Analysis of breast cancer screening disparities in an academic health system

Thesis (Master's)--University of Washington, 2022Background: Breast cancer screening disparities among Black women have been recognized for decades yet persist. Health systems interested in implementing tailored interventions to improve breast cancer screening disparities must first understand local determinants. Econometrics methods can be employed to evaluate the contribution of factors to the mean difference in outcomes between two groups. Methods: We conducted a cross-sectional analysis including 20,147 individuals who identified as white (n=18,749) or Black (n=1,398) race and were eligible for breast cancer screening within a large academic health system. We evaluated predisposing characteristics (age, previous screening, use of patient portal, number of office visits, smoking status, medical conditions) and enabling resources at insurance and provider (primary care provider (PCP) specialty and training, PCP clinical full time equivalent, clinic location) levels. We conducted logistic regression analyses and a Blinder-Oaxaca (BO) decomposition to evaluate determinants in breast cancer screening disparities. Results: Black and white individuals differed on several factors; those who were Black were younger (mean age 61.5 ± 6.0 years vs. 63.2 ± 6.5 years, standardized mean difference (SMD)= -0.26), had less patient portal use (63.8% vs. 90.4%, SMD=0.67), higher rates of diabetes (29.8% vs. 11.8%, SMD= 0.45), higher rates of tobacco use (13.8% vs. 6.7%, SMD= 0.24), more Medicaid (19.0% vs. 6.2%, SMD= 0.39) insurance, and more often received primary care from a county hospital-based clinic (31.4% vs. 2.3%, SMD=0.82). Breast cancer screening was completed in 64.2% of Black individuals and 71.6% of white individuals (average marginal effect (AME) -0.07, 95% CI -0.10 to -0.05, p < 0.001). In the adjusted logistic regression analysis, Black individuals had a higher estimated likelihood to receive breast cancer screening as compared to white individuals (AME=0.06, 95% CI 0.03-0.09, p < 0.001). In the overall two-fold BO decomposition analysis, observed factors explained 12.7% difference in breast cancer screening. Contributing factors included patient portal use (4.1 percentage points or 32% of total difference), primary care site at a county hospital-based clinic (2.2 percentage points or 17.6% of total difference), diabetes (1.2 percentage points or 9.7% of total difference), and tobacco use (0.9 percentage points or 7.3% of total difference). Conclusion: In a BO decomposition analysis using data from a large academic health system, patient portal use, receiving care from a county-hospital based clinic, diabetes, and tobacco use were the factors that contributed most to the explained difference. These results can help to inform health system efforts to tailor interventions to improve racial disparities in breast cancer screening

Cytoarchitectural alterations are widespread in cerebral cortex in tuberous sclerosis complex

Tubers are cerebral cortical developmental malformations associated with epilepsy and autism in tuberous sclerosis complex (TSC). The disparity between tuber number and severity of neurological impairment often observed in TSC led us to hypothesize that microscopic structural abnormalities distinct from tubers may occur in TSC. Serial frontal to occipital lobe sections were prepared from five postmortem TSC brain specimens. Sections were probed with cresyl violet stain or NeuN antibodies to define cytoarchitectural abnormalities and phospho-S6 (Ser235/236) antibodies to define mammalian target of rapamycin complex 1 (mTORC1) pathway activation. Tubers identified in all specimens (mean, 5 tubers per brain specimen) were defined by abnormal cortical lamination, dysmorphic neurons, and giant cells (GCs) and exhibited robust phospho-S6 immunolabeling. Histopathological analysis of non-tuber cortices demonstrated that 32% of the sections exhibited microscopic cytoarchitectural alterations, whereas 68% of the sections did not. Four types of morphological abnormalities were defined including: (1) focal dyslamination, (2) heterotopic neurons, (3) small collections of giant cells (GCs) and neurons we termed "microtubers", (4) isolated GCs we termed "sentinel" cells. When compared with control cortex, phospho-S6 labeling was enhanced in microtubers and sentinel cells and in some but not all areas of dyslamination. There are microscopic cytoarchitectural abnormalities identified in postmortem TSC brain specimens that are distinct from tubers. mTORC1 cascade activation in these areas supports a widespread effect of TSC1 or TSC2 mutations on brain development. Tubers may represent the most dramatic developmental abnormality in TSC; however, more regionally pervasive yet subtle abnormalities may contribute to neurological disability in TS

Method for developing national quality indicators based on manual data extraction from medical records

International audienceDeveloping quality indicators (QI) for national purposes (eg, public disclosure, paying-for-performance) highlights the need to find accessible and reliable data sources for collecting standardised data. The most accurate and reliable data source for collecting clinical and organisational information still remains the medical record. Data collection from electronic medical records (EMR) would be far less burdensome than from paper medical records (PMR). However, the development of EMRs is costly and has suffered from low rates of adoption and barriers of usability even in developed countries. Currently, methods for producing national QIs based on the medical record rely on manual extraction from PMRs. We propose and illustrate such a method. These QIs display feasibility, reliability and discriminative power, and can be used to compare hospitals. They have been implemented nationwide in France since 2006. The method used to develop these QIs could be adapted for use in large-scale programmes of hospital regulation in other, including developing, countries

Cognitive Trajectory Phenotypes in Human Immunodeficiency Virus-Infected Patients.

ObjectiveThe presentation of cognitive impairments in HIV-infected individuals has transformed since the introduction of antiretroviral therapies. Although the overall prevalence of cognitive impairments has not changed considerably, frank dementia is now infrequent, and milder forms of cognitive impairments predominate. Mechanistic insights to the underlying causes of these residual cognitive impairments have been elusive, in part due to the heterogenous etiology of cognitive dysfunction in this population. Here, we sought to categorize longitudinal change in HIV-infected patients based on the performance in specific cognitive domains.DesignThis study consisted of 193 participants from the CHARTER cohort with detailed demographic, clinical, and neuropsychological testing data obtained from 2 study visits interspersed by ∼6 months. Cognitive testing assessed executive function, learning and delayed recall, working memory, verbal fluency, speed of information processing, and motor skills. Change scores were calculated for each domain between the 2 study visits. Dimension reduction and clustering was accomplished by principal component analysis of change scores and k-means clustering to identify cognitive domains that group together and groups of subjects with similar patterns of change.ResultsWe identified 4 distinct cognitive change phenotypes that included declines in: (1) verbal fluency, (2) executive function (3) learning and recall, and (4) motor function, with approximately equal numbers of participants in each phenotype.ConclusionsEach of the 4 cognitive change phenotypes identify deficits that imply perturbations in specific neural networks. Future studies will need to validate if cognitive change phenotypes are associated with alterations in associated neural pathways

Impaired insulin sensitivity is associated with worsening cognition in HIV-infected patients.

ObjectiveTo determine the association of insulin sensitivity and metabolic status with declining cognition in HIV-infected individuals.MethodsWe conducted targeted clinical and metabolic measures in longitudinal plasma samples obtained from HIV-infected patients enrolled in the Central Nervous System HIV Anti-Retroviral Therapy Effects Research Study (CHARTER). Findings were validated with plasma samples from the Multicenter AIDS Cohort Study (MACS). Patients were grouped according to longitudinally and serially assessed cognitive performance as having stably normal or declining cognition.ResultsPatients with declining cognition exhibited baseline hyperinsulinemia and elevated plasma c-peptide levels with normal c-peptide/insulin ratios, suggesting that insulin production was increased, but insulin clearance was normal. The association of hyperinsulinemia with worsening cognition was further supported by low high-density lipoprotein (HDL), high low-density lipoprotein/HDL ratio, and elevated cholesterol/HDL ratio compared to patients with stably normal cognition.ConclusionsThese findings suggest that hyperinsulinemia and impaired insulin sensitivity are associated with cognitive decline in antiretroviral therapy-treated HIV-infected patients