Research

BUSM Research

Hair Aging Differs by Race, Ethnicity

While aging is an unavoidable biological process with many influencing factors that results in visible changes to the hair, there is limited literature examining the characteristics of hair aging across the races. A study in the Journal of Clinical and Aesthetic Dermatology now describes the unique characteristics of hair aging among different ethnicities that the authors hope will aid in a culturally sensitive approach when making recommendations to prevent hair damage during one’s lifetime.

Among the findings: hair-graying onset varies with race, with the average age for Caucasians being mid-30s, for Asians being late 30s, and for African Americans being mid-40s. Caucasians and Asians typically experience damage to the distal hair shaft, while African Americans see damage occurring closer to the hair root. Postmenopausal changes include decreased anagen (active or growing) hairs in the frontal scalp, lower growth rates, and smaller hair diameters.

“Despite a similar chemical composition, the structural properties of hair vary between different ethnicities and, consequently, the aging of hair differs as well. As the population ages and becomes more diverse, it is of greater necessity to understand the hairaging process in different types of hair,” says corresponding author Neelam Vashi, MD, associate professor of dermatology.

According to the researchers, the role of hair for both protection and cosmetic improvement makes it incredibly important to physical and mental well-being. “A thorough understanding of the unique characteristics of hair aging among different races and ethnicities is essential for the appropriate management of mature patients,” adds Vashi. n

Midlife Loneliness a Risk Factor for Dementia, Alzheimer’s Disease

Persistent loneliness during midlife (ages 45–64) appears to make people more likely to develop dementia and Alzheimer’s Disease (AD) later in life. However, people who recover from loneliness appear to be less likely to suffer from dementia, compared with people who have never felt lonely.

Loneliness is a subjective feeling resulting from a perceived discrepancy between desired and actual social relationships. Although loneliness does not itself have the status of a clinical disease, it is associated with a range of negative health outcomes, including sleep disturbances, depressive symptoms, cognitive impairment, and stroke. Still, feeling lonely may happen to anyone at some point in life, especially under extreme and unresolved circumstances such as the COVID-19 lockdowns. Yet, people differ in how long—or how “persistent”—they feel lonely for. Thus, it may be that people who recover from loneliness will experience different long-term consequences for their health than people who are lonely for many years.

In an effort to shed light on the relationship between these different forms of loneliness (transient and persistent loneliness) and the incidence of AD, researchers from BUSM examined data involving cognitively

normal adults from the Framingham Heart Study. Specifically, they investigated whether persistent loneliness more strongly predicted the future development of dementia and AD than transient loneliness. They also wanted to see whether this relationship was independent from depression and established genetic risk factors for AD, such as the Apolipoprotein ε4 (APOE ε4) allele.

After taking effects of age, sex, education, social network, living alone, physical health, and genetic risk into account, persistent loneliness was associated with higher risk, whereas transient loneliness was linked to lower risk of dementia and AD onset after 18 years, compared with no loneliness.

“Whereas persistent loneliness is a threat to brain health, psychological resilience following adverse life experiences may explain why transient loneliness is protective in the context of dementia onset,” explains corresponding author Wendy Qiu, MD, PhD, professor of psychiatry and pharmacology & experimental therapeutics. In light of the current pandemic, these findings raise hope for people who may suffer from loneliness now, but could overcome this feeling after some time, such as by using successful coping techniques or following a policy change in the physical distancing regulations.

The findings appear in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association. n

Plant-based Diets, Physical Activity Improve Heart Health

What if you could improve your heart health and brain function by changing your diet? BUSM researchers have found that by eating more plant-based food such as berries and green leafy vegetables while limiting consumption of foods high in saturated fat and animal products, you can slow down heart failure (HF) and ultimately lower your risk of cognitive decline and dementia. These findings appear online in the British Journal of Nutrition.

Adopting diets such as the Mediterranean diet (MIND) and the Dietary Approaches to Stop Hypertension (DASH), which are characterized by high intakes of plant-based foods, is among lifestyle recommendations for the prevention of HF. However, whether a dietary pattern that emphasizes foods thought to promote the maintenance of neurocognitive health also mitigates changes in cardiac structure and function (cardiac remodeling) has been unclear until now.

The researchers found the MIND diet, which emphasizes consumption of berries and green leafy vegetables while limiting intakes of foods high in saturated fat and animal products, positively benefited the heart’s left ventricular function, which is responsible for pumping oxygenated blood throughout the body.

“Our findings highlight the importance of adherence to the MIND diet for better cardiovascular health and further reduce the burden of cardiovascular disease in the community,” explains corresponding author Vanessa Xanthakis, PhD, assistant professor of medicine and biostatistics and an investigator for the Framingham Heart Study (FHS).

In another study that appeared in the Journal of the American Heart Association, using data from the FHS, Xanthakis has found following a routine of regular physical activity combined with a diet including fruits, vegetables, and other healthy foods may be key to middle-aged adults achieving optimal cardiometabolic health later in life.

Cardiometabolic health risk factors include the metabolic syndrome, a cluster of disorders such as excess fat around the waist, insulin resistance, and high blood pressure. Presence of the metabolic syndrome may increase the risk of developing heart disease, stroke, and type 2 diabetes.

“Healthcare professionals could use these findings to further promote and emphasize to their patients the benefits of a healthy diet and a regular exercise schedule to avoid the development of numerous chronic health conditions in the present and in later life,” Xanthakis says. “The earlier people make these lifestyle changes, the more likely they will be to lower their risk of cardiovascularassociated diseases later in life.” n