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1.
Breast Cancer Res Treat ; 197(1): 223-233, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36357711

ABSTRACT

PURPOSE: Over 50% of breast cancer patients prescribed a 5-year course of daily oral adjuvant endocrine therapy (ET) are nonadherent. We investigated the role of costs and cancer medication delivery mode and other medication delivery factors on adherence. METHODS: We conducted a retrospective cohort study of commercially insured and Medicare advantage patients with newly diagnosed breast cancer in 2007-2015 who initiated ET. We examined the association between 12-month ET adherence (proportion of days covered by fills ≥ 0.80) and ET copayments, 90-day prescription refill use, mail order pharmacy use, number of pharmacies, and synchronization of medications. We used regression models to estimate nonadherence risk ratios adjusted for demographics (age, income, race, urbanicity), comorbidities, total medications, primary cancer treatments, and generic AI availability. Sensitivity analyses were conducted using alternative specifications for independent variables. RESULTS: Mail order users had higher adherence in both commercial and Medicare-insured cohorts. Commercially insured patients who used mail order were more likely to be adherent if they had low copayments (< $5) and 90-day prescription refills. For commercially insured patients who used local pharmacies, use of one pharmacy and better synchronized refills were also associated with adherence. Among Medicare patients who used mail order pharmacies, only low copayments were associated with adherence, while among Medicare patients using local pharmacies both low copayments and 90-day prescriptions were associated with ET adherence. CONCLUSION: Out-of-pocket costs, medication delivery mode, and other pharmacy-related medication delivery factors are associated with adherence to breast cancer ET. Future work should investigate whether interventions aimed at streamlining medication delivery could improve adherence for breast cancer patients.


Subject(s)
Breast Neoplasms , Pharmaceutical Services , Humans , Aged , United States/epidemiology , Female , Breast Neoplasms/drug therapy , Retrospective Studies , Medicare , Medication Adherence , Adjuvants, Immunologic/therapeutic use
2.
Biometrics ; 79(4): 3023-3037, 2023 12.
Article in English | MEDLINE | ID: mdl-36932826

ABSTRACT

Many popular survival models rely on restrictive parametric, or semiparametric, assumptions that could provide erroneous predictions when the effects of covariates are complex. Modern advances in computational hardware have led to an increasing interest in flexible Bayesian nonparametric methods for time-to-event data such as Bayesian additive regression trees (BART). We propose a novel approach that we call nonparametric failure time (NFT) BART in order to increase the flexibility beyond accelerated failure time (AFT) and proportional hazard models. NFT BART has three key features: (1) a BART prior for the mean function of the event time logarithm; (2) a heteroskedastic BART prior to deduce a covariate-dependent variance function; and (3) a flexible nonparametric error distribution using Dirichlet process mixtures (DPM). Our proposed approach widens the scope of hazard shapes including nonproportional hazards, can be scaled up to large sample sizes, naturally provides estimates of uncertainty via the posterior and can be seamlessly employed for variable selection. We provide convenient, user-friendly, computer software that is freely available as a reference implementation. Simulations demonstrate that NFT BART maintains excellent performance for survival prediction especially when AFT assumptions are violated by heteroskedasticity. We illustrate the proposed approach on a study examining predictors for mortality risk in patients undergoing hematopoietic stem cell transplant (HSCT) for blood-borne cancer, where heteroskedasticity and nonproportional hazards are likely present.


Subject(s)
Machine Learning , Software , Humans , Bayes Theorem , Proportional Hazards Models , Uncertainty , Models, Statistical , Computer Simulation
3.
J Am Pharm Assoc (2003) ; 62(4): 1321-1328.e3, 2022.
Article in English | MEDLINE | ID: mdl-35393248

ABSTRACT

BACKGROUND: Adjuvant endocrine therapy (AET) for breast cancer reduces mortality, but one-third to one-half of patients discontinue it early or are nonadherent. OBJECTIVE: We developed a pilot single-site study of patients with evidence of early nonadherence to AET to assess the feasibility of a novel, clinical pharmacist-led intervention targeting symptom and medication management. METHODS: Patients with prescription fill records showing nonadherence were enrolled in a single-arm feasibility study. Automated reminders were sent by e-mail or text with a link to symptom monitoring assessments weekly for 1 month and monthly until 6 months. Clinical oncology pharmacists used guideline-based symptom management and other medication management tools to support adherence and ameliorate symptoms reported on the assessments. Patient-reported outcome assessments included physical, mental, and social health domains and self-efficacy to manage symptoms and medications. Feasibility outcomes included completion of symptom reports and pharmacist recommendations. RESULTS: Of 19 participants who were nonadherent who enrolled and completed initial assessments, 18 completed all final study procedures, with 14 completing all assessments and no patient missing more than 3 assessments. All 18 participants reported at least one of 3 symptom types, and the majority reported attempting pharmacist recommendations. Patient-reported measures of physical, mental, and social health and self-efficacy improved, and 44% of the patients became adherent. CONCLUSION: An intervention using pharmacists in an oncology practice to systematically monitor and manage symptoms shows promise to reduce symptoms, enhance support and self-efficacy, and improve adherence to AET.


