Bio

Bio


Cardiology Fellow and Health Services Researcher at Stanford University School of Medicine. Graduate of Stanford Internal Medicine / Global Health residency program, former Chief Resident.

Professional interests include epidemiology, qualitative research, and health services research focused on heart disease in the developing world and domestic vulnerable populations. Long-term interests include developing and researching appropriate technologies and innovations for use in low-resource settings, with an emphasis on design thinking and social justice. Areas of application include non-communicable diseases and cardiovascular conditions. Other formal training includes bench and translational research background in immunology, cancer biology, and neuroscience. Funded by Spectrum TL1 NIH training grant, completed MS in Epidemiology and Clinical Research in 2018.

Clinical Focus


  • Cardiology
  • Global Health
  • Fellow

Academic Appointments


  • Clinical Instructor, Medicine

Administrative Appointments


  • Fellow, Stanford Department of Medicine, Division of Cardiovascular Medicine (2018 - Present)
  • Clinical Instructor / Attending Physician, Stanford Department of Medicine, VA Palo Alto Medical Center (2016 - 2018)
  • Chief Resident, Stanford Internal Medicine Residency Program (2016 - 2017)

Honors & Awards


  • Alpha Omega Alpha Medical Honor Society, AOA, Stanford University Chapter (2017)
  • Gold Humanism Honor Society, Arnold P. Gold Foundation (2012)
  • TL1 Gold Ribbon Presentation, Association for Clinical and Translational Science (2018)
  • Stanford Cardiovascular Institute Travel Award, Stanford Cardiovascular Institute (2018)
  • Johnson and Johnson Global Health Scholar, Yale/Stanford Johnson & Johnson Global Health Scholars Program (2015)
  • Johnson and Johnson Global Health Scholar, Yale/Stanford Johnson & Johnson Global Health Scholars Program (2014)
  • Asian Pacific American Medical Student Association Global Health Fellowship, Asian Pacific American Medical Student Association (2012)
  • Stanford Medical Scholars Research Fellowship, Stanford University School of Medicine (2009-2011)
  • The John E. Linck III Memorial Graduation Prize, Yale University (2008)
  • Yale College Dean’s Research Fellowship in the Sciences, Yale University (2007)
  • Yale Science and Engineering Research Presentation Travel Prize, Yale University (2007)
  • 1st Place Presentation, Yale Undergraduate Research Symposium in the Biological Sciences, Yale University (2007)
  • The Paul K. and Evalyn Elizabeth Cook Richter Summer Fellowship, Yale University (2007)
  • The Gary Stein Memorial Internship, Yale University (2006)
  • Robert C. Byrd Congressional Honors Scholarship, United States Department of Education (2005)

Boards, Advisory Committees, Professional Organizations


  • Faculty Fellow, Stanford Center for Innovation in Global Health (2016 - Present)
  • Representative, Chief Resident's Council, Department of Graduate Medical Education, Stanford University Medical Center (2016 - 2017)
  • Representative,Committee on Residency Reform, Department of Medicine, Stanford University Medical Center (2014 - 2016)
  • Resident Member, American College of Cardiology (2015 - 2017)
  • Resident: Medicine/Global Health, Stanford University Hospital (2013 - 2016)
  • Resident Member, American College of Physicians (2013 - 2016)
  • Member, Stanford Center for Population Health Sciences (2015 - Present)
  • Member, Stanford Society of Physician Scholars (2013 - Present)
  • Member, Young Professionals Chronic Disease Network (2013 - Present)
  • Member, California Medical Association (2013 - Present)
  • Editor-in-Chief, The Stanford Medical Student Clinical Journal (2010 - 2012)

Professional Education


  • Board Certification: Fellow, American Board of Internal Medicine (2016)
  • Master of Science, Stanford University School of Medicine, Epidemiology, Clinical Research (2018)
  • Residency:Stanford Medicine Internal Medicine Residency Training (2016) CA
  • Doctor of Medicine, Stanford University School of Medicine, Clinical Research, Immunology, Global Health (2013)
  • Bachelor of Science, Yale University, Molecular, Cellular & Developmental Biology (2008)
  • Non-degree Program, American Heart Association (AHA) Ten-Day Seminar on the Epidemiology and Prevention of Cardiovascular Disease, Epidemiology (2017)
  • Non-degree Program, Hasso Plattner Institute of Design at Stanford University, Entrepreneurial Design for Extreme Affordability Program (2012)

