Belinda Needham is an assistant professor in the Department of Epidemiology. Her research interests include health disparities, biosocial interactions, and aging and the life course.
Despite growing recognition of social factors as fundamental causes of disease, relatively little is known about the underlying biological mechanisms. Several theoretical models share the assumption that the chronic stress associated with social disadvantage contributes to wear and tear on the body, which accelerates the rate of decline in physiological functioning. Leukocyte telomere length (LTL), a biomarker of cell aging, may provide a link between the stress associated with disadvantaged social status and biological aging. Telomeres are repeat sequences of DNA that cap the ends of chromosomes and promote chromosomal stability. Telomere shortening tends to occur with advancing chronological age and leads to cellular senescence in vitro. Several recent studies have shown that LTL is associated with morbidity and mortality, independent of chronological age. Furthermore, previous research has demonstrated an association between LTL and stressful life circumstances. My work on the social and psychosocial predictors of telomere length includes the first-ever study to examine the association between socioeconomic status (SES) and LTL in children, the first-ever study to examine the association between SES and LTL in a nationally representative US sample, and the first-ever study to examine the association between neighborhood disadvantage and LTL in adults. More recently, I have begun to examine the social determinants of DNA methylation, which has been proposed as an additional, potentially modifiable, biological mechanism underlying health disparities.
1. Needham, B. L., et al., Life Course Socioeconomic Status and DNA Methylation in Genes Related to Stress Reactivity and Inflammation: The Multi-Ethnic Study of Atherosclerosis. Epigenetics, 2015. 10:p. 958-969.
2. Needham, B.L., et al., Neighborhood characteristics and leukocyte telomere length: the Multi-Ethnic Study of Atherosclerosis. Health Place, 2014. 28: p. 167-72.
3. Needham, B.L., et al., Socioeconomic status, health behavior, and leukocyte telomere length in the National Health and Nutrition Examination Survey, 1999-2002. Soc Sci Med, 2013. 85: p. 1-8.
4. Needham, B.L., et al., Socioeconomic status and cell aging in children. Soc Sci Med, 2012. 74(12): p. 1948-51.