are only gradually becoming aware of the gravity of the risk posed [1,2]. In particular, the risk associated with childhood obesity, which will accelerate the development of adult morbidity and mortality, has been identified as an emerging public health problem [3]. The possibility that the current generation of children could suffer greater illness or experience a shorter lifespan than that of their parents has been suggested to be possible [4]. Obesity is the cause of serious chronic disease. Health consequences of obesity include diabetes mellitus, asthma, sleep apnoea, gall bladder disease and a range of cancers [5]. Obesity is known to reduce quality of life and impact on psychological problems [2,4]. Overweight is a term principally used to describe a body mass index over the 95th percentile by age and gender [6]. Rates of obesity vary between 1020% for men and 10 25% of women in different countries [7]. In the Republic of Ireland a survey from 2001 found 39% of adults to be overweight and 18% obese [8]. Data for Irish children are scarce but a recent survey in one county (Mayo, West of Ireland) where public health nurses weighed and measured all school children aged five to seven showed that 27% were overweight or obese with overall 7% of the six year olds obese [9]. Data from cross national surveys in which weight and length were self reported indicate that 13.7% of the Irish children between 10 and 16 years of age were overweight [10]. Many ubiquitous ties to a variety of health conditions, population level approaches to estimations of the total cost burden range from 2% of the national health care budget for most industrialised countries to up to 57% in the United States [11]. According to the report of the Irish National Task force on Obesity (2005), estimated inpatient cost of obesity as primary diagnosis in 2003 were just over 150,000 and the proportion of diagnosis attributable to obesity was estimated to be just under 30 million based on an estimation of the relative risk ratio [12]. An approach used by Wang et al (2002) to calculate the economic burden of obesity using primary and secondary discharge codes showed it to be a more precise to estimate obesity related hospital cost which include co-morbidities as well as allow for comparisons between years [13]. Following Wang's example, this paper analyses the length of stay and hospital costs associated with obesity and related conditions for adults aged 18 and older and for children aged between 6 and 17 inclusive. To analyse the change in obesity related hospital stays data were extracted from 1997 to 2004. Methods Data source The Hospital In-Patient Enquiry (HIPE) is the principal source of national data on discharges from all acute hospitals in the Republic of Ireland [14]. Hospital chart information is entered by trained HIPE coders into a computer. Each HIPE record represents one episode of care. Over 60 acute public hospitals participate in HIPE reporting on around 900,000 admissions annually. Over the years different adaptations of the database have been introduced. Until 2001, up to 6 diagnoses were included for each discharge, and from 2002 to 2004 up to 10 diagnoses have been included. The coding system used is the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). Discharges rather then admissions are used as HIPE is a hospital based discharge database; patients only enter the system once they leave the hospital. Since there are no unique identifiers available, multiple discharges are possible for one person. All discharges for obesity (ICD-9 code 278) were included. Obesity is described by the educational annotation of ICD-9-CM as an abnormal amount of fat on the body irrespective of BMI measurements and according to the consultants' judgement. The diagnostic code listed first was used as the principal diagnosis, and subsequent diagnostic codes (second through sixth or tenth) were used as secondary diagnoses. The codes for 'symptoms and signs of ill defined conditions' (ICD 780799) are assigned for symptoms and signs which are not directly linked to a specific disease. Analyses The obesity related hospital discharges from 1997 to 2004 were identified and extracted for all discharges for children from 6 to 18 years (? 6 and <18) of age and for adults (? 18). All principal (first listed diagnostic code) and secondary (second and higher codes) diagnoses were used. A discharge frequency was calculated (...truncated)