Subject(s)
Breast Neoplasms , Pharmacists , Female , Humans , Breast Neoplasms/drug therapy , Feasibility Studies , Medication Adherence
4.
J Am Pharm Assoc (2003) ; 61(6): e25-e31, 2021.
Article in English | MEDLINE | ID: mdl-34340925

ABSTRACT

BACKGROUND: Yearly influenza vaccination is strongly recommended at age 65 and reimbursed by Medicare without copays or deductibles at pharmacies and clinical settings. Uptake is low among patients with a high risk for influenza complications and good access to specialist care, such as recent cancer survivors. We hypothesized that more accessible pharmacies could be associated with higher immunization uptake in such patients. OBJECTIVES: To determine whether pharmacy access is associated with influenza vaccination in subjects recently diagnosed with breast cancer, and whether this association differs by additional risk factors for influenza complications. METHODS: We examined a cohort of patients with stage 0-III breast cancer diagnosed 2011-2015 from the Surveillance, Epidemiology, and End Results-Medicare cancer registry. All retail pharmacies in the United States were identified, and pharmacy access was measured by assessing supply and demand in each census tract using a 2-stage floating catchment area approach that accounted for pharmacy driving distances recommended by the Centers for Medicare and Medicaid Services. We examined the association of pharmacy access with influenza vaccination after breast cancer diagnosis in regression models. RESULTS: More than 11% of 45,722 patients with breast cancer lived in census tracts where no pharmacies were within recommended driving distances from the population-weighted tract center. Vaccination in the year after diagnosis was less likely for patients in these very low-access tracts (adjusted odds ratio 0.92 [95% CI 0.86-0.96]), black (0.55 [0.51-0.60]) and Hispanic (0.76 [0.70-0.83]) women, and Medicaid recipients (0.74 [0.69-0.79]). Vaccination was inversely associated with per capita income in the subject's census tract, but there was no difference in the pharmacy effect by race, ethnicity, or census tract income. CONCLUSION: Very low pharmacy access is associated with modest reductions in vaccination that could be useful for policy and planning regarding vaccinator resources and outreach.


Subject(s)
Breast Neoplasms , Influenza Vaccines , Influenza, Human , Pharmacies , Pharmacy , Aged , Census Tract , Female , Humans , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Medicare , United States , Vaccination
5.
Breast Cancer Res Treat ; 179(1): 57-65, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31542875

ABSTRACT

PURPOSE: Advanced practice providers (APPs) have increasingly become members of the oncology care team. Little is known about the scope of care that APPs are performing nationally. We determined the prevalence and extent of APP practice and examined associations between APP care and scope of practice regulations, phase of cancer care, and patient characteristics. METHODS: We performed an observational study among women identified from Medicare claims as having had incident breast cancer in 2008 with claims through 2012. Outpatient APP care included at least one APP independently billing for cancer visits/services. APP scope of practice was classified as independent, reduced, or restricted. A logistic regression model with patient-level random effects was estimated to determine the probability of receiving APP care at any point during active treatment or surveillance. RESULTS: Among 42,550 women, 6583 (15%) received APP care, of whom 83% had APP care during the surveillance phase and 41% during the treatment phase. Among women who received APP care during a given year of surveillance, the overall proportion of APP-billed clinic visits increased with each additional year of surveillance (36% in Year 1 to 61% in Year 4). Logistic regression model results indicate that women were more likely to receive APP care if they were younger, black, healthier, had higher income status, or lived in a rural county or state with independent APP scope of practice. CONCLUSIONS: This study provides important clinical and policy-relevant findings regarding national practice patterns of APP oncology care. Among Medicare beneficiaries with incident breast cancer, 15% received outpatient oncology care that included APPs who were billing; most of this care was during the surveillance phase. Future studies are needed to define the degree of APP oncology practice and training that maximizes patient access and satisfaction while optimizing the efficiency and quality of cancer care.