Community and International Work


  • Johnson & Johnson Global Health Scholar, Kampala, Uganda

    Partnering Organization(s)

    Mulago Hospital

    Location

    International

    Ongoing Project

    Yes

    Opportunities for Student Involvement

    No

  • Johnson & Johnson Global Health Scholar, Kigali, Rwanda

    Partnering Organization(s)

    University Central Hospital of Kigali, Rwanda

    Location

    International

    Ongoing Project

    No

    Opportunities for Student Involvement

    No

  • Clinical Director, Co-Founder, Dhaka, Bangladesh

    Partnering Organization(s)

    International Centre for Diarrhoeal Disease Research, Bangladesh

    Location

    International

    Ongoing Project

    No

    Opportunities for Student Involvement

    No

  • Medical Student Clinical Volunteer, Rosebud, SD

    Partnering Organization(s)

    ASB / Rosebud Lakota Indian Reservation / Habitat for Humanity

    Populations Served

    Rosebud Lakota Reservation

    Location

    US

    Ongoing Project

    No

    Opportunities for Student Involvement

    No

  • Administrative/Media Intern, Kathmandu, Nepal

    Partnering Organization(s)

    Nyaya Health / Possible Health

    Populations Served

    Sanfebagar, Nepal

    Ongoing Project

    No

    Opportunities for Student Involvement

    No

  • Physician Volunteer, Menlo Park, CA

    Partnering Organization(s)

    Cardinal Free Clinics

    Populations Served

    Uninsured Populations of San Mateo County

    Location

    Bay Area

    Ongoing Project

    Yes

    Opportunities for Student Involvement

    No

  • Hepatitis B Clinic Coordinator, San Jose, CA

    Partnering Organization(s)

    Pacific Free Clinic

    Populations Served

    Uninsured Patients in Santa Clara County

    Location

    Bay Area

    Ongoing Project

    No

    Opportunities for Student Involvement

    No

  • Social Services Volunteer, Fair Haven, CT

    Partnering Organization(s)

    HAVEN Free Clinic

    Populations Served

    Uninsured Patients in New Haven County, CT

    Location

    US

    Ongoing Project

    No

    Opportunities for Student Involvement

    No

  • Health Educator, New Haven, CT

    Topic

    Health Education

    Partnering Organization(s)

    Community Health Educators

    Location

    US

    Ongoing Project

    No

    Opportunities for Student Involvement

    No

Patents


  • Andrew Chang, Carey Lee, Pamela Pavkov, Karen Lee, Michael Strasser. "United States Patent Attorney docket number: S11-190 Provisional Patent: “Low Cost Bubble CPAP Device”", Jun 1, 2011

Research & Scholarship

Current Research and Scholarly Interests


My research interests center around the epidemiology and health services research of heart disease, with an emphasis on vulnerable populations both international and domestic. Ongoing global health projects include mixed methods research in women of reproductive age in Uganda with rheumatic heart disease, characterizing this population and their attitudes towards fertility, contraception, and anticoagulation. Epidemiological profiling of this patient population is ongoing. Domestic investigation consists of understanding the impact of health insurance payer plan on the treatment of atrial fibrillation, particularly with oral anticoagulants. Other research interests include cost-effectiveness analysis, health economics, and device/service innovation for low-resource settings.

