March 2011 - Researchers announced today in the American Journal of Epidemiology that despite the high level of spending on healthcare in the United States compared to England, Americans experience higher rates of chronic disease and markers of disease than their English counterparts at all ages. Why health status differs so dramatically in these two countries, which share much in terms of history and culture, is a mystery.
The study uses data from two nationally representative surveys (see info below) to compare the health of residents of the United States and England from 0 to 80 years, focusing on a number of chronic conditions and markers of disease. This research builds on previous studies by other scholars that focused primarily on older adults.
"A systematic assessment of cross-country differences in health by age group and type of condition provides necessary context for learning about why older residents of England suffer fewer chronic health conditions than their counterparts in the US," notes Melissa L. Martinson, Office of Population Research, Princeton University.
Health measures based on physical examinations and/or laboratory reports included the following risk factors or conditions: obesity, hypertension, diabetes, low high-density lipoprotein (HDL) cholesterol, high cholesterol ratio, and high C-reactive protein* in addition to self-reported health issues (see study for details). These are the same measures that were used in other recent analyses that compared health of older adults in the two countries.
Differences between the two countries are statistically significant for every condition except hypertension. The results were not sensitive to alternative definitions of hypertension and are consistent with previous findings of lower rates of hypertension in the United States than in England. The disease prevalence for the self-reported conditions (i.e. asthma, heart attack, angina, and stroke) is largely consistent with country reports and other previous studies.
Comparisons by age group indicate that most cross-country differences in health conditions and markers of disease at young ages are as large as those at older ages. This is the case for obesity, low HDL cholesterol, high cholesterol ratio, high C-reactive protein, hypertension (for females), diabetes, asthma, heart attack or angina (for females), and stroke (for females). For males, heart attack or angina is higher in the United States only at younger ages, and hypertension is higher in England than in the United States at young ages.
Higher rates of screening for some conditions, the greater use of certain healthcare procedures, and higher survival rates for cerebrovascular disease in the United States may represent partial explanations. However, given that the United States has higher age-specific mortality for every age group (except for those 65 or older), these differences cannot fully account for the observed cross-country differences in health conditions and markers of disease.
The allocation of health care resources may play a role. Despite the greater use of health care technology in the United States, Americans receive less preventive health care than their English counterparts. They have fewer physician consultations per year. Acute hospital visits are also shorter in the United States, potentially resulting in missed opportunities for follow-up. It is also possible that the cross-country differences in social or physical environmental conditions or lifestyle play a role.
*Obesity was calculated for respondents between 4 and 80 years of age, C-reactive protein, an index of inflammation, was measured for respondents between 18 and 80 years of age, and the other conditions were measured for individuals at least 12 years of age.
About the studies used in the article: Data were from the 1999-2006 National Health and Nutrition Examination Surveys for the US (n=39,849) and the 2003-2006 Health Surveys for England (n=69,084).
The NHANES is a comprehensive survey conducted by the National Center for Health Statistics in the United States continuously since 1999 (8). For our analyses, data from all available years of the continuous survey were used. Of the 41,474 observations from 1999-2006, 1,625 were excluded, leaving an analysis sample of 39,849 observations between the ages of 0 and 80 years. Respondents older than 80 years were not included due to a lack of comparability between the NHANES and HSE for this age group (NHANES includes age in one-year increments for those over 80, while the over-80 age group is top coded in the HSE, making it impossible to know the age distribution of the over-80 age group in that survey). Sample sizes vary across health measures because several conditions were assessed only for certain age groups.
The HSE is an annual cross-sectional survey of private households in England conducted by the Joint Health Surveys Unit of the National Centre for Social Research (9??). For our analyses, the 2003-2006 surveys were used because starting in 2003 appropriate weights are available to make the data nationally representative when multiple years are pooled together. The number of respondents in the 2003-2006 surveys was 71,717. Our primary analysis sample included 69,084 observations after 2,633 observations for those older than 80 years were dropped. However, some biological measures were collected from representative subsamples of approximately half of all respondents.
Source: Oxford University Press