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Paul C Adams

Publications and source records attributed to Paul C Adams.

At least 19 recordsLinked to original sources
PubMed2025

Association of HFE genotypes with hemochromatosis-related phenotypes in the All of Us research program.

PURPOSE: Type 1 hereditary hemochromatosis (HH) can result in iron overload and liver disease if not detected and treated early. Most cases are found among people homozygous for HFE p.Cys282Tyr variants. Compound heterozygosity with the HFE p.His63Asp variant is associated with disease to a lesser degree. We sought to examine the association of HFE variation with HH-related phenotypes and assess the prevalence of testing and diagnosis of HH using All of Us data. METHODS: We used data from 133,978 participants with genetic information linked to medical records. For different HFE genotypes, we examined the prevalence of HH diagnosis codes and related biochemical and clinical phenotypes. RESULTS: Among participants who were p.Cys282Tyr homozygotes, the prevalence of HH diagnosis codes was 22.6% among males and 15.6% among females. Serum transferrin-iron saturation measures were available only for 31.4% of males and 21.1% of females who were p.Cys282Tyr homozygotes. Liver disease, including cirrhosis or hepatocellular carcinoma, was present more among males who were p.Cys282Tyr homozygotes compared with males with no p.Cys282Tyr or p.His63Asp variants (15.5% vs 8.5%, P = .0001). Of the 71 participants who were p.Cys282Tyr homozygotes with indication of liver disease, 32 (45.1%) did not have a serum transferrin-iron saturation measure, and 37 (52.1%) did not have diagnosis codes for HH. CONCLUSION: Limited serum transferrin-iron saturation measures or HH diagnosis codes among p.Cys282Tyr homozygotes, even those with liver disease, suggests potential undertesting and underdiagnosis of type 1 HH in clinical practice and a need for improved awareness, education, and testing around HH.

C282Y homozygosity↗
PubMed2006

Liver diseases in the hemochromatosis and iron overload screening study.

BACKGROUND AND AIMS: The Hemochromatosis and Iron Overload Screening (HEIRS) Study screened 101,168 primary care participants for iron overload with serum transferrin saturation (TS), ferritin, and C282Y and H63D mutations of the HFE gene. METHODS: All C282Y homozygotes and participants with an increased TS (>45% women, >50% men) and serum ferritin level (> 200 microg/L women, >300 microg/L men) were recalled for a clinical history and physical examination, and blood tests including alanine transaminase (ALT) and aspartate transaminase levels. Hepatitis B surface antigen and anti-hepatitis C virus were measured if the ALT level was increased (>31 IU/L in women, >40 IU/L in men). RESULTS: In the group of participants selected to return for clinical examination because of increased TS and ferritin levels, ALT increases and anti-hepatitis C virus were found in 95 of 284 (33%) African Americans, 50 of 466 (11%) Asian and Pacific Islanders, 21 of 120 (18%) Hispanics, and 40 of 477 (8.4%) Caucasians. ALT increases and hepatitis B surface antigen were detected in 24 of 466 (5%) Asian and Pacific Islanders, 10 of 284 (3.5%) African Americans, 3 of 120 (2.5%) Hispanics, and 2 of 477 (.42%) Caucasians. Of 86 liver biopsy specimens obtained for clinical purposes, 53 were reviewed by a single study pathologist. Liver fibrosis (stage 3 or 4) was present in 2 of 11 (18.2%) C282Y homozygotes that underwent central review and 2 of 302 (.66%) C282Y homozygotes attending the clinical examination. CONCLUSIONS: Screening for iron overload with ferritin and TS detects persons with viral hepatitis and other types of liver disease. A minimum of .66% C282Y homozygotes have liver fibrosis.

Adult↗
PubMed2006

Mixture models of serum iron measures in population screening for hemochromatosis and iron overload.

