What Is the Most Common Cause of Secondary Hypertension?: An Interdisciplinary Discussion

Purpose of Review Traditional statements in medical textbooks pointed that 90 to 95% of cases of hypertension is essential or primary. However, secondary hypertension seems to be common in those patients with resistant forms of hypertension. Appropriate investigation and treatment may have prognostic impact but frequently hypertension remission did not occur raising concerns about the real meaning of secondary hypertension. Here, we provided an interdisciplinary and critical discussion comprising an endocrinologist, a nephrologist, and a cardiologist with expertise in resistant hypertension. We reviewed the literature approaching each one of the recognizable cause of hypertension. Recent Findings Recent studies pointed that the most common causes of secondary hypertension are those who overall responses to their treatments do not promote hypertension remission including obstructive sleep apnea (OSA), chronic kidney disease, renovascular hypertension and primary aldosteronism. The authors raised concerns regarding the lack of inclusion of obesity by several societies as a formal cause of hypertension considering not only the biologic plausibility but also the huge impact of weight loss therapies such as bariatric surgery on hypertension remission. In contrast, there is no discussion that a very rare condition-namely pheochromocytoma-is the most "typical" cause of hypertension by promoting hypertension remission in the majority of patients after surgical procedure. Hypertension is a complex condition with multiple environmental and genetics interactions. In clinical practice, it is challenging to prove causality in hypertension. Common conditions largely acceptable as causes of hypertension (OSA, chronic kidney disease, renovascular hypertension, and primary aldosteronism) frequently occur in a setting of an established hypertension background and therefore do not promote hypertension remission in a significant proportion of patients. If obesity becomes largely accepted by several societies as a secondary form of hypertension, this pandemic condition will be certainly the most common cause of hypertension.