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Quality of Social Relationships May Accelerate Aging for African Americans

A University of Southern California (USC) Suzanne Dworak-Peck School of Social Work study published in the Journals of Gerontology: Social Sciences has uncovered evidence of racial differences in how family relationships—both positive and negative—can impact the biological aging of older adults, but more specifically older blacks.

The new study examined salivary telomere length (STL) to measure the impact of social relationships on premature aging. Telomeres are the protective DNA-based caps and protein structures at the tip of chromosomes—much like the plastic tips at the end of shoelaces. Telomeres shorten with each cell replication and with age. Shorter telomeres are an indicator of aging cells in the body; when they get critically short, individuals become more susceptible to age-related chronic health conditions.

While previous studies have focused on the effects of stress, depression and other factors on telomere length (TL) in general, none have looked at racial differences when examining the impact of social relationships related to TL.

"While we've known that social relationships are critical to both physical and mental health as people age, this is the first time we've seen that social factors are associated with cellular aging for older African Americans," says Karen Lincoln, PhD, lead author of the study and associate professor at the USC Suzanne Dworak-Peck School of Social Work. "Identifying modifiable factors that can slow the aging process in African Americans gives us an opportunity to develop approaches and interventions that could potentially extend the health span of this population."

In recent years, studies have shown that African Americans have higher mortality rates, and are more likely than whites to die at earlier ages from conditions that are more common in older adults, such as dementia, diabetes and kidney disease. This was recently confirmed in a study by the Centers for Disease Control in May 2017, which also found that younger African Americans live with or die from diseases that are more common in older whites. Other research in recent years has also shown African Americans to be biologically older by as much as five years than whites of the same chronological age.

Lincoln and her colleagues used salivary telomere data from the University of Michigan's Health and Retirement Study (HRS) that was released in December 2013. The HRS is a longitudinal panel study of more than 37,000 individuals older than 50 years and has been conducted every two years since 1990. It explores changes in the health transition of individuals toward the end of their work lives and in the years that follow. The USC study featured data from 4,080 HRS respondents who provided a saliva sample in 2008.

The researchers found that although social support from family was not associated with STL, ambivalent ties—represented by high levels of social support and more frequent negative interactions with family—were. Ambivalent ties are typical among close, tight-knit families. Negative interactions such as conflict and disagreements with family were associated with shorter STL for both African Americans and whites, but the magnitude of the association was stronger for African Americans.

"African Americans have subjectively closer ties than whites, and have more involvement and interactions with their family members, as well as more strained relationships," Lincoln says. "So the race difference might be due to differences in the type and quality of social ties, and the ability of these social relationships to buffer stress or promote healthier behavior patterns."

"This was a breakthrough finding because telomere shortening increases the risk of a wide variety of chronic diseases," Lincoln adds. "I believe that social relationships are a mechanism to understand accelerated biological aging, especially in African Americans. Our relationships with our family can be an avenue for intervention to alter the course of biological mechanisms of aging and increase the lifespan for those who would otherwise die at earlier ages."

Source: University of Southern California Suzanne Dworak-Peck School of Social Work