Homozygosity for the C282Y mutation of the hemochromatosis gene on chromosome 6p (HFE) is a common genetic trait that increases susceptibility to iron overload. The authors describe and apply methodology developed for the analysis of phenotypic and genotypic data from 46,136 non-Hispanic Caucasians, a subset of the multi-ethnic cohort enrolled in the Hemochromatosis and Iron Overload Screening (HEIRS) Study. For analysis of the distribution of transferrin saturation (TS), mixtures of normal distributions were considered and the expectation-maximization (EM) algorithm was applied for parameter estimation. Maximized log-likelihoods were compared, and significance was assessed by resampling. Sensitivity, specificity, and predictive values from the modeled subpopulations were compared with the actual observed genotypes for C282Y and H63D mutations in the HFE gene. A strong association between HFE genotype and TS subpopulations was found in these data collected from different geographic regions, confirming the external validity of the statistical approach when applied to population-based data. It was concluded that mixture modeling of phenotypic data may provide a clinical guide for screening with gender-specific thresholds to identify potential samples for genetic testing.

Adult↗
PubMed2006

The diversity of liver diseases among outpatient referrals for an elevated serum ferritin.

BACKGROUND: The aim of the present study was to examine the diversity of liver diseases in outpatients referred because of elevated serum ferritin. METHODS: A retrospective review was performed of outpatient referrals for serum ferritin elevations made to a tertiary care centre liver clinic between 1999 and 2005. Information regarding serum ferritin, transferrin saturation, liver biopsy, liver iron concentration and final diagnosis was extracted. Patients were stratified into two groups based on ferritin concentration: ferritin concentration 300 microg/L to 1000 microg/L, and ferritin concentration greater than 1000 microg/L. RESULTS: A total of 482 charts were reviewed, of which 119 (25%) had ferritin concentrations greater than 1000 microg/L. HFE-linked hemochromatosis, nonalcoholic steatohepatitis and alcohol-related liver disease were the top three diagnoses. HFE-linked hemochromatosis accounted for 28% to 42% of the diagnoses in all subgroups. The percentage of patients diagnosed with HFE-linked hemochromatosis was similar in the ferritin 300 microg/L to 1000 microg/L and the ferritin greater than 1000 microg/L groups (P = 0.067). Among patients with ferritin greater than 1000 microg/L, 63% underwent a liver biopsy. Of those with an elevated liver iron concentration (greater than 35 micromol/g dry weight), 71% had a transferrin saturation greater than 50% (88% of C282Y homozygotes and 43% of non-C282Y homozygotes). In non-C282Y homozygotes with an elevated serum ferritin concentration greater than 1000 microg/L, 64% did not have iron overload on liver biopsy. CONCLUSION: HFE-linked hemochromatosis accounted for less than one-half of the diagnoses in an outpatient population referred for elevated ferritin, suggesting a need to search further for an alternate cause.

Ambulatory Care↗
PubMed2006

Prognostic factors and survival in patients with hereditary hemochromatosis and cirrhosis.

OBJECTIVES: The survival of treated, noncirrhotic patients with hereditary hemochromatosis is similar to that of the general population. Less is known about the outcome of cirrhotic hereditary hemochromatosis patients. The present study evaluated the survival of patients with hereditary hemochromatosis and cirrhosis. METHODS: From an established hereditary hemochromatosis database, all cirrhotic patients diagnosed from January 1972 to August 2004 were identified. Factors associated with survival were determined using univariate and multivariate regression. Survival differences were assessed using the Kaplan-Meier life table method. RESULTS: Ninety-five patients were identified. Sixty patients had genetic testing, 52 patients (87%) were C282Y homozygotes. Median follow-up was 9.2 years (range 0 to 30 years). Nineteen patients (20%) developed hepatocellular carcinoma, one of whom was still living following transplantation. Cumulative survival for all patients was 88% at one year, 69% at five years and 56% at 20 years. Factors associated with death on multivariate analysis included advanced Child-Pugh score and hepatocellular carcinoma. Patients with hepatocellular carcinoma were older at the time of diagnosis of cirrhosis (mean age 61 and 54.6 years, respectively; P=0.03). The mean age at the time of diagnosis of hepatocellular carcinoma was 70 years (range 48 to 79 years). No other differences were found between the groups. CONCLUSIONS: Patients with hereditary hemochromatosis and cirrhosis are at significant risk of developing hepatocellular carcinoma. These patients are older when diagnosed with carcinoma and may have poorer survival following transplantation than patients with other causes of liver disease. Early diagnosis and treatment of hereditary hemochromatosis by preventing the development of cirrhosis may reduce the incidence of hepatocellular carcinoma in the future.

