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Assessing hypertension therapies: randomization or confounding by indication?

Findings from a large, international study comprising 4.9 million people with mild hypertension suggest that thiazide and thiazide-like diuretics might be more effective and safer than other first-line antihypertensive drugs. However, the study was not randomized, and the findings might be explained by a phenomenon known as ‘confounding by indication’.

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Fig. 1: One pill daily for first-line treatment of hypertension.


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Correspondence to Sverre E. Kjeldsen.

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Competing interests

S.E.K. has received lecture honoraria from Merck KGaA, Merck & Co., Sanofi and Takeda, and consulting honoraria from Takeda. I.O. declares no competing interests.

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Kjeldsen, S.E., Os, I. Assessing hypertension therapies: randomization or confounding by indication?. Nat Rev Cardiol 17, 73–74 (2020).

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