In conjunction with our tenure as the USRDS Coordinating Center, we served as the Special Studies Center for Cardiovascular Disease. Our research continues to focus on patients with kidney disease and their outcomes following clinical and pharmacological cardiovascular interventions.
Our expertise in kidney disease is evidenced by our 14-year tenure as the Coordinating Center for the U.S. Renal Data System (USRDS). Through our observational studies, we have worked to improve awareness and treatment of chronic kidney disease and assure that renal replacement therapy is delivered in a safe and effective manner.
In addition to outcomes analyses on end-stage renal disease patients who receive a renal transplant, we currently administer the Scientific Registry of Transplant Recipients (SRTR, www.srtr.org), evaluating the status of solid organ transplants in the United States.
Members of our group conduct and coordinate health services research. We provide expert assistance on epidemiological and clinical study design, evaluate quality of care, assess the use of pharmaceuticals, and analyze major diseases and the economic burden they create.
Our research in the area of oncology has provided valuable insights into the incidence and effects of cancer in patients with end-stage renal disease. We continue to evaluate rates of cancer and its effect on this vulnerable population.
The United States healthcare system is in a constant state of flux. We have the expertise to evaluate changes in the delivery of healthcare and the effects these changes have on patient well-being.
CDRG is an interdisciplinary, clinician-guided biomedical research group committed to the investigation of chronic illnesses to improve public health. We seek to heighten awareness of issues and treatment concerns, affect decisions about patient care, and improve clinical outcomes worldwide. As a nonprofit organization, our strength rests on the integrity of our research practices and our commitment to patient health and well-being.
We evaluate healthcare and healthcare systems and identify trends. In cooperation with corporate, academic, and government partners, our team conducts research into clinical practices and treatment outcomes.
Clinical trial support
Data privacy & protection
Modeling & analyses
Reports & presentations
With the oversight of the Minneapolis Medical Research Foundation’s Institutional Review Board, we provide clinical trial support to pharmaceutical, biotechnical, and biochemical companies, health plans, universities, and federal and state government agencies:
• study design
• establishment of enrollment criteria
• sample size calculations
• data merging and processing
• design and construction of data collection tools, including forms and web interfaces
• enrollment and data collection
• biostatistical analyses and data interpretation
• outcomes analyses
• reports, manuscripts, and conference presentations
We are committed to ensuring both the privacy of patient records and the integrity of our data and data systems, with security policies and infrastructure framed by requirements of the Privacy Act and HIPAA rules. Towards that end, we have developed a comprehensive information-system security plan that includes the following:
• Oversight by the Minneapolis Medical Research Foundation’s Institutional Review Board
• Employee training in and signed commitment to the Privacy Act and HIPAA
• Encrypted patient-identifiable data
• Staff who track data from initial request to study completion, assuring security, confidentiality, and regulation compliance, and tracking systems to monitor the transaction activities of research files
• Limited, password-protected access to servers and networks, restricted access to computing equipment and data storage media, and secure, restricted-access physical space protected by electronic locks and cipher locks
• Firewalls to block unauthorized computer system access from the Internet, and virus detection software for each desktop and laptop on the network
• Regularly scheduled data backups, off-site storage to prevent data loss due to unexpected events, and archiving systems to preserve programs, datasets, study methods and results, abstracts, manuscripts, and data reports
Our theoretical biostatisticians develop methods and study designs for clinical and economic analyses, with experience that includes the following:
• multi-state models
• marginal structural models
• measurement issues in natural history studies; bias adjustment in observational studies
• structural equation modeling
• modeled rates
• methods to assess and account for bias
• propensity scores
• instrumental variable analyses
• Bayesian techniques
• long-term cohort studies
Our current work includes the following topics:
• anemia, epoetin use, and attainment of target hemoglobin levels
• Bayesian techniques to advance methods of healthcare provider profiling
• bone and mineral metabolism medications and morbidity, mortality, and economic outcomes in dialysis patients
• cardiac disease in the general Medicare population
• CKD, anemia, comorbidity, and related trends in incidence and prevalence
• development of Bayesian hierarchical spatial models capable of showing geographic patterns
• interaction of anemia, chronic kidney disease, and congestive heart failure
• post-myocardial infarction death rates in patients with varying levels of CKD
• projections of future numbers of ESRD/Dialysis patients
• propensity scores as predictors of actual hemoglobin levels
• total diabetes burden in the U.S. ESRD population
• use of the instrumental variable approach to adjust biased effects of diabetic care on outcomes among aged populations
• use of marginal structural models to assess the impact of erythropoietin and hemoglobin on mortality
• use of modeled rates to improve the stability in the standard incident and prevalence rates
• use of structural equation modeling to assess direct and indirect effects of hemoglobin level on medical costs in ESRD patients
We produce project-specific, customized data reports interpreting and summarizing our findings for our research sponsors.
