You might have qualified for this study if you met the following criteria:
- Male
- Between the ages of 18-65
Met the following criteria for fatigue, post-exertional malaise and/or fatigue, sleep dysfunction, and pain; had two or more neurological/cognitive manifestations and one or more symptoms from two of the categories of autonomic, neuroendocrine, and immune manifestations; and adhered to item 7:
- Fatigue: The patient must have had a significant degree of new onset, unexplained, persistent, or recurrent physical and mental fatigue that substantially reduced activity level.
- Post-Exertional Malaise and/or Fatigue: There was an inappropriate loss of physical and mental stamina, rapid muscular and cognitive fatigability, post-exertional malaise and/or fatigue and/or pain, and a tendency for other associated symptoms within the patient’s cluster of symptoms to worsen. There was a pathologically slow recovery period—usually 24 hours or longer.
- Sleep Dysfunction: There was unrefreshed sleep or sleep quantity or rhythm disturbances such as reversed or chaotic diurnal sleep rhythms.
- Pain: There was a significant degree of myalgia. Pain could be experienced in the muscles and/or joints and was often widespread and migratory in nature. Often there were significant headaches of new type, pattern, or severity.
- Neurological/Cognitive Manifestations: Two or more of the following difficulties should have been present: confusion, impairment of concentration and short-term memory consolidation, disorientation, difficulty with information processing, categorizing and word retrieval, and perceptual and sensory disturbances—e.g., spatial instability and disorientation and inability to focus vision. Ataxia, muscle weakness, and fasciculations were common. There may have been overload phenomena: cognitive, sensory—e.g., photophobia and hypersensitivity to noise—and/or emotional overload, which might have led to “crash” periods and/or anxiety.
- At Least One Symptom from Two of the Following Categories:
- Autonomic Manifestations: Orthostatic intolerance - neurally mediated hypotension (NMH), postural orthostatic tachycardia syndrome (POTS), delayed postural hypotension; light-headedness; extreme pallor; nausea and irritable bowel syndrome; urinary frequency and bladder dysfunction; palpitations with or without cardiac arrhythmias; exertional dyspnea.
- Neuroendocrine Manifestations: Loss of thermostatic stability—subnormal body temperature and marked diurnal fluctuation, sweating episodes, recurrent feelings of feverishness and cold extremities; intolerance of extremes of heat and cold; marked weight change—anorexia or abnormal appetite; loss of adaptability and worsening of symptoms with stress.
- Immune Manifestations: Tender lymph nodes, recurrent sore throat, recurrent flu-like symptoms, general malaise, new sensitivities to food, medications, and/or chemicals.
- The illness persisted for at least six months: It usually had a distinct onset, although it might have been gradual. Preliminary diagnosis might have been possible earlier. Three months was considered appropriate for children.
To be included: The symptoms must have begun or have been significantly altered after the onset of this illness. It was unlikely that a patient would suffer from all symptoms in criteria 5 & 6. The disturbances tended to form symptom clusters that might have fluctuated and changed over time. Children often had numerous prominent symptoms, but their order of severity tended to vary from day to day. There was a small number of patients who had no pain or sleep dysfunction, but no other diagnosis fit except ME/CFS. A diagnosis of ME/CFS could be entertained when this group had an infectious illness-type onset. Some patients had been unhealthy for other reasons prior to the onset of ME/CFS and lacked detectable triggers at onset or had a more gradual or insidious onset.
Exclusions: Excluded active disease processes that explained most of the major symptoms of fatigue, sleep disturbance, pain, and cognitive dysfunction. It was essential to exclude certain diseases, which would have been tragic to miss: Addison’s disease, Cushing’s syndrome, hypothyroidism, hyperthyroidism, iron deficiency, other treatable forms of anemia, iron overload syndrome, diabetes mellitus, and cancer. It was also essential to exclude treatable sleep disorders such as upper airway resistance syndrome and obstructive or central sleep apnea; rheumatological disorders such as rheumatoid arthritis, lupus, polymyositis, and polymyalgia rheumatica; immune disorders such as AIDS; neurological disorders such as multiple sclerosis (MS), Parkinsonism, myasthenia gravis, and B12 deficiency; infectious diseases such as tuberculosis, chronic hepatitis, Lyme disease, etc.; primary psychiatric disorders and substance abuse. Exclusion of other diagnoses, which could not be reasonably excluded by the patient’s history and physical examination, was achieved by laboratory testing and imaging. If a potentially confounding medical condition was under control, then the diagnosis of ME/CFS could be entertained if patients met the criteria otherwise.
Co-morbid Entities: Fibromyalgia Syndrome (FMS), Myofascial Pain Syndrome (MPS), Temporomandibular Joint Syndrome (TMJ), Irritable Bowel Syndrome (IBS), Interstitial Cystitis, Irritable Bladder Syndrome, Raynaud’s Phenomenon, Prolapsed Mitral Valve, Depression, Migraine, Allergies, Multiple Chemical Sensitivities (MCS), Hashimoto’s thyroiditis, Sicca Syndrome, etc. Such co-morbid entities might have occurred in the setting of ME/CFS. Others such as IBS might have preceded the development of ME/CFS by many years but then became associated with it. The same held true for migraines and depression. Their association was thus looser than between the symptoms within the syndrome. ME/CFS and FMS often closely connected and should be considered to be “overlap syndromes.”
Idiopathic Chronic Fatigue: If the patient had unexplained prolonged fatigue (6 months or more) but had insufficient symptoms to meet the criteria for ME/CFS, it should have been classified as idiopathic chronic fatigue.
