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Noel S Weiss

Publications and source records attributed to Noel S Weiss.

At least 19 recordsLinked to original sources
PubMed2026

Radiology considerations for the PREMIUM study: a multicenter randomized controlled trial of abbreviated MRI versus ultrasound for liver cancer screening in cirrhosis.

This paper describes the rationale and radiology considerations in the implementation of the Preventing Liver Cancer Mortality through Imaging with Ultrasound versus MRI (PREMIUM) study. PREMIUM is a multicenter, randomized controlled trial sponsored by the Department of Veterans Affairs comparing dynamic contrast-enhanced (DCE) abbreviated MRI (aMRI) plus serum AFP versus ultrasound (US) plus serum AFP for hepatocellular carcinoma (HCC) screening in patients with cirrhosis. PREMIUM aims to randomize 4,700 participants across over 47 Veterans Affairs Medical Centers to semiannual surveillance for up to eight years, with HCC-related mortality as the primary endpoint. To date, 35 sites have been activated with 1,085 patients randomized. To ensure uniform implementation and reporting of per-protocol screening, the PREMIUM Radiology Workgroup developed standardized imaging protocols, structured LI-RADS-based reporting templates, and a centralized training program for radiologists and technologists. They also perform ongoing quality control on both scans and reports. The aMRI protocols utilize multiphasic post-contrast imaging to allow LI-RADS scoring. A non-contrast-enhanced aMRI protocol is available for participants who develop renal impairment or contrast allergy during the study. US protocols conform to US LI-RADS standards. Structured reporting promotes consistency in documentation of findings, visualization scores, and follow-up recommendations. A centralized Image Repository was established, incorporating advanced de-identification methods to remove metadata and pixel-embedded protected health information from imaging files. More than 20,000 curated liver MRI and US exams are anticipated, supporting both trial outcomes and future radiomics and artificial intelligence research. PREMIUM aims to determine whether screening for HCC with a DCE aMRI protocol reduces HCC-related mortality and also facilitates ancillary studies utilizing the Image Repository.

Abbreviated MRI↗
PubMed2003

Polymorphic markers in the 5alpha-reductase type II gene and the incidence of prostate cancer.

In the prostate, the enzyme encoded by the SRD5A2 gene (5alpha-reductase) converts testosterone to dihydrotestosterone, a potent androgen that has been hypothesized to play a role in the genesis of prostate cancer. Several polymorphisms have been identified in the SRD5A2 gene, including a valine-to-leucine substitution (V89L) at codon 89, a variable number of TA dinucleotide repeats and a missense substitution at codon 49 resulting in an amino acid substitution of alanine with threonine (A49T). To investigate the influence of these polymorphisms on prostate cancer risk, we conducted a case-control study nested within the Beta-Carotene and Retinol Efficacy Trial. Genotypes were determined by PCR-based capillary electrophoresis using genomic DNA isolated from 300 cases and 300 controls matched on the basis of race, age at enrollment (within 5 years), enrollment study center and year of randomization. There was no association between V89L genotypes and prostate cancer risk. The age- and race-adjusted odds ratio (OR) associated with the VL and LL genotypes were 1.06 (95% confidence interval (CI) = 0.75-1.49) and 0.99 (95% CI = 0.57-1.73), respectively, as compared to the VV genotype. The age- and race-adjusted odds ratio for men having 1 TA(9) or TA(18) allele was 0.98 (95% CI = 0.64-1.48) when compared to men without TA repeats. The corresponding odds ratio for men without the TA(0) alleles was 0.68 (95% CI = 0.21-2.19). The age- and race-adjusted odds ratio associated with having at least 1 T allele at codon 49 was 1.11 (95% CI = 0.58-2.11), as compared to the AA genotype. Our results do not support the hypothesis that the V89L and A49T polymorphisms in the SRD5A2 gene are related to the risk of prostate cancer, but are compatible with the suggestion from earlier studies that men who are homozygous for the TA(9) or (18) alleles and men who have the TA(9)/TA(18) genotype are at a modestly reduced risk.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2003

Relationship between long durations and different regimens of hormone therapy and risk of breast cancer.