We also regularly publish our research in peer-reviewed journals, including the New England Journal of Medicine, the Journal of the American Society of Nephrology, the American Journal of Kidney Disease, Kidney International, the Journal of the American College of Cardiology, the American Journal of Transplantation, Circulation, and JAMA.
Members of our group present findings at national and international meetings, including the American Society of Nephrology, the National Kidney Foundation, and the European Dialysis and Transplant Association.
Our investigators, experienced with observational studies using large administrative databases and with clinical trials, are also clinical specialists in pharmacy, end-stage renal disease, chronic kidney disease, cardiovascular disease, clinical cardiology, and diabetes, and have additional expertise in health policy and epidemiology.
Allan J Collins, MD, FACP | Nephrology
Dr. Collins, the Director of CDRG and Professor of Medicine at the University of Minnesota, has more than 30 years of experience in nephrology and ESRD treatment. His clinical experience and research have focused on acute and chronic care of ESRD patients and prospective and retrospective clinical studies on dialysis techniques and associated outcomes. He has also worked extensively with high-efficiency dialysis and therapy prescription, the technical elements of dialysis, billing systems (ICD-10 and CPT-4 claims elements), and computer systems and operations.
Charles A Herzog, MD | Cardiology
Dr. Herzog is a cardiologist at Hennepin County Medical Center and Professor of Medicine at the University of Minnesota. He has served as the cardiology consultant to the ESRD program at HCMC since 1985, and as the director of the cardiac ultrasound laboratory since 1997. His research includes cardiovascular outcomes in patients with CKD; survival of ESRD patients after acute myocardial infarction, coronary revascularization, valvular heart surgery, and bacterial endocarditis; and the epidemiology of sudden cardiac death in dialysis patients.
Bertram L Kasiske, MD | Transplantation
Dr. Kasiske is Professor of Medicine at the University of Minnesota and Director of the Scientific Registry of Transplant Recipients. He also serves as Director of the Division of Nephrology at Hennepin County Medical Center.
Robert N Foley, MB | Nephrology
Dr. Foley, a practicing nephrologist, has extensive experience with several domains of outcomes research, including large administrative datasets, classic prospective epidemiological studies predicated on primary data collection, studies with probabilistic survey designs, like NHANES, and multicenter randomized clinical trials. He also has an abiding interest in novel study designs, and has published extensively on logical approaches to risk hierarchies as they pertain to future screening guidelines.
James Wetmore, MD, MS | Nephrology
Dr. Wetmore is currently investigating the association of cardiovascular outcomes in chronic dialysis patients using large administrative databases (e.g., Medicare and Medicaid). He is the PI on an NIDDK K23 examining the benefits and risks of warfarin anticoagulation for stroke prevention in dialysis patients with chronic atrial fibrillation, and was key personnel on a grant investigating the association between cardioprotective antihypertensive medication use and outcomes in dialysis patients. He has also authored numerous publications on geographic variations and racial disparities in dialysis outcomes in dialysis.
Ajay K Israni, MD, MS | Transplantation & nephrology
Dr. Israni has extensive experience in conducting epidemiology studies in the area of solid organ transplantation, particularly with use of administrative datasets such as OPTN/SRTR data. He has conducted epidemiology research and published in the areas of kidney, kidney-pancreas, liver, and heart transplantation, and was awarded the Young Investigator Award for the American Transplant Congress in 2004. He currently serves as Deputy Project Director for the Scientific Registry of Transplant Recipients (SRTR).
CDRG collaborates with additional physician investigators both within and outside of the Hennepin Health System for a comprehensive clinical perspective on our projects and programs.
Our investigators, experienced with observational studies using large administrative databases and with clinical trials, are also clinical specialists in pharmacy, end-stage renal disease, chronic kidney disease, cardiovascular disease, clinical cardiology, diabetes, and with additional expertise in health policy and epidemiology.
Wendy L St. Peter, PharmD | Pharmacoepidemiology
Dr. St. Peter is a Professor of Pharmacy at the University of Minnesota, and has more than 23 years experience in nephrology pharmacy practice. Her research includes work on the clinical and cost impact of medications for bone and mineral disorders in chronic kidney disease patients, Medicare Part D enrollment and medication use patterns, and the effect of medications and medication therapy management on these patients. She served on the Technical Expert Panel for the Center for Medicare and Medicaid Services for the ESRD Outpatient Medications Project, and was a member of the Drug Utilization Review Board for the Minnesota Medicaid Program.