Current Clinical Interests


  • Cardiovascular Disease
  • Rheumatic Heart Disease
  • Valvular Heart Disease
  • Atrial Fibrillation
  • Anticoagulation
  • Echocardiography

Publications

All Publications


  • Association of Healthcare Plan with Atrial Fibrillation Prescription Patterns. Clinical cardiology Chang, A. Y., Askari, M., Fan, J., Heidenreich, P. A., Ho, P. M., Mahaffey, K. W., Ullal, A. J., Perino, A. C., Turakhia, M. P. 2018

    Abstract

    Atrial fibrillation (AF) is treated by many types of physician specialists, including primary care physicians (PCPs). Health plans have different policies for how patients encounter these providers, and these may affect selection of AF treatment strategy.We hypothesized that healthcare plans with PCP-gatekeeping to specialist access may be associated with different pharmacologic treatments for AF.We performed a retrospective cohort study using a commercial pharmaceutical claims database. We utilized logistic regression models to compare odds of prescription of oral anticoagulant (OAC), non-vitamin K-dependent oral anticoagulant (NOAC), rate control, and rhythm control medications used to treat AF between patients with PCP-gated healthcare plans (e.g. HMO, EPO, POS) and patients with non-PCP-gated healthcare plans (e.g. PPO, CHDP, HDHP, Comprehensive) between 2007 and 2012. We also calculated median time to receipt of therapy within 90 days of index AF diagnosis.We found similar odds of OAC prescription at 90 days following new AF diagnosis in patients with PCP-gated plans compared to those with non-PCP-gated plans (OR: OAC 1.01, p=0.84; warfarin 1.05, p=0.08). Relative odds were similar for rate control (1.17, p<0.01) and rhythm control agents (0.93, p=0.03). However, PCP-gated plan patients had slightly lower likelihood of being prescribed NOACs (0.82, p=0.001) than non-gated plan patients. Elapsed time until receipt of medication was similar between PCP-gated and non-gated groups across drug classes.Pharmaceutical claims data do not suggest that PCP-gatekeeping by healthcare plans is a structural barrier to AF therapy, although it was associated with lower use of NOACs.

    View details for DOI 10.1002/clc.23042

    View details for PubMedID 30098034

  • Patient and facility variation in costs of catheter ablation for atrial fibrillation. Journal of cardiovascular electrophysiology Perino, A. C., Fan, J., Schmitt, S., Kaiser, D. W., Heidenreich, P. A., Narayan, S. M., Wang, P. J., Chang, A. Y., Turakhia, M. P. 2018

    Abstract

    Cost-effectiveness or value of cardiovascular therapies may be undermined by unwarranted cost variation, particularly for heterogeneous procedures such as catheter ablation for atrial fibrillation (AF). We sought to characterize cost variation of AF ablation in the U.S. health care system and the relationship between cost and outcomes.We performed a retrospective cohort study using data from the MarketScan® commercial claims and Medicare supplemental databases including patients who received an AF ablation from 2007 through 2011. We aggregated encounter cost, reflecting total payments received for the encounter, to the facility level to calculate median facility cost. We classified procedures as outpatient or inpatient and assessed for association between cost and 30-day and one-year outcomes. The analysis cohort included 9,415 AF ablations (59±11 years; 28% female; 52% outpatient) occurring at 327 facilities, with large cost variation across facilities (median: $25,100; 25th percentile: $18,900, 75th percentile: $35,600, 95th percentile: $57,800). Among outpatient procedures, there was reduced health care utilization in higher cost quintiles with reductions in rehospitalization at 30-days (Quintile 1: 16.1%, Quintile 5: 8.8%, p < 0.001) and one-year (Quintile 1: 34.8%, Quintile 5: 25.6%, p < 0.001), which remained significant in multivariate analysis.Although median costs of AF ablation are below amounts used in prior cost-effectiveness studies that demonstrated good value, large facility variation in cost suggests opportunities for cost reduction. However, for outpatient encounters, association of cost to modestly improved outcomes suggests cost containment strategies could have variable effects. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1111/jce.13655

    View details for PubMedID 29864193

  • Motivations of women in Uganda living with rheumatic heart disease: A mixed methods study of experiences in stigma, childbearing, anticoagulation, and contraception. PloS one Chang, A. Y., Nabbaale, J., Nalubwama, H., Okello, E., Ssinabulya, I., Longenecker, C. T., Webel, A. R. 2018; 13 (3): e0194030

