Search

Objective: To examine the utility of repeated computed tomography (CT) coronary artery calcium (CAC) testing, we assessed risks of detectable CAC and its cardiovascular consequences in individuals with and without type 2 diabetes ages 45-85 years.Research Design and Methods: We included 5,836 individuals (618 with type 2 diabetes, 2,972 without baseline CAC) from the Multi-Ethnic Study of Atherosclerosis. With logistic and Cox regression we evaluated the impact of type 2 diabetes, diabetes treatment duration, and other predictors on prevalent and incident CAC. We used time-dependent Cox modeling of follow-up data (median 15.9 years) for two repeat CT exams and cardiovascular events to assess the association of CAC at follow-up CT with cardiovascular events.Results: For 45 year olds with type 2 diabetes, the likelihood of CAC at baseline was 23% vs. 17% for those without. Median age at incident CAC was 52.2 vs. 62.3 years for those with and without diabetes, respectively. Each 5 years of diabetes treatment increased the odds and hazard rate of CAC by 19% (95% CI 8-33) and 22% (95% CI 6-41). Male sex, White ethnicity/race, hypertension, hypercholesterolemia, obesity, and low serum creatinine also increased CAC. CAC at follow-up CT independently increased coronary heart disease rates.Conclusions: We estimated cumulative CAC incidence to age 85 years. Patients with type 2 diabetes develop CAC at a younger age than those without diabetes. Because incident CAC is associated with increased coronary heart disease risk, the value of periodic CAC-based risk assessment in type 2 diabetes should be evaluated. [ABSTRACT FROM AUTHOR]

Purpose Hodgkin lymphoma (HL) survivors face an increased risk of treatment-related lung cancer. Screening with low-dose computed tomography (LDCT) may allow detection of early stage, resectable cancers. We developed a Markov decision-analytic and cost-effectiveness model to estimate the merits of annual LDCT screening among HL survivors. Methods and Materials Population databases and HL-specific literature informed key model parameters, including lung cancer rates and stage distribution, cause-specific survival estimates, and utilities. Relative risks accounted for radiation therapy (RT) technique, smoking status (>10 pack-years or current smokers vs not), age at HL diagnosis, time from HL treatment, and excess radiation from LDCTs. LDCT assumptions, including expected stage-shift, false-positive rates, and likely additional workup were derived from the National Lung Screening Trial and preliminary results from an internal phase 2 protocol that performed annual LDCTs in 53 HL survivors. We assumed a 3% discount rate and a willingness-to-pay (WTP) threshold of $50,000 per quality-adjusted life year (QALY). Results Annual LDCT screening was cost effective for all smokers. A male smoker treated with mantle RT at age 25 achieved maximum QALYs by initiating screening 12 years post-HL, with a life expectancy benefit of 2.1 months and an incremental cost of $34,841/QALY. Among nonsmokers, annual screening produced a QALY benefit in some cases, but the incremental cost was not below the WTP threshold for any patient subsets. As age at HL diagnosis increased, earlier initiation of screening improved outcomes. Sensitivity analyses revealed that the model was most sensitive to the lung cancer incidence and mortality rates and expected stage-shift from screening. Conclusions HL survivors are an important high-risk population that may benefit from screening, especially those treated in the past with large radiation fields including mantle or involved-field RT. Screening may be cost effective for all smokers but possibly not for nonsmokers despite a small life expectancy benefit. [ABSTRACT FROM AUTHOR]

Background: Timely, accurate detection of renal artery stenosis is important because this disorder may be a potentially curable cause of hypertension and renal impairment.Objective: To determine the validity of computed tomographic angiography (CTA) and magnetic resonance angiography (MRA) compared with digital subtraction angiography (DSA) for detection of renal artery stenosis.Design: Prospective multicenter comparative study conducted from 1998 to 2001. Two panels of 3 observers judged CTA and MRA image data and were blinded to all other results. Digital subtraction angiography images were evaluated by consensus.Setting: 3 large teaching hospitals and 3 university hospitals in the Netherlands.Patients: 402 hypertensive patients with suspected renal artery stenosis were included. A group of 356 patients who underwent all 3 diagnostic tests was used for analysis.Measurements: Reproducibility was assessed by calculating interobserver agreement. Diagnostic performance was evaluated in terms of sensitivity, specificity, and other diagnostic variables. Atherosclerotic stenoses of 50% or greater and fibromuscular dysplasia were considered clinically relevant.Results: Twenty percent of patients who underwent all 3 tests had clinically relevant renal artery stenosis. Moderate interobserver agreement was found, with kappa values ranging from 0.59 to 0.64 for CTA and 0.40 to 0.51 for MRA. The combined sensitivity and specificity were 64% (95% CI, 55% to 73%) and 92% (CI, 90% to 95%) for CTA and 62% (CI, 54% to 71%) and 84% (CI, 81% to 87%) for MRA.Limitations: Eighteen percent of the patients were included nonconsecutively. Digital subtraction angiography may be an imperfect reference test.Conclusion: Computed tomographic angiography and MRA are not reproducible or sensitive enough to rule out renal artery stenosis in hypertensive patients. Therefore, DSA remains the diagnostic method of choice. *For a list of the other investigators and research coordinators who participated in RADISH, see the Appendix. [ABSTRACT FROM AUTHOR]

Recent standards of care mention chest radiography (CR) but not chest computed tomography (CT) in routine annual follow-up of children with cystic fibrosis (CF). To minimise radiation risk, CT or CR should only be performed if they impact clinical decision making. We investigated whether in addition to a wide range of commonly used clinical parameters, chest CT and/or CR in routine follow-up of CF patients influence clinical decisions. 36 web based clinical vignettes (i.e. case simulations) were designed using clinical data from patients aged 8–18 years, randomly selected from two CF centres in The Netherlands. In a randomized cross-over design, clinicians assessed eight vignettes and suggested therapeutic/diagnostic management on two occasions, with a ten-week interval. Radiological information (CT or CR) was included at only one of the two assessments, in random order. Any differences in management could be attributed to information from CT or CR, and were compared by McNemar analysis. 44 European and Australian clinicians completed a total of 143 CT vignette pairs and 167 CR vignette pairs. CT was associated with a significant increase in antifungal treatment (Risk Ratio (RR) 2.8 (1.3–6.0, p =.02)), bronchoscopies (RR 1.6 (1.1–2.5, p =.04)), mycobacterial cultures (RR 1.3 (1.0–1.5, p =.02)), and 'need for hospitalization' (i.e. intravenous antibiotics and/or bronchoscopy) (RR 1.4 (1.0–1.9, p =.03)). CR led to a significant increase in inhaled antibiotics only (RR 1.3 (1.0–1.6, p =.04)). CT but not CR, at routine biennial follow-up was associated with several changes in treatment and/or diagnostic testing, including the need for hospitalization. • Chest CT scan influences clinical management in children with cystic fibrosis. • Chest X rays do not lead to relevant changes in clinical management. • This study offers support for the use of biennial CT in monitoring of cystic fibrosis. [ABSTRACT FROM AUTHOR]

Abstract: Background: To determine the comparative effectiveness and costs of a CT-strategy and a stress-electrocardiography-based strategy (standard-of-care; SOC-strategy) for diagnosing coronary artery disease (CAD). Methods: A decision analysis was performed based on a well-documented prospective cohort of 471 outpatients with stable chest pain with follow-up combined with best-available evidence from the literature. Outcomes were correct classification of patients as CAD− (no obstructive CAD), CAD+ (obstructive CAD without revascularization) and indication for Revascularization (using a combination reference standard), diagnostic costs, lifetime health care costs, and quality-adjusted life years (QALY). Parameter uncertainty was analyzed using probabilistic sensitivity analysis. Results: For men (and women), diagnostic cost savings were €245 (€252) for the CT-strategy as compared to the SOC-strategy. The CT-strategy classified 82% (88%) of simulated men (women) in the appropriate disease category, whereas 83% (85%) were correctly classified by the SOC-strategy. The long-term cost-effectiveness analysis showed that the SOC-strategy was dominated by the CT-strategy, which was less expensive (−€229 in men, −€444 in women) and more effective (+0.002 QALY in men, +0.005 in women). The CT-strategy was cost-saving (−€231) but also less effective compared to SOC (−0.003 QALY) in men with a pre-test probability of ≥70%. The CT-strategy was cost-effective in 100% of simulations, except for men with a pre-test probability ≥70% in which case it was 59%. Conclusions: The results suggest that a CT-based strategy is less expensive and equally effective compared to SOC in all women and in men with a pre-test probability <70%. [Copyright &y& Elsevier]