CONTEXT: Women using combined estrogen and progestin hormone replacement therapy (CHRT) have an increased risk of breast cancer; however, data on use for long durations and on risk associated with patterns of use are lacking. OBJECTIVE: To evaluate relationships between durations and patterns of CHRT use and risk of breast cancer by histological type and hormone receptor status. DESIGN: Population-based case-control study. SETTING: Three counties in western Washington State. PARTICIPANTS: Nine hundred seventy-five women 65-79 years of age diagnosed with invasive breast cancer from April 1, 1997, through May 31, 1999 (histology: 196 lobular cases, 656 ductal cases, 114 cases with other histological type, and 9 cases with an unspecified histological type; estrogen receptor (ER)/progesterone receptor (PR) status: 646 ER+/PR+ cases, 147 ER+/PR- cases, and 101 ER-/PR- cases [6 ER-/PR+ cases and 75 cases with unknown ER/PR status were not included in the analyses herein]) and 1007 population controls. MAIN OUTCOME MEASURES: Risks of invasive lobular, ductal, ER+/PR+, ER+/PR-, and ER-/PR- breast carcinomas. RESULTS: Women using unopposed estrogen replacement therapy (ERT) (exclusive ERT use), even for 25 years or longer, had no appreciable increase in risk of breast cancer, although the associated odds ratios were not inconsistent with a possible small effect. Ever users of CHRT (includes CHRT users who also had used ERT) had a 1.7-fold (95% confidence interval [CI], 1.3-2.2) increased risk of breast cancer, including a 2.7-fold (95% CI, 1.7-4.3) increased risk of invasive lobular carcinoma, a 1.5-fold (95% CI, 1.1-2.0) increased risk of invasive ductal carcinoma, and a 2.0-fold (95% CI, 1.5-2.7) increased risk of ER+/PR+ breast cancers. The increase in risk was greatest in those using CHRT for longer durations (users for 5-14.9 years and >or=15 years had 1.5-fold [95% CI, 1.0-2.3] and 1.6-fold [95% CI, 1.0-2.6] increases in risk of invasive ductal carcinoma, respectively, and 3.7-fold [95% CI, 2.0-6.6] and 2.6-fold [95% CI, 1.3-5.3] increases in risk of invasive lobular carcinoma, respectively. Associations of similar magnitudes were seen among users of both sequential and continuous CHRT. Risks of ER+/PR- and ER-/PR- tumors were not increased by use of any form of hormone replacement therapy; however, small numbers of these tumors limited power to detect possible associations. CONCLUSION: These data suggest that use of CHRT is associated with an increased risk of breast cancer, particularly invasive lobular tumors, whether the progestin component was taken in a sequential or in a continuous manner.

Aged↗
PubMed2003

Adjusting for screening history in epidemiologic studies of cancer: why, when, and how to do it.

In epidemiologic studies of cancer, differences between exposed and nonexposed persons with regard to a history of cancer screening during the time the malignancy (or an antecedent lesion) typically is present prior to diagnosis can be a source of confounding if one of the following conditions is present: (1) the screening modality identifies premalignant changes whose treatment has the potential to prevent the cancer from developing; or (2) the number of cases included in the study would have been smaller but for the presence of screening. These situations occur commonly, arguing that consideration be given to screening history in the design (with attention to distinguishing true screening tests from those administered to persons with signs or symptoms of cancer) and analysis of epidemiologic studies of those cancers for which screening modalities are in use in the study population.

Bias↗
PubMed2003

Health outcomes associated with various antihypertensive therapies used as first-line agents: a network meta-analysis.