Adult↗
PubMed2006

A diagnostic approach to hemochromatosis.

In the present clinical review, a diagnostic approach to hemochromatosis is discussed from the perspective of two clinicians with extensive experience in this area. The introduction of genetic testing and large-scale population screening studies have broadened our understanding of the clinical expression of disease and the utility of biochemical iron tests for the detection of disease and for the assessment of disease severity. Liver biopsy has become more of a prognostic test than a diagnostic test. The authors offer a stepwise, diagnostic algorithm based on current evidence-based data, that they regard as most cost-effective. An early diagnosis can lead to phlebotomy therapy to prevent the development of cirrhosis.

Hemochromatosis↗
PubMed2006

Relationships of serum ferritin, transferrin saturation, and HFE mutations and self-reported diabetes in the Hemochromatosis and Iron Overload Screening (HEIRS) study.

OBJECTIVE: We evaluated the associations of self-reported diabetes with serum ferritin concentration, transferrin saturation (TfSat), and HFE C282Y and H63D mutations in six racial/ethnic groups recruited at five field centers in the Hemochromatosis and Iron Overload Screening (HEIRS) study. RESEARCH DESIGN AND METHODS: Analyses were conducted on 97,470 participants. Participants who reported a previous diagnosis of diabetes and/or hemochromatosis or iron overload were compared with participants who did not report a previous diagnosis. RESULTS: The overall prevalence of diabetes was 13.8%; the highest prevalence was in Pacific Islanders (20.1%). Of all participants with diabetes, 2.0% reported that they also had hemochromatosis or iron overload. The mean serum ferritin concentration was significantly greater in women with diabetes in all racial/ethnic groups and in Native-American men with diabetes than in those without diabetes. The mean serum ferritin concentration was significantly lower in Asian men with diabetes than in those without diabetes. Mean TfSat was lower in participants with diabetes from all racial/ethnic groups except Native-American women than in those without diabetes. There was no significant association of diabetes with HFE genotype. The mean serum ferritin concentration was greater (P < 0.0001) in women with diabetes than in those without diabetes for HFE genotypes except C282Y/C282Y and C282Y/H63D. Log serum ferritin concentration was significantly associated with diabetes in a logistic regression analysis after adjusting for age, sex, racial/ethnic group, HFE genotype, and field center. CONCLUSIONS: Serum ferritin concentration is associated with diabetes, even at levels below those typically associated with hemochromatosis or iron overload.

Adult↗
PubMed2006

Geographic and racial/ethnic differences in HFE mutation frequencies in the Hemochromatosis and Iron Overload Screening (HEIRS) Study.

OBJECTIVE: To assess geographic differences in the frequencies of HFE C282Y and H63D genotypes in six racial/ethnic groups recruited in the Hemochromatosis and Iron Overload Screening (HEIRS) Study. DESIGN: HFE C282Y and H63D genotypes of 97,551 participants, ages > or = 25 years, who reported that they belonged to one of six racial/ethnic groups, were analyzed. HFE genotype frequencies were compared among the racial/ethnic groups and among the HEIRS Study field centers within each racial/ethnic group. RESULTS: The distribution of HFE C282Y and H63D genotypes differed among racial/ethnic groups (P<.0001) and among field centers in Hispanics, Asians, Whites, and Blacks (each P<.05). Genotype frequencies were similar among field centers in Native Americans and Pacific Islanders. Frequencies of C282Y and H63D genotypes were greatest in Whites. The lowest frequencies of C282Y genotypes were observed in Asians; Blacks had the lowest H63D genotype frequencies and the highest frequency of the wild-type genotype. Among racial/ethnic groups, Hispanics had the greatest variation in HFE genotypes across geographic regions. CONCLUSION: HFE C282Y and H63D genotype frequencies vary significantly between racial/ethnic groups and within some racial/ethnic groups across geographic regions.

Adult↗
PubMed2005

Hemochromatosis and iron-overload screening in a racially diverse population.

