Prognosis

The physical severity of chronic fatigue syndrome varies. Most commonly, patients with CFS report that they have trouble fulfilling both home and work responsibilities.

CFS sufferers typically work part-time. In extreme cases, patients are severely disabled and even bedridden. Such patients can do virtually nothing, including even light housework.

In a 2003 study, patients with either CFS or fibromyalgia were more likely to suffer losses of jobs, possessions, and support from friends and family than people suffering from other conditions that caused fatigue.

Mental Incapacity

Most patients say that while fatigue is the most incapacitating symptom, those of mental impairment, such as an inability to concentrate or memory loss, are the most distressing. The effects of CFS on mental functioning are complex, however. Some experts believe that the impaired mental functioning is due to depression, which is common in CFS patients.

Some studies indicate that although general intelligence is not impaired, CFS patients test lower in certain mental functions, particularly speed and efficiency in processing complex information, and that 40 - 60% suffer memory impairments. In such studies, this impaired mental function occurs regardless of the presence or absence of depression or other psychiatric disorders. A comparison study of patients with depression, CFS, and multiple sclerosis helped support a physical basis for CFS by finding that problems in mental functioning were consistent among MS and CFS patients, no matter how depressed they were. Problems in mental functioning among depressed patients varied, however, depending on the severity of the depression.

One study found that the mental impairment in CFS patients parallels the degree of their physical impairment, indicating that the disease process itself may exert a neurologic effect. A 2005 study found that people with CFS have to work harder to process information they hear, and they use more extensive regions of the brain, than people without the disease.

Long-Term Outlook in Adults

Because the illness remains elusive and poorly defined, and there are few objective measures for recovery, experts have found it difficult to determine the long-term course of the disease. Many patients are not covered by insurance or have difficulty finding good care, so available statistics may be incorrect. Bearing these factors in mind, some studies have reported that between 58 - 72% of patients who complain of chronic fatigue continue to experience it after a year. In one study, nearly 60% were still fatigued at 2 years. Even if patients get progressively worse, however, the disorder is not fatal.

Sudden or Gradual Onset. Some studies have observed that patients whose symptoms began abruptly following a severe viral illness recovered completely after 6 months to a year, whereas patients whose problems developed slowly and insidiously experienced symptoms for a longer period of time.

Severity of CFS. Many patients with moderate chronic fatigue have reported an increase in energy after a year or two. One small 1999 study observed that even after 4 years few patients with severe CFS had returned to their pre-illness state. It should be noted, however, that in another study, nearly all patients with severe CFS who were treated with a multidisciplinary rehabilitation program improved significantly and the gains were maintained for at least a year afterward.

Signs of Positive Outlook. According to one study, CFS patients who are more likely to experience improvement over time have the following positive signs:

  • Can think clearly most of the time
  • Have no other physical or emotional complaints beyond CFS symptoms
  • Sleep well

Outlook in Children

Although children with symptoms of chronic fatigue have not been as rigorously studied as adults, limited evidence suggests that CFS can be significantly disabling in young people. Studies report that adolescents who meet the criterion for CFS also have greater anxiety, depression, and school absenteeism than their peers. Still, some studies indicate that children have a better prognosis than adults and that most will recover after 1 to 4 years. Several studies have indicated that cognitive-behavioral therapy is an effective treatment for adolescents with CFS.