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Jason A Dominitz

Publications and source records attributed to Jason A Dominitz.

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↗
PubMed2007

Surgeon and hospital characteristics as predictors of major adverse outcomes following colon cancer surgery: understanding the volume-outcome relationship.

HYPOTHESIS: Although numerous studies have demonstrated an association between surgical volume and improved outcome in cancer surgery, the specific structures and mechanisms of care that are associated with volume and lead to improved outcomes remain poorly defined. We hypothesize that there are modifiable surgeon and hospital characteristics that explain observed volume-outcome relationships. DESIGN: Retrospective cohort study. SETTING: Surveillance, Epidemiology, and End Results cancer registry areas. PATIENTS: Patients aged 66 years and older, diagnosed and surgically treated for stage I, II, or III colon cancer between 1992 and 1996 (n = 22 672). MAIN OUTCOME MEASURES: Thirty-day postoperative mortality and 30-day postoperative procedural interventions, including reoperation and image-guided percutaneous procedures. RESULTS: Surgeon volume, but not hospital volume, is a significant predictor of postoperative procedural intervention (adjusted odds ratio for very high-volume surgeons vs low-volume surgeons, 0.79; 95% confidence interval, 0.64-0.98). In the unadjusted analyses, high hospital volume (odds ratio, 0.67; 95% confidence interval, 0.56-0.81) and very high hospital volume (odds ratio, 0.65; 95% confidence interval, 0.54-0.79) is associated with lower postoperative mortality. Postoperative procedural intervention is not a significant mediator of the relationship between hospital volume and mortality. A single variable-the presence of sophisticated clinical services-was the most important explanatory variable underlying the relationship between hospital volume and mortality. CONCLUSIONS: Very high surgeon volume is associated with a reduction in surgical complications. However, the association between increasing hospital volume and postoperative mortality appears to derive mainly from a full spectrum of clinical services that may facilitate the prompt recognition and treatment of complications.

Adenocarcinoma↗
PubMed2007

Reoperation as a quality indicator in colorectal surgery: a population-based analysis.

OBJECTIVE: To describe unplanned procedures following colorectal cancer surgery that might be used as intermediate outcome measures, and to determine their association with mortality and length of stay. SUMMARY BACKGROUND: Variation in the quality of surgical care, especially for common illnesses like colorectal cancer, has received increasing attention. Nonfatal complications resulting in procedural interventions are likely to play a role in poor outcomes but have not been well explored. METHODS: Cohort analysis of 26,638 stage I to III colorectal cancer patients in the 1992 to 1996 SEER-Medicare database. INDEPENDENT VARIABLES: sociodemographics, tumor characteristics, comorbidity, and acuity. PRIMARY OUTCOME: postoperative procedural intervention. ANALYSIS: Logistic regression identified patient characteristics predicting postoperative procedures and the adjusted risk of 30-day mortality and prolonged hospitalization among patients with postoperative procedures. RESULTS: A total of 5.8% of patients required postoperative intervention. Patient characteristics had little impact on the frequency of postoperative procedures, except for acute medical conditions, including bowel perforation (relative risk [RR] = 3.0, 95% confidence interval [CI] = 2.5-3.6), obstruction (RR = 1.6; 95% CI = 1.4-1.8), and emergent admission (RR = 1.3; 95% CI = 1.1-1.4). After a postoperative procedure, patients were more likely to experience early mortality (RR = 2.4; 95% CI = 2.1-2.9) and prolonged hospitalization (RR = 2.2; 95% CI = 2.1-2.4). The most common interventions were performed for abdominal infection (31.7%; RR mortality = 2.9; 95% CI = 2.3-3.7), wound complications (21.1%; RR mortality = 0.7; 95% CI = 0.4-1.3), and organ injury (18.7%; RR mortality = 1.6; 95% CI = 1.1-2.3). CONCLUSIONS: Postoperative complications requiring additional procedures among colorectal cancer patients correlate with established measures of surgical quality. Prospective tracking of postoperative procedures as complication markers may facilitate outcome studies and quality improvement programs.

Aged↗
PubMed2006

Completion of therapy by Medicare patients with stage III colon cancer.