Subject(s)
Advanced Practice Nursing/statistics & numerical data , Breast Neoplasms/epidemiology , Aged , Aged, 80 and over , Algorithms , Breast Neoplasms/ethnology , Female , Health Services Accessibility/statistics & numerical data , Humans , Logistic Models , Medical Oncology , Medicare , Prevalence , United States/epidemiology , United States/ethnology
6.
Pharmacoepidemiol Drug Saf ; 29(5): 550-557, 2020 05.
Article in English | MEDLINE | ID: mdl-32196839

ABSTRACT

PURPOSE: Clinical trials have clearly documented the survival benefit of aromatase inhibitors (AIs); however, many women fail to initiate (primary nonadherence) or remain adherent to AIs (secondary nonadherence). Prior studies have found that costs impact secondary nonadherence to medications but have failed to examine primary nonadherence. The purpose of this study is to examine primary and secondary adherence following the reduction in copays due to the introduction of generic AIs. METHODS: Using Surveillance, Epidemiology, and End Results-Medicare data, we identified 50 054 women diagnosed with incident breast cancer between 2008 and 2013. We compare women whose copays would change and those whose would not, due to the receipt of cost-sharing subsidies before and after generics were introduced using a difference-in-difference (DinD) analysis. To examine primary and secondary nonadherence, we rely on a multistate model with four states (Not yet initiated, User, Not Using, and Death). We adjusted for baseline factors using inverse probability treatment weights and then simulated adherence for 36 months following diagnosis. RESULTS: The generic introduction of AIs resulted in patients initiating AIs faster (DinD = -4.7%, 95%CI = -7.0, -2.3; patients not yet initiating treatment at 6-months), being more adherent (DinD ranging in absolute increase of 8.1%-10.4%) and being less likely to not be using the therapy (DinD range in absolute decrease of 1.2% at 6 months to 8.8% at 24 months) for women that do not receive a subsidy after generics were available. CONCLUSIONS: Introduction of generic alternatives to AIs significantly reduced primary and secondary nonadherence.


Subject(s)
Aromatase Inhibitors/therapeutic use , Breast Neoplasms/drug therapy , Drugs, Generic/therapeutic use , Medication Adherence , Aged , Aged, 80 and over , Aromatase Inhibitors/administration & dosage , Breast Neoplasms/mortality , Cohort Studies , Drugs, Generic/administration & dosage , Female , Humans , Medicare , Models, Theoretical , SEER Program , Survival Analysis , United States
7.
Cancer ; 125(21): 3818-3827, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31287559

ABSTRACT

BACKGROUND: Cancer contributes substantially to the life expectancy gap between US blacks and whites, and racial cancer disparities remain stubborn to eradicate. Disparities vary geographically, suggesting that they are not inevitable. METHODS: The authors examined the relationship between housing discrimination and the size of cancer disparities across large US metropolitan statistical areas (MSAs). MSA-level cancer disparities were measured using data from the US Centers for Disease Control and Prevention. Mortgage discrimination for each MSA was estimated using the Home Mortgage Disclosure Act database, and MSA racial segregation was determined using US Census data. Patterns of housing discrimination and cancer disparities were mapped, and the associations between these place-based factors and cancer disparities across MSAs were measured. RESULTS: Black-to-white cancer mortality disparities (rate ratios) varied geographically, ranging from 1.50 to 0.86; 88% of mortality ratios were >1, indicating higher mortality for blacks. In areas with greater mortgage discrimination, the gap between black and white cancer mortality rates was larger (correlation coefficient [r] = 0.32; P = .001). This relationship persisted in sex-specific analyses (males, r = 0.37; P < .001; females, r = 0.23; P = .02) and in models controlling for confounders. In contrast, segregation was inconsistently associated with disparities. Adjusting for incidence disparities attenuated, but did not eliminate, the correlation between mortgage discrimination and mortality disparities (r = 0.22-0.24), suggesting that cancer incidence and survival each account for part of the mortality disparity. CONCLUSIONS: Mortgage discrimination is associated with larger black-to-white cancer mortality disparities. Some areas are exceptions to this trend. Examination of these exceptions and of policies related to housing discrimination may offer novel strategies for explaining and eliminating cancer disparities.


