Incidence of myalgic encephalomyelitis/chronic fatigue syndrome in a large prospective cohort of U.S. nurses
Palacios et al
ABSTRACT
Background: The incidence of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), the rates of both under-diagnosis and over-diagnosis, and the nature of the onset of the condition have not been assessed in large studies of health professionals.
Purpose: To determine the cumulative incidence of ME/CFS in a large population of health professionals, to examine the nature of the onset of the illness, and to estimate the frequency of both over-diagnosis and under-diagnosis of ME/CFS.
Methods: We sent an email questionnaire to participants in the Nurses’ Health Study II (NHS II), a large prospective cohort of female nurses. Forty-two thousand three hundred and ninety-four women completed the questionnaire, which included the 1994 Centers for Disease Control and Prevention (CDC) criteria for ME/CFS.
Results: One-hundred and two women (240 per 100,000 surveyed) developed an illness that met criteria for ME/CFS between 1989 and 2009. The onset of ME/CFS was gradual in 40.6%, sudden (following flu-like illness or other precipitating events) in 18.8%, followed emotional or physical trauma in 32.3%, and was uncertain in the rest. Under-diagnosis was common: only 15 (15%) of the women who met criteria for ME/CFS reported having been diagnosed. Over-diagnosis also was common: four times as many subjects had been diagnosed with ME/CFS by community doctors as actually met criteria. The distribution of symptoms was not different in comparing cases with a sudden onset to those with a gradual onset.
Conclusions: In this large cohort of female nurses, we found a low cumulative incidence of ME/CFS. Over-diagnosis and under-diagnosis were high, even in this medically sophisticated population.
Also
https://www.tandfonline.com/doi/abs/10.1080/21641846.2017.1323576
Systematic review and meta-analysis of the prevalence of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME)
Additionally, the prevalence in specific populations, such as nurses and Gulf War veterans, seems to be slightly higher (1.62%) than that in the general population (1.45%) (Table 2); however, as others have argued, this difference could result from methodological inconsistencies [18].
In this (narrow) matter Wessely may be blameless
:
In
The epidemiology of chronic fatigue syndrome referencing Gunn
Epidemiology of Chronic Fatigue Syndrome: The Centers for Disease Control Study Wessely writes
:
"There is general agreement that CFS as observed in specialist centres has certain characteristics. For example, study after study reports that sufferers are more likely to be females, come from higher socio-economic groups, and indeed show a particular overrepresentation of certain professions, such as teachers or nursing. Of the 3,000 individuals who phone the Center for Disease Control CFS Information Line every month a quarter are medical or para-medical (Gunn, 1993). The occasional attempt is made to explain this finding in terms of viral exposure (both in childhood and at work), and overwork. Such explanations (reminiscent of those advanced to account for the same apparent excess of middle class professionals in the ranks of neurasthenia sufferers (Sicherman, 1977; Wessely, 1994)) , are unconvincing, with the possible exception of EBV virus, since lower socio-economic status is associated with an increased risk of primary EBV infection in childhood (Sumaya & Ench, 1985). Other explanations include access to health care, and differential labelling by both sufferer and doctor. In contrast to the pattern observed in specialist samples of CFS, there is no evidence for any excess of higher socio-economic status for fatigue, chronic fatigue or chronic fatigue syndrome observed in the community
or primary care (Cox et al, 1987; Wessely et al, in press; Fukuda et al, 1997; Shefer et al, 1997). Likewise, strong physical attributions and intense disease conviction are the norm. In contrast, ethnic minorities are rarely encountered."
