Healthcare utilisation amongst those with Down's syndrome in Hong Kong : a population-based, cross-sectional study

Abstract

Down’s syndrome is a common chromosomal disorder associated with intellectual disability, congenital anomalies and increased risk of a number of acquired diseases. Despite improvements in life expectancy due to improved medical care, clear health disparities still exist. Down’s syndrome remains an important cause of infant mortality and intellectual disability in Hong Kong and globally. Gaps in existing knowledge include an unknown prevalence of Down’s syndrome, especially amongst adults; unknown patterns of A&E and outpatient utilisation by people with Down’s syndrome; the applicability of international data on hospitalisations of people with Down’s syndrome to Hong Kong; and the current demand on Hong Kong’s public healthcare services by people with Down’s syndrome.

This study uses Hospital Authority patient and healthcare episode data to identify people with Down’s syndrome alive in 2010. Data from the Hong Kong Census 2011 is then used to create an estimate of the age- specific point prevalence of Down’s syndrome in Hong Kong on 31/12/2010. The relative risk associated with Down’s syndrome of at least one admission is calculated. Age and gender stratified rates of A&E attendance, outpatient attendance and inpatient admissions for both the Down’s syndrome population and the general population are estimated and compared. Average length of stay is also calculated for both populations and compared. A negative binomial with log link regression model is used to examine the association between patient characteristics, including age, gender, ethnicity and known comorbidities, and admission factors, including admission type, admitting speciality, surgery and intensive care admission, on length of stay. Lastly, the proportion of Hospital Authority A&E attendances, outpatient attendances and inpatient admissions that are by people with Down’s syndrome is calculated.

2,144 people with Down’s syndrome were identified. The overall prevalence of Down’s syndrome on 31/12/2010 in Hong Kong was 3.00 per 10,000. It was highest in those aged under 5 years at 9.95 per 10,000 and decreased with age. Rates of A&E, outpatient attendance and inpatient admission were 2.0, 2.4 and 3.3 times higher respectively in the Down’s syndrome population compared to the general population. The Risk Ratio of at least one admission associated with Down’s syndrome was 2.59 (p<0.001). Factors significantly associated with increased length of stay included infant age group, known thyroid disease, known other circulatory malformation, non-emergency admission, surgery, admission to ICU and 3 or more known comorbidities. Known congenital heart disease and known epilepsy were significantly associated with a shorter length of stay. The overall proportion of A&E attendances, outpatient attendances and inpatient admissions that were by people with Down’s syndrome were 0.06%, 0.07% and 0.10% respectively.

This study provides new knowledge on Down’s syndrome in Hong Kong which will be of use to those delivering and planning healthcare services for this population, and also to those providing genetic counselling on Down’s syndrome. At the same time, new questions are raised on morbidity, mortality and equity of healthcare access amongst people with Down’s syndrome. Further research is required to answer these questions and thus allow effective interventions for reducing morbidity and mortality in this population to be designed.