BACKGROUND: Certain factors, such as race or age, are known to be associated with variation in initiation of adjuvant chemotherapy for stage III colon cancer, but little is known about what factors are associated with completion of adjuvant therapy. To determine whether predictors of initiation also predict completion, we analyzed Surveillance, Epidemiology, and End Results (SEER) program data linked to Medicare claims. We investigated mortality as a means to testing the validity of the completion measure that we created. METHODS: We studied 3193 stage III colon cancer patients whose diagnosis was recorded in 1992-1996 SEER program data linked to 1991-1998 Medicare claims and who initiated adjuvant chemotherapy after colon cancer resection. We defined a measure of adjuvant chemotherapy completion as one chemotherapy administration claim in a month. We tested the validity of the created measure and its relation to 3-year cancer mortality adjusted for demographic, clinical, and environmental variables. We explored the association of patient characteristics and treating physician characteristics with chemotherapy completion by use of multivariable logistic regression modeling. RESULTS: Of the 3193 patients, 2497 (78.2%) completed the course. Risk of cancer-related mortality was statistically significantly lower among those completing chemotherapy (relative risk = 0.79, 95% confidence interval = 0.69 to 0.89) than those with no adjuvant therapy. Patients who were female, widowed, increasingly elderly, rehospitalized, and living in certain regions were less likely to complete adjuvant chemotherapy than other patients. Race and other clinical, environmental, and physician characteristics were not associated with completion of therapy. CONCLUSIONS: Factors associated with incomplete adjuvant chemotherapy may represent physical frailty, treatment complications, and lack of social and psychological support. Interventions to mitigate these influences are a logical next step toward increasing chemotherapy completion rates.

Aged↗
PubMed2006

Complications and antireflux medication use after antireflux surgery.

BACKGROUND & AIMS: Although antireflux surgery is increasingly common, few studies have assessed the associated complications and health care use after surgery. The aim of this study was to estimate postoperative complications and continued use of antireflux medications and to identify predictors of complications. METHODS: Through a review of the Department of Veterans Affairs administrative databases, all patients undergoing antireflux surgery from October 1, 1990, through January 29, 2001, were identified. Of 3367 patients identified, 222 were excluded as a result of a diagnosis of esophageal cancer, achalasia, or because there was no diagnosis related to gastroesophageal reflux disease. Medication use was determined for 2406 patients who had a minimum of 1 year of follow-up, including 1 or more outpatient visits at least 6 months after surgery and during the time when national pharmacy records were available. RESULTS: Dysphagia was recorded in 19.4%, dilation was performed in 6.4%, and a repeat antireflux surgery was performed in 2.3%. The surgical mortality rate was .8%. Prescriptions were dispensed repeatedly for H2 receptor antagonists in 23.8%, proton pump inhibitors in 34.3%, and promotility agents in 9.2% of patients. Overall, 49.8% of patients received at least 3 prescriptions for one of these medications. CONCLUSIONS: A moderate proportion of patients undergoing antireflux surgeries experienced complications and approximately 50% of patients received multiple prescriptions for antireflux medications at a median of 5 years of follow-up evaluation. Therefore, before surgery is performed, patients considering surgery should be counseled fully about the risk for complications and the likelihood of continued antireflux medication use.

Adult↗
PubMed2006

Risk stratification for colon neoplasia: screening strategies using colonoscopy and computerized tomographic colonography.

BACKGROUND & AIMS: We developed a risk index to identify low-risk patients who may be screened for colorectal cancer with computerized tomographic colonography (CTC) instead of colonoscopy. METHODS: Asymptomatic persons aged 50 years or older who had undergone screening colonoscopy were randomized retrospectively to derivation (n = 1512) and validation (n = 1493) subgroups. We developed a risk index (based on age, sex, and family history) from the derivation group. The expected results of 3 screening strategies--universal colonoscopy, universal CTC, and a stratified strategy of colonoscopy for high-risk and CTC for low-risk patients--were then compared. Outcomes for the 3 strategies were extrapolated from the known colonic findings in each patient, using sensitivity/specificity values for CTC from the medical literature. Results were validated in the validation subgroup. RESULTS: In the derivation subgroup, universal colonoscopy detected 94% of advanced neoplasia and universal CTC detected only 70% and resulted in the largest total number of procedures and number of patients undergoing both procedures. The stratified strategy detected 92% of advanced neoplasia, requiring colonoscopy in 68% and CTC in 36% of patients, with only 4% having to undergo both procedures. In the validation subgroup, universal colonoscopy detected 94% and universal CTC detected 71% of advanced neoplasia, whereas the stratified strategy detected 89%, requiring colonoscopy in 64% and CTC in 40%. Unlike universal CTC, the stratified strategy was independent of assumptions for CTC sensitivity, specificity, and threshold for colonoscopy. CONCLUSIONS: The stratified strategy based on our risk index may optimize the yield of colonoscopic resources and reduce the number of patients undergoing colonoscopy.

