According to a new UCLA study, if you are a middle-aged Asian or African-American woman, your social class and level of education may play a major role in how likely you are to suffer bone fractures. The findings were published in the April edition of the journal Osteoporosis International.
The investigators followed Asian, African-American, and Caucasian women for nine years during midlife. It differed from most previous studies on socioeconomic status and osteoporosis risk that focused only on older white women and usually did not collect fracture information over time. They note that their findings increase the understanding of the importance of social class, and particularly education levels, in the fracture risk of mid-life women from different racial and ethnic groups.
Approximately 50% of postmenopausal women and 20% of older men will suffer an osteoporosis-linked fracture, noted lead author Dr. Carolyn Crandall, a professor of medicine in the division of general internal medicine and health services research at the David Geffen School of Medicine at UCLA. She explained, “The traditional paradigm of assessing fracture risk does not include consideration of socioeconomic factors, such as education and income. Examining the associations of socioeconomic status with fracture risk could help the targeting of individuals at risk of future fracture and inform the development of preventive strategies.”
For the study, the investigators accessed data on 2,167 pre-menopausal women from the Study of Women’s Health Across the Nation (SWAN) bone study. At the study onset, the women ranged in age from 42 and 52 when the study began; it comprised 592 African-Americans, 1,093 Caucasians, 223 Chinese, and 259 Japanese. At baseline, the women had provided complete information on their income, education, osteoporosis risk factors, and fracture occurrences. Each year for nine consecutive years, they reported on whether they had experienced any fractures since the last study.
The investigators found that among the non-white women, a higher education level was associated with decreased fracture incidence. The women with at least some postgraduate education had an 87% lower non-traumatic fracture rate than those with only a high school education. Furthermore, each additional year of education was associated with 165 lower risk of suffering a non-traumatic fracture. Even after accounting for income, the associations between higher education level and decreased fracture risk persisted. Among Caucasian woman, no relationship between fracture risk and education was found. Dr. Crandal explained, “Interestingly, neither income level nor difficulty paying for basics was associated with fracture risk. This may seem surprising, but previous studies had suggested that links between education and fracture risk may be more pronounced than links between income and fracture risk. This is probably because education reflects socioeconomic status both in childhood and young adulthood, whereas income and financial hardship only reflects current socioeconomic status. It suggests that socioeconomic status over the entire life course is more relevant than current socioeconomic status to bone health.”
The researchers proposed a theory to explain the association between education and lower osteoporosis risk among non-white women but not in white women. They proposed that minority-race women with less education encounter more life stresses than less-educated Caucasian women, and the stresses faced by less educated Caucasian women may not impact their bone strength enough to affect their fracture risk in mid-life.
The study did not reveal a cause-effect relationship between low education and high fracture risk; however, it adds to the growing body of evidence that health disparities exist in our society. The authors note that, in addition, the study might be limited by the fact that some fractures may not have been reported to the study investigators. However, despite the aforementioned shortcomings, the authors wrote that the findings still “highlight the need to elucidate the biological and behavioral mechanisms underlying the possible protective effects of higher educational level on osteoporotic fracture incidence so that we can better target individuals at risk of future fracture and design appropriate preventive strategies.”