David T Gilbertson, PhD | Biostatistics & epidemiology
Dr. Gilbertson is a biostatistician experienced in the use of large and merged data sets. His current professional interests include the application of multi-state models to observational epidemiologic analyses, the use of Marginal Structural Models to assess the impact of time-varying covariates in the presence of time-varying confounders, the development of methods to assess and account for bias in observational epidemiologic analyses, the use of propensity scores in observational epidemiologic studies, and the use of instrumental variables in observational epidemiologic studies.
Jon J Snyder, PhD, MS | Transplantation
Dr. Snyder oversees epidemiologic investigations of the renal transplant population. He has worked extensively with data from the Organ Procurement and Transplantation Network and with administrative and claims databases. His recent research has focused on outcomes modeling in the renal transplant population. He served as co-investigator on the "Predicting Outcomes in Renal Transplantation" (PORT) study, which collated and analyzed data on more than 35,000 renal transplant patients from 14 programs in 9 countries, and directs analytic operations of the North Central Donor Exchange Cooperative.
Craig Solid, PhD | Health economics & nephrology
Dr. Solid has extensive training in the fields of biostatistics and health economics, and experience with a variety of analyses. These include cost-effectiveness and cost-benefit analyses, Heckman-correction techniques to account for selection bias, data transformation, survival models, and instrumental variable techniques. His experience includes studies in the clinical areas of anemia, diabetes, cardiovascular disease, dementia, and oncology.
Jiannong Liu, PhD | Biostatistics & methodology
Dr. Liu’s research interest is in the development of statistical methodology for observational data analyses among kidney disease patients, with an emphasis on disease mapping, health care profiling, comorbidity burdens, bias correction, and clinical outcomes analyses. He has developed an ESRD comorbidity scoring system, Bayesian Standardized Mortality Ratio methods, and additional modified Bayesian approaches. Dr. Liu has published more than 40 peer-reviewed journal articles, and is an editorial board member for Kidney International and The Scientific World Journal, Nephrology.
Shuling Li, PhD | Cancer epidemiology
Dr. Li has thorough knowledge and valuable experience in using Medical claims data, applying statistical methods in medical research, and designing/conducting epidemiologic studies. Her research interests center on cardiovascular epidemiology, cancer epidemiology, and the late effects of cancer therapy, in particular, cardiotoxicity and nephrotoxicity of chemotherapy in cancer survivors.
Suying Li, PhD | Health Policy & economics
Dr. Li has broad experience in health economics and biostatistics methodology, including log-transformed regression models with smearing estimates, multilevel mixed-effects regression models, survival models, and instrumental variable techniques. As an NIH-funded health economist, she is also skilled in the use of cost data. She has more than 60 lead author and co-author publications in peer-reviewed journals, addressing clinical outcomes and Medicare expenditures in dialysis patients, CKD risk factors and outcomes in populations at high risk for CKD, and diabetes care and related outcomes.
Akeem Yusuf, PhD | Pharmacoepidemiology
Dr. Yusuf began his career as a hospital pharmacist focused on medication use in ambulatory care settings. Since 2008, he has transitioned to research activities related to understanding the scientific and humanistic bases for understanding and influencing medication use, non-use, and misuse. He has employed survey research, content analysis, and secondary database analysis to address these issues at the individual patient level, specific disease level, and population level. He has an active interest in medication adherence and comparative effectiveness research.
Eric Weinhandl, MS | Peer Dialysis Network
Mr. Weinhandl is an epidemiologist with interests in pharmacoepidemiology, primarily as it relates to patients with end-stage renal disease and to the Medicare Part D prescription drug benefit; benefits and risks of home dialysis modalities; the etiology and treatment of anemia due to chronic kidney disease; and methods for the control of confounding in comparative effectiveness research with observational data. He serves as lead epidemiologist for the Peer Dialysis Network.
Allan J Collins, MD, FACP | Director, CDRG * David T Gilbertson, PhD | Co-Director, CDRG * Adrine Chung, MBA | Director of Operations * Stephan Dunning, MBA | Director, Business Development * Shu-Cheng Chen, MS, MPH | Director of Data Systems & IT
914 south 8th st., suite s4.100 | minneapolis mn | 55404
612 873 6200 | www.cdrg.org
CHRONIC DISEASE RESEARCH GROUP