    Abstract

    Rheumatic heart disease (RHD) is a leading cause of premature mortality in low- and middle-income countries (LMICs). Women of reproductive age are a unique and vulnerable group of RHD patients, due to increased risk of cardiovascular complications and death during pregnancy. Yet, less than 5% of women of childbearing age with RHD in LMICs use contraceptives, and one in five pregnant women with RHD take warfarin despite known teratogenicity. It is unclear whether this suboptimal contraception and anticoagulant use during pregnancy is due to lack of health system resources, limited health literacy, or social pressure to bear children.We conducted a mixed methods study of 75 women living with RHD in Uganda. Questionnaires were administered to 50 patients. Transcripts from three focus groups with 25 participants were analyzed using qualitative description methodology.Several themes emerged from the focus groups, including pregnancy as a calculated risk; misconceptions about side-effects of contraceptives and anticoagulation; reproductive decision-making control by male partners, in-laws, or physicians; abandonment of patients by male partners; and considerable stigma against heart disease patients for both their reproductive and financial limitations (often worse than that directed against HIV patients). All questionnaire respondents were told by physicians that their hearts were not strong enough to support a pregnancy. Only 14% used contraception while taking warfarin. All participants felt that society would look poorly on a woman who cannot have children due to a heart condition.To our knowledge, this is the first qualitative study of female RHD patients and their attitudes toward cardiovascular disorders and reproduction. Our results suggest that health programs targeting heart disease in LMICs must pay special attention to the needs of women of childbearing age. There are opportunities for improved family/societal education programs and community engagement, leading to better outcomes and patient empowerment.

    View details for DOI 10.1371/journal.pone.0194030

    View details for PubMedID 29590159

    View details for PubMedCentralID PMC5874006

  • IL6 Signaling in Peripheral Blood T Cells Predicts Clinical Outcome in Breast Cancer. Cancer research Wang, L., Miyahira, A. K., Simons, D. L., Lu, X., Chang, A. Y., Wang, C., Suni, M. A., Maino, V. C., Dirbas, F. M., Yim, J., Waisman, J., Lee, P. P. 2017; 77 (5): 1119-1126

    Abstract

    IL6 is a pleiotropic cytokine with both pro- and anti-inflammatory properties, which acts directly on cancer cells to promote their survival and proliferation. Elevated serum IL6 levels negatively correlate with survival of cancer patients, which is generally attributed to the direct effects of IL6 on cancer cells. How IL6 modulates the host immune response in cancer patients is unclear. Here, we show the IL6 signaling response in peripheral blood T cells is impaired in breast cancer patients and is associated with blunted Th17 differentiation. The mechanism identified involved downregulation of gp130 and IL6Rα in breast cancer patients and was independent of plasma IL6 levels. Importantly, defective IL6 signaling in peripheral blood T cells at diagnosis correlated with worse relapse-free survival. These results indicate that intact IL6 signaling in T cells is important for controlling cancer progression. Furthermore, they highlight a potential for IL6 signaling response in peripheral blood T cells at diagnosis as a predictive biomarker for clinical outcome of breast cancer patients. Cancer Res; 77(5); 1119-26. ©2016 AACR.

    View details for DOI 10.1158/0008-5472.CAN-16-1373

    View details for PubMedID 27879265

    View details for PubMedCentralID PMC5334262

  • Regenerative Medicine: Potential Mechanisms of Cardiac Recovery in Takotsubo Cardiomyopathy. Current treatment options in cardiovascular medicine Chang, A. Y., Kittle, J. T., Wu, S. M. 2016; 18 (3): 20-?

    Abstract

    Takotsubo cardiomyopathy is an increasingly reported cause of acute chest pain and acute heart failure and is often associated with significant hemodynamic compromise. The illness is remarkable for the reversibility in systolic dysfunction seen in the disease course. While the pathophysiology of takotsubo syndrome is not completely elucidated, research suggests the presence of a cytoprotective process that allows the myocardium to recover following the inciting insult. Here, we summarize molecular and histologic studies exploring the response to injury in takotsubo disease and provide some discussion on how they may contribute to further investigations in cardiac recovery and regeneration.

