P.E.N.E. Post-Exertional Neuroimmune Exhaustion
The information provided at this site is not intended to diagnose or treat any illness and is not to be considered as medical advice.
Below is information from the International Consensus Primer for ME that relates to P.E.N.E.
We feel it is important all people with myalgic encephalomyelitis (ME) read the ME IC Primer, however, this is written for medical professionals. We have asked members to put the information into wording the average person can understand. These are listed after the IC Primer information as well as several videos and articles that might help.
P.E.N.E. per #MEICPrimer
IC Primer, Page 2
Post-Exertional Neuroimmune Exhaustion (PENE pen׳-e)
“Normal fatigue is proportional to the intensity and duration of activity, followed by a quick restoration of energy. PENE is characterized by a pathological low threshold of physical and mental fatigability, exhaustion, pain, and an abnormal exacerbation of symptoms in response to exertion. It is followed by a prolonged recovery period. Fatigue and pain are part of the body’s global protection response and are indispensable bioalarms that alert patients to modify their activities in order to prevent further damage.
The underlying pathophysiology of PENE involves a profound dysfunction of the regulatory control network within and between the nervous systems. This interacts with the immune and endocrine systems affecting virtually all body systems cellular metabolism and ion transport. The dysfunctional activity/rest control system and loss of homeostasis result in impaired aerobic energy production and an inability to produce sufficient energy on demand. A test-retest cardiopulmonary exercise study revealed a drop of 22% in peak VO2 and 27% in VO2 at AT on the second day evaluation. Both submaximal and self-paced exercise resulted in PENE. These impairments and the loss of invigorating effects distinguish ME from depression.”
IC Primer, Page 7
Post-Exertional Neuroimmune Exhaustion (PENE pen׳-e) Compulsory
“This cardinal feature is a pathological inability to produce sufficient energy on demand with prominent symptoms primarily in the neuroimmune regions. Characteristics are:
Marked, rapid physical and/or cognitive fatigability in response to exertion, which may be minimal such as activities of daily living or simple mental tasks, can be debilitating and cause a relapse.
Post-exertional symptom exacerbation: e.g. acute flu-like symptoms, pain and worsening of other symptoms.
Post-exertional exhaustion may occur immediately after activity or be delayed by hours or days.
Recovery period is prolonged, usually taking 24 hours or longer. A relapse can last days, weeks or longer.
Low threshold of physical and mental fatigability (lack of stamina) results in a substantial reduction in preillness activity level.”
IC Primer, Page 7
Operational Notes (Recovery Time)
“There may be marked fluctuation of symptom severity and hierarchy from day to day or hour to hour. Consider activity, context and interactive effects.
Recovery time: e.g. Regardless of a patient’s recovery time from reading for ½ hour, it will take much longer to recover from grocery shopping for ½ hour and even longer if repeated the next day – if able. Those who rest before an activity or have adjusted their activity level to their limited energy may have shorter recovery periods than those who do not pace their activities adequately.
Impact: e.g. An outstanding athlete could have a 50% reduction in his/her pre-illness activity level and still be more active than a sedentary person.”
IC Primer, Pages 11-12
PENE (2 day CPET)
“A 2 consecutive day comprehensive 8-12 minute cardiopulmonary exercise stress test (measuring heart, lung, and metabolic function) – only ME patients have significantly worse scores the second day & abnormal recovery from exertion.
- Exercise tolerance test with expired gas exchange – (2 consecutive days) – measure cardiovascular, pulmonary & metabolic responses at rest & during exercise: peak oxygen consumption VO2 or VO2 at anaerobic threshold (AT) – decline of 8% or greater on test 2 indicates metabolic dysfunction, □ post-exercise blood analysis – increase in sensory, adrenergic and immune genes – increase in metabolite receptors unique to ME.”
(The 2 day Cardio Pulmonary Exercise Test (CPET) is available at the Workwell Foundation (California) and Ithaca College (New York) and is specifically designed to look for an inability to repeat physical activity for two days in a row.)
What P.E.N.E. means to ME Patients in their own words
“When a person is normal, they can exercise, rest and after a while be back to normal energy. With someone with ME, if they don’t pace their activities and overdo, they use up all of their energy and as a result it takes hours, sometimes days or longer to get back to baseline. Sometimes people will compare it to having a cell phone at 25% and that has to last you for the day. This might be both physical activities or cognitive activity. These can be simple activities, like brushing your teeth, going to the bathroom etc. Taking a shower might take all the energy for the day. This is typically a crash. If patients know when they have reached their limit and stop, they have a much better opportunity to not get worse. The one problem is many patients just don’t have the support in order to rest and pace. They are forced to work, take care of family and children, and find themselves crashing for days. Crashes often happen many hours after the activity is over. Many are not believed by their families and lose family support and must survive on their own, often with limited resources and money. When people push too many times and end up with many crashes often make their conditions so bad that they end up housebound or bedbound. Some even require constant Caregivers in order to survive. People with support and caregivers have the best chance of living a fairly normal life. There are three stages of abilities, Mild meets the criteria for ME but have significantly reduced activity. Moderate means that you are at about 50% of what you did before ME, and the last is severe. These people are mostly housebound and very severe are bedridden and are in constant need of assistance with all their activities.”
