Adult African American Patients Research Articles

Racial Disparity Trends for Graft Failure in the US Pediatric Kidney Transplant Population, 1980—2004

Graft survival among adult African American kidney transplant patients remains low compared to whites, but little information is available for children and adolescents. We examined trends in graft failure among US incident primary kidney transplant patients aged <19 years (n = 13 692), 1980-2004. Trends in 1-year and 2- to 5-year graft failure (for patients whose grafts survived the first year) were analyzed in 5-year intervals. One-year graft failure declined 70% for white and 77% for African American patients over the 25-year period, and 1-year graft failure rates improved at a slightly higher rate for African American compared to white patients (p = 0.02). In contrast, the graft failure rates for years 2-5 declined 53% for white and only 41% for African American patients over the 25 years (p = 0.29). In fully adjusted Cox proportional hazards analysis, the rate of graft failure among African Americans was approximately 2-fold higher than for white patients over the entire study period. Graft survival has improved slightly more for African American than white pediatric patients over the past 25 years. However, graft survival for African American pediatric patients remains poor compared with white patients.

Liver Transplantation Allocation System Shows Improvement in Racial, But Not Gender, Disparities

After the introduction of a new system in 2002 to determine the allocation of donated livers, African-American patients are no longer less likely to receive a liver transplant, but disparities for women remain, according to a study in the November 26, 2008 issue of JAMA. The Model for End-Stage Liver Disease (MELD) score has been used by the Organ Procurement and Transplantation Network since February 2002 as the basis for allocation of deceased donor livers for transplantation among adults in the United States. The MELD score predicts the risk of death within 3 months and is based on objective laboratory variables: bilirubin, creatinine, and a ratio for the prothrombin time. “In the current system, patients with higher MELD scores receive greater priority for organ allocation regardless of the amount of time spent on the waiting list,” the authors write. Dr Cynthia A. Moylan of the Duke University Medical Center and colleagues used a national database to determine whether racial or gender-based disparities exist in access to liver transplantation since the MELD system has been implemented. The study included adult African-American and white patients registered on the United Network for Organ Sharing liver transplantation waiting list between January 1996 and December 2000 (pre-MELD group; n = 21,895) and between February 2002 and March 2006 (post-MELD group; n = 23,793). African-American patients, compared with white patients, were younger (average age, 49.2 vs 52.4 years) and more ill (MELD score at listing: median [midpoint], 16 vs 14). Analyses indicated that the odds of death or becoming too ill for liver transplantation within 3 years of listing were higher among African-American verus white patients in the pre-MELD cohort (27.0% vs 21.7%), but not in the post-MELD group (26.5% vs. 22.0%). The researchers also found that African-American patients were less likely than white patients to receive liver transplantation within 3 years of listing in the pre-MELD cohort, but not in the post-MELD cohort. “This elimination in racial disparity in the post-MELD cohort likely reflects the fact that the MELD score now accounts for the severity of a patient's disease when listed,” the authors write. By contrast, gender was significantly associated with death and liver transplantation after adjusting for race, despite the use of the MELD score. Women were more likely to die or become too ill for liver transplantation within 3 years of listing in the post-MELD group (23.7% of women vs 21.4% of men) but not in the pre-MELD group (22.4% of women vs 21.9% of men). Women were also less likely to receive a liver transplant within 3 years of listing in both the pre-MELD and post-MELD groups. “Sex differences persist despite the use of MELD. Whether these differences result from true anatomic differences or represent a problem not addressed by the use of the MELD score mandates further investigation,” the report states. “The use of the MELD score allocation system appears to have reduced at least racial disparity in liver transplantation. We hope that ongoing investigations and refinements of MELD can provide even greater equity in the allocation of this precious resource.” “The MELD system has helped decrease disparities regarding the allocation of donated livers, writes Dr David A. Axelrod of the Dartmouth-Hitchcock Medical Center and Dr. Elizabeth A. Pomfret of the Lahey Clinic Medical Center, in an accompanying editorial. “When compared with the system before 2002, the current MELD system is clearly a step toward achieving the goal of an equitable, efficient, and transparent organ allocation system. The MELD system appears to have reduced, but likely not eliminated, differential access based on race and ethnicity. However, modest differences based on sex persist, but could be addressed by revisions in the organ allocation policy to ensure that MELD scores are comparable across sexes.” “The sex disparity is likely a reflection of several factors, including a limitation in the MELD calculation, body and organ size considerations, and potentially differences in the etiology of the underlying liver disease.” See “Disparities in Liver Transplantation Before and After Introduction of the MELD Score,” JAMA. 2008;300:2371–2378.

