Arterial hypertension is essential (primary) in most cases. In 5-10% of cases hypertension is secondary to other conditions, including some hormonal disorders. The correct diagnosis and treatment of these disorders are extremely important for several reasons: secondary hypertension is more aggressive and can cause cardio-vascular complications; Proper treatment of the hormonal disorder leads to better control of blood pressure, with fewer drugs and in some cases even to cure hypertension.Situations in which we suspect a secondary cause of hypertension include:
- Treatment resistant hypertension: TA (blood pressure) is not controlled with 3 antihypertensives including a diuretic or TA it is controlled with 4 or more antihypertensives.
- Hypertension diagnosed at a young age, under 30, or at over 50 years of age.
- Drug-induced hypertension
- Hypertension with ocular, renal, cerebrovascular, cardio-vascular complications
- Malignant / accelerated hypertension
Causes of secondary hypertension:
- Sleep apnea syndrome
- Renal causes:
- Renal parenchymal disease
- Renal artery stenosis
- Hormonal / endocrinological causes:
- Primary hyperaldosteronism (Conn syndrome)
- Cushing’s syndrome
- Hypothyroidism / Hyperthyroidism
- Primary hyperparathyroidism
- Other mineralocorticoid excess syndromes
- Congenital adrenal hyperplasia
- Medications (non-steroidal anti-inflammatory, contraceptive), smoking and alcohol
- Aortic coarctation
Primary hyperaldosteronism is produced by a tumor, in most cases benign, of the adrenal glands that secrete excessive amounts of aldosterone. This is a hormone involved in blood pressure control. The prevalence of this condition is reported in 8-20% of the hypertensive population. The first step in the evaluation is to determine aldosterone and renin concentration in the blood. If the screening test is positive, the next step is the confirmation with suppression tests, which uses sodium chloride either orally or intravenously. The treatment can be medicinal or surgical.
There are several rare syndromes characterized by excess mineralocorticoids (aldosterone, corticosterone, hydroxycorticosterone) and caused by genetic mutations.
Cushing’s syndrome is characterized by an excess of cortisol produced by a tumor of the adrenal glands or a pituitary adenoma. Cushing’s syndrome is a rare condition that is manifested by weight gain especially in the upper body, proximal muscle weakness (thighs), increased hair loss, acne, diabetes and hypertension difficult to control. There are 3 screening tests for this syndrome: salivary cortisol, free urinary cortisol, and 1 mg dexamethasone suppression test. After the biochemical confirmation of the diagnosis, tumor localization tests are performed, usually pituitary MRI and adrenal glands.
Hypothyroidism and hyperthyroidism are functional disorders of the thyroid gland, characterized by the insufficiency and excess of thyroid hormones. Manifestations of hypothyroidism include weight gain, asthenia, voice change, cold intolerance, constipation, decreased heart rate, memory impairment. Hyperthyroidism causes weight loss, palpitations, agitation, anxiety, hot intolerance, tremor, muscle weakness, increased heart rate, heart rhythm disorders. Both can cause heart failure and high blood pressure. TSH is the test that best reflects the overall thyroid function. The treatment of hypothyroidism is done with Levothyroxine and that of hyperthyroidism with anti-thyroid drugs, radioactive iodine or thyroidectomy.
Pheochromocytoma is a tumor of the adrenal glands that secretes adrenaline and / or norepinephrine in excess. Patients have episodes of headache, sweating and palpitations associated with hypertensive flares; these episodes usually take 30-40 minutes. Hypertension is severe and can be chronic and in 25-50% of cases it is paroxysmal. Pheochromocytoma may be sporadic or may be part of various syndromes such as multiple endocrine neoplasia, neurofibromatosis, Von Lippel Lindau syndrome, etc. The screening test involves measuring the metabolites of adrenaline, noradrenaline and in some cases dopamine in blood or urine. After biochemical confirmation, the tumor with CT or MRI of adrenal glands is localized. The treatment is surgical and is done after obtaining an adequate blood pressure control and after hydration.
Primary hyperparathyroidism is caused by a generally benign tumor of the parathyroid glands. Patients with this condition have elevated levels of calcium in the blood and may be asymptomatic or they may have nephrolithiasis (kidney stones), decreased bone density, bone fractures, constipation, excessive fatigue, depression but also high blood pressure. Determining the level of calcium, phosphorus, vitamin D and parathyroid hormone in the blood helps to diagnose. Treatment depends on symptomatology and involves surgical resection of parathyroid adenoma.
Acromegaly is an extremely rare condition caused by a pituitary adenoma. Acromegaly is characterized by an excess of growth hormone. In childhood and adolescence, this condition is called gigantism . In adults, a high level of growth hormone causes extremities to overgrow, tightening of face features with orbital bone prominence, increased jaw, excessive sweating, intestinal polyps but also high blood pressure and cardiac hypertrophy. The first-line treatment is surgical and leads to a significant improvement in blood pressure control.
Congenital adrenal hyperplasia : is caused by defects of the enzymes involved in the synthesis of adrenal hormones (aldosterone, cortisol, sex hormones). Depending on the enzyme defect, the manifestations may be: high blood pressure, genital ambiguity (hermaphroditism), adrenal insufficiency. Diagnosis involves the measurement of adrenal hormones in the blood. Treatment varies according to the cause and the clinical manifestations.
Article made by Dr. Cristina Bloț – specialist in endocrinology.