Risk factors for severe ME/CFS
ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome) is a serious illness affecting several hundred thousand British people. Some 25% of people with ME/CFS may be severely ill (housebound or bedbound), sometimes for decades. This observational, questionnaire-based study was designed to identify risk factors for severe disease. Exposure to potential risk factors, including familial risks, personality, and early management of the illness, was compared in 124 people with severe disease and 619 mildly ill controls. Severity was determined by self-report and the Barthel (activities of daily living) Index. Premorbid personality was assessed using the Neuroticism and Conscientiousness domains of the IPIP scale. Analysis was by tests of association and logistic regression. Early management of the illness appeared the most important determinant of severity. Having a mother with ME/CFS was also important. Smoking and personality were not risk factors, neurotic traits being more frequent among the less severely ill. Conscientiousness overall was not related to severity.