address all conditions and comorbidities that are present and their possible interrelationships. This chapter briefly describes 12 common conditions that are comorbid with or related to CMI and presents treatments that are known to be effective. The committee believes that symptoms shared between CMI and those treatments may respond to similar approaches in symptom management. Treatments that are recommended in evidence-based clinical practice guidelines or that have been found effective in systematic reviews are highlighted. The chapter concludes with a general therapeutic approach to patients who have the most common diagnostic clusters.
Primary fibromyalgia is a relatively common chronic condition that is thought to be caused by abnormal processing of pain by the central nervous system (Abeles et al., 2007). Using US population estimates from 2005, the estimated prevalence of fibromyalgia in the United States was about 5 million people (Lawrence et al., 2008). It is characterized by chronic widespread pain, fatigue, cognitive symptoms, and sleep disturbance. Anxiety and depression can accompany the syndrome (Wolfe et al., 1990). The diagnostic criteria of the American College of Rheumatology are as follows (Wolfe et al., 2010):
1. Pain over the preceding week identified from a list of 19 areas of the body.
2. Fatigue, waking unrefreshed, and cognitive symptoms (memory disturbance).
3. Symptoms lasting longer than 3 months.
4. Symptoms not explained by any other medical condition.
Other conditions may resemble fibromyalgia closely, including hypothyroidism, polymyalgia rheumatica, rheumatoid arthritis, and systemic lupus erythematosus.
Fibromyalgia and Chronic Multisymptom Illness
Fibromyalgia and CMI share symptoms. The hallmark of fibromyalgia is chronic widespread pain. In CMI, muscle pain and tenderness are very common but are not required for the diagnosis.
Treatments for Fibromyalgia
Many pharmacologic and nonpharmacologic treatments have been demonstrated to be effective for fibromyalgia. Many categories of pharmacologic