It is a curious medical fact that people who suffer from kidney disease are not only at great risk from kidney failure requiring dialysis or transplantation, but are more likely than most to die from heart problems.
Over 10 million Americans suffer from Chronic Renal Insufficiency (CRI), a disease that, for many sufferers, leads to death from cardiovascular complications related to high blood pressure before their kidney disease progresses to end-stage.
To understand the progression of CRI, researchers at the University of Pennsylvania School of Medicine will track the health of 3,000 CRI sufferers from seven clinical sites across the country.
The National Institute of Diabetes and Digestive and Kidney Disease (NIDDK) of the National Institutes of Health has committed over $40 million to begin the project and see it through the first seven years of operation.
The funding will go to seven clinical centers, including Penn, and one scientific data-coordinating center. The latter, also based at Penn, will coordinate the scientific conduct of the study, analyze all study data, and disseminate their findings.
Penn will receive about $17 million of the grant to fund both the clinical and data coordinating centers on its campus.
"We will serve as the nerve center of the operation, collecting data from the individual centers and coordinating the scientific efforts to sort out the long-term factors that put CRI sufferers at greater risk," said Harold I. Feldman, MD, associate professor of medicine and epidemiology at the Penn Center for Clinical Epidemiology and Biostatistics (CCEB) and principal investigator of the CRI Scientific and Data Coordinating Center (CRI-SDCC).
Dr. Feldman is joined by co-principal investigator J. Richard Landis, PhD, professor of biostatistics also at the CCEB.
CRI is an important risk factor for end stage renal disease (ESRD). In 1999, over 300,000 patients were treated for ESRD in the United States, incurring $11.3 billion in Medicare payments. Among patients with end-stage kidney disease, heart-related mortality rates are 10 to 20 times that of the general population -- and account for nearly half of all deaths in hemodialysis patients older than 20.
As one of the nation's leading centers for epidemiological and biostatistical research, the Penn group will use its scientific and logistical expertise to coordinate the multi-institutional effort using web-based data/specimen collection, quality assurance programs, and data analysis.
"It is a massive undertaking; some have taken to calling this study the 'Framingham Study' of kidney disease," said John W. Kusek, PhD, director of the Clinical Trials Program in the NIDDK Division of Kidney, Urologic, and Hematologic Diseases.
Since 1948, the Framingham Study has followed the health of over 5,000 volunteers from Framingham, Massachusetts, in order to study the long-term progress of cardiovascular disease.
"Unlike Framingham, this effort will study a less homogeneous patient population, incorporating the ethnic and racial groups in which CRI has become more prevalent."
Because CRI is found in disproportionately high numbers among minority groups, the researchers will make special efforts to ensure that minorities are adequately represented in the study.
Each of the seven clinical centers will recruit people with mild to moderate kidney disease and track how kidney and heart disease progress over time, while at the same time ensuring that the subjects receive the current standard of care for their disease.
About one-half of the study participants will also suffer from diabetes, the cause of about 50% of the cases of ESRD. The clinical centers plan to complement -- but not replace -- the subjects' current source of health care.
"In each patient, we plan to take a comprehensive look at the state-of-the-moment in their health," said Raymond R. Townsend, MD, professor of medicine in Penn's Renal-Electrolyte and Hypertension Division, and Director of one of the seven clinical centers soon to be opened at the Hospital of the University of Pennsylvania (HUP). "Over time, these discrete moments, taken from the best clinical technologies available, will form a look at kidney disease that is complete from every possible angle, be it genetic, physical, environmental, or biochemical."
The clinical center at HUP will begin recruiting study participants late in 2002, as will centers at Case Western Medical Center, University of Illinois, Johns Hopkins University - University of Maryland, Kaiser Permanente-San Francisco, University of Michigan and Tulane University.
Lifestyle factors will also be examined, including diet, exercise, smoking and drinking. Quality of life will also be studied over time. The researchers will also give close scrutiny to two factors that have been shown to affect the progression of CRI -- the control of blood pressure and management of blood sugar in patients with diabetes.
"We expect that what we learn here will serve patients with CRI long into the future," said Feldman, "This study is sure to stimulate new avenues of research, shaping both our understanding of the mechanisms of disease as well as the development of new clinical interventions aimed at reducing the burden of end-stage renal disease in the U.S." - By Greg Lester
[Contact: Greg Lester]