Medical Monday – August 8, 2016
Medical Monday is a service of Project RACE for the multiracial community. We seek, gather, and list health articles of interest to interracial families and people of all races. We welcome health information from outside sources as long as the original source is cited.
1. Minorities less likely to have knee replacement surgery, more likely to have complications
American Academy of Orthopaedic Surgeons
- Morphology and Prevalence Study of Lumbar Scoliosis in 7,075 Multiracial Asian Adults
The Journal of Bone and Joint Surgery
3. Diversity in the Ophthalmologist Workforce
Source: JAMA ophthalmology
If you have current medical news to contribute, please email it with the source and your contact information with MEDICAL NEWS SUBMISSION in the subject line to:
Risk factors for cardiovascular disease have disproportionately affected women and blacks, and while the gender gap has narrowed over time, black-white disparities have widened, reported authors of a large 10-year cohort study published Aug. 11 in the journal Circulation.
The study showed that factors such as high cholesterol and smoking account for less cardiovascular disease (CVD) risk than in the past, said Dr. Susan Cheng of Harvard Medical School in Boston and her associates. “However, the combined contribution of all traditional risk factors has remained substantially higher in women, compared with men, and in blacks, compared with whites,” the investigators said. “These sex- and race-based differences continue to be especially pronounced for hypertension and diabetes mellitus.”
The researchers calculated the population-attributable risks (PARs) of five major modifiable risk factors – smoking, hypercholesterolemia, hypertension, diabetes, and obesity – for the 10-year incidence of CVD among 13,541 participants in the Atherosclerosis Risk in Communities (ARIC) study. The cohort was 56% female, 26% black, and aged 52-66 years when examined during the time periods 1987-1989, 1990-1992, or 1996-1998, the investigators said (Circulation 2014 Aug. 11 [doi:10.1161/circulationaha.113.008506]).
The contribution of smoking and high cholesterol to CVD risk fell, (from 0.15 to 0.13 and from 0.18 to 0.09, respectively) during the study period, and the contribution of obesity stayed the same at 0.06, the researchers reported.
But by 1996-1998, diabetes mellitus accounted for significantly more CVD risk in blacks than whites (0.28 vs. 0.13), and the same was true for hypertension (0.36 vs. 0.21; P = .08) and all risk factors combined (0.67 vs. 0.48; P = .002), the researchers said. Similarly, PARs for women surpassed those for men for diabetes (0.21 vs. 0.14; P less than .0001) and hypertension (0.32 vs. 0.19; P = .02), they reported.
The racial differences suggest that prevention efforts based on traditional risk factors have benefited whites more than blacks, the researchers added. However, most blacks in the study were from the ARIC study center located in Jackson, Miss., so the race-based findings might be specific to that area, they noted.
“The reasons for persistent sex differences in attributable CVD risks over time are not yet clear,” said Dr. Cheng and associates. They added that sex-based differences could stem from clustering; underrecognition or undertreatment of risk factors in women; biological differences that are not yet understood; or nontraditional risk factors in men.
The National Heart, Lung, and Blood Institute funded the study. Dr. Cheng also received funding from the Ellison Foundation. The authors reported no conflicts of interest.
Source: Frontline Medical News
Thyroid disease risk varies among blacks, Asians, whites
An analysis that included active military personnel finds that the rate of the thyroid disorder Graves disease is more common among blacks and Asian/Pacific Islanders compared with whites, according to a study in the April 16 issue of JAMA.
Donald S. A. McLeod, F.R.A.C.P., M.P.H., of the QIMR Berghofer Medical Research Institute, Queensland, Australia and colleagues studied all U.S. active duty military, ages 20 to 54 years, from January 1997 to December 2011 to determine the rate of Graves disease and Hashimoto thyroiditis (a progressive autoimmune disease of the thyroid gland) by race/ethnicity. Cases were identified from data in the Defense Medical Surveillance System, which maintains comprehensive records of inpatient and outpatient medical diagnoses among all active-duty military personnel. The relationship between Graves disease and race/ethnicity has previously not been known.
During the study period there were 1,378 cases of Graves disease in women and 1,388 cases in men and 758 cases of Hashimoto thyroiditis in women and 548 cases in men. Compared with whites, the incident rates for Graves disease was significantly higher among blacks and Asian/Pacific Islanders. In contrast, Hashimoto thyroiditis incidence was highest in whites and lowest in blacks and Asian/Pacific Islanders.
The authors write that the differences in incidence by race/ethnicity found in this study may be due to different environmental exposures, genetics, or a combination of both.
- Donald S. A. McLeod, Patrizio Caturegli, David S. Cooper, Peter G. Matos, Susan Hutfless. Variation in Rates of Autoimmune Thyroid Disease by Race/Ethnicity in US Military Personnel. JAMA, 2014; 311 (15): 1563 DOI: 10.1001/jama.2013.285606
Single letter of DNA ‘defines hair color’
Changing just one letter of genetic code is enough to generate blonde hair in humans, according to a new analysis from researchers at the Howard Hughes Medical Institute in Chevy Chase, MD.