Subject(s)
Health Status Disparities , Housing/statistics & numerical data , Neoplasms/therapy , Racism/statistics & numerical data , Urban Population/statistics & numerical data , Adult , Black or African American/statistics & numerical data , Female , Geography , Housing/economics , Humans , Male , Middle Aged , Neoplasms/diagnosis , Neoplasms/ethnology , Racism/prevention & control , Socioeconomic Factors , United States , White People/statistics & numerical data
8.
Cancer ; 125(22): 3960-3965, 2019 11 15.
Article in English | MEDLINE | ID: mdl-31373689

ABSTRACT

BACKGROUND: One-third to one-half of patients prescribed adjuvant endocrine therapy are nonadherent during the recommended 5-year endocrine therapy course. This study investigated whether poor pharmacy synchronization of medication fills (requiring refills on different days) acts as a barrier to adherence. METHODS: A cohort of older women with stage 0 to III endocrine receptor-positive breast cancer in 2011 was identified from the Surveillance, Epidemiology, and End Result-Medicare claims-linked cancer registry. Women with endocrine therapy and at least 1 other medication fill were identified, and the 3-month synchronization of their fills was calculated as 1 minus the quotient of the number of pharmacy visits and the number of filled medications. Regression models were used to examine the association between synchronization (in quartiles adjusted for the number of medications) and adherence to endocrine therapy (defined as a medication possession ratio ≥80%) over the subsequent year. RESULTS: During the 3 months after the first endocrine therapy prescription, the study cohort of 3212 women had a mean of 8.6 pharmacy visits (standard deviation, 4.7) with a mean synchronization of 0.3 (standard deviation, 0.2). Those in the third (odds ratio, 1.29; 95% confidence interval, 1.04-1.59) and fourth (most) medication number-adjusted synchronization quartiles (odds ratio, 1.49; 95% confidence interval, 1.19-1.86) were more likely to be adherent than those in the least. Multivariate model predictions showed that the proportion of patients who were adherent over 1 year varied from 68.9% in the least synchronized quartile to 76.6% in the most synchronized one. CONCLUSIONS: Prescription refill synchronization is strongly associated with adherence to endocrine therapy. Efforts to improve adherence should address this.


Subject(s)
Antineoplastic Agents, Hormonal , Breast Neoplasms/epidemiology , Medication Adherence , Pharmacies , Aged , Aged, 80 and over , Antineoplastic Agents, Hormonal/administration & dosage , Breast Neoplasms/diagnosis , Breast Neoplasms/drug therapy , Chemotherapy, Adjuvant , Female , Humans , Neoplasm Staging , Odds Ratio , SEER Program
9.
Cancer Causes Control ; 30(12): 1277-1282, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31531799

ABSTRACT

PURPOSE: To calculate tract-level estimates of liver cancer mortality in Wisconsin and identify relationships with racial and socioeconomic variables. METHODS: County-level standardized mortality ratios (SMRs) of liver cancer in Wisconsin were calculated using traditional indirect adjustment methods for cases from 2003 to 2012. Tract-level SMRs were calculated using adaptive spatial filtering (ASF). The tract-level SMRs were checked for correlations to a socioeconomic advantage index (SEA) and percent racial composition. Non-spatial and spatial regression analyses with tract-level SMR as the outcome were conducted. RESULTS: County-level SMR estimates were shown to mask much of the variance within counties across their tracts. Liver cancer mortality was strongly correlated with the percent of Black residents in a census tract and moderately associated with SEA. In the multivariate spatially-adjusted regression analysis, only Percent Black composition remained significantly associated with an increased liver cancer SMR. CONCLUSIONS: Using ASF, we developed a high-resolution map of liver cancer mortality in Wisconsin. This map provided details on the distribution of liver cancer that were inaccessible in the county-level map. These tract-level estimates were associated with several racial and socioeconomic variables.


Subject(s)
Black or African American/statistics & numerical data , Liver Neoplasms/epidemiology , Racial Groups/statistics & numerical data , Health Status Disparities , Humans , Regression Analysis , Wisconsin/epidemiology
10.
Physiol Genomics ; 50(6): 440-447, 2018 06 01.
Article in English | MEDLINE | ID: mdl-29602296

ABSTRACT

Studies exploring the development of hypertension have traditionally been unable to distinguish which of the observed changes are underlying causes from those that are a consequence of elevated blood pressure. In this study, a custom-designed servo-control system was utilized to precisely control renal perfusion pressure to the left kidney continuously during the development of hypertension in Dahl salt-sensitive rats. In this way, we maintained the left kidney at control blood pressure while the right kidney was exposed to hypertensive pressures. As each kidney was exposed to the same circulating factors, differences between them represent changes induced by pressure alone. RNA sequencing analysis identified 1,613 differently expressed genes affected by renal perfusion pressure. Three pathway analysis methods were applied, one a novel approach incorporating arterial pressure as an input variable allowing a more direct connection between the expression of genes and pressure. The statistical analysis proposed several novel pathways by which pressure affects renal physiology. We confirmed the effects of pressure on p-Jnk regulation, in which the hypertensive medullas show increased p-Jnk/Jnk ratios relative to the left (0.79 ± 0.11 vs. 0.53 ± 0.10, P < 0.01, n = 8). We also confirmed pathway predictions of mitochondrial function, in which the respiratory control ratio of hypertensive vs. control mitochondria are significantly reduced (7.9 ± 1.2 vs. 10.4 ± 1.8, P < 0.01, n = 6) and metabolomic profile, in which 14 metabolites differed significantly between hypertensive and control medullas ( P < 0.05, n = 5). These findings demonstrate that subtle differences in the transcriptome can be used to predict functional changes of the kidney as a consequence of pressure elevation.