CONTEXT: Establishing relative benefit or harm from specific antihypertensive agents is limited by the complex array of studies that compare treatments. Network meta-analysis combines direct and indirect evidence to better define risk or benefit. OBJECTIVE: To summarize the available clinical trial evidence concerning the safety and efficacy of various antihypertensive therapies used as first-line agents and evaluated in terms of major cardiovascular disease end points and all-cause mortality. DATA SOURCES AND STUDY SELECTION: We used previous meta-analyses, MEDLINE searches, and journal reviews from January 1995 through December 2002. We identified long-term randomized controlled trials that assessed major cardiovascular disease end points as an outcome. Eligible studies included both those with placebo-treated or untreated controls and those with actively treated controls. DATA EXTRACTION: Network meta-analysis was used to combine direct within-trial between-drug comparisons with indirect evidence from the other trials. The indirect comparisons, which preserve the within-trial randomized findings, were constructed from trials that had one treatment in common. DATA SYNTHESIS: Data were combined from 42 clinical trials that included 192 478 patients randomized to 7 major treatment strategies, including placebo. For all outcomes, low-dose diuretics were superior to placebo: coronary heart disease (CHD; RR, 0.79; 95% confidence interval [CI], 0.69-0.92); congestive heart failure (CHF; RR, 0.51; 95% CI, 0.42-0.62); stroke (RR, 0.71; 0.63-0.81); cardiovascular disease events (RR, 0.76; 95% CI, 0.69-0.83); cardiovascular disease mortality (RR, 0.81; 95% CI, 0.73-0.92); and total mortality (RR, 0.90; 95% CI, 0.84-0.96). None of the first-line treatment strategies-beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, calcium channel blockers (CCBs), alpha-blockers, and angiotensin receptor blockers-was significantly better than low-dose diuretics for any outcome. Compared with CCBs, low-dose diuretics were associated with reduced risks of cardiovascular disease events (RR, 0.94; 95% CI, 0.89-1.00) and CHF (RR, 0.74; 95% CI, 0.67-0.81). Compared with ACE inhibitors, low-dose diuretics were associated with reduced risks of CHF (RR, 0.88; 95% CI, 0.80-0.96), cardiovascular disease events (RR, 0.94; 95% CI, 0.89-1.00), and stroke (RR, 0.86; 0.77-0.97). Compared with beta-blockers, low-dose diuretics were associated with a reduced risk of cardiovascular disease events (RR, 0.89; 95% CI, 0.80-0.98). Compared with alpha-blockers, low-dose diuretics were associated with reduced risks of CHF (RR, 0.51; 95% CI, 0.43-0.60) and cardiovascular disease events (RR, 0.84; 95% CI, 0.75-0.93). Blood pressure changes were similar between comparison treatments. CONCLUSIONS: Low-dose diuretics are the most effective first-line treatment for preventing the occurrence of cardiovascular disease morbidity and mortality. Clinical practice and treatment guidelines should reflect this evidence, and future trials should use low-dose diuretics as the standard for clinically useful comparisons.

Humans↗
PubMed2003

Matched-pair cohort methods in traffic crash research.

Standard analysis of matched-pair cohort data requires information only from pairs in which at least one had the study outcome. This can be useful in traffic fatality studies of characteristics that can vary among vehicle occupants, such as seat belt use, as crash databases often lack information about vehicles in which all survived. However, matching crash victims who were in the same vehicle does not necessarily eliminate confounding by vehicle or crash related factors, because the matched occupants must be in different seat positions. This paper reviews three methods for estimating relative risks in matched-pair crash data. The first, Mantel-Haenszel stratified methods, may produce biased estimates if seat position is associated with the outcome. The second, the double-pair comparison method, was designed to deal with confounding by seat position. If the effects of seat position vary according to some vehicle or crash characteristic which is associated with the study exposure, adjustment for this characteristic may be needed to produce unbiased estimates. Third, conditional Poisson regression and Cox proportional hazards regression can produce unbiased estimates, but may require model interaction terms between seat position and vehicle or crash characteristics. This paper reviews some of the strengths and limitations of each of these methods, and illustrates their use in simulated and real crash data.

Accidents, Traffic↗
PubMed2003

Glucose screening and the risk of complications in Type 2 diabetes mellitus.