Colonic Neoplasms↗
PubMed2005

Explaining black-white differences in receipt of recommended colon cancer treatment.

BACKGROUND: Black-white disparities exist in receipt of recommended medical care, including colorectal cancer treatment. This retrospective cohort study examines the degree to which health systems (e.g., physician, hospital) factors explain black-white disparities in colon cancer care. METHODS: Data from the Surveillance, Epidemiology, and End Results program; Medicare claims; the American Medical Association Masterfile; and hospital surveys were linked to examine chemotherapy receipt after stage III colon cancer resection among 5294 elderly (> or = 66 years of age) black and white Medicare-insured patients. Logistic regression analysis was used to identify factors associated with black-white differences in chemotherapy use. All statistical tests were two-sided. RESULTS: Black and white patients were equally likely to consult with a medical oncologist, but among patients who had such a consultation, black patients were less likely than white patients (59.3% versus 70.4%, difference = 10.9%, 95% confidence interval [CI] = 5.1% to 16.4%, P < .001) to receive chemotherapy. This black-white disparity was highest among patients aged 66-70 years (black patients 65.7%, white patients 86.3%, difference = 20.6%, 95% CI = 10.7% to 30.4%, P < .001) and decreased with age. The disparity among patients aged 66-70 years also remained statistically significant in the regression analysis. Overall, patient, physician, hospital, and environmental factors accounted for approximately 50% of the disparity in chemotherapy receipt among patients aged 66-70 years; surgical length of stay and neighborhood socioeconomic status accounted for approximately 27% of the disparity in this age group, and health systems factors accounted for 12%. CONCLUSIONS: Black and white Medicare-insured colon cancer patients have an equal opportunity to learn about adjuvant chemotherapy from a medical oncologist but do not receive chemotherapy equally. Little disparity was explained by health systems; more was explained by illness severity, social support, and environment. Further qualitative research is needed to understand the factors that influence the lower receipt of chemotherapy by black patients.

Black or African American↗
PubMed2005

Elevated prevalence of hepatitis C infection in users of United States veterans medical centers.

Several studies suggest veterans have a higher prevalence of hepatitis C virus infection than nonveterans, possibly because of military exposures. The purpose of this study was to estimate the prevalence of anti-hepatitis C antibody and evaluate factors associated with infection among users of Department of Veterans Affairs medical centers. Using a two-staged cluster sample, 1288 of 3863 randomly selected veterans completed a survey and underwent home-based phlebotomy for serological testing. Administrative and clinical data were used to correct the prevalence estimate for nonparticipation. The prevalence of antihepatitis C antibody among serology participants was 4.0% (95% CI, 2.6%-5.5%). The estimated prevalence in the population of Veterans Affairs medical center users was 5.4% (95% CI, 3.3%-7.5%) after correction for sociodemographic and clinical differences between participants and nonparticipants. Significant predictors of seropositivity included demographic factors, period of military service (e.g., Vietnam era), prior diagnoses, health care use, and lifestyle factors. At least one traditional risk factor (transfusion or intravenous drug use) was reported by 30.2% of all subjects. Among those testing positive for hepatitis C antibody, 78% either had a transfusion or had used injection drugs. Adjusting for injection drug use and nonparticipation, seropositivity was associated with tattoos and incarceration. Military-related exposures were not found to be associated with infection in the adjusted analysis. In conclusion, the prevalence of hepatitis C in these subjects exceeds the estimate from the general US population by more than 2-fold, likely reflecting more exposure to traditional risk factors among these veterans.

Adult↗
PubMed2005

Is central obesity associated with cirrhosis-related death or hospitalization? A population-based, cohort study.

