The upper airway resistance syndrome (UARS) is often misdiagnosed as FMS or CFS. It has a similar pathophysiology as obstructive sleep apnea. UARS is a sleep disorder characterized by airway resistance to breathing during sleep. It is often undiagnosed. Patients with UARS often have hypotension, cognitive impairment, frequent nocturnal awakenings, non-restorative sleep, constant fatigue or excessive daytime somnolence, anxiety, depression, and chronic muscle pain may be present. The diagnosis of UARS is made by a polysomnography. Nocturnal positive airway pressure (CPAP), the same as that for sleep apnea obstructive treatment, helps provide almost definitive solution to this so-called FMS/CFS. Sedatives and narcotics products often prescribed for FMS/CFS will be contraindicated at risk of aggravating the UARS.
The restless legs syndrome (RLS), also called nocturnal leg restlessness, is relatively common in FMS. It is a neurological disorder that causes an irresistible urge to move the legs to stop uncomfortable or odd sensations. It most commonly affects the legs, but can affect the arms, torso and head. RLS sensations range from pain or an itching in the muscles to tingling, tickling, burning, crawling, creeping, numbness, or electrical feelings, whose intensity varies greatly from one person to another. These unpleasant sensations occur particularly during periods of relaxation or inactivity. Therefore, it can be very difficult to just rest, or sit to attend a meeting or travel by plane, for example. Because symptoms tend to worsen in the evening and at night, falling asleep is more difficult. Chronic insomnia that can result causes fatigue and sleepiness during the day, altering dramatically the quality of life. Some people even tell you the feeling having marched all night.