David Kingsley, of the Howard Hughes Medical Institute, has been studying the evolution of sticklebacks – the small fish that moved from the seas to colonize lakes and streams at the end of the last Ice Age – for the last 10 years.
Using the sticklebacks’ adaptive responses to different habitats as a case study, Kingsley and his colleagues have been able to identify molecular-level changes responsible for driving evolution. More recently, they have turned their attention to see how evolutions in the stickleback might apply to other species, such as humans.
The research that led Kingsley’s team to investigate the genetic code responsible for hair color initially concerned changes in stickleback pigmentation. As part of a 2007 study, they found that a change in the same gene had driven pigmentation changes in different populations of sticklebacks around the world.
Interestingly, they found that this genetic change was not unique to the stickleback.
Same gene in sticklebacks and humans controls pigmentation
“The very same gene that we found controlling skin color in fish showed one of the strongest signatures of selection in different human populations around the world,” Kingsley says.
The genome “is littered with switches,” the researchers suspect.
Different versions of this gene – called “Kit ligand” – in humans are associated with differences in skin color. In both fish and humans, Kingsley found, the genetic changes thought to be responsible for pigmentation differences take place in regulatory elements of the genome.
“It looked like regulatory mutations in both fish and humans were changing pigment,” Kingsley says.
But tracking down specific regulatory elements in the whole genome is like finding a needle in the proverbial haystack. “We have to be kind of choosy about which regulatory elements we decide to zoom in on,” Kingsley acknowledges.
As well as encoding a protein that develops pigment-producing cells, however, Kit ligand has many other functions. For example, it influences the behaviors of blood stem cells, sperm or egg precursors and neurons in the intestine.
The team was interested in seeing whether they could isolate the regulatory changes in Kit ligand responsible for hair color without affecting any of the gene’s other functions.
‘Switching on’ Kit ligand’s hair color-determining powers
To do this, a research specialist in Kingsley’s team – Catherine Guenther – cut out segments of human DNA in the implicated region and linked each piece to a reporter gene. When these genes correctly “switch on,” they produce a distinctive blue color.
Next, Guenther introduced these pieces of switched-on DNA into mice. This allowed the team to further narrow the scope of their search until they had isolated a single piece of DNA that switched on the gene activity for developing hair follicles.
Further examining the DNA in that regulatory segment, the team found that it was just a single letter of genetic code that differed between people who have different hair colors.
The versions of this DNA associated with different hair colors were then each tested on the Kit ligand gene using cultured cells. The “blonde” switch reduced the activity of the gene by about 20%, which led the researchers to conclude they had identified a critical component of the DNA sequence.
Mice were then engineered to have a Kit ligand gene placed under either the genetic switches for blonde or brunette hair. Kingsley explains the results:
“Sure enough, when you look at them, that one base pair is enough to lighten the hair color of the animals, even though it is only a 20% difference in gene expression. This is a good example of how fine-tuned regulatory differences may be to produce different traits. The genetic mechanism that controls blonde hair doesn’t alter the biology of any other part of the body. It’s a good example of a trait that’s skin deep – and only skin deep.”
Their work with switching on different hair colors has led the team to suspect that the genome “is littered with switches.” Kingsley thinks that the various activities of Kit ligand, as well as other genes, may be adjusted by very subtle DNA tweaks.
As well as leading to a better understanding of the molecular mechanisms involved in human diversity, Kingsley hopes that this work may lead to improving human resistance to many common diseases.
“The trick is,” he says, is finding “which switches have changed to produce which traits.”
Source: Medical News Today
This is a very interesting TedMed talk!
Macular degeneration, often age-related macular degeneration (AMD or ARMD), is a medical condition that usually affects older adults and results in a loss of vision in the center of the visual field (the macula) because of damage to the retina. It occurs in “dry” and “wet” forms. It is a major cause of blindness and visual impairment in older adults (>50 years). Macular degeneration can make it difficult or impossible to read or recognize faces, although enough peripheral vision remains to allow other activities of daily life.
- Race: Macular degeneration is more likely to be found in Caucasians than in people of African descent.
Source: From Wikipedia
Some people are more likely to wake up during surgical procedures than others. “Certain people are at higher risk,” says Daniel Cole, MD, a member of the American Society of Anesthesiologists. “They include those with a genetic resistance to anesthetics (red-heads, for instance, thanks to an otherwise harmless genetic mutation)….”
A multiracial person told me that she is reluctant to get deep sedation after she had the problem years ago and was told that anesthetics are given differently based on race and ethnicity. If you know anything about this, please comment or email me.-Susan
Biracial toddler in need of bone marrow donor
PASADENA, Calif. (KABC) — If you have cancer and need a bone marrow transplant, finding a life-saving match can be like finding a needle in a haystack. But for one little girl, the search is even more challenging. But doctors believe you can help.
Right from birth, 21-month-old Sofia Flores knew how to shine.
“She came out with her hand up to her head…ready for the world, eyes open,” said her mom, Erica Westfall.
