Neurological causes of orthostatic hypotension (OH) stem from damage to the autonomic nervous system (ANS), which controls involuntary functions like blood pressure, leading to failure in constricting blood vessels when standing; common culprits include Parkinson's disease, Multiple System Atrophy (MSA), Dementia with Lewy Bodies, Pure Autonomic Failure, and autonomic neuropathies from diabetes or autoimmune issues, all disrupting the brain's ability to signal for increased heart rate and vessel constriction against gravity.
It is caused by failure of noradrenergic neurotransmission that is associated with a range of primary or secondary autonomic disorders, including pure autonomic failure, Parkinson's disease with autonomic failure, multiple system atrophy as well as diabetic and nondiabetic autonomic neuropathies.
A myriad of neurologic disorders including multiple sclerosis, spinal cord injury, and tabes dorsalis (syphilitic myelopathy), can cause autonomic dysfunction and result in symptomatic hypotension.
They might include:
If a patient develops OH upon standing, an increase in HR < 15 bpm suggests a diagnosis of nOH, whereas patients with non-neurogenic OH will typically demonstrate an increase in HR of 15 bpm within 3 minutes of standing.
When a patient's neurologist and cardiologist work together as a team, they can ensure that nOH is treated safely and effectively, and patients may find their nOH symptoms are better managed. nOH can be treated with lifestyle changes such as drinking more water, eating more salty food, or gentle exercises.
POTS and orthostatic hypotension could easily be mistaken for one another. Both conditions may be referred to as types of “orthostatic intolerances.” The main difference between these two similar conditions is: Orthostatic hypotension is a drop in blood pressure due to a change in position.
This damage can cause significant impact to areas of the autonomic nervous system such as the heart, circulatory system and sweat glands. The most frequent cause of autonomic neuropathy is diabetes. However, other health conditions, such as viral or bacterial infections, or certain medications can also cause it.
Difficulty swallowing or loss of gag reflex. Dizziness or fainting. Hoarseness, wheezing or loss of voice.
Nerve Compression: Misalignment in the neck can pinch the nerves that control blood pressure regulation. This interference can result in lower-than-normal blood pressure, as the body's ability to maintain a stable blood pressure is compromised.
Autoimmune Addison disease can lead to a life-threatening adrenal crisis, characterized by vomiting, abdominal pain, back or leg cramps, and severe hypotension leading to shock.
What are neurological symptoms that should never be ignored? Key symptoms to watch for include sudden severe headaches, unexplained numbness or tingling, vision changes, cognitive decline, muscle weakness, tremors, balance problems, speech difficulties, and seizures.
Orthostatic hypotension is defined by a significant drop in blood pressure (≥ 20 mmHg systolic or ≥ 10 mmHg diastolic) within 3 minutes of standing. This sudden dip can reduce blood flow to the brain, leading to dizziness or fainting. In contrast, people with POTS typically maintain stable blood pressure when upright.
Orthostatic hypotension is often caused or made worse by dehydration. Other causes include diabetes, heart disease, and nervous system problems. Many medications cause orthostatic hypotension. Treatment can involve adjusting medicines and increasing fluid intake.
Case reports of patients with autoimmune-related OH have been published. Furthermore, 20% of POTS patients have a diagnosis of a coexisting autoimmune disease, including but not limited to Hashimoto's thyroiditis, celiac disease, Sjogren's disease, rheumatoid arthritis, and systemic lupus erythematosus [5,6,7].
Medication Causes of Orthostatic Hypotension
Compression or irritation of the vagus nerve can cause severe pain in the neck and shoulders, or induce headaches, dizziness, and brain fog. Additionally, since this nerve is complicated and wandering in nature, many other crucial bodily systems may also be disrupted if it sustains damage.
Before you faint due to vasovagal syncope, you may experience some of the following symptoms:
If the upper roots, C2, C3 and C4, are irritated they may complain of occipital headaches, often typical of migraine, with pain radiating to the eyes and behind the ears, blurring of vision, dizziness and nausea especially when attempting to lie down, numbness of the side of the neck, tension and “knots” in the neck ...
Symptoms of autonomic neuropathy can include:
Vagus nerve dysfunction can manifest in surprisingly diverse ways. Common symptoms include chronic neck and shoulder pain, unexplained dizziness, digestive problems, anxiety, difficulty swallowing, voice changes, and persistent fatigue.
Acute pandysautonomia is a rare disease defined as acute widespread and severe sympathetic and parasympathetic failure and sparing of somatic nerve fibers. The causes of this syndrome are often an autoimmune disease leading to autonomic ganglionopathy.
Autoimmune autonomic ganglionopathy is a rare disorder that affects your nervous system. In AAG, your immune system attacks your autonomic nervous system. You may experience fainting, low blood pressure upon standing or gastrointestinal symptoms.
Orthostatic hypotension signs and symptoms include: Lightheadedness or dizziness upon standing. Blurry vision. Weakness.
Common differential diagnoses for POTS include thyroid disorders and thyrotoxicosis, inappropriate sinus tachycardia, pheochromocytoma, anxiety, dehydration, infection, hypoadrenalism, and medication-induced tachycardia.