Coping as Predictor of Psychiatric Functioning and Pain in Patients with Sickle Cell Disease (SCD)

Coping is recognized as an increasingly important consideration in the management of chronic disease. Prayer, hostility and John Henryism appeared to be the most frequently discussed but least understood coping strategies associated with health outcomes in African Americans. The current study evaluated if prayer, hostility and John Henryism (JH) predicted psychiatric morbidity and pain in 67 adult African American patients with Sickle Cell Disease. We used a set of simple regressions to analyze continuous predictors (hostility and JH) and Analyses of Variance (ANOVA) to analyze the categorical predictor (prayer). Each of the coping variables was a statistically significant predictor of psychiatric morbidities. However, coping did not exert effects on the absolute value of pain. In summary, coping influenced reactions to pain but not reports of pain itself.

Outcomes in Adult and Pediatric Liver Transplantation Among Various Ethnic Groups

Background The reported patient and graft survivals among adults post–orthotopic liver transplantation (OLT) are variable, with an apparent discrepancy between ethnic groups. The aim of this study was to evaluate the impact of ethnicity on patient and graft survivals among adult and pediatric patients. Methods A retrospective analysis from the UNOS/OPTN databank between January 1995 and December 2006 was performed on adult and pediatric liver transplant recipients. Patients were divided into 4 groups based on ethnicity: African Americans, Hispanic, Caucasians, and other. Kaplan-Meier (KM) analysis was used to calculate patient and graft survival. Log-rank tests were used to compare survival rates between groups. Results In our study 42,710 OLT patients were included in the analysis, 90% of whom were adults. Of the 38,639 adult recipients, 29,432 (76.1%) were Caucasian, 4369 (11.3%) were Hispanic, 2963 (7.7%) were African American, and the remaining 1875 (4.9%) were of other ethnicities. KM estimates and Cox regression analyses demonstrated that there was a significant ethnic difference in both patient and graft survivals at 1, 3, 5, and 10 years. African Americans showed a lower rate ( P < .001). Of the 4341 pediatric recipients, 2461 (56.7%) were Caucasian, 797 (18.4%) were Hispanic, 824 (18.9%) were African American, and the remaining 259 (5.9%) were of other ethnicities. Unlike the adults, there were no significant differences among ethnic groups in terms of patient ( P = .31) and graft ( P = .33) survival at 1, 3, 5, and 10 years after OLT. Conclusion These results showed that adult African American OLT patients have a reduced transplantation rate and a worse survival rate when compared with other ethnicities in the adult but not in the pediatric population. This information suggests that further studies are indicated to identify the causes of racial differences in transplant access and outcomes in the adult patient population.

African Americans at Risk for Increased Iron Stores or Liver Disease

Purpose We sought to determine the prevalence of elevated measures of iron status in African Americans and whether the combination of serum ferritin concentration >200 μg/L for women or >300 μg/L for men and transferrin saturation in the highest quartile represents increased likelihood of mutation of HFE, self-reported iron overload or self-reported liver disease. Subjects and Methods A cross-sectional observational study of 27,224 African Americans ≥25 years of age recruited in a primary care setting was conducted as part of the multi-center, multi-ethnic Hemochromatosis and Iron Overload Screening (HEIRS) Study. Measurements included serum ferritin concentration, transferrin saturation, testing for HFE C282Y and H63D, and self-reported iron overload and liver disease. Results Serum ferritin concentration >200 μg/L for women or >300 μg/L for men occurred in 5263 (19.3%) of African Americans, while serum ferritin concentration in this range with highest-quartile transferrin saturation (>29% women; >35% men) occurred in 1837 (6.7%). Adjusted odds of HFE mutation (1.76 women, 1.67 men), self-reported iron overload (1.97 women, 2.88 men), or self-reported liver disease (5.18 women, 3.73 men) were greater with elevated serum ferritin concentration and highest-quartile transferrin saturation than with nonelevated serum ferritin concentration (each P <.05). Conclusions Serum ferritin concentration >200 μg/L for women or >300 μg/L for men in combination with transferrin saturation >29% for women or >35% for men occurs in approximately 7% of adult African American primary care patients. Patients with this combination of iron test results should be evaluated for increased body iron stores or liver disease.