BACKGROUND & AIMS: We aimed to determine the interaction between body fat distribution (central versus peripheral) and increased body mass index (BMI) with regards to the risk of cirrhosis-related death or hospitalization. METHODS: Participants included 11,434 persons aged 25-74 years without evidence of cirrhosis at entry into the study or during the first 5 years of follow-up who were subsequently followed for a mean of 12.9 years as part of the first National Health and Nutrition Examination Survey. Participants were categorized into "normal-weight" (BMI < 25 kg/m 2 , N = 5750), "overweight" (BMI 25 to < 30 kg/m 2 , N = 3770), and "obese" (BMI > or = 30 kg/m 2 , N = 1914). The subscapular to triceps skinfold thickness ratio (SFR) was used to categorize body fat distribution into central (SFR > 1, N = 5211) and peripheral (SFR < or = 1, N = 6223). RESULTS: Cirrhosis resulted in death or hospitalization of 88 participants during 149,888 person-years of follow-up (59/100,000 person-years). Among persons with a central body fat distribution, cirrhosis-related deaths or hospitalizations were more common in obese persons (115/100,000 person-years, adjusted hazard ratio 2.2, 95% confidence interval [CI] 1.1-4.6) and in overweight persons (94/100,000 person-years, adjusted hazard ratio 1.5, 95% CI 0.8-3.0) compared to normal-weight persons (59/100,000 person-years). However, among persons with a peripheral fat distribution, there was no association between obesity (adjusted hazard ratio 0.7, 95% CI 0.3-1.6) or overweight (adjusted hazard ratio 0.8, 95% CI 0.2-2.8) and cirrhosis-related death or hospitalization. CONCLUSIONS: The risk of cirrhosis-related death or hospitalization appears to be increased in the presence of cirrhosis, but only among persons with a central fat distribution. The excess risk associated with central obesity might be related to insulin resistance and hepatic steatosis.

Adult↗
PubMed2005

Cost effectiveness of testing strategies for chronic hepatitis C.

OBJECTIVE: This paper compares nine strategies for determining hepatitis C antibody and viral status. They combine two tests for antibodies (enzyme immunoassays (EIA), recombinant immunoblot assays (RIBA)) and one for viremia (reverse transcription polymerase chain reaction (PCR)). Using optical density to divide EIA results into three categories (high positive, low positive, negative) was also considered. METHODS: Decision analysis compared strategies on cost as well as sensitivity and specificity with regard to antibody and viral status. Parameters in the decision tree included antibody prevalence, proportion viremic, sensitivity, specificity, and cost of individual tests. RESULTS: The two best strategies are EIA followed by PCR (EIA-->PCR); and EIA with three levels of optical density (EIA-OD), followed by RIBA for EIA-OD low positives, and then PCR for all positives (EIA-OD-->RIBA-->PCR). EIA-->PCR has equal viral sensitivity, slightly lower cost, slightly higher antibody sensitivity, but lower antibody specificity compared to EIA-OD-->RIBA-->PCR. The cost per false antibody positive avoided using EIA-OD-->RIBA-->PCR rather than EIA-->PCR is $36 when prevalence is 5%, and $193 when prevalence is 50%. Using EIA-OD-->RIBA-->PCR rather than EIA-->PCR results in 112 false antibody positives avoided for every true antibody positive missed when prevalence is 5%; this ratio is 18:1 when prevalence is 25%; and 6:1 when prevalence is 50%. CONCLUSIONS: EIA-OD-->RIBA-->PCR is the best choice when prevalence in the tested group is below 20%. As prevalence increases, the choice of EIA-OD-->RIBA-->PCR versus EIA-->PCR will depend on the relative importance of avoiding false antibody positives versus missing true antibody positives. Our analysis makes explicit the magnitude of this trade-off.

Cost-Benefit Analysis↗
PubMed2005

Risk factors for colorectal cancer in relation to number and size of aberrant crypt foci in humans.

Several characteristics of aberrant crypt foci (ACF) suggest that they are precursors of colorectal cancer, but the factors that promote or inhibit their growth are largely unknown. We conducted a pilot study to explore whether factors associated with risk of colorectal cancer are also associated with number or size of rectal ACF. Thirty-two U.S. veterans, ages 50 to 80 years, were recruited to undergo magnifying chromoendoscopy for imaging of rectal ACF and colonoscopy for identification of polyps or cancer. Participants completed a questionnaire on cigarette smoking, use of nonsteroidal anti-inflammatory drugs (NSAIDs), and family history of colorectal cancer. Fisher's exact test was used to assess the statistical significance of associations between colorectal cancer risk factors and characteristics of ACF. Cochran-Mantel-Haenszel statistics and polytomous regression were used to test the significance of associations adjusted for age. Participants with a history of adenoma had more ACF than those without (age-adjusted P = 0.02), but the numbers in the two groups overlapped markedly. Older participants had more (P = 0.06) and larger (P = 0.009) ACF than younger participants. No associations were identified between either ACF number or size and cigarette smoking, use of NSAIDs, or family history of colorectal cancer. These findings suggest that persons with adenomas have somewhat more rectal ACF than persons without, and that older age is a risk factor for ACF growth. Future research should be directed toward developing techniques to identify ACF that are likely to progress to cancer and the modifiable factors that promote or inhibit such progression.