“PENE – post-exertional neuroimmune exhaustion.
This hits me about 30 hours after activity. For me a key factor is my immune system clearly gets worse during PENE. I get infections, cold sores, sore throats, etc. I feel much sicker and my stamina gets worse. My cognition gets a lot worse and my sensitivities are a lot worse as well. I also have more difficulty keeping my heart rate (HR) at a safe level. I can gauge that I am in PENE or going into PENE if my morning resting HR is higher than my normal. Other symptoms as I am going into or in PENE is louder tinnitus, loss of peripheral vision, loss of muscle control so I walk like a drunken sailor, drop things, spill drinks, miss my mouth when eating, trouble swallowing, food not going all the way down my throat without conscious effort, etc.”
“Exacerbation of all symptoms. Lower baseline of function. Every ‘action’ became much harder, some usually attainable actions become impossible. Less essential function ceases, for me in a very specific order, speech such as directing a PA, walking in the house, being upright, speaking, sounds, light.
BP drops to 90s/60s (I usually aim to keep it around 150sh/90
Temp drops to 33.8-35°F
HR drops to the 30s.
At worst I become paralysed for a period of hours, can hear but can’t open my eyes or speak, limbs get cold, core temperature heats up, super sensitive to sound and movement. Over a period of hours, I regain the ability to move an arm, by a couple of cms, legs same, head same, then open eyes for seconds, speak 1-3 words in a whisper. Then slow recovery, taking weeks to return to a previous baseline.
PENE was described by my dentist at the hospital who has seen me go into paralysis on a number of occasions as a ‘neurological shutdown’ as the brain limits unnecessary function to conserve energy to sustain core, life dependent functions – it is a protective state. Naviaux research 2016 fits me absolutely.”
“In addition to what is in the Primer, sinus congestion and extreme pain are very much part of PENE for me. They actually start many hours before I am in PENE. I have never had a sinus infection but the inflammation flares there even 2 or 3 days before the crash. I often wonder if it is immune and caused by HHV6A being able to activate more. Only a nasal swab and testing for HHV6A in the sample would prove that hypothesis. I use to think that this sinus reaction was just something weird specific to me. But years ago I read somewhere a doctor with ME reporting the same peculiar symptom of sinus inflammation as a signal that a full PENE event was coming”.
“Severe PENE feels sometimes like dying. Hardly able to move or to breath. With severe sensitivity to sound, light and touch. Increased pain in lymph nodes”
“I understand PENE to be basically synonymous with the general fatigability and low threshold to any activity, even stimuli like light, sound or touch.
Viewed that way, ME is PENE, with the acute symptom exacerbation after any exertion’s being just one observable result.
Personally I regularly experience prolonged bouts of visual snow, increased tinnitus, reduction of depth perception, extreme light sensitivity, warped states of consciousness that feel like nightmares or intoxication of some kind, anxiety & depression, inability to communicate, swelling of throat, inability to eat, swallow & digest, flare-ups of joint pain & burning sensations in feet + legs, sores in nose + ears, broken sleep patterns, weakness, ataxia, exacerbated OI + resting heart rate + POTS…”
“Support is needed to prevent crashes in the first place. I am blessed to have great support. Now that my husband is retired he brings me electrolytes and breakfast almost every morning, does all the driving, shopping, most of the household chores which helps prevent PENE. He also pushes me in a wheelchair for any long outing. There have been times he is traveling. He makes sure I am well supplied and then I limit my activity, pay much closer attention to what I eat and do smaller meals more often and try to rest much more. PENE is very scary when alone. If in PENE he knows the drill: keep me fed and hydrated, quiet, dark; ride it out.
For people who are trying to manage this on their own, we need medical professionals to help patients get the support needed to prevent PENE. Every little thing that makes life easier adds up to huge improvement to quality of life and fewer episodes of PENE. Patients may not be aware how much they are pushing through. They need:
Blue parking placards
Cane chairs so one can sit as much as possible during an outing
Support coming in to clean the home, etc.
Fully understanding the danger of PENE means recognizing that we MUST find ways to avoid it as much as possible”
Articles/Videos about P.E.N.E.
How Do I Know if I Have ME? A good article by How to Get On.
Assisting the M.E. patient in managing relapses and adrenaline surges from Hummingbirds Foundation for M.E. (unsecure)
Classic Pacing for a Better Life with M.E. by Ingebjørg Midsem Dahl (from Norway) is a self-help book which explains pacing and how it can be applied to daily life. Additional information can be had through the Menu button.
“Expanding Physical Capability in ME/CFS” Part 1 (of 2) by Dr. Mark Van Ness. This is the first of a two part 2016 May Awareness presentation for the ME/FM Society of BC.