JHS study discovers less blood pressure 'dipping' among poor
By Carrie Holmstrom
Blood pressures during sleep drop farther in people of higher socioeconomic status than in the poorer and less educated, according to a recent publication from the Jackson Heart Study.
Nighttime blood pressure dipping, a normal drop of more than 10 percent during sleep, is important for a healthy heart.
Dr. DeMarc Hickson, assistant professor of medicine and biostatistician with the Jackson Heart Study, said less dipping can lead to multiple problems.
"People of lower socioeconomic status who don't experience as much dipping can have hypertension and other cardiovascular risks, such as myocardial infarction, stroke and overall poor health," he said.
The American Journal of Hypertension published Hickson's study in September 2011. The National Heart, Lung and Blood Institute and the National Institute of Minority Health and Health Disparities funded the study.
Hickson and his team recorded blood pressures from nearly 900 African-American volunteers in 20-minute intervals during 24 hours.
Participants also logged their sleep schedules.
Researchers organized the data into three income groups - $25,000 or less, $25,000 to $49,999 and more than $50,000 - and three education groups - high school diploma and less, one-to-three years of college and bachelor's degree and above.
They found blood pressures dipped the lowest in the highest income category. Additionally, the high-income group's blood pressures remained lower throughout the day.
Analyzed by education level, people with college experience or degrees dipped considerably more during sleep than their less-educated counterparts.
Higher blood pressures and less dipping indicate a person's cardiovascular system is more stressed. Long-term high blood pressure can lead to heart, circulatory, kidney and other diseases.
Health-care providers and individuals can address health disparities influenced by socioeconomic differences, Hickson said. For example, meditation, yoga, regular exercise and a healthy diet can help control stress.
All participants in Hickson's study are members of the Jackson Heart Study, an 11-year-old study of more than 5,000 African-Americans from the metro area. The National Institutes of Health funds JHS, which is a collaboration between UMMC, Jackson State University and Tougaloo College.
In 1996, the Centers for Disease Control and Prevention reported more than one-third of the deaths among African-Americans in Mississippi were a result of cardiovascular disease, indicating the need for education and research.
"As public-health practitioners, we need to better understand and address the health disparities that come along with lower socioeconomic status," Hickson said.