BACKGROUND: Iron overload and hemochromatosis are common, treatable conditions. HFE genotypes, levels of serum ferritin, transferrin saturation values, and self-reported medical history were studied in a multiethnic primary care population. METHODS: Participants were recruited from primary care practices and blood-drawing laboratories. Blood samples were tested for transferrin saturation, serum ferritin, and C282Y and H63D mutations of the HFE gene. Before genetic screening, participants were asked whether they had a history of medical conditions related to iron overload. RESULTS: Of the 99,711 participants, 299 were homozygous for the C282Y mutation. The estimated prevalence of C282Y homozygotes was higher in non-Hispanic whites (0.44 percent) than in Native Americans (0.11 percent), Hispanics (0.027 percent), blacks (0.014 percent), Pacific Islanders (0.012 percent), or Asians (0.000039 percent). Among participants who were homozygous for the C282Y mutation but in whom iron overload had not been diagnosed (227 participants), serum ferritin levels were greater than 300 mug per liter in 78 of 89 men (88 percent) and greater than 200 microg per liter in 79 of 138 women (57 percent). Pacific Islanders and Asians had the highest geometric mean levels of serum ferritin and mean transferrin saturation despite having the lowest prevalence of C282Y homozygotes. There were 364 participants in whom iron overload had not been diagnosed (29 C282Y homozygotes) who had a serum ferritin level greater than 1000 microg per liter. Among men, C282Y homozygotes and compound heterozygotes were more likely to report a history of liver disease than were participants without HFE mutations. CONCLUSIONS: The C282Y mutation is most common in whites, and most C282Y homozygotes have elevations in serum ferritin levels and transferrin saturation. The C282Y mutation does not account for high mean serum ferritin levels and transferrin saturation values in nonwhites.

Arthritis↗
PubMed2005

A Canadian multicenter retrospective study evaluating transjugular liver biopsy in patients with congenital bleeding disorders and hepatitis C: is it safe and useful?

Prior to the introduction of virally inactivated clotting factor concentrates, the majority of individuals with congenital bleeding disorders became infected with the hepatitis C virus. Although liver biopsy is valuable in prognosis and guiding antiviral therapy, there is a reluctance to perform biopsies in this population because of the risk of hemorrhage. The purpose of this study was to evaluate the safety of transjugular liver biopsy, and the usefulness of evaluating liver histology in this patient population. Liver histopathology was assessed by the METAVIR index and compared with corrected sinusoidal pressures, platelet counts, and abdominal ultrasonography. Liver biopsy was performed at seven Canadian centers in 65 patients with hemophilia or von Willebrand's disease. Biopsies were done on an outpatient basis, followed by a 4-hr observation period in hospital. Normal hemostasis was maintained during the peribiopsy period, with follow-up doses of factor concentrate self administered by the patient at home. One patient (1.4%) had significant bleeding leading to readmission and red cell transfusion. Liver histology showed 14 patients (22%) had cirrhosis. Ten patients had elevated corrected sinusoidal pressures; 7 of these (70%) had cirrhosis on biopsy, and the other 3 (30%) likely had cirrhosis although histology showed stage 3 fibrosis. This series represents the largest reported experience of transjugular biopsy in individuals with congenital bleeding disorders. We conclude that this procedure can be safely performed on an outpatient basis. The diagnosis of cirrhosis and/or portal hypertension was made in a substantial proportion of individuals (26%), all of whom had asymptomatic liver disease.

Adult↗
PubMed2005

Phenotype variation in C282Y homozygotes for the hemochromatosis gene.

BACKGROUND & AIMS: Typical hemochromatosis patients are homozygous for the C282Y mutation of the HFE gene. However, approximately 50% of women and 20% of men do not have an increase in serum ferritin level. This study assessed factors, genetic and otherwise, that may modify biochemical expression in C282Y homozygotes. METHODS: Hemochromatosis families that each had at least 2 untreated C282Y homozygotes were included. Nonexpressors were defined as having a ferritin level less than 300 microg/L for a male and a ferritin level less than 200 microg/L for a female. A multivariate linear stepwise regression analysis was performed to assess the contribution of sex, age, and the presence of a nonexpressor in the family on serum ferritin level. Heritability calculations were performed using variance component analysis. RESULTS: Fifty-three pedigrees consisting of 148 C282Y homozygotes (92 males, 56 females) were identified. Twenty-nine homozygotes were nonexpressors (19.6%), of which 11 of 29 were male (37.9%) (P=.0054). Based on multivariate analysis, highly significant associations with increased ferritin levels in C282Y homozygotes were male sex (P=.00005), increasing age (P=.009), and absence of a nonexpressor in the family (P=.01). Variance component modeling using age, sex, and C282Y genotype as covariates in 39 pedigrees (n=296) showed a residual heritability for serum ferritin of .35+/-.10 (P<.001). CONCLUSIONS: These findings suggest that male sex is the major clinical factor associated with an increased serum ferritin level in hemochromatosis. In addition, these results support the hypothesis that other genes contribute to the variance in serum ferritin concentration among C282Y homozygotes.