Subject(s)
Gene Expression Profiling , Gene Expression Regulation , Inflammation/genetics , Kidney Medulla/physiology , Kidney Medulla/physiopathology , Metabolic Networks and Pathways/genetics , Perfusion , Animals , Bayes Theorem , Cell Respiration , Hypertension/genetics , Metabolome , Metabolomics , Mitochondria/metabolism , Rats, Inbred Dahl , Regression Analysis , Software
11.
Med Care ; 56(1): 78-84, 2018 01.
Article in English | MEDLINE | ID: mdl-29087982

ABSTRACT

BACKGROUND: Despite clear guidelines for its use and wide adoption, no population-based study has examined the extent to which patients with early stage breast cancer are benefiting from sentinel lymph node biopsy (SLNB) by being spared a potentially avoidable axillary lymph node dissection (ALND) and its associated morbidity. OBJECTIVE: Examine variation in type of axillary surgery performed by surgeon volume; investigate the extent and consequences of potentially avoidable ALND. RESEARCH DESIGN/SUBJECTS: Observational study of older women with pathologically node-negative stage I-II invasive breast cancer who underwent surgery in a SEER state in 2008-2009. MEASURES: Surgeon annual volume of breast cancer cases and type of axillary surgery were determined by Medicare claims. An estimated probability of excess lymphedema due to ALND was calculated. RESULTS: Among 7686 pathologically node-negative women, 49% underwent ALND (either initially or after SLNB) and 25% were operated on by low-volume surgeons. Even after adjusting for demographic and tumor characteristics, women treated by higher volume surgeons were less likely to undergo ALND [medium volume: odds ratio, 0.69 (95% confidence interval, 0.51-0.82); high volume: odds ratio, 0.59 (95% confidence interval, 0.45-0.76)]. Potentially avoidable ALND cases were estimated to represent 21% of all expected lymphedema cases. CONCLUSIONS: In this pathologically node-negative population-based breast cancer cohort, only half underwent solely SLNB. Patients treated by low-volume surgeons were more likely to undergo ALND. Resources and guidelines on the appropriate training and competency of surgeons to assure the optimal performance of SLNB should be considered to decrease rates of potentially avoidable ALND and lymphedema.


Subject(s)
Breast Neoplasms/surgery , Hospitals, High-Volume/statistics & numerical data , Hospitals, Low-Volume/statistics & numerical data , Lymphedema/epidemiology , Sentinel Lymph Node Biopsy/adverse effects , Aged , Aged, 80 and over , Axilla , Breast Neoplasms/pathology , Clinical Competence , Female , Humans , Lymph Nodes/surgery , Lymphedema/etiology , Medicare/statistics & numerical data , Prevalence , SEER Program , United States/epidemiology
12.
Biom J ; 59(4): 746-766, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28319254

ABSTRACT

We develop a Bayesian approach to subgroup analysis using ANOVA models with multiple covariates, extending an earlier work. We assume a two-arm clinical trial with normally distributed response variable. We also assume that the covariates for subgroup finding are categorical and are a priori specified, and parsimonious easy-to-interpret subgroups are preferable. We represent the subgroups of interest by a collection of models and use a model selection approach to finding subgroups with heterogeneous effects. We develop suitable priors for the model space and use an objective Bayesian approach that yields multiplicity adjusted posterior probabilities for the models. We use a structured algorithm based on the posterior probabilities of the models to determine which subgroup effects to report. Frequentist operating characteristics of the approach are evaluated using simulation. While our approach is applicable in more general cases, we mainly focus on the 2 × 2 case of two covariates each at two levels for ease of presentation. The approach is illustrated using a real data example.


