Ergul S, Parish DC, Puett D, Ergul A
Racial differences in plasma endothelin-1 concentrations
in individuals with essential hypertension
Hypertens
(Oct) 28:652-655 1996

Hypertension among blacks is more prevalent and is associated with
more LVH, ESRD, stroke, and death. The reasons for this remain
unclear. Endothelin-1 is a hypertensive peptide which may be
involved in several types of hypertension. It's surprising that no
one has looked at endothelin-1 levels in blacks vs. whites. This
paper does, and finds a huge difference! Whereas ET-1 levels were
similar in normotensive blacks and whites, in hypertensive blacks,
mean plasma levels were about 11-12 nmol/L vs. 3-4 nmol/L in
hyperensive whites.
Comment: The problem with this study is that there may
have been a selection bias towards black hypertensives with more
severe hypertension or with more end-organ damage. Surprisingly, such
information was not analyzed in detail in this small study. For
example, it appears that more whites than blacks were on medication,
and the paper does not even give the mean BP levels in the patient
sample broken down by blacks vs. whites, nevermind data on GFR, LVH,
duration of hypertension, etc. The only things tested for were
hypertension (yes/no, apparently), race, age and sex. These
weaknesses leave us with intriguing preliminary data, from which
causality certainly cannot be inferred. (John T. Daugirdas, M.D.,
University of Illinois at Chicago)
The text of the original abstract is available from the AHA
at:
this site .