It is unknown whether glucose screening for Type 2 diabetes mellitus (DM2) reduces the risk of diabetic complications. We conducted a case-control study using 303 cases with DM2 and at least one symptomatic microvascular diabetic complication, matched 1:1 to control subjects. All subjects' blood glucose tests for the decade before the first clinical suspicion of DM2 were categorized as screening or not based on the presence of symptoms suggestive of DM2. Approximately 90% of case subjects and control subjects had been screened for diabetes. After adjusting for multiple covariates in a logistic regression model, the odds ratio of developing a complication associated with screening was 0.87 (95% confidence interval 0.38-1.98), suggesting that screening may be associated with a modest reduction in the risk of certain diabetic complications. However, the confidence limits were wide and consistent with no true benefit. Further studies are needed to establish whether the small reduction we observed is genuine.

Blood Glucose↗
PubMed2003

An exploration of the periodontitis-cancer association.

PURPOSE: Periodontitis has been linked to the occurrence of various systemic diseases. The goal of this study was to explore the periodontitis-cancer association in the NHANES I Epidemiologic Follow-up Study. METHODS: Data were available on 11,328 adults, age 25 to 74 years, who were diagnosed as dentate individuals with either periodontitis (n = 2092), gingivitis (n = 2603), a healthy periodontium (n = 2,671), or as individuals without teeth (edentulous n = 3,962) at the beginning of the follow-up. The main outcome measure was fatal cancer, as ascertained from death certificates. RESULTS: Compared with individuals with a healthy periodontium, fatal cancer occurrence was positively associated with periodontitis at baseline (age and gender adjusted odds ratio = 1.55, 95% confidence interval: 1.25-1.92). Of the different cancer types, lung cancer demonstrated the strongest association. After adjustment for known risk factors for lung cancer, the magnitude of the association between periodontitis and lung cancer ranged between 1.48 (95% confidence interval: 0.88-2.50) and 1.73 (95% confidence interval: 1.01-2.97). CONCLUSIONS: Associations between periodontitis and lung cancer mortality can be identified above and beyond adjustment for known risk factors for lung cancer. Despite these apparent unconfounded associations, there are reasons to believe that the periodontitis-cancer associations may be spurious.

Adult↗
PubMed2003

Endometrial cancer in Asian migrants to the United States and their descendants.

OBJECTIVE: The purpose of this study was to determine the extent to which the incidence of endometrial cancer in Chinese, Japanese, and Filipino residents of the United States varies according to country of birth. METHODS: Women 35-74 years diagnosed with endometrial cancer between 1973 and 1986 among residents of the San Francisco/Oakland (CA) metropolitan area, 13 counties of western Washington, and the state of Hawaii were identified by cancer registries serving these populations. From a special tabulation of the 1980 US census, we estimated the size of the population at risk in each of these three areas according to age, race, and country of birth. RESULTS: The annual incidence of primary endometrial cancer was lower among Chinese-American (42.6/100,000) and Japanese-American (25.3/100,000) women born in Asia than among their counterparts who were born in the United States (57.2/100,000 and 51.2/100,000, respectively). No difference in incidence was observed between Filipino women born in Asia (27.4/100,000) and those born in the United States (25.4/100,000). The rate of endometrial cancer among US-born white women (77.0/100,000 women years) exceeded that in any of these Asian-American subgroups. CONCLUSIONS: These findings suggest that some clues to the aetiologies of endometrial cancer may be found in exposures whose prevalence differs between generations of Chinese and Japanese Americans.

Adult↗
PubMed2003

Risk factors for colorectal cancer following breast cancer.

OBJECTIVE: To investigate risk factors for colorectal cancer following breast cancer. METHODS: In this nested case-control study, all women (n = 14,900) with a first primary breast cancer (1978-1992) were identified from the western Washington population-based Surveillance, Epidemiology, and End Results Cancer Registry. Cases (n = 160) developed a second primary colorectal cancer before 1995, at least 6 months after the first cancer diagnosis. Controls (n = 310, matched to the cases on calendar year, age and breast cancer stage) were randomly selected from those who did not develop a second primary cancer and who survived to the case's colorectal cancer diagnosis date. Characteristics of the cases and controls at initial diagnosis were compared using conditional logistic regression. RESULTS: The incidence of colorectal cancer was associated with a family history of breast cancer (v.s. no family history, matched odds ratio (mOR) = 2.1, 95% confidence interval (CI): 1.1-4.1), high body mass index (> or = 30kg/m2 v.s. < 30kg/m2, mOR = 2.2, CI: 1.2-3.9), and lobular breast cancer histology (v.s. ductal, mOR = 2.0, CI: 0.9-4.4). Risk was unrelated to menopausal status, prior hormone replacement therapy and estrogen/progesterone receptor status of the breast tumors. CONCLUSIONS: The risk of developing a second primary colorectal cancer may be elevated among certain subsets of breast cancer patients.

