Learning from History

For Black History Month -- a look at diseases that have historically affected African-Americans

/ Author:  / Reviewed by: Joseph V. Madia, MD

In recognition of Black History Month we're taking a look at diseases for which African-Americans are at higher risk -- and what to do about them.

African-Americans, compared to Caucasians and other ethnic groups, are at an increased risk of a number of diseases for reasons related to genetics, culture and/or socioeconomic disparities.

AIDS, glaucoma, heart disease, asthma, sickle cell anemia and diabetes are just a few of the conditions that have historically affected African-Americans more than some other ethic groups.

AIDS

Despite comprising only 13 percent of the overall United States population, African-Americans account for 45 percent of new AIDS (acquired immune deficiency syndrome) cases with gay and bisexual black men under age 30 accounting for more new HIV (the virus that causes AIDS) cases than any other race or age group.

A recent study from the University of North Carolina (UNC) Gilling School of Global Public Health found that a number of black men mistrust healthcare systems, which may account for some of these disparities. A survey of 610 African-American men over age 20 found many of these men delay getting routine check-ups because of a distrust of healthcare professionals.

Diabetes

More than 2.5 million African-Americans over the age of 20 have diabetes, with approximately one-third of them unaware of it. Nearly one-fourth of the black population over age 65 has diabetes.

A recent study from Louisiana State University Health Sciences Center New Orleans and Children's Hospital of New Orleans found a major difference between white and black children in relation to hemoglobin A1c (HbA1c) response to blood glucose, with African-Americans testing higher than Caucasians who have similar average glucose levels.

This difference in response rates may explain why blacks are at an increased risk of diabetes complications, by misleading physicians into believing their glucose levels are higher than they really are.

Stuart A. Chalew, MD, Professor of Pediatrics and Head of the Division of Endocrinology in the Department of Pediatrics at LSU Health Sciences Center New Orleans School of Medicine, said that if doctors don't take both HbA1c and self-monitored blood sugar levels into account, "they are likely to unintentionally provoke increased episodes of life-threatening hypoglycemia" in black patients.

Heart Disease

African-Americans are less likely to be diagnosed with heart disease than some ethnic groups but are more likely to die from it, part of which may result from the high fat, sugar and salt contents found in typical so-called soul foods.

A new study from Johns Hopkins University in Baltimore found that about a quarter of African-Americans have a gene known as CDKN2B that actually helps protect against heart disease, however.

The study followed 548 healthy African-American brothers or sisters of individuals with confirmed heart disease for 17 years and found about 25 percent of the volunteers had the protective version of CDKN2B (featuring a certain type of mutation called a single nucleotide polymorphism, or SNP), and 6 percent had two copies.

In spite of this protection, African-Americans are less likely than whites to be prescribed heart drugs or receive bypass surgery, in part because of socioeconomic disparities and access to health insurance coverage.

Cancer

African-Americans account for the highest cancer death rates in the United States. Every two years the American Cancer Society issues Cancer Facts & Figures for African-Americans, the latest of which reports black women die more often from breast and colorectal cancers while black men die more often from prostate, lung and colorectal cancers than white female and white male patients, respectively.

Death rates for all cancers remained 32 percent higher in African-American men and 16 percent higher in black women compared to white patients.

However, death rates from lung and other smoking-related cancers as well as prostate cancer are declining faster among African-American men than among white men.

On a more positive note, vigorous exercise for more than two hours per week has been shown to reduce the risk of breast cancer in postmenopausal African-American women by 64 percent, according to a study conducted recently at Georgetown Lombardi Comprehensive Cancer Center.

What to Do

By reaching out to African-American communities -- who are disproportionately represented in lower socioeconomic groups, according to Dr. Otis Brawley, chief medical officer of the American Cancer Society -- healthcare professionals should work to instill more trust in black patients while educating about safer sex practices and healthier eating and exercise regimens.
 

Review Date: 
February 3, 2011