Presently the term “primary hyperaldosteronism” is used to describe Conn syndrome and other associated conditions involving an aldosterone-secreting adenoma.
Conn’s syndrome was first described by the American endocrinologist Jerome W. Conn in 1955, in a patient who had an aldosterone-secreting adenoma.
Presently, the term “primary hyperaldosteronism” is used to describe Conn syndrome and other associated conditions, such as adrenal hyperplasia. In a population with hypertension in the United States, prevalence for primary hyperaldosteronism, and specifically for Conn syndrome, is estimated to be around 0.05-2% and 0.03-1.2% respectively.
The condition occurs twice as commonly in women as in men. It is mainly seen in those between 30-60 years of age.
Primary hyperaldosteronism can be inherited in some people in an autosomal dominant fashion. It is caused by the increased secretion of the hormone aldosterone from the adrenal glands. Aldosterone acts on the kidneys resulting in an increase in sodium and lowering of potassium levels in the blood, and increases the alkalinity of the blood. Primary hyperaldosteronism has two major subtypes: (1) unilateral alderosterone producing adenoma or Conn syndrome (50-60% of all cases), and (2) bilateral adrenal hyperplasia (40-50% of all cases). In bilateral adrenal hyperplasia, aldosterone levels increase with changes in posture.