Subject(s)
Analysis of Variance , Biometry/methods , Models, Statistical , Algorithms , Bayes Theorem , Humans , Probability
13.
J Natl Compr Canc Netw ; 14(7): 875-80, 2016 07.
Article in English | MEDLINE | ID: mdl-27407128

ABSTRACT

OBJECTIVES: Aromatase inhibitors (AIs) are standard adjuvant therapy for postmenopausal women with early-stage, estrogen receptor-positive breast cancer. We designed our study to determine whether women initiating adjuvant therapy with an AI underwent baseline bone mineral density testing, as well as what factors predicted adherence with testing guidelines. METHODS: Medicare Parts A, B, and D claims were used to identify a cohort of women aged 67 years and older with incident breast cancer in 2006 and 2007 who started AI therapy. Medicare claims provided information about bone density testing, as well as demographic and other treatment data through 2012. We also ascertained which patients were treated with bisphosphonates and studied the relationship of bisphosphonate therapy with bone density testing. RESULTS: Approximately two-thirds of patients had baseline bone density testing. Older age, comorbidity, low income, and black race were associated with lower rates of baseline bone density testing. Testing rates decreased substantially with increasing age from 73% for women aged 67 to 70 years to 51% for those 85 years of age and older (adjusted odds ratio for not being tested, 2.48 [Cl, 2.17-2.82]). The proportion of women who had neither bone density testing nor bisphosphonate therapy increased with age as well. CONCLUSIONS: Despite the importance of age as a risk factor for fractures, older women starting treatment with AIs for treatment of breast cancer are less likely to undergo recommended bone density assessment.


Subject(s)
Aromatase Inhibitors/therapeutic use , Breast Neoplasms/drug therapy , Aged , Aged, 80 and over , Bone Density Conservation Agents/therapeutic use , Breast Neoplasms/pathology , Cohort Studies , Female , Humans
14.
Stat Med ; 35(16): 2741-53, 2016 07 20.
Article in English | MEDLINE | ID: mdl-26854022

ABSTRACT

Bayesian additive regression trees (BART) provide a framework for flexible nonparametric modeling of relationships of covariates to outcomes. Recently, BART models have been shown to provide excellent predictive performance, for both continuous and binary outcomes, and exceeding that of its competitors. Software is also readily available for such outcomes. In this article, we introduce modeling that extends the usefulness of BART in medical applications by addressing needs arising in survival analysis. Simulation studies of one-sample and two-sample scenarios, in comparison with long-standing traditional methods, establish face validity of the new approach. We then demonstrate the model's ability to accommodate data from complex regression models with a simulation study of a nonproportional hazards scenario with crossing survival functions and survival function estimation in a scenario where hazards are multiplicatively modified by a highly nonlinear function of the covariates. Using data from a recently published study of patients undergoing hematopoietic stem cell transplantation, we illustrate the use and some advantages of the proposed method in medical investigations. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
Bayes Theorem , Survival Analysis , Humans , Proportional Hazards Models , Regression Analysis , Reproducibility of Results , Software
15.
WMJ ; 115(1): 17-21, 2016 Feb.
Article in English | MEDLINE | ID: mdl-27057575

ABSTRACT

BACKGROUND: Cancer health disparities by race, ethnicity, socioeconomic status, and geography are a top public health priority. Breast and colorectal cancer, in particular, have been shown to exhibit significant disparities and contribute a large proportion of morbidity and mortality from cancer. In addition, breast and colorectal cancer offer targets for prevention and control, including nutrition, physical activity, screening, and effective treatments to prolong and enhance the quality of survival. However, despite the investment of significant time and resources over many years, breast and colorectal cancer disparities persist, and in some cases, may be growing. METHODS: This paper examines breast and colorectal cancer survival disparities in an 8-county region in southeastern Wisconsin, including the City of Milwaukee. Cox proportional hazards models were used to examine survival trends, and a new adaptation of adaptive spatial filtering--a disease mapping method--was used to examine spatial patterns of survival. RESULTS: Disparities by race and ethnicity are revealed, and spatial analyses identify specific areas within the study region that have lower than expected survival rates. CONCLUSIONS: Cancer control efforts in southeastern Wisconsin should focus on black/African American and Hispanic/Latina women to reduce breast cancer survival disparities, and black/African American populations to reduce colorectal cancer disparities. Evidence indicates that targeted interventions may be needed to serve populations in the Milwaukee and Kenosha metropolitan areas, as well as areas of Walworth, Ozaukee, and Waukesha counties.