Adolescent↗
PubMed2005

Glucose-induced regulation of novel iron transporters in vascular endothelial cell dysfunction.

Increased iron indices have been associated with the development of diabetes and its complications. In the present study, we have investigated the glucose-induced alteration of iron transporters, divalent metal transporter-1 (DMT-1), iron regulated transporter protein-1 (IREG-1), and transferrin receptor (TfR), in endothelial cell iron accumulation and oxidative stress. Cells were exposed to high glucose levels and subjected to gene expression, protein expression, iron measurement and assessment of oxidative stress. Our results show, for the first time, expression of DMT-1 and IREG-1 in vascular endothelial cells. Our data further indicates upregulation of DMT-1 and IREG-1 mRNA and protein in response to high levels of glucose. TfR, however, exhibited a modest decrease in response to high levels of glucose. Increased expression of DMT-1 and IREG-1 was associated with iron accumulation and oxidative stress. Furthermore, our results show differential expression of iron transporters with treatment of high glucose-exposed cells with two different iron chelators. In conclusion, our study suggests that glucose-induced alteration of iron transporters may arbitrate iron accumulation and oxidative stress in endothelial cells.

Biological Transport↗
PubMed2005

Initial screening transferrin saturation values, serum ferritin concentrations, and HFE genotypes in whites and blacks in the Hemochromatosis and Iron Overload Screening Study.

We compared initial screening data of 44,082 white and 27,124 black Hemochromatosis and Iron Overload Screening (HEIRS) Study participants. Each underwent serum transferrin saturation (TfSat) and ferritin (SF) measurements without regard to fasting, and HFE C282Y and H63D genotyping. Elevated measurements were defined as: TfSat more than 50% (men), more than 45% (women); and SF more than 300 ng/ml (men), more than 200 ng/ml (women). Mean TfSat and percentages of participants with elevated TfSat were significantly greater in whites than in blacks. Mean SF and percentages of participants with elevated SF were significantly greater in blacks than in whites. TfSat and SF varied by gender and age in whites and blacks. Prevalences of genotypes that included either C282Y or H63D were significantly greater in whites than in blacks. The prevalence of elevated TfSat and SF plus genotypes C282Y/C282Y, C282Y/H63D, or H63D/H63D was 0.006 in whites and 0.0003 in blacks. Among whites with HFE C282Y homozygosity, 76.8% of men and 46.9% of women had elevated TfSat and SF values. Three black participants had HFE C282Y homozygosity; one had elevated TfSat and SF values. Possible explanations for differences in TfSat and SF in whites and blacks and pertinence to the detection of hemochromatosis, iron overload, and other disorders with similar phenotypes are discussed.

Adult↗
PubMed2004

Screening in liver disease: report of an AASLD clinical workshop.

This report summarizes an AASLD Clinical Workshop that was presented at Digestive Diseases Week 2003 on screening in liver diseases. As newer diagnostic tests become available, many liver diseases and complications of liver disease can be detected at an early asymptomatic stage. In many cases, early detection can lead to earlier treatment and an improved outcome. However, screening for liver diseases in asymptomatic persons has the potential for adverse consequences, including discrimination and stigmatization. The cost of screening programs is significant, and access to screening tests varies in different countries. Future screening programs require careful planning and implementation to balance the benefits, risks, and cost-effectiveness. This review outlines the concepts of screening and their application to a broad range of liver diseases.

Cost-Benefit Analysis↗