Adenoma↗
PubMed2004

Association of interferon-alpha-induced depression and improved treatment response in patients with hepatitis C.

Thirty-nine patients with hepatitis C viral infection on interferon-alpha (IFN-alpha) therapy were monitored weekly using the Beck Depression Inventory (BDI). Thirteen of thirty-nine patients (33%) developed IFN-alpha-induced major depressive disorder (MDD). During the course of IFN-alpha therapy, patients who became depressed were treated with citalopram, a selective serotonin reuptake inhibitor (SSRI) antidepressant. Results indicated that: (1) IFN-alpha response rates were significantly higher in those patients who developed IFN-alpha-induced MDD than in those who did not (end-of-treatment response (ETR) rates: 61.5% versus 26.9% and sustained viral response (SVR) rates: 38.5% versus 11.5%), (2) male patients with ETR to IFN-alpha therapy were, on average, approximately 33 pounds lighter in body weight than male patients who did not respond, and (3) gender, race, past history of MDD, and past history of substance abuse were not significantly associated with ETR. In conclusion, our findings suggest that IFN-alpha-induced MDD may be a predictor of a positive response to IFN-alpha therapy, or an indication of optimal dosing.

Adult↗
PubMed2004

The effect of alcohol consumption on the prevalence of iron overload, iron deficiency, and iron deficiency anemia.

BACKGROUND & AIMS: Our aim was to investigate the relationship between alcohol consumption and iron overload, iron deficiency, or iron deficiency anemia in the U.S. population. METHODS: Adult participants of the Third National Health and Nutrition Examination Survey who did not consume alcohol (n = 8839) were compared with participants who consumed < or =1 (n = 4976), >1 to < or =2 (n = 1153), or >2 (n = 915) alcoholic drinks/day during the preceding 12 months. We examined the following markers of iron overload: elevated serum transferrin-iron saturation (TS) level (>45%, >50%, and >60%), elevated serum ferritin level (>300, >400, >500, and >600 ng/mL), and combinations of both elevated serum TS and ferritin levels. Iron deficiency was defined as the presence of at least 2 of the following: serum ferritin level <12 ng/mL, serum TS level <15%, and erythrocyte protoporphyrin level >1.24 micromol/L. Iron deficiency anemia was defined as the presence of both iron deficiency and anemia. RESULTS: Compared with nondrinkers, the prevalence of all markers of iron overload was significantly elevated among those who consumed >2 alcoholic drinks/day after adjusting for potential confounders. Consumption of any amount of alcohol was associated with a 40% reduction in the risk of iron deficiency anemia. CONCLUSIONS: Consumption of up to 2 alcoholic drinks/day seems to be associated with reduced risk of iron deficiency and iron deficiency anemia without a concomitant increase in the risk of iron overload. Consumption of >2 alcoholic drinks/day is associated with a significant elevation in the risk of iron overload.

Adolescent↗
PubMed2004

CT colonoscopy.

Explore the source record for details and available documents.

Colonic Neoplasms↗
PubMed2004

Hepatitis C tested prevalence and comorbidities among veterans in the US Northwest.

GOALS: (1) Investigate the epidemiology of hepatitis C virus infection among patients seen in the Veterans Administration Northwest Network; (2) examine time trends in testing practices and results; and (3) estimate the prevalence of hepatitis C virus infection among active patients. BACKGROUND: Hepatitis C virus infection causes chronic hepatitis and cirrhosis and is a leading cause of end-stage liver disease. Hepatitis C virus antibodies are estimated to be present in 1.8% of the US population, but reports of its prevalence among US veterans range from 1.7 to 35%. STUDY: Retrospective review of computerized medical records of veterans tested for hepatitis C from October 1994 through December 2000 (n = 37,938) at 8 Northwest Veterans Administration Medical Centers. RESULTS: Among tested veterans, 8230 (21.7%) had evidence of hepatitis C virus infection. The number of patients tested increased annually from 2335 to 18,191, while the proportion with first-time positive hepatitis C test results decreased from 35 to 10%. This drop in tested prevalence was associated with a shift away from testing individuals at highest risk--those with positive hepatitis B serostatus, repeatedly elevated alanine transaminase levels, and drug use disorder diagnoses. We estimate that 11.4% of the Northwest Network veteran users are hepatitis C virus seropositive, with a lower bound of 4.0% and upper bound of 19.5%. CONCLUSIONS: Although estimates of hepatitis C virus infection rates among veteran users of the Veterans Administration system remain higher than those for the general population, changes in testing practice make generalizations from earlier studies hazardous.

Adult↗