Westfall says Sofia hit her developmental milestones early. But she was always getting sick.
In July, a urinary tract infection prompted her parents to bring Sofia to the emergency room. There, they got surprising news.
“It was just devastating,” said Westfall.
First, doctors diagnosed her with a rare form of leukemia that only affects one percent of children.
“There were days where she was getting chemotherapy for 10 hours,” said Westfall.
Then her leukemia progressed to acute myeloid leukemia.
“Most patients in her position do not survive without a bone marrow transplant,” said transplant specialist Dr. Jerry Cheng with Kaiser Permanente Los Angeles.
Cheng says no one in Sofia’s family is a match. Her dad is Mexican and her mom is white. International registries turned up nothing.
“We try not to think about it, honestly. Day to day, we don’t really think about the odds and the numbers and percents because that makes us cry,” said Westfall.
In addition to Sofia being biracial, her dad is from Puebla, a state in Mexico. Doctors say that makes finding a match more complicated.
“The ability to find a good match, it follows along your heritage and your ethnic roots. But with the amount of diversity, especially in a great city like L.A., we do get surprises once in a while,” said Cheng.
Sofia’s parents are working with marrow matching organization A3M to organize drives. The hope is to find matches, not just for Sofia, but for many patients like her. Registering requires a saliva sample. If you match, the process is similar to donating blood. It’s a small sacrifice that can save a life.
A3M is organizing a marrow drive at Villa Parke Community Center in Pasadena on Saturday from 12 p.m. to 6 p.m.
Below are a few paragraphs from a very important article about the need for race-based medicine by Henry I. Miller, a physician and fellow in Scientific Philosophy and Public Policy at Stanford University’s Hoover Institution. I urge you to follow the link to the full article at Project Syndicate. –Susan
Much of the current debate centers on whether race should be a criterion for inclusion in clinical trials – and, by extension, whether drug labeling should mention race specifically. Although the issues are complicated, the solution is simple: follow the data.
Some regard race-based medical treatment as necessary to reduce health disparities, while others view it as downright discriminatory. When BiDil was approved, Francis Collins, who was Director of the US National Human Genome Research Institute at the time, warned that “we should move without delay from blurry and potentially misleading surrogates for drug response, such as race, to the more specific causes.”
Of course, Collins was correct; race is a crude and incomplete mechanism for understanding genetic differences. But we must fight illness with the data we have, not the data we wish we had. Political and ethical sensitivities notwithstanding, drug testing, approval, and labeling must go wherever the evidence leads.
To read the entire article go to:
Source: Project Syndicate
Graphic Warnings On Cigarettes Effective Across Demographic Groups
The study is one of the first to examine the effectiveness of pictorial warning labels versus text-only labels across diverse racial/ethnic and socioeconomic groups. Although a growing body of research has shown that disadvantaged groups may differ in their ability to access, process and act on health information, little is known about communication inequalities when it comes to cigarette warning labels.
The study authors note that text-only cigarette warnings have been repeatedly characterized as unlikely to be noticed or have an impact, and cite prior research indicating pictorial warning labels are more effective.
“Interventions that have a positive impact on reducing smoking among the general population have often proven ineffective in reaching disadvantaged groups, worsening tobacco-related health disparities,” said Jennifer Cantrell, DrPH, MPA, and Assistant Director for Research and Evaluation at Legacy®, a national public health foundation devoted to reducing tobacco use in the U.S. “It’s critical to examine the impact of tobacco policies such as warning labels across demographic groups.”
Senior author Vish Viswanath, associate professor of society, human development, and health at Harvard School of Public Health, said, “There is a nagging question whether benefits from social policies accrue equally across ethnic and racial minority and social class groups. The evidence from this paper shows that this new policy of mandated Graphic Health Warnings would benefit all groups. Given the disproportionate burden of tobacco-related disease faced by the poor and minorities, mandating strong pictorial warnings is an effective and efficient way to communicate the risk of tobacco use.”
The new study, published January 14, 2013, in the journal PLOS ONE, examined reactions to cigarette warning labels from more than 3,300 smokers. Results show that hard-hitting, pictorial graphic warnings are more effective than text-only versions, with smokers indicating the labels are more impactful, credible, and have a greater effect on their intentions to quit. Moreover, the study found that the stronger impact of pictorial warnings was similar across vulnerable subpopulations, with consistent reactions across race/ethnicity, education, and income.
“The implementation of graphic warning labels appears to be one of the few tobacco control policies that have the potential to reduce communication inequalities across groups,” Cantrell said.
“Tobacco use is a social justice issue,” added Donna Vallone, PhD, Senior Vice President for Research and Evaluation at Legacy®. “Given that low income and minority communities have higher smoking rates and suffer disproportionately from tobacco’s health consequences, studies like this show us that graphic warning labels can help us reach these subgroups in a more effective way, ultimately saving more lives.”
Source: ScienceDaily and Harvard School of Public Health, via EurekAlert!, a service of AAAS.