Adult↗
PubMed2003

Racial differences in the relationship between hepatitis C infection and iron stores.

Black race and increased hepatic iron stores predict poor response to interferon treatment for chronic hepatitis C virus (HCV) infection. We tested the hypothesis that these 2 observations are linked by investigating whether HCV-infected African-Americans have increased iron stores relative to uninfected persons. Using data from the third National Health and Nutrition Examination Survey (NHANES III), we determined the risk of having increased iron stores, defined as elevation of both serum ferritin and transferrin-iron saturation (TS), in HCV-RNA-positive blacks (n = 100) and nonblacks (n = 126) relative to HCV-RNA-negative blacks (n = 4,002) and nonblacks (n = 10,943). HCV-positive blacks were 5.4 times (95% CI, 1.2 to 24) more likely to have increased iron stores than HCV-positive nonblacks. The proportion of HCV-positive blacks who had increased iron stores was 16.4% among those with abnormal liver enzymes and 2.8% among those with normal liver enzymes, compared with only 0.6% among HCV-negative blacks. After adjustment for age, alcohol intake, gender, menopausal status, education, body mass index, and poverty index, HCV-positive blacks with abnormal liver enzymes had an elevated risk of having increased iron stores (odds ratio, 17.8; 95% CI, 5.1 to 63). In contrast, among persons of other races, there was a much smaller difference in the proportion of persons with increased iron stores between HCV-positive persons with (3.4%) or without (1.4%) abnormal liver enzymes and HCV-negative persons (0.9%). In conclusion, a greater proportion of blacks than persons of other races respond to HCV infection with an increase in iron stores. This finding may partly explain the reduced response of HCV-positive African-Americans to antiviral treatment.

Adult↗
PubMed2002

Risk of hip fracture among dialysis and renal transplant recipients.

CONTEXT: Renal failure places people at particularly high risk of hip fracture. However, the possible differential impact of dialysis and renal transplantation on this risk is not well understood. OBJECTIVE: To determine if patients who receive kidney transplants are at greater risk of hip fracture compared with those who continue to undergo dialysis. DESIGN, SETTING, AND PARTICIPANTS: Cohort study of 101 039 patients with end-stage renal disease placed on the renal transplant waiting list in the United States between January 1, 1990, and December 31, 1999. MAIN OUTCOME MEASURES: Hip fractures, identified from Medicare claims data. RESULTS: Among the patients included in this analysis, 971 hip fractures were observed during the follow-up period of 314 767 person-years. The incidence rate of hip fracture in patients receiving dialysis was 2.9 per 1000 patients per year compared with 3.3 hip fractures per 1000 patients per year in those who had previously received a renal transplant. Initially, the relative risk (RR) of hip fracture associated with transplantation was 1.34-fold greater when compared with dialysis (adjusted RR, 1.34; 95% confidence interval [CI], 1.12-1.61) but then decreased by 1% per month (adjusted RR, 0.99; 95% CI, 0.98-0.99) until the estimated risk became equal for dialysis and transplant recipients approximately 630 days after transplantation (adjusted RR, 1.00; 95% CI, 0.87-1.15). Among transplant recipients, risk of fracture was relatively higher in persons with a prolonged period of dialysis before transplantation. CONCLUSION: The high risk of hip fracture among dialysis patients is exceeded by that among renal transplant patients during the first 1 to 3 years after transplantation.

Adult↗
PubMed2002

Relationship of uveal and cutaneous malignant melanoma in persons with multiple primary tumors.

