TO THE EDITOR:
Frías et al. report on the favorable effects of tirzepatide on glucose homeostasis. The authors also found that tirzepatide had relatively rapid and strong antihypertensive effects (as evidenced by a decrease from baseline in systolic blood pressure of 6.5 mm Hg in the group that received the 15-mg dose). A subgroup analysis involving the patients in the trial who had hypertension could be valuable. It would also be important to know whether the use of beta-blockers, angiotensin-converting–enzyme (ACE) inhibitors, or angiotensin-receptor blockers (ARBs) was similar in the trial groups and whether patients who were receiving these drugs at enrollment were allowed to continue taking them during the trial.
The antihypertensive effect of tirzepatide should not depend on the regulation of the insulin level; indeed, since insulin has been shown to stimulate both nitric oxide production and endothelin-1 secretion,1 its net hemodynamic effect on blood pressure is minimal.2 Moreover, insulin therapy can lead to microcirculatory disorders.3 Given the complex relationship linking GLP-1, endothelial dysfunction, and diabetes,4,5 it would be informative if the authors could provide data on endothelial function, inflammation, and oxidative stress.
Footnotes
No potential conflict of interest relevant to this letter was reported.
References
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