Cancer Incidence in Sickle Cell Disease. Howard University, 1996–2004.

There are no prospectively collected data on cancer incidence and mortality in patients with sickle cell disease. This information would be a useful baseline for cancer surveillance, particularly in sickle patients exposed to potentially carcinogenic interventions such as hydroxurea administration and stem cell transplantation. A review of cancer cases among 696 adult sickle cell patients (mean age 28.8 y) at Howard University for the years 1986–1995 (2,684 patient-years, pt. yrs.) estimated the cancer incidence and mortality at 1.74 and 1.04 per 1000 pt. yrs, respectively (Am J Hematol 1997; 55:188). These figures were comparable to those reported for adult African American patients of similar age in the SEER database.Because sickle cell patients are now surviving longer, we examined again the cancer incidence and mortality at our institution for the years 1996 – 2004. In determining the patient-years of observation we assumed that if a patient was seen at least once during a given calendar year, the patient had been observed for that whole year. A total of 677 adult sickle cell patients (mean age 35.1 ± 12.5 y) were followed from 1996 through 2004 (2,317 pt.yrs.). There were 54.5 % females and 45.5 % males; the Hb genotype distribution was SS=70.5%, SC=19.2%, S-Thal=9.7%, and other=1%. The table shows the characteristics of 7 sickle cell patients who developed cancer during the study period. Their ages ranged between 38 and 64 years. All but one (Pt. 7) were female and all but one (Pt. 2) had Hb SS. Patients 1 and 3 had been treated with hydroxyurea.Based on these cases, the estimated cancer incidence was 3.02 per 1000 patient years, still below the upper 95% confidence limit in the 1986–1995 estimate (4.3 per 1000 patient years). Two additional cancer patients were seen at our institution, one with prostate cancer and the other with metastatic breast cancer. They were not included in the incidence estimate since they were specifically referred to our institution because of the cancer diagnosis. The current incidence of cancer in adult sickle cell patients at our institution is not increasing appreciably even though they are getting older and some are taking hydroxyurea.PatientAge (y)SexHb typeCancer type143FSSCervical carcinoma in situ238FSCHodkin's disease364FSSUterine carcino-sarcoma443FSSMetastatic adeno-ca., primary unknown557FSSRenal adenocarcinoma648FSSBreast cancer738MSSAnaplastic B-cell lymphoma (HIV)

Associations between the Impact of Terrorism and Health Perceptions of Patients

Previous studies have demonstrated the effects of the September 11th 2001 terrorist attacks on anxiety and anxiety-related conditions in Americans. However, data regarding associations between the attacks and patients' health perceptions are lacking. The objective of this study was to explore associations between the personal impact of the September 11th attacks and patients' perceptions of health and illness. We performed a cross-sectional survey of 303 adult African-American, Caucasian, and Hispanic patients at primary care clinics in Houston, Texas. Data were collected between October 15, 2001 and March 1, 2002. We developed items to measure the impact of the September 11th attacks and patients' quality of life. Previously validated scales were used to measure health status, health locus of control, preferences regarding the patient-physician relationship, and patients' explanatory models of illness. Twenty-two percent of patients reported no impact from the attacks, 41% reported mildly negative impact, 22% reported moderately negative impact, and 15% reported extremely negative impact in their lives. In multivariate analysis, demographic characteristics were not associated with impact from the attacks. However, patients who perceived a more external locus of control with respect to health and patients who reported greater meaning of illness in their lives also reported more negative impact from the September 11th attacks. The September 11th terrorist attacks had at least a somewhat negative impact for a majority of patients far from the site of the nearest attack, and regardless of their demographic backgrounds. The amount of negative impact that patients perceived as a result of the terrorist attacks correlates with certain illness perceptions, including an external health locus of control and a perception of greater meaning of illness in one's life. Such correlations may indicate an effect of terrorism on patients' illness behaviors. Further research is needed to better understand effects of the threat of terrorism on the general health and illness behaviors of patients.