    View details for DOI 10.1007/s11936-016-0443-0

    View details for PubMedID 26874708

    View details for PubMedCentralID PMC4957545

  • The Global Health Implications of e-Cigarettes. JAMA Chang, A. Y., Barry, M. 2015; 314 (7): 663-664

    View details for DOI 10.1001/jama.2015.8676

    View details for PubMedID 26284714

  • Evaluating the Cost-effectiveness of Catheter Ablation of Atrial Fibrillation. Arrhythmia & electrophysiology review Chang, A. Y., Kaiser, D., Ullal, A., Perino, A. C., Heidenreich, P. A., Turakhia, M. P. 2014; 3 (3): 177-183

    Abstract

    Atrial fibrillation (AF) is one of the most common cardiac conditions treated in primary care and specialty cardiology settings, and is associated with considerable morbidity, mortality and cost. Catheter ablation, typically by electrically isolating the pulmonary veins and surrounding tissue, is more effective at maintaining sinus rhythm than conventional antiarrhythmic drug therapy and is now recommended as first-line therapy. From a value standpoint, the cost-effectiveness of ablation must incorporate the upfront procedural costs and risks with the benefits of longer term improvements in quality of life (QOL) and healthcare utilisation. Here, we present a primer on cost-effectiveness analysis (CEA), review the data on cost-effectiveness of AF ablation and outline key areas for further investigation.

    View details for DOI 10.15420/aer.2014.3.3.177

    View details for PubMedID 26835088

    View details for PubMedCentralID PMC4711535

  • Trial of Zolpidem, Eszopiclone, and Other GABA Agonists in a Patient with Progressive Supranuclear Palsy Case Reports in Medicine Chang, A. Y., Weirich, E. 2014; 2014: 5
  • Spatial organization of dendritic cells within tumor draining lymph nodes impacts clinical outcome in breast cancer patients JOURNAL OF TRANSLATIONAL MEDICINE Chang, A. Y., Bhattacharya, N., Mu, J., Setiadi, A. F., Carcamo-Cavazos, V., Lee, G. H., Simons, D. L., Yadegarynia, S., Hemati, K., Kapelner, A., Ming, Z., Krag, D. N., Schwartz, E. J., Chen, D. Z., Lee, P. P. 2013; 11

    Abstract

    Dendritic cells (DCs) are important mediators of anti-tumor immune responses. We hypothesized that an in-depth analysis of dendritic cells and their spatial relationships to each other as well as to other immune cells within tumor draining lymph nodes (TDLNs) could provide a better understanding of immune function and dysregulation in cancer.We analyzed immune cells within TDLNs from 59 breast cancer patients with at least 5 years of clinical follow-up using immunohistochemical staining with a novel quantitative image analysis system. We developed algorithms to analyze spatial distribution patterns of immune cells in cancer versus healthy intra-mammary lymph nodes (HLNs) to derive information about possible mechanisms underlying immune-dysregulation in breast cancer. We used the non-parametric Mann-Whitney test for inter-group comparisons, Wilcoxon Matched-Pairs Signed Ranks test for intra-group comparisons and log-rank (Mantel-Cox) test for Kaplan Maier analyses.Degree of clustering of DCs (in terms of spatial proximity of the cells to each other) was reduced in TDLNs compared to HLNs. While there were more numerous DC clusters in TDLNs compared to HLNs,DC clusters within TDLNs tended to have fewer member DCs and also consisted of fewer cells displaying the DC maturity marker CD83. The average number of T cells within a standardized radius of a clustered DC was increased compared to that of an unclustered DC, suggesting that DC clustering was associated with T cell interaction. Furthermore, the number of T cells within the radius of a clustered DC was reduced in tumor-positive TDLNs compared to HLNs. Importantly, clinical outcome analysis revealed that DC clustering in tumor-positive TDLNs correlated with the duration of disease-free survival in breast cancer patients.These findings are the first to describe the spatial organization of DCs within TDLNs and their association with survival outcome. In addition, we characterized specific changes in number, size, maturity, and T cell co-localization of such clusters. Strategies to enhance DC function in-vivo, including maturation and clustering, may provide additional tools for developing more efficacious DC cancer vaccines.

