Prevalence, incidence, and classification of chronic fatigue syndrome in Olmsted County, Minnesota, as estimated using the Rochester Epidemiology Project

Abstract:

OBJECTIVE: To estimate the prevalence and incidence of chronic fatigue syndrome in Olmsted County, Minnesota, using the 1994 case definition and describe exclusionary and comorbid conditions observed in patients who presented for evaluation of long-standing fatigue.

PATIENTS AND METHODS: We conducted a retrospective medical record review of potential cases of chronic fatigue syndrome identified from January 1, 1998, through December 31, 2002, using the Rochester Epidemiology Project, a population-based database. Patients were classified as having chronic fatigue syndrome if the medical record review documented fatigue of 6 months’ duration, at least 4 of 8 chronic fatigue syndrome-defining symptoms, and symptoms that interfered with daily work or activities. Patients not meeting all of the criteria were classified as having insufficient/idiopathic fatigue.

RESULTS: We identified 686 potential patients with chronic fatigue, 2 of whom declined consent for medical record review. Of the remaining 684 patients, 151 (22%) met criteria for chronic fatigue syndrome or insufficient/idiopathic fatigