Although more and more people are living longer with colorectal cancer, new research has found that black people with the disease aren't living as long as whites.
In an analysis of more than 14,000 patients with stage 2 and 3 colorectal cancer who had surgery to remove tumors, followed by treatment to prevent recurrence, the 1,218 African-American patients had a lower five-year survival rate than their white counterparts, according to researchers, led by Greg Yothers of the National Surgical Adjuvant Breast and Bowel Project Biostatistical Center in Pittsburgh.
Five years after diagnosis, 72.8 percent of white patients survived cancer, but only 68.2 percent of blacks survived.
Colorectal cancer isn't the only medical condition that disproportionately affects certain races. Black people, for example, have much poorer health outcomes for a number of diseases.
"Across the board, if you look at the 15 leading causes of death in the U.S., blacks have higher death rates than whites in about 12 of them, including heart disease, cancer and stroke," said David Williams, the Norman professor of public health at the Harvard School of Public Health.
"For individuals, adopting a healthy lifestyle and receiving recommended health screenings are first steps. Unfortunately, not all communities have the same access to the resources and health care services necessary for a healthy lifestyle and early detection of diseases like heart disease, cancer, and diabetes, which are among the leading causes of death," said Leandris C. Liburd, director of the Centers for Disease Control and Prevention's Office of Minority Health and Health Equity.
Poor access to care, a lack of health insurance and the fear of seeking medical care because of immigration status are among the biggest barriers. There is also a complex mixture of individual and societal factors that's behind the health disparities affecting people of color and, experts say, it's the conditions on the following pages that are among those that have a significant impact on them.
In the colorectal cancer study, black and white patients received the same treatment, but the survival rates differed.
"Biological differences, differences in general health, and disparities in health care outside the clinical trial are possible explanations for these findings ...," the authors wrote.
One of the main reasons for the racial disparities observed in patients with different kinds of cancer is that fewer minorities undergo routine cancer screenings.
"There are different perceptions of the need for regular checkups and regular screenings," said Dr. Olveen Carrasquillo, chief of internal medicine at the University of Miami Miller School of Medicine. "Also, colorectal cancer screenings are invasive and they are less likely to want to undergo a colonoscopy, so we have to stress the need for these tests in culturally appropriate messages."
More African-American women die from breast cancer even though they get mammograms nearly as often as white women, according to the CDC's Office of Minority Health and Health Disparities. The death rate for all cancers is 30 percent higher among blacks and twice as high for prostate cancer
"Even after screening, minorities are less likely to follow up if there's an abnormality," Carrasquillo said.
Even though an abnormal mammogram doesn't mean there is cancer, Carrasquillo said many women of color still don't follow up, sometimes out of fear that they have cancer. There are also language barriers, he said, and people might not understand testing instructions or information about the importance of screening.
Cancer is also likely to be more severe among people of color. "For black women who get breast cancer, the course of the disease is more likely to be severe and they are more likely to die in any given year," Harvard's Williams said.
The Office of Minority Health and Health Disparities also said women of Vietnamese descent suffer from cervical cancer at rates five times higher than white women do.
Carrasquillo said Vietnamese and other immigrant women are less likely to undergo Pap smears, which could result in part from cultural factors. Many recent immigrants, he said, aren't comfortable with a man performing a gynecological exam.
New CDC data published this week show that the number of people with heart disease declined overall between 2006 and 2010. Whites and Hispanics showed the biggest decreases in that time. Asians also saw a decline.
Cardiovascular disease rose slightly in the black and Native American populations.
Despite the downward trend among Hispanics, heart disease is the leading cause of death among minorities in the United States, according to the U.S. Department of Health and Human Services' Office of Minority Health.
Blacks and Hispanics are more likely to suffer from obesity and hypertension, two of the major risk factors for heart disease.
One of the main reasons, experts say, is because people of color often live in areas where there isn't a lot of access to quality health care or to better lifestyle choices.
"Areas of high racial segregation are areas of high concentrations of poverty and the absence of access to good schools, the absence of access to high-quality medical care, exposure to high levels of messages about tobacco and alcohol and low access to green spaces and areas to exercise," Williams said.
They also might not have many affordable healthy food options, he said.
Carrasquillo added that studies have shown that African-Americans are much less likely to get invasive cardiac screening procedures, such as angiograms.
"Doctors are less likely to recommend screening to blacks than to whites when all things are equal," he said. "We need to improve the cultural competency of doctors."
"In the beginning, AIDS affected mostly gay white men, but now, it's disproportionately affecting communities of color," said Robert E. Fullilove, associate dean of community and minority affairs at Columbia University's Mailman School of Public Health in New York City. "Fifty-one percent of new cases are among blacks and Hispanics."
The National Institute of Allergy and Infectious Diseases says injection drug use is one of the reasons leading to the spread of the disease among minorities.
"Despite the fact that there are large numbers of blacks and Hispanics being tested, one in five living with HIV is unaware of his status," Fullilove said.
Incarceration is a also a major contributor to disease transmission.
"One out of every four people living with HIV is going to pass through a jail or prison. Black men make up about 41 percent of the prison population and Hispanics make up about 18 percent, and both these populations are high-risk," Fullilove added.
Prisoners often engage in unsafe sex or drug activities, which spreads the disease. When infected inmates are released back into their communities, Fullilove said, those communities become vulnerable to the spread of HIV. Former inmates often can't get health care right away or have access to government assistance programs and might not be aware they are infected.
The biggest group at risk is men of color who have sex with other men.
"There's a lot of stigma against them in the community, so many are not getting tested because they don't want to answer questions about who they've been with," Fullilove explained.
These men don't share this lifestyle with their female partners -- known as "being on the down low" -- and often transmit the virus to them.
Stigma also affects the Latino community, said Dr. Octavio Vallejo, HIV/AIDS trainer at the UCLA Center for Health Promotion and Disease Prevention on the Office of Minority Health's website.
"Our people are afraid to be tested for HIV, in a great part because of the perception of the disease. There is a bit of fatalism: "It was my fate, I'm going to die,' but they don't know that now nobody has to die from AIDS," he said.
The risk of developing diabetes is markedly higher for Hispanics in the United States.
"Compared to non-Hispanic whites, the risk for having diabetes was 87 percent higher for Mexican Americans and 94 percent higher for Puerto Ricans," the CDC's Liburd said.
Latinos are also twice as likely to die from diabetes.
Obesity, one of the biggest contributors to diabetes, is a much bigger problem among Hispanics and blacks.
"Some of it is due to obesity, but it's also due to environmental issues, such as poor access to healthy foods and places where they can get physical activity," Miami's Carrasquillo said. "It's very different in minority communities."
Complications that arise from diabetes -- kidney disease, eye disease and coronary artery disease -- are more prevalent among minorities, as well, according to the federal government's Agency for Healthcare Research and Quality.
Diabetes also affects many more Native Americans. The Office of Minority Health and Health Disparities says about twice as many American Indians have diabetes compared to non-Hispanic whites. The Pima tribe of Arizona has one of the highest rates of diabetes in the world.
Data from the National Osteoporosis Foundation show that Asian-American women are at high risk for developing the disease.
More than half of Asian-American women who are 50 and older have low bone density, a sign that bones are weakening even though osteoporosis hasn't developed yet. About 20 percent of the same population of women are living with osteoporosis.
Asian and white women have similar risk factors, but certain lifestyle factors make Asians especially vulnerable. They tend to consume much less calcium, largely because up to 90 percent of Asians are lactose-intolerant.
Asian women also tend to be slender and small-boned, putting them at increased risk for bone fractures.