Fig. 3
From: Screening and treatment of hypertension in older adults: less is more?
The hypothetical causal relationship between blood pressure (BP) and related adverse health outcomes or mortality according to different scenarios is depicted in these graphs. (I) Usually, BP has a causal effect on adverse health outcomes (O) and death (D). (II) The relationship can be confounded by unmeasured factors (C), which have an effect on both BP and the risk of adverse health outcomes. (III) In a situation of reverse causality, some conditions, which can be initially caused by high BP, evolve to become the cause of low BP