HEAT INTOLERANCE  & LYME DISEASE
 
 Individuals with chronic Lyme Disease may experience heat intolerance related to an especially hot day, sauna therapy (far infrared, ozone, or conventional), hot tub/whirlpool use, or even a hot shower.  These symptoms may be aggravated by a standing position, dehydration, and certain medications.   The severity of these symptoms can range from mild to life-threatening
 
Most people understand that longstanding Lyme Disease can damage the nervous system.  This damage may affect the central nervous system, the brain and spinal cord.   In addition, the peripheral nervous system, the individual nerves outside of the spinal cord that control the muscles of our arms and legs, and the nerves to our organ systems may be damaged as well.   The peripheral nervous system is divided into the somatic nerves and the autonomic nerves.   Somatic nerves, or nerves to our muscles and skin, affect feeling and movement.   Autonomic nerves control our organs to include the heart, blood vessels, bowel function, bladder function and other internal organs.
 
Lyme Disease may damage the central nervous system in many ways.   One area that can be impacted is the hypothalamus and pituitary gland which are located in the center of the brain.   The pituary gland is often referred to as the "master gland" in that it controls many other endocrine glands including the thryoid, adrenal glands, ovaries, and testicules.   An endocrine gland, by definition, is a gland that secretes hormones into the blood which then contols other parts of the body.   When Lyme Disease damages the pituitary gland, it can have an impact on all of these other glands and cause deficiency symptoms.   On can become hypothyroid (low thyroid function) or have decreased adrenal hormone output as a result of damage in the brain.   This type of problem is referred to as a secondary endocrinopathy or an endocrine problem caused by some other area of the body other than a particular gland itself.   For instance, if the pituitary is damaged and does not secrete enough of the hormone that's needed to simulate the thryoid (TSH-thryoid stimulating hormone) one would label this problem as a secondary endocrinopathy.
 
In addition to secondary endocrinopathies, Lyme Disease may directly damage endocrine glands.   The pancreas may be damaged directly resulting in diabetes, the adrenal glands may be damaged directly resulting in adrenal insufficiency, or the thryoid might be damaged resulting in low thyroid function or hypothyroidism.  
 
Primary and secondary endocrine disorders are reasonably well understood.   What isn't understood is that Lyme Disease can cause BOTH primary and secondary endocrine disorders at the same time.   Unravelling this situation is near impossible.  There is nothing written, to my knowledge, in any text book about a medical model for this type of complex situation and few doctors understand the concept.    Lyme Disease is capable of damaging just about any part of the body and that's why this complex situation may exist.   In either type of endocrinopathy, replacement therapy is usually prescribed.
 
Whether primary or secondary, it is not uncommon for Lyme patients to have some degree of adrenal insufficiency.    Moreover, standard testing generally isn't adequate because the usual variation of adrenal hormone, cortisol, does not follow the usual patterns.   In normal people, cortisol levels are highest in the morning and lowest as night.   In Lyme Disease this pattern is often interrupted and reversed.   Should someone have adrenal insufficiency, their bodies do not produce enough adrenal hormones.   These hormones include testosterone, cortisol, norepinenephrine and epinephrine.   People often feel weak, have low blood pressure, feel depressed and may not be able to respond to stress.   When severe, adrenal failure can result which is life threatening.
 
Epinephrine and norepinephrine are the major vasoactive substances produced...or the chemicals that maintain or increase blood pressure.   If a person is subjected to high temperatures, this results in vasodilation of the skin...or a condition were the blood vessels enlarge in the skin and therefore lowers blood pressure.   In order to maintain normal blood pressure, the body has regulatory mechanisms, receptors in the aorta and carotid arteries that can detect low blood pressure, so that more epinephrine and norepinephrine are released.   These substances will then increase and maintain a normal blood pressure.    In patients with Lyme Disease, these regulatory mechanisms may be impaired and thus, the individual may not be able to maintain proper blood pressure.   With low blood pressure, the individual will often note a rapid weak heart beat, weakness, dizziness, and if severe enough, shock.   Shock being a state where there is insufficient blood pressure to maintain adequate blood flow to vital organs.   Shock may be preceded by heat exhaustion, a condition where a person may have an elevated temperature, low blood pressure, dehydration and mental confusion.
 
Peripheral neuropathy is not an uncommon problem in Lyme Disease.    People with peripheral neuropathy have some degree of weakness and numbness of their lower extremities or hands.   When present and if of a longstanding nature, it may also coexist with automonic dysfunction as the autonomic nervous system is part  of the peripheral nervous system.     The autonomic nervous system has receptors located in the aorta (largest blood vessel in the body) and the carotid arteries (the arteries supplying the brain).   If these sensors are damaged or impaired as they may be in Lyme Disease, then the body cannot react normally to a low blood pressure event.   Add to that possible adrenal impairment, and maintaining proper blood pressure becomes even more difficult.
 
It is a known fact that adrenal insufficiency is a "relative" contraindication to using a sauna.   A "relative" contraindication means that if a sauna is used, it should only be used with the understanding that danger exists and that a physician should  be consulted before using this therapy.   Similiarly, people that have known Lyme Disease may be at increased risk of dehydration and heat exhaustion as their bodies regulatory mechanisms do not always function as well as others.
 
Understanding  how the body works and how Lyme Disease impacts so many different organ systems can aid us in taking necessary health safety precautions.   In particular, people with Lyme Disease may need to pay particular attention to heat exposure in all of it's forms be it a hot day, sauna therapy, jogging, or the use of a hot tub.    Should one feel that they may be particularly sensitive to heat exposure, further evaluation by a competent physician knowledgable of Lyme Disease would be most helpful.
 
To Your Good Health,
 
James W.  Cilecek MD