Cardiovascular Magnetic Resonance in Cardiac Amyloidosis

Amyloidosis represents a diverse group of diseases characterized by the common factor of deposition of twisted β-pleated sheet fibrils (amyloid) formed as a result of the misfolding of various proteins produced in several different pathological states. The different forms of amyloidosis are classified by the composition of the amyloid fibril. AL amyloidosis (previously designated as primary amyloidosis) is derived from light-chain immunoglobulin produced by monoclonal plasma cells.1 It is the most severe and probably, at least in the United States, the most common form of amyloidosis. The accumulation of amyloid disrupts the tissue architecture and, possibly in conjunction with a toxic effect from the light chains,2 leads to severe organ damage that may involve the kidneys, heart, liver, or peripheral nerves. Familial amyloidosis is an uncommon, autosomal dominant disease with a high degree of penetrance. Most cases result from the production of an unstable variant of the serum protein transthyretin ( ATTR amyloidosis ). More than 80 point mutations have been identified for ATTR amyloidosis, which predominantly results in neurological or cardiac dysfunction or both.1,3 A particularly common mutant transthyretin resulting from the substitution of isoleucine for valine at position 122 is found in ≈4% of the African American population, with an unknown penetrance. This mutation results in a cardiomyopathy that has been suggested to be one of the most common types of cardiomyopathy in older adult African American patients.4 Senile systemic amyloidosis is the result of the deposition of wild-type transthyretin and is almost exclusively limited to the heart. This disease may be becoming more prevalent because of the increasing age of the general population. Reactive systemic amyloidosis is the result of an overproduction of a nonimmunoglobulin protein AA and is rarely associated with any cardiac involvement. See p 186 In AL amyloidosis, cardiac involvement is common …

To have and have not: Health and health care disparities in chronic kidney disease

A 50-year-old African American man came to the emergency room complaining of substernal chest discomfort over the past 2 months, as well as anorexia, general malaise, and decreased urinary frequency over the past 2 weeks. The patient stated that his chest pain lasted 2 to 3 minutes; did not radiate to the neck, jaw, or shoulder; was precipitated by lifting heavy objects; and did not occur at rest. He admitted to mild shortness of breath when walking up the stairs at home. He noted that for 2 weeks, he had been feeling exhausted and had had poor appetite, weight loss, and less frequent urination than usual. The patient had last seen a physician 4 years ago at an urgent care facility for a pilonidal cyst abscess. Five years prior to that, he had been told by a primary care physician that he had hypertension. He was treated with an unknown medication and, after a follow-up visit, was told that his blood pressure was normal. He has no other known history of cardiovascular or renal disease. He takes no medications. He lost his job as a cook and the health insurance that the job provided; he now says that he is unable to continue seeing the physician. He completed high school, is married, and works as a taxi driver as well as at a local farmers market on weekends. His father had hypertension and died suddenly at age 55. His mother is 71 and has diabetes. He has one older brother who

Gender and haplotype effects upon hematological manifestations of adult sickle cell anemia.

In Africa, the beta-globin gene cluster haplotype may be associated with variation of Hb F levels in subjects with sickle cell anemia (SS). These observations have not yet been conclusively confirmed in SS out of Africa, perhaps because of small sample sizes, the predominance of haplotype heterozygotes, and diverse influences, including gender, upon Hb F levels. We studied 384 adult African-American SS patients (mean age, 31 years) and explored the relationship of gender, beta-globin gene cluster haplotype, and alpha thalassemia to hematological values and Hb F levels. Both haplotype and gender influenced Hb F concentration. In the total sample, Hb F was higher in females than in males (8.2 vs. 6.5%). In 35 males who were either homozygous for the Senegal chromosome or had the Senegal/Benin haplotype, the mean percent Hb F (8.0%) was equivalent to the Hb F level in females with Benin and Bantu haplotypes (approximately 7.5%). Both females and males homozygous for the Senegal haplotype chromosome or with the Senegal/Benin combination had a significant increase in Hb F compared to other groups. In 44 Senegal/Senegal or Senegal/Benin females the Hb F was 10.9%, or 1.0 g/dl, the highest value observed in all primary analysis groups. Preliminary analyses suggested that the presence of a Bantu chromosome blunted the gender-associated difference in Hb F, but Hb F differences between females with the Senegal/Benin haplotype (11.2%) and the Senegal/Bantu haplotype (8.8%) were not statistically significant. Hemoglobin concentrations were higher in males than in females except in subjects with at least one Senegal haplotype chromosome, where hemoglobin levels were equal. As expected, alpha thalassemia reduced the MCV, increased hemoglobin concentration, and lowered reticulocyte counts, regardless of haplotype. Hb F levels were not affected by the presence of alpha thalassemia in any group. We conclude that gender and beta-globin gene cluster haplotype interact significantly in the modulation of Hb F and anemia in adults with SS.