Subject(s)
Breast Neoplasms/mortality , Colorectal Neoplasms/mortality , Survival Analysis , Breast Neoplasms/ethnology , Colorectal Neoplasms/ethnology , Female , Humans , Incidence , Male , Registries , Wisconsin/epidemiology
16.
Physiol Genomics ; 46(11): 398-410, 2014 Jun 01.
Article in English | MEDLINE | ID: mdl-24714719

ABSTRACT

The goal of the present study was to narrow a region of chromosome 13 to only several genes and then apply unbiased statistical approaches to identify molecular networks and biological pathways relevant to blood-pressure salt sensitivity in Dahl salt-sensitive (SS) rats. The analysis of 13 overlapping subcongenic strains identified a 1.37 Mbp region on chromosome 13 that influenced the mean arterial blood pressure by at least 25 mmHg in SS rats fed a high-salt diet. DNA sequencing and analysis filled genomic gaps and provided identification of five genes in this region, Rfwd2, Fam5b, Astn1, Pappa2, and Tnr. A cross-platform normalization of transcriptome data sets obtained from our previously published Affymetrix GeneChip dataset and newly acquired RNA-seq data from renal outer medullary tissue provided 90 observations for each gene. Two Bayesian methods were used to analyze the data: 1) a linear model analysis to assess 243 biological pathways for their likelihood to discriminate blood pressure levels across experimental groups and 2) a Bayesian graphical modeling of pathways to discover genes with potential relationships to the candidate genes in this region. As none of these five genes are known to be involved in hypertension, this unbiased approach has provided useful clues to be experimentally explored. Of these five genes, Rfwd2, the gene most strongly expressed in the renal outer medulla, was notably associated with pathways that can affect blood pressure via renal transcellular Na(+) and K(+) electrochemical gradients and tubular Na(+) transport, mitochondrial TCA cycle and cell energetics, and circadian rhythms.


Subject(s)
Genome/genetics , Hypertension/genetics , Hypertension/metabolism , Signal Transduction/genetics , Animals , Arterial Pressure/genetics , Bayes Theorem , Circadian Rhythm/genetics , Citric Acid Cycle/genetics , Gene Expression Profiling/methods , Male , Mitochondria/genetics , Potassium/metabolism , Rats , Rats, Inbred Dahl , Sequence Analysis, DNA/methods , Sodium/metabolism , Sodium Chloride, Dietary/metabolism
17.
medRxiv ; 2024 May 09.
Article in English | MEDLINE | ID: mdl-38766030

ABSTRACT

Allogeneic hematopoietic cell transplantation (HCT) is one of the only curative treatment options for patients suffering from life-threatening hematologic malignancies; yet, the possible adverse complications can be serious even fatal. Matching between donor and recipient for 4 of the HLA genes is widely accepted and supported by the literature. However, among 8/8 allele matched unrelated donors, there is less agreement among centers and transplant physicians about how to prioritize donor characteristics like additional HLA loci (DPB1 and DQB1), donor sex/parity, CMV status, and age to optimize transplant outcomes. This leads to varying donor selection practice from patient to patient or via center protocols. Furthermore, different donor characteristics may impact different post transplant outcomes beyond mortality, including disease relapse, graft failure/rejection, and chronic graft-versus-host disease (components of event-free survival, EFS). We develop a general methodology to identify optimal treatment decisions by considering the trade-offs on multiple outcomes modeled using Bayesian nonparametric machine learning. We apply the proposed approach to the problem of donor selection to optimize overall survival and event-free survival, using a large outcomes registry of HCT recipients and their actual and potential donors from the Center for International Blood and Marrow Transplant Research (CIBMTR). Our approach leads to a donor selection strategy that favors the youngest male donor, except when there is a female donor that is substantially younger.

18.
Cancer Med ; 13(14): e7397, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39030995

ABSTRACT

BACKGROUND: Interventions aimed at upstream factors contributing to late-stage diagnoses could reduce disparities and improve breast cancer outcomes. This study examines the association between measures of housing stability and contemporary mortgage lending bias on breast cancer stage at diagnosis among older women in the United States. METHODS: We studied 67,588 women aged 66-90 from the SEER-Medicare linked database (2010-2015). The primary outcome was breast cancer stage at diagnosis. Multinomial regression models adjusted for individual and neighborhood socio-economic factors were performed using a three-category outcome (stage 0, early stage, and late stage). Key census tract-level independent variables were residence in the same house as the previous year, owner-occupied homes, and an index of contemporary mortgage lending bias. RESULTS: In models adjusted for individual factors, higher levels of mortgage lending bias were associated with later stage diagnosis (RR = 1.10, 95% CI 1.02-1.20; RR = 1.31, 95% CI 1.16-1.49; RR = 1.41, 95% CI 1.24-1.60 for least to high, respectively). In models adjusted for individual and neighborhood socio-economic factors, moderate and high levels of mortgage lending bias were associated with later stage diagnosis (RR = 1.16, 95% CI 1.02-1.33 for moderate and RR = 1.18, 95% CI 1.02-1.37 for high). Owner occupancy and tenure were not associated with later stage diagnosis in adjusted models. CONCLUSIONS: Contemporary mortgage lending bias demonstrated a significant gradient relationship with later stage at diagnosis of breast cancer. Policy interventions aimed at reducing place-based mortgage disinvestment and its impacts on local resources and opportunities should be considered as part of an overall strategy to decrease late-stage breast cancer diagnosis and improve prognosis.


