Philip W. Chu

Factors Associated with Mammography Utilization: A Systematic Quantitative Review of the Literature

OBJECTIVE A significant segment of women remains underscreened with mammography. We sought to summarize literature related to factors associated with receipt of mammography. For data sources, we used English language papers published between 1988 and 2007, including 221 studies describing 4,957,347 women. METHODS We calculated odds ratios (ORs) associated with receipt of mammography. Random effects modeling was used to assess trends in mammography utilization and to calculate summary multivariate point estimates. Results were stratified by age, race/ethnicity, and study year. We summarized results between 1988 and 2004 and compared recent years with these results. RESULTS Physician access barriers, such as not having a physician-recommend mammography (adjusted OR 0.16, 95% CI 0.08-0.33) and having no primary care provider (OR 0.41, 95% CI 0.32-0.53), were highly predictive of not obtaining mammography. Past screening behavior correlated strongly with receipt of mammography (clinical breast examination, adjusted OR 9.15, 95% CI 3.49-23.98) and Pap test (adjusted OR 3.45, 95% CI 2.12-5.62). With the exception of having no insurance (adjusted OR 0.47, 95% CI 0.39-0.57), several potential socioeconomic barriers did not appear to have an important impact on screening. Racial and ethnic differences were seen. Concerns about cost, mammography safety, and pain were more important to African American and Latina women, and having no insurance was more important to white and Chinese women. Cost concerns and the presence of a family history of breast cancer were less important to older women, whereas screening knowledge had a stronger impact on mammography use in women aged > or =65 years. When we compared study results before 2004 with those later, we found very little difference in the multivariate, adjusted ORs over time. CONCLUSIONS Women with poor access to physicians are much less likely to undergo mammography. Improving the frequency and scope of mammography recommendation by primary care providers is the single most important direct contribution the medical community can make toward increasing mammography use.

Positive Predictive Value of Specific Mammographic Findings according to Reader and Patient Variables

PURPOSE To evaluate the risk of cancer (positive predictive value [PPV]) associated with specific findings (mass, calcifications, architectural distortion, asymmetry) in mammographic examinations with abnormal results, to determine the distribution of these findings in examinations in which the patients received a diagnosis of cancer and examinations in which the patients did not, and to analyze PPV variation according to radiologist and patient factors. MATERIALS AND METHODS HIPAA-compliant institutional review board approval was obtained. PPV of mammographic findings was evaluated in a prospective cohort of 10,262 women who underwent 10,641 screening or diagnostic mammographic examinations with abnormal results between January 1998 and December 2002 in the San Francisco Mammography Registry. The cohort was linked with the Surveillance Epidemiology and End Results program to determine cancer status among these women. PPVs were calculated for each finding and were stratified according to patient characteristics, cancer type, and radiologist reader. RESULTS Cases of breast cancer (n = 1552) were identified (invasive, n = 1287; ductal carcinoma in situ, n = 270); in five, both kinds of breast cancer were recorded. Overall, of the number of interpretations, masses were most frequently noted in 56%, followed by calcifications in 29%, asymmetry in 12%, and architectural distortion in 4%. Masses, calcifications, architectural distortion, and developing asymmetry demonstrated similar PPVs in screening examinations (9.7%, 12.7%, 10.2%, and 7.4%, respectively), whereas one-view-only and focal asymmetry demonstrated lower PPVs (3.6% and 3.7%, respectively) and were a frequent reason for an abnormal result (42%). Overall, one (5%) in 20 invasive cancers was identified with asymmetry, one (6%) in 16 invasive cancers was identified with architectural distortion, one (21%) in five invasive cancers was identified with calcifications, and two (68%) in three invasive cancers were identified with a mass. CONCLUSION Five percent of invasive cancers were identified with asymmetry, and asymmetry is more weakly associated with cancer in screening examinations than are mass, calcifications, and architectural distortion.

Can Medicare billing claims data be used to assess mammography utilization among women ages 65 and older

Background:Medicare data may be a useful source for determining the utilization of mammography among elderly women, but the accuracy of these data has not been established. Objective:We determined whether Medicare physician billing claims are an accurate reflection of mammography utilization among women ages 65 and older and whether they can be used to assess the use of screening as compared with diagnostic mammography. Data Sources:Mammography use was assessed using Medicare billing claims and radiology reports from 2 mammography registries; the San Francisco Mammography Registry and the New Mexico Mammography Registry. Methods:Completeness of the Medicare data was assessed by comparing mammography use based on Medicare, with radiology reports from the mammography registries, which served as the referent standard. Capture rates for Medicare claims for individual mammograms were examined, and women were characterized as having undergone at least 1 mammogram within each 2-year period based on the Medicare data, and these rates were compared with the referent standard. To determine whether Medicare data can distinguish between screening and diagnostic mammography, we performed a classification analysis using the mammography registries screening/diagnostic designation as the referent standard (dependent variable) and Medicare claim information as the independent/predictor variable. On the basis of the mammogram level classification analysis, women were categorized as having been frequently screened (at least 2 screening mammograms spaced by 12 to 36 months), screened (at least 1 screening mammogram), or not screened. Subjects:Women ages 65 and older, diagnosed with breast cancer between 1992–1999, who had at least 1 mammogram between 1992–1999 were examined. Results:A total of 3340 mammograms were obtained in 1371 women between 1992 and 1999. Overall, 83% of mammograms obtained by these women had a corresponding billing claim in Medicare. This increased from 65% in 1992 to 90% in 1999. Of women who underwent at least 1 mammogram during each 2-year period per the referent standard, 94% of women were accurately classified by Medicare claims as also having undergone mammography during the same 2-year period. In multivariable analysis, a mammogram was more likely to be associated with a billing claim over time, for women 80 years or older, and for white and Asian as compared with Hispanic women. Neither socioeconomic status nor screening/diagnostic designation affected the likelihood that a mammogram would be associated with a billing claim. The Medicare data accurately categorized a given mammogram as screening or diagnostic for 87.5% of mammograms. Lastly, there was moderate to substantial agreement in the categorization of women as frequently screened, screened or not screened between the 2 data sets (weighted kappa 0.74, 95% confidence interval 0.70–0.78). Conclusion:Medicare administrative claims are reliable for assessment of mammography utilization and have become more accurate over time. Medicare claims data also provide a mechanism for designating mammography as screening or diagnostic, which subsequently may allow accurate description of a womans screening history.

Federally Qualified Health Centers and Private Practice Performance on Ambulatory Care Measures

BACKGROUND The 2010 Affordable Care Act relies on Federally Qualified Health Centers (FQHCs) and FQHC look-alikes (look-alikes) to provide care for newly insured patients, but ties increased funding to demonstrated quality and efficiency. PURPOSE To compare FQHC and look-alike physician performance with private practice primary care physicians (PCPs) on ambulatory care quality measures. METHODS The study was a cross-sectional analysis of visits in the 2006-2008 National Ambulatory Medical Care Survey. Performance of FQHCs and look-alikes on 18 quality measures was compared with private practice PCPs. Data analysis was completed in 2011. RESULTS Compared to private practice PCPs, FQHCs and look-alikes performed better on six measures (p<0.05); worse on diet counseling in at-risk adolescents (26% vs 36%, p=0.05); and no differently on 11 measures. Higher performance occurred in ACE inhibitors use for congestive heart failure (51% vs 37%, p=0.004); aspirin use in coronary artery disease (CAD; 57% vs 44%, p=0.004); β-blocker use for CAD (59% vs 47%, p=0.01); no use of benzodiazepines in depression (91% vs 84%, p=0.008); blood pressure screening (90% vs 86%, p<0.001); and screening electrocardiogram (EKG) avoidance in low-risk patients (99% vs 93%, p<0.001). Adjusting for patient characteristics yielded similar results, except that private practice PCPs no longer performed better on any measures. CONCLUSIONS FQHCs and look-alikes demonstrated equal or better performance than private practice PCPs on select quality measures despite serving patients who have more chronic disease and socioeconomic complexity. These findings can provide policymakers with some reassurance as to the quality of chronic disease and preventive care at Federally Qualified Health Centers and look-alikes, as they plan to use these health centers to serve 20 million newly insured individuals.

Liver steatosis: investigation of opposed-phase T1-weighted liver mr signal intensity loss and visceral fat measurement as biomarkers

PURPOSE To investigate if opposed-phase T1-weighted and fat-suppressed T2-weighted liver signal intensity (SI) loss and visceral fat measurement at magnetic resonance (MR) imaging and body mass index (BMI) are correlated with grade of liver steatosis in patients with nonalcoholic fatty liver disease (NAFLD) or hepatitis C virus (HCV) and human immunodeficiency virus (HIV)-related liver disease. MATERIALS AND METHODS Committee on Human Research approval and patient consent were obtained for this HIPAA-compliant study. Fifty-two patients (15 men, 37 women) with NAFLD (n = 29) or HCV and HIV-related liver disease (n = 23) underwent prospective contemporaneous MR imaging and liver biopsy. Liver SI loss was measured on opposed-phase T1-weighted and fat-suppressed T2-weighted MR images. Visceral fat area was measured at three levels on water-suppressed T1-weighted MR images (n = 44). Spearman rank correlation coefficients and recursive partitioning were used to examine correlations. RESULTS Histopathologic liver steatosis correlated well with liver SI loss on opposed-phase T1-weighted MR images (rho = 0.78), fat-suppressed T2-weighted MR images (rho = 0.75), and average visceral fat area (rho = 0.77) (all P < .01) but poorly with BMI (rho = 0.53, P < .01). Liver SI losses on opposed-phase T1-weighted MR imaging of less than 3%, at least 3% but less than 35%, at least 35% but less than 49%, and at least 49% corresponded to histopathologic steatosis grades of 0 (n = 16 of 17), 1 (n = 11 of 16), 2 (n = 7 of 13), and 3 (n = 5 of 6), respectively. A visceral fat area of greater than or equal to 73.8 cm(2) was associated with the presence of histopathologic steatosis in 41 of 44 patients. CONCLUSION Liver SI loss on opposed-phase T1-weighted MR images and visceral fat area may be used as biomarkers for the presence of liver steatosis and appear to be superior to BMI.

The Accuracy of Present-on-Admission Reporting in Administrative Data

OBJECTIVE To test the accuracy of reporting present-on-admission (POA) and to assess whether POA reporting accuracy differs by hospital characteristics. DATA SOURCES We performed an audit of POA reporting of secondary diagnoses in 1,059 medical records from 48 California hospitals. STUDY DESIGN We used patient discharge data (PDD) to select records with secondary diagnoses that are powerful predictors of mortality and could potentially represent comorbidities or complications among patients who either had a primary procedure of a percutaneous transluminal coronary angioplasty or a primary diagnosis of acute myocardial infarction, community-acquired pneumonia, or congestive heart failure. We modeled the relationship between secondary diagnoses POA reporting accuracy (over-reporting and under-reporting) and hospital characteristics. DATA COLLECTION We created a gold standard from blind reabstraction of the medical records and compared the accuracy of the PDD against the gold standard. PRINCIPAL FINDINGS The PDD and gold standard agreed on POA reporting in 74.3 percent of records, with 13.7 percent over-reporting and 11.9 percent under-reporting. For-profit hospitals tended to overcode secondary diagnoses as present on admission (odds ratios [OR] 1.96; 95 percent confidence interval [CI] 1.11, 3.44), whereas teaching hospitals tended to undercode secondary diagnoses as present on admission (OR 2.61; 95 percent CI 1.36, 5.03). CONCLUSIONS POA reporting of secondary diagnoses is moderately accurate but varies by hospitals. Steps should be taken to improve POA reporting accuracy before using POA in hospital assessments tied to payments.

In vivo evidence of glutamate toxicity in multiple sclerosis

There is increasing evidence that altered glutamate (Glu) homeostasis is involved in the pathophysiology of multiple sclerosis (MS). The aim of this study was to evaluate the in vivo effects of excess brain Glu on neuroaxonal integrity measured by N‐acetylaspartate (NAA), brain volume, and clinical outcomes in a large, prospectively followed cohort of MS subjects.

MRI Steatosis Grading: Development and Initial Validation of a Color Mapping System

OBJECTIVE The purpose of this article is to develop and validate a chemical-shift imaging-derived color mapping system for evaluation of liver steatosis. MATERIALS AND METHODS Opposed phase MRI was evaluated for 85 subjects (51 with presumed nonalcoholic fatty liver disease and 34 healthy volunteers). Liver signal intensity loss was compared with histologic analysis for 52 subjects, assuming grade 0 steatosis for healthy volunteers, to determine signal-intensity-loss threshold points differentiating steatosis grades and subsequent Spearman correlation. Color scale grading was then applied for 78 subjects. Interpretation of color maps for steatosis severity and heterogeneity was performed by three readers. Analyses of agreement among readers and of color map steatosis grade with biopsy were performed using weighted kappa values. RESULTS The numbers of subjects with steatosis grades 0, 1, 2, and 3 were 41, 12, 13, and 19, respectively. A correlation of 0.90 was obtained using selected threshold values of 5.9% or less, 6-26.1%, 26.2-36.8%, and greater than 36.8% for steatosis grades 0, 1, 2, and 3, respectively. Interobserver agreement for color map grading of steatosis was excellent (κ = 0.93-0.94). Color map interpretation for all readers also showed excellent agreement with histologic findings for whole liver (κ = 0.82-0.86) and estimated biopsy site location (κ = 0.81-0.86; anterior region of right lobe). Heterogeneous steatosis on color maps was identified in 56-60% of subjects with nonalcoholic fatty liver disease and in 7% of healthy volunteers and was associated with greater disagreement between color map and histology grading (61-74%) compared with the whole group (37-40%). CONCLUSION MRI-derived color map estimation of liver steatosis grade appears to be reproducible and accurate.

Choline metabolism, proliferation, and angiogenesis in nonenhancing grades 2 and 3 astrocytoma

To study choline metabolism in biopsies from nonenhancing Grade 2 (AS2) and Grade 3 (AS3) astrocytomas to determine whether (1) phosphocholine (PC) dominates in AS3, and (2) PC is associated with proliferation or angiogenesis. PC and glycerophosphocholine (GPC) are involved in phospholipid metabolism that accompanies mitosis. PC is the predominant peak in Grade 4 astrocytoma (GBM) while GPC dominates in AS2.

Prenatal screening for Down syndrome in England and Wales and population-based birth outcomes

OBJECTIVE Whether the introduction of antenatal screening for Down syndrome in England and Wales with serum biochemistry or ultrasound has led to improvements in patient outcomes is unknown. The purpose of this study was to relate pregnancy outcomes to the dominant method used for prenatal Down syndrome screening. STUDY DESIGN For the years 1989 through 1999, England and Wales were divided into geographically defined areas where specific hospitals, health authorities, and cytogenetic laboratories provided maternity care for well-defined populations. For each year from 1989 through 1999, the dominant Down syndrome screening method that was used in each area was determined. Outcomes for area-years that used serum biochemistry or ultrasound (first or second trimester) were compared with area-years that used advanced maternal age as the dominant screening method. The percent of Down syndrome cases that were diagnosed prenatally (effectiveness) and the number of invasive prenatal tests that were performed to diagnose each Down syndrome case prenatally (efficiency) were compared. RESULTS There were 5,980,519 births and 335,184 referrals for prenatal karyotyping (amniocentesis and chorionic villus sampling) that occurred in the area-years studied, of which 12,047 pregnancies were diagnosed as Down syndrome; 5393 cases of Down syndrome (45%) were diagnosed prenatally. Invasive testing increased from 4.4% of pregnancies in 1989 to 6.4% in 1997 and declined slightly in 1999 (5.8%). Prenatal diagnosis of Down syndrome cases rose from 28% in 1989 to 53% in 1999, and the number of invasive tests that were performed to diagnose each Down syndrome case fell from 89.7 to 47.7 (P [for trend]<.0001). Areas with serum or ultrasound as the dominant screening method detected 50% more Down syndrome cases in prenatally (52% and 53% vs 36%; P<.0001) and performed fewer invasive procedures to diagnose each Down syndrome case (60.7 and 52.0 vs 88.0; P<.0001) compared with areas in which advanced maternal age screening was dominant, despite serving populations with similar mean/median maternal ages. CONCLUSION In clinical practice, screening programs for Down syndrome that were based on maternal serum biochemistry or ultrasound were more effective and efficient than the screening programs that used advanced maternal age alone.