    View details for DOI 10.1186/1479-5876-11-242

    View details for Web of Science ID 000326447100001

    View details for PubMedID 24088396

    View details for PubMedCentralID PMC3852260

  • Center-surround vs. distance-independent lateral connectivity in the olfactory bulb FRONTIERS IN NEURAL CIRCUITS Kim, D. H., Chang, A. Y., McTavish, T. S., Pateland, H. K., Willhite, D. C. 2012; 6

    Abstract

    Lateral neuronal interactions are known to play important roles in sensory information processing. A center-on surround-off local circuit arrangement has been shown to play a role in mediating contrast enhancement in the visual, auditory, and somatosensory systems. The lateral connectivity and the influence of those connections have been less clear for the olfactory system. A critical question is whether the synaptic connections between the primary projection neurons, mitral and tufted (M/T) cells, and their main inhibitory interneurons, the granule cells (GCs), can support a center-surround motif. Here, we study this question by injecting a "center" in the glomerular layer of the olfactory bulb (OB) with a marker of synaptic connectivity, the pseudorabies virus (PRV), then examines the distribution of labeling in the "surround" of GCs. We use a novel method to score the degree to which the data fits a center-surround model vs. distance-independent connectivity. Data from 22 injections show that M/T cells generally form lateral connections with GCs in patterns that lie between the two extremes.

    View details for DOI 10.3389/fncir.2012.00034

    View details for Web of Science ID 000304625700001

    View details for PubMedID 22666190

  • Learning to live together: harnessing regulatory T cells to induce organ transplant tolerance. Yale journal of biology and medicine Chang, A. Y., Bhattacharya, N. 2011; 84 (4): 345-351

    Abstract

    The discovery of immune cells with regulatory effects has created considerable excitement for their potential use in inducing tolerance to transplanted tissues. Despite the fact that these cells possess essential functions in vivo, attempts to translate them into effective clinical therapies has proved challenging due to a number of unanticipated complexities in their behavior. This article provides a broad summary of research done to understand the largest of the regulatory cell subtypes, namely CD4+Foxp3+ Regulatory T cells (T(Regs)). Special attention will be paid to current and future difficulties in using T(Regs) clinically, as well as room for improvement and innovation in this field.

    View details for PubMedID 22180672

    View details for PubMedCentralID PMC3238321

  • Lateral connectivity in the olfactory bulb is sparse and segregated FRONTIERS IN NEURAL CIRCUITS Kim, D. H., Phillips, M. E., Chang, A. Y., Patel, H. K., Nguyen, K. T., Willhite, D. C. 2011; 5

    Abstract

    Lateral connections in the olfactory bulb were previously thought to be organized for center-surround inhibition. However, recent anatomical and physiological studies showed sparse and distributed interactions of inhibitory granule cells (GCs) which tended to be organized in columnar clusters. Little is known about how these distributed clusters are interconnected. In this study, we use transsynaptic tracing viruses bearing green or red fluorescent proteins to further elucidate mitral- and tufted-to-GC connectivity. Separate sites in the glomerular layer were injected with each virus. Columns with labeling from both viruses after transsynaptic spread show sparse red or green GCs which tended to be segregated. However, there was a higher incidence of co-labeled cells than chance would predict. Similar segregation of labeling is observed from dual injections into olfactory cortex. Collectively, these results suggest that neighboring mitral and tufted cells receive inhibitory inputs from segregated subsets of GCs, enabling inhibition of a center by specific and discontinuous lateral elements.

    View details for DOI 10.3389/fncir.2011.00005

    View details for Web of Science ID 000290153700001

    View details for PubMedID 21559072

  • Hydrophilic Graft Modification of a Commercial Crystalline Polyolefin J. Polym. Sci. Part A: Polym. Chem. Jihoon Shin, Andrew Y. Chang, Lacie V. Brownell, Ira O. Racoma, Coreen H. Ozawa, Ho-Yong Chung, Shufu Peng, Chulsung Bae 2008; 46: 3533-3545
  • Regioselective functionalization of high-molecular-weight crystalline polyolefins via C-H activation of methyl side group Polymer Preprints Hoyong Chung, Andrew Y. Chang, Ira O. Racoma, Coreen H. Ozawa, Chulsung Bae 2006; 47: 247-248