Subject(s)
Breast Neoplasms , Housing , Neoplasm Staging , SEER Program , Humans , Breast Neoplasms/diagnosis , Breast Neoplasms/pathology , Breast Neoplasms/epidemiology , Female , United States , Aged , Aged, 80 and over , Socioeconomic Factors , Neighborhood Characteristics , Medicare
19.
Am J Med Qual ; 38(5): 229-237, 2023.
Article in English | MEDLINE | ID: mdl-37678301

ABSTRACT

Despite the widespread adoption of early warning systems (EWSs), it is uncertain if their implementation improves patient outcomes. The authors report a pre-post quasi-experimental evaluation of a commercially available EWS on patient outcomes at a 700-bed academic medical center. The EWS risk scores were visible in the electronic medical record by bedside clinicians. The EWS risk scores were also monitored remotely 24/7 by critical care trained nurses who actively contacted bedside nurses when a patient's risk levels increased. The primary outcome was inpatient mortality. Secondary outcomes were rapid response team calls and activation of cardiopulmonary arrest (code-4) response teams. The study team conducted a regression discontinuity analysis adjusting for age, gender, insurance, severity of illness, risk of mortality, and hospital occupancy at admission. The analysis included 53,229 hospitalizations. Adjusted analysis showed no significant change in inpatient mortality, rapid response team call, or code-4 activations after implementing the EWS. This study confirms the continued uncertainty in the effectiveness of EWSs and the need for further rigorous examinations of EWSs.


Subject(s)
Heart Arrest , Hospital Rapid Response Team , Humans , Hospitalization , Critical Care , Heart Arrest/therapy , Vital Signs
20.
Health Place ; 83: 103090, 2023 09.
Article in English | MEDLINE | ID: mdl-37531804

ABSTRACT

BACKGROUND: Residential segregation is an important factor that negatively impacts cancer disparities, yet studies yield mixed results and complicate clear recommendations for policy change and public health intervention. In this study, we examined the relationship between local and Metropolitan Statistical Area (MSA) measures of Black isolation (segregation) and survival among older non-Hispanic (NH) Black women with breast cancer (BC) in the United States. We hypothesized that the influence of local isolation on mortality varies based on MSA isolation-specifically, that high local isolation may be protective in the context of highly segregated MSAs, as ethnic density may offer opportunities for social support and buffer racialized groups from the harmful influences of racism. METHODS: Local and MSA measures of isolation were linked by Census Tract (CT) with a SEER-Medicare cohort of 5,231 NH Black women aged 66-90 years with an initial diagnosis of stage I-IV BC in 2007-2013 with follow-up through 2018. Proportional and cause-specific hazards models and estimated marginal means were used to examine the relationship between local and MSA isolation and all-cause and BC-specific mortality, accounting for covariates (age, comorbidities, tumor stage, and hormone receptor status). FINDINGS: Of 2,599 NH Black women who died, 40.0% died from BC. Women experienced increased risk for all-cause mortality when living in either high local (HR = 1.20; CI = 1.08-1.33; p < 0.001) or high MSA isolation (HR = 1.40; CI = 1.17-1.67; p < 0.001). A similar trend existed for BC-specific mortality. Pairwise comparisons for all-cause mortality models showed that high local isolation was hazardous in less isolated MSAs but was not significant in more isolated MSAs. INTERPRETATION: Both local and MSA isolation are independently associated with poorer overall and BC-specific survival for older NH Black women. However, the impact of local isolation on survival appears to depend on the metropolitan area's level of segregation. Specifically, in highly segregated MSAs, living in an area with high local isolation is not significantly associated with poorer survival. While the reasons for this are not ascertained in this study, it is possible that the protective qualities of ethnic density (e.g., social support and buffering from experiences of racism) may have a greater role in more segregated MSAs, serving as a counterpart to the hazardous qualities of local isolation. More research is needed to fully understand these complex relationships. FUNDING: National Cancer Institute.


Subject(s)
Breast Neoplasms , Aged , Female , Humans , Ethnicity , Health Status Disparities , Medicare , United States , Black or African American
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