A popular pastime for many older people is to try and figure out their chances of getting one ailment or another. Mayo Clinic researchers have simplified it – they have figured out the lifetime risk of developing rheumatoid arthritis and six other autoimmune rheumatic diseases for both men and women. “We estimated the lifetime risk for rheumatic disease for both sexes, something that had not been done before — separately or collectively,” says Cynthia Crowson Mayo Clinic biostatistician and first author. “Prevalence and incidence rates existed, but prevalence figures underestimate individual risk and incidence rates express only a yearly estimate.”
The researchers were looking for an accurate basis to offer an easy-to-understand average risk over a person’s lifetime, knowing that risk changes at almost every age. They used data from the Rochester Epidemiology Project, a long-term epidemiology resource based on patients in Olmsted County, Minn. The cohort of 1179, consisted of patients diagnosed between 1955 and 2007, allowed the team to extrapolate the nationwide estimates.
The adult lifetime risk in the United States of having some kind of inflammatory autoimmune disease is 8.4 percent for women and 5.1 percent for men. Based on year 2000 population figures, that means one woman in 12 and one man in 20 will develop one of the conditions in their lifetime. The authors consider that a substantial risk and say their findings should encourage more research on the value of early diagnosis and intervention for people with increased genetic risk of arthritis. They hope the new figures will help in counseling patients and in fundraising efforts to find improved treatments.
The research was supported by the National Institutes of Health.
A study of UK schoolchildren has revealed that Black Africans, Indians and Bangladeshis have a similar or lower prevalence of asthma than White children, while Black Caribbean and Mixed Black Caribbean/White boys are more likely to have asthma. Researchers writing in the open access journal BMC Pediatrics studied the occurrence of asthma, investigating ethnic differences in risk factors.
Melissa Whitrow and Seeromanie Harding from the Social and Public Health Sciences Unit of the Medical Research Council, UK, used data taken from 51 London schools to investigate a random selection of 11-13 year old pupils. The final sample for analysis included 1219 children who identified themselves as 'White UK', 933 'Black Caribbean', 1095 'Black African', 459 'Indian', 215 'Pakistani', 392 'Bangladeshi' and 299 'Mixed White UK and Black Caribbean'.
According to Whitrow and Harding, “Social and environmental factors may influence risk of asthma through early life exposures regulating the allergic inflammatory response and/or later life exposures to allergens. A positive association between body mass index (BMI) and asthma has also been reported. We aimed to investigate the influence of these factors on ethnic differences in asthma prevalence”.
The researchers found that a family history of asthma and psychological well-being were consistent correlates for asthma regardless of ethnicity. Less than six years of residence in the UK had an independent protective effect for Black Caribbeans and Black Africans, possibly reflecting continuing protection from early life exposures in their home countries. A gender difference was observed for Indians and Bangladeshis, with less asthma in girls than boys. Speaking about these results, the authors said, “These findings point to early protective influences which are not properly understood. International comparisons could provide useful insights into prevention of asthma, for ethnic minority children and for all children”.