Differential Diagnosis for Orthostatic Hypotension in an Older Patient with Newly Diagnosed Hypertension
- Single Most Likely Diagnosis
- Dehydration: This is a common side effect of Chlorthalidone, a thiazide-like diuretic, which can lead to orthostatic hypotension due to volume depletion.
- Other Likely Diagnoses
- Autonomic dysfunction: Older adults may have underlying autonomic nervous system dysfunction, which can be exacerbated by antihypertensive medication, leading to orthostatic hypotension.
- Overmedication: The initiation of antihypertensive therapy, especially with a diuretic like Chlorthalidone, can sometimes result in an excessive decrease in blood pressure, particularly in patients who are sensitive or have a low blood volume.
- Do Not Miss Diagnoses
- Cardiac causes: Such as cardiac tamponade or severe cardiac dysfunction, which can lead to orthostatic hypotension due to decreased cardiac output.
- Bleeding or significant blood loss: Internal bleeding or significant external blood loss can lead to hypovolemic shock, presenting with orthostatic hypotension.
- Adrenal insufficiency: Although rare, this condition can cause orthostatic hypotension due to the lack of cortisol and aldosterone, which are crucial for maintaining blood pressure.
- Rare Diagnoses
- Pheochromocytoma: A rare tumor of the adrenal gland that can cause orthostatic hypotension due to the intermittent release of catecholamines, which can lead to volume depletion and autonomic dysfunction.
- Multiple system atrophy (MSA): A rare neurodegenerative disorder that affects the autonomic nervous system, leading to severe orthostatic hypotension.
- Dopamine beta-hydroxylase deficiency: An extremely rare genetic disorder that affects the production of norepinephrine, leading to severe orthostatic hypotension.