Uveal and cutaneous melanomas differ in tumor biology, immunophenotypes and the demographic correlates of their occurrence. As a means to examine the possibility of some shared etiologic factors, we wished to learn if the 2 cancers occurred in the same individual more often than would be expected by chance. Data from the Surveillance, Epidemiology and End Results (SEER) program from 1973-1998 were utilized for this purpose. The number of persons who went on to develop a second melanoma was compared to that expected based on the incidence of each type of melanoma in the general population, after adjusting for age, sex, calendar year and residence. Given an initial cutaneous melanoma, there was a 10-fold increased risk of developing a second cutaneous melanoma (95% confidence interval [CI] = 9.4-10.6). Persons with uveal melanoma went on to develop cutaneous melanoma 4.6 times (95% CI = 2.9-6.8) more often than the population at large. In contrast, persons with cutaneous melanoma were not subsequently diagnosed with uveal melanoma at an appreciably elevated rate (standardized incidence ratio [SIR] = 1.4; 95% CI = 0.5-3.0). While these data offer some support for the hypothesis that uveal and cutaneous melanomas have 1 or more etiologies in common, the lack of symmetry in the pattern of second uveal and second cutaneous melanomas remains unexplained.

Age Factors↗
PubMed2002

Evaluation of human papillomavirus testing in primary screening for cervical abnormalities: comparison of sensitivity, specificity, and frequency of referral.

CONTEXT: Human papillomavirus (HPV) DNA testing of women having Papanicolaou (Pap) smears showing atypical squamous cells of undetermined significance (ASCUS) has clinical usefulness. Whether HPV DNA testing alone is useful in primary screening remains to be determined. OBJECTIVE: To determine the accuracy of HPV DNA testing for detecting cervical intraepithelial neoplasia (CIN) grade 3 or cancer (the criterion standard). DESIGN, SETTING, AND PARTICIPANTS: Between December 1997 and October 2000, 4075 women who attended Planned Parenthood clinics in Washington State were screened simultaneously using thin-layer Pap and HPV DNA testing by a polymerase chain reaction (PCR)-based method and by a liquid-based RNA-DNA hybridization capture with signal amplification assay (signal amplification). Women who were positive for high-risk HPV types, or had Pap results of ASCUS or higher, were considered to have positive screening test results and were referred for colposcopy and biopsy. Additionally, a random sample of women with negative screening test results was referred for colposcopy. Based on individual and combined thin-layer Pap, HPV PCR, and HPV signal amplification test results from the screening and the colposcopy visits, 7 colposcopy triage strategies were defined and evaluated. MAIN OUTCOME MEASURE: Sensitivity and specificity for detecting cervical lesions graded CIN 3 or higher for each of the 7 triage strategies. RESULTS: The estimated prevalence of CIN 3 or higher was 3.2%. The sensitivity (95% confidence interval) of thin-layer Pap (with a result of > or = ASCUS) for identifying women with CIN 3 or higher was only 61.3% (48.5%-70.9%) compared with 88.2% (78.9%-93.8%) for HPV testing by PCR and 90.8% (83.1%-95.8%) by signal amplification. Differences in specificities were also observed: 82.4% (81.8%-83.1%) for thin-layer Pap (with a result of > or = ASCUS), 78.8% (77.9%-79.7%) for PCR, and 72.6% (69.4%-75.0%) for signal amplification. Compared with referral for colposcopy of all women with ASCUS or higher, signal amplification testing of women with ASCUS and referral of those with a positive result was about as sensitive (61.3% vs 60.3%, respectively) and significantly more specific (82.4% vs 88.9%, respectively). The strategy requiring repeat positive PCR tests on 2 visits had a sensitivity of 84.2% (75.3%-91.0%) and a specificity of 86.2% (85.1%-87.3%). All tests were more specific and less sensitive in older (> or = 30 years) vs younger women. CONCLUSIONS: Testing for HPV has higher sensitivity but lower specificity than thin-layer Pap screening. In some settings, particularly where screening intervals are long or haphazard, screening for HPV DNA may be a reasonable alternative to cytology-based screening of reproductive-age women.

Adult↗