Mild dysfunction in the autonomic nervous system (ANS), also called mild dysautonomia is commonly comorbid with all primary headaches (migraine, TTH, NDPH). The ANS controls those body functions that we consciously have no control over, such as breathing, blood pressure regulation, heart rate regulation, digestion/GI motility, temperature regulation, sweating, or nervous system over-stimulation.
Common causes for dysfunction in the ANS are diabetes, peripheral or central nervous system disorders (congenital syndromes or those associated with aging) or certain medications. Dysfunction within the ANS flows on a continuum, with many headache patients at the benign end of this scale and patients with Riley-Day syndrome at the severe end. Here is a description of a few common conditions associated with dysautonomia:
Neurocardiogenic Syncope (NCS) is caused by a drop in blood pressure, quickly followed heart rate instability, and results in poor perfusion, then temporary loss of consciousness. Triggers for NCS are anxiety, heat, prolonged standing, or straining. Symptoms prior to syncope include lightheadedness and dizziness, vertigo, nausea, paleness and clamminess, blurred vision, and even seizure-like movements. It is the most common form of dysautonomia.
Postural Orthostatic Tachycardia Syndrome (POTS) reflects changes in the hear5t rate both with movement (sitting to standing) and at rest. Symptoms include tachycardia,l ightheadedness and dizziness, syncope, headaches, fatigue, shortness of breath, and feeling shaky. POTS symptoms can trigger migraine and can also worsen other types of headache.
Inappropriate Sinus Tachycardia (IST) is described as unexpected tachycardia (over 100BPM), with minimal physical activity or at rest. Symptoms include palpitations, weakness, chest pain, shortness of breath, fatigue, dizziness or near-syncope. This diagnosis is made after ruling out other serious causes for tachycardia. It can often cause a diminished quality of life and patients can be symptomatic even with heart rate regulation.
In general, there are many symptoms associated with dysautonomia and each person has their own particular symptoms. Sometimes the symptoms are merely bothersome and puzzling. But sometimes the symptoms are significant and greatly affect the person’s life, can even cause disability. These patients should be evaluated by cardiology to rule out serious conditions and for reassurance. The impact of dysautonomia often depends on the severity of the symptoms as well as the resilience and ability of the patient to tolerate them.
Headache patients usually have a mild version of these autonomic symptoms, but are often concerned that they are signs of a serious issue. Knowledge about these benign, idiopathic symptoms and reassurance can go a long way in preventing unnecessary and unwarranted medical diagnostics and procedures.
Patient education: The most common symptoms adolescent patients complain about are sweaty hands and feet, lightheadedness/orthostatic hypotension/syncope, constipation, and fatigue.There are also many practical ways to deal with the symptoms and difficulties associated with mild dysautonomia.
- Ensuring good hydration, using electrolyte-rich fluids and salty snacks strategically, can help with the orthostatic hypotension. Also helpful are getting up slowly, holding onto desks, using the hand rail when climbing up and down stairs. They need more than the usual baseline 1oz/kg of body weight.
- Hydration is also important for dealing with constipation, in addition to added dietary fiber and medications if needed.
- Monitoring their diet for offending foods, eating small frequent meals, helps with gastric distress and GERD.
- Activity pacing can assist in increasing exercise tolerance; physical therapy may be needed when teens are really deconditioned. The goal is to improve vascular tone with exercise, and reduce symptoms.
- Not much helps with the sweaty axilla, hands and feet, though sometimes a dermatologist can offer topical treatment, such as anticholinergic wipes or even Botox.
- Small fiber neuralgia, is a painful tingling, numbness or sensitivity anywhere in the body, often the hands and/or feet. Strategies to manage these symptoms include exercise, PT, and desensitization, which can help prevent debilitating chronic pain conditions, such as chronic regional pain syndrome.
Describing the symptoms they might experience as a result of instability or over-stimulation of their nervous system is a great source of reassurance to patients and their parents. A good way to talk about mild ANS dysfunction is to say that their autonomic nervous system is being overly stimulated and excited. One way to decrease symptoms is to decrease stimulation to the ANS. This can be done by doing things that trigger the relaxation response, such as yoga, meditation, mindfulness activities, even petting their beloved dog, cat or horse. The effects are not immediate, and improvement is generally noticed over time. It is not a quick fix. But over time, mild ANS dysfunction can be improved in this way.