Document wqBbjv5BengEEZw8EYaq72VNd

/y\ Veterans vVw Administration October 15, 1984 In Reply Refer To: 561/15 David E. Weil, Ph.D. U.S. Environmental Protection Agency Environmental Criteria & Assessment Office (MD-52) Research Triangle Park, North Carolina 27711 Dear Dr. Weil: Thank you for the opportunity to address the plausibility that blood lead correlates with blood pressure and that hypertension correlates with stroke and heart attacks as suggested in the abstract by Pirkle et al (1) and the memorandum prepared by 3oel Schwartz on "Blood lead and blood pressure" for Docket EN-84-05. While I am unable to evaluate the statistical models used for the analyses, I believe the conclusion that "the relationship of systolic and diastolic blood pressure to blood lead levels was statistically significant", is entirely consistant with accumulated evidence on the role of lead in cardiovascular disease. Dur own studies indicate that unrecognized lead absorption is an important contributor to hypertensive renal disease in subjects usually considered to have "essential" hypertension (2). While the patients we studied had considerably greater exposure to lead than was encountered in the NHANE5 II population, their excessive body lead stores were superimposed upon a background of lead absorption which rendered them vulnerable to the severe medical complications. Although our study focused on hypertensives with renal failure, it is clear that there must be another population of lead induced hypertensives without renal failure who will develop renal failure later in the course of their disease. Moreover, present knowledge indicates that hypertension represents the upper end of continuum of blood pressure levels in the general population. There is every reason to believe that this continuum extends down to blood pressure levels presently considered to be in the "normal" or "safe" range. It "is apparently - the--impaet--of--environmental -lead--in thir .mmip .that hsts^-bmm identified in the NHANtS~H analysis prest-mled 'by^Pirfcel ct al-. Once blood pressure rises to abnormal levels, all the complications of hypertensive disease can be anticipated including stroke and heart disease. It is noteworthy that the cost analysis presented by Joel Schwartz omits any mention of the contribution of lead to the End-Stage Renal Disease (ESRD) program. Chronic dialysis and transplant programs presently cost the United States government over two billion dollars a year. While the contribution of lead nephropathy to this financial burden has not been precisely defined, lead may be responsible for as much as half of those N36694 DUP050298717 patients presently believed to require ESRD care because of hypertensive nephrosclerosis. References: 1. Pirkle 3L, Schwartz 3H, Landis 3R, & Harlon NR. The relationship between bloodlead levels and blood pressure and its cardiovascular risk implications. Am. 3. Epidemiology, in press. 2. Batuman V, Landy E, Maesaka 3K, & Wedeen RP. Contribution of lead to hypertension with renal impairment. N. Engl. 3. Med. 309:17-21, 1983. Sincerely, Ric h a r d p . w e d e e n , m.d . Professor of Medicine UMDN3/New 3ersey Medical School Associate Chief of Staff for Research & Development TtEH 0350089 DUP050298718