Differences in attitudes toward organ donation among African Americans and whites in the United States.

The availability of organs within the African-American population has been an on-going issue. Historically, African Americans donate organs at a much lower rate than whites. Thus, this study was designed to compare general attitudes between African Americans, whites, and other minorities concerning the issue of organ donation and to identify the factors that hamper African Americans from becoming organ donors. We conducted a 12-question survey of 249 African Americans, 492 whites, and a category of others defining themselves as 71 Asians, 23 Hispanics, 22 Native Americans, and 35 unknowns for a total sample of 892. Samples were taken from six United States cities. Thirty-eight percent of African Americans stated they would not donate organs, compared to 10% of whites. When asked why not, African Americans stated "personal reasons" followed by "if I am an organ donor I won't get the necessary medical attention" as their top choices. Whites chose "religious reasons" followed by "organs may be taken before I am dead" as their top choices. African Americans were more concerned with getting proper medical treatment as opposed to whites, who worried their organs might be taken before their death. Regarding family discussion pertaining to organ donation, 66% of African Americans stated no discussion. Whites had a 46% rate for no family discussion. Regarding trust of doctors, 46% of African Americans expressed lack of trust for doctors, with 23% of whites expressing lack of trust for doctors. The results of this study point to the areas that must be given more focus by African-American health care providers and educators.     

Cystic fibrosis on the African continent

Cystic fibrosis (CF; OMIM 219700) is a life-shortening and costly autosomal recessive disease that has been most extensively studied in individuals of Caucasian descent. There is ample evidence, however, that it also affects other ethnicities. In Africa there have been several reports of CF, but there has been no concerted effort toward establishing the molecular epidemiology of this disease on the continent, which is the first step toward outlining a public health strategy to effectively address the needs of these patients. A literature search revealed reports from only 12 of the 54 African states on the molecular analysis of the mutations present in suspected CF patients, resulting in the identification of 79 mutations. Based on previous functional investigations, 39 of these cause CF, 10 are of varying clinical consequence, 4 have no associated evidence regarding whether they cause CF, 4 are synonymous, 5 are novel, and 21 are unique to Africa. We propose that CF be more thoroughly investigated on the continent to ensure that the public health needs of African CF patients—both those in Africa and those of African descent living elsewhere—are met.Genet Med18 7, 653–662.     

Reactivity to spherule-derived coccidioidin in the southeastern United States.

Delayed hypersensitivity skin tests with mycelium-derived (coccidioidin) or spherule-derived (spherulin) antigens (or both) can be used to identify patients who have been sensitized to the dimorphic fungus Coccidioides immitis. Prior studies suggest that coccidioidin and spherulin skin test antigens detect comparable numbers of reactors among exposed subjects. Studies in subjects residing in areas outside the United States where C. immitis is not endemic suggest that both antigens are specific for the fungus. The specificity and reactivity of coccidioidin and spherulin have not been compared in nonendemic regions of the United States in which the skin test antigens and an appropriate travel or exposure history are used to identify patients with possible C. immitis infection. A review of delayed cutaneous reactions to coccidioidin in 6,375 patients tested between 1970 and 1979 in the southeastern United States revealed 958 (15.0%) and 234 (5.7%) positive reactions (greater than or equal to 5 mm), respectively, at 24 and 48 h. Subsequent tests with spherulin in 2,775 patients tested in 1980 and 1981 revealed 866 (31.2%) and 288 (10.3%) positive reactions, respectively, at 24 and 48 h. False-positive immediate hypersensitivity reactions contributed to the large number of spherulin reactors at 24 h. Differences among the patients sampled, work exposure, and travel history were excluded as causes of this surprising and highly significant (P less than or equal to 0.0001) difference in the 48-h delayed cutaneous reaction. These observations suggest two possibilities: (i) spherulin is less specific than coccidioidin, or (ii) a surprising prevalence of C. immitis sensitization exists among patients in nonendemic regions of the United States.     

Cystic fibrosis mutations in Israeli Arab patients

Mutation analysis was performed on 42 unrelated Israeli Arab CF patients. The previously known mutations in this population, DF508, N1303K, G542X, 4010delTATT, and S549R(T>G), were identified in 57 CF alleles, leaving 28 CF alleles with unknown mutations. Screening of the coding sequence of the CFTR gene by a single strand conformation analysis (SSCA) and direct sequencing revealed three point mutations and two intragenic deletions, including 2183AA>G, R75X, S549R (A>C), 3120+1Kbdel8.6Kb and del(exon2). In the present sample of Israeli Arab patients, 12 mutations account for 92% of the CF alleles. The mutations DF508, N1303K, W1282X and 3120+1Kbdel8.6Kb were found in all Arab ethnic subgroups. The mutations G85E, R75X, 2183AA>G, and del(exon2) were confined to Muslim Arabs, and the mutations 4010delTATT, S549R(A>C) and G542X were confined to Christian Arabs. Hum Mutat 14:543, 1999.     

Preconception and prenatal cystic fibrosis carrier screening of African Americans reveals unanticipated frequencies for specific mutations.

PURPOSE: It is recommended that cystic fibrosis (CF) carrier screening be made available to African Americans who are either pregnant or planning a pregnancy. We analyzed the carrier and mutant allele frequencies for African Americans undergoing CF carrier screening in our laboratories. METHODS: Between December 2001 and September 2003, we performed carrier screening for 2189 African Americans, testing for at least the 25 recommended mutations. RESULTS: A total of 33 CF carriers were identified. The most common mutations detected were deltaF508, G622D, R117H/7T, and G551D. The G622D allele frequency among African Americans was 0.18%. We did not detect any 3120 + 1G --> A carriers, although 4 were expected (P < 0.05). CONCLUSIONS: When considering only the 25 recommended CF mutations, 1 in 75 African Americans screened in our laboratories were carriers (within the expected range, given a 69% mutation detection rate). The addition of 2 mutations, G622D and Q98R (incidentally identified while screening for ACOG/ACMG mutations), increased the observed carrier frequency to 1 in 66, which is not significantly different from the known African American carrier frequency of 1 in 65. The frequencies of several specific mutations detected were unanticipated, as was the absence of 3120 + 1G --> A carriers. Further studies on African American patients with classic CF are needed to examine the incidence of CF mutations that are not part of the current panel, such as G622D.     

Cystic fibrosis mutations and immotile cilia syndrome

The immotile cilia syndrome (ICS) presents with autosomal recessive inheritance and is a chronic respiratory disease supposed to be caused by different genetic determinants. The hypothesis that cystic fibrosis (CF) heterozygotes may have a predisposition to develop bronchial or respiratory diseases other than CF prompted us to look for CF mutations in patients with ICS. Five patients, as well as the parents and two healthy brothers of one patient were tested for 12 CF mutations, for the polymorphic GATT repeat in intron 6a and for the CF gene flanking markers XV-2c, KM19, MP6d-9, J3.11. None of the 12 mutations at the CF locus have been detected in the ICS patients and no linkage was found between ICS and the polymorphic markers. Thus, based on our data, ICS and CF seem to be two different clinical entities.     

Diabetes mellitus among native Americans in Canada and the United States: An epidemiological review

Considerable ethnic variation in the prevalence of non–insulin-dependent diabetes mellitus (NIDDM) is recognized around the world and provides an interesting case study in the interaction of genetic and environmental factors in disease causation and distribution. Over the past one half century, numerous studies have shown that Native Americans, with some exceptions such as Arctic Eskimos and subarctic Athapaskan Indians, are generally a high risk group for NIDDM. There are, however, regional differences, reflecting the differential effects of genetic susceptibility, level of acculturation, and the contributions of specific risk factors such as physical activity, diet, and obesity. This paper reviews the extensive epidemiological, clinical, and anthropological literature on NIDDM among Native Americans in Canada and the United States. It discusses the extent and magnitude of the problem, etiology and risk factors, the public health impact of its serious complications, strategies for prevention and control, and current attempts to explain the prominence of this metabolic disorder among the indigenous inhabitants of the New World. © 1993 Wiley-Liss, Inc.     

Cystic fibrosis carrier frequencies in populations of African origin

Cystic fibrosis (CF) is a common autosomal recessive disorder in populations of European descent. However, very little is known about CF in populations of African origin among whom it has been believed to be extremely rare. The aim of this study was to determine if this is the case or whether it is under-reported. A CFTR mutation, 3120+1G→A, which was first reported in three African-American CF patients, has been shown to account for 9-14% of African-American CF chromosomes. It has also been found in 4/6 CF chromosomes in South African blacks and one CF chromosome of Cameroonian origin. In order to determine the carrier frequency of the 3120+1G→A mutation in Africa, 1360 unrelated, healthy subjects were screened. Nine carriers were identified. In addition, two out of five black CF patients with positive sweat tests were found to be heterozygous for the 3120+1G→A mutation and two out of another four black patients with symptoms suggestive of CF, but unconfirmed by sweat tests, were heterozygous for the D1270N mutation. A further three CFTR mutations, A559T, S1255X, and 444delA, which had been found in African-American CF patients, were not identified in the patients or in over 373 healthy subjects tested. The 3120+1G→A mutation has a carrier frequency of 1 in 91 (8/728) in South African blacks with a 95% confidence interval of 1 in 46 to 1 in 197. Since this mutation accounts for between 15% and 65% of CF chromosomes in South African blacks, a corrected CF carrier frequency would be between 1 in 14 and 1 in 59. Hence, the incidence of CF would be predicted to be between 1 in 784 and 1 in 13 924 births in this population. There are several possible reasons why these people are not being detected. Some of these are misdiagnosis as chronic pulmonary infection, malnutrition, tuberculosis, infantile diarrhoea, failure to thrive, or a high infant mortality rate.


Keywords: CF; African blacks; 3120+1G→A mutation; heterozygote frequencies     

Racial Disparities in Arterial Stiffness Between Healthy Whites and African Americans in the United States: A Meta-analysis

Background

African Americans (AAs) present with cardiovascular disease (CVD) risk factors at younger ages than whites. Consequently, CVD and stroke occur at a higher incidence and at earlier decades in life in AA populations. Arterial stiffness is a predictor of CVD outcomes and partially explains the CVD risk experienced by racial minorities. We evaluated the differences in arterial stiffness observed in AAs and whites through a systematic review and meta-analysis.

Asthma-related medication use among children in the United States.

BACKGROUND: Asthma is one of the most common chronic conditions in children and has a major impact on health care use and quality of life. The Best Pharmaceuticals for Children Act mandates the federal government to sponsor pediatric studies of drugs approved for use in the United States but lacking evaluation in the pediatric population and lacking interest of commercial sponsors. As input into the drug selection and prioritization process, information is needed on the percentage of children who receive asthma-related medications. OBJECTIVE: To estimate the percentage of children who receive asthma-related medications. METHODS: Retrospective analysis of outpatient medical and drug claims from members of commercial health care insurance plans enrolled any time from January 1, 2004, through December 31, 2005. The study population included 4,259,103 children throughout the United States aged birth through 17 years. RESULTS: Fifteen percent of all children were dispensed an asthma-related medication. Among 218,943 children with an asthma diagnosis, 188,286 (86%) had a dispensed asthma-related medication at any time during the 2-year study period. Among children without any asthma diagnoses, 398,880 (10%) had a dispensed medication. Fifty-nine percent of children with an asthma diagnosis were dispensed an anti-inflammatory medication within 90 days after a claim with a diagnosis of asthma. CONCLUSIONS: Asthma-related medications are dispensed to a large percentage of the pediatric population, including many who do not have claims with asthma diagnoses listed. Data on the pharmacokinetics and safety of these drugs in children are largely unknown and difficult to obtain. Clinical studies that use new tools and approaches are needed to resolve this information gap.     

HLA class II and TNF genes in African Americans from the Southeastern United States: regional differences in allele frequencies

Knowledge of population major histocompatibility complex gene frequencies is important for construction of organ donor pools and for studies of disease association. Human leukocyte antigen DRB1 (HLA-DRB1), HLA-DQB1, and TNFalpha -308 (G-A) promoter genetic typing was performed in 112 healthy, unrelated African Americans (AAs) from the southeastern United States. Allele frequencies were compared with published frequency data from other AA populations. Our AA population had the highest frequency of HLA- DRB1*09 (6.7%) reported in any AA population. The frequency of the TNF alpha -308A polymorphism was also high (14.4%), when compared with published frequencies in AAs. Significant regional differences in the distribution of most HLA-DRB1 and HLA-DQB1 alleles were observed in all AA populations examined. The AA HLA-DRB1 and -DQB1 frequencies also differed from published Caucasian frequencies. This is the first report describing the distribution of TNF alpha promoter alleles in the Southeastern United States. The high DRB1*09 and TNF alpha -308A allele frequencies of our population most resemble the frequencies of these alleles in certain West African populations. These varying major histocompatibility complex gene frequencies may reflect different regional population structures among AAs in the United States, which may be due to differences in ancestral origins, migration, and racial admixture.     

Cystic fibrosis mutations delta F508 and G542X in Jewish patients.

We have screened our CF patients for mutations in exons 10 and 11 of the CFTR gene. Two mutations, delta F508 and G542X, have been found in 66 Jewish CF patients. The average frequency of the delta F508 mutation in the Jewish population is 33.8%. The G542X mutation accounts for 13% of the Ashkenazi CF mutations and has been found in three out of seven chromosomes of Jewish patients from Turkey (probably descended from Ashkenazi immigrants). The G542X mutation was not found in any of the other non-Ashkenazi patients. All the G542X bearing chromosomes have the same haplotype. Based on these observations it is concluded that the G542X mutation was introduced into the Jewish people after the split into Ashkenazi and non-Ashkenazi.     

Awareness of cancer-related programs and services among rural African Americans.

African Americans are at increased risk for cancer and represent an important target population for programs such as Healthy People 2000, the Cancer Information Service (CIS), and the 5 a Day for Better Health Initiative. Yet, awareness of such programs among rural blacks is unknown. This study assessed awareness of these programs and determined related knowledge and beliefs among rural African Americans. It was undertaken as part of the baseline survey for the Black Churches United for Better Health project, a National Cancer Institute-funded initiative. A minority of respondents (n = 3737) demonstrated name recognition of Healthy People 2000 (23.4%), the CIS (42.4%), and the 5 a Day Program (40.7%). Far fewer (7.4%) were able to correctly identify the recommended daily number of servings of fruits and vegetables. Reported family history of cancer was associated with a greater tendency believe that eating more fruits and vegetables can prevent disease. These findings underscore the need for efforts to reach the rural black community with culturally sensitive and stage appropriate cancer prevention messages. Knowledge of family history of cancer may play an important role in targeting subgroups and delivering effective cancer prevention messages.     

Cystic fibrosis in Northern Ireland.

In a retrospective study of cystic fibrosis in Northern Ireland for 1961 to 1971, the incidence was 1 in 1857 livebirths, which is comparable to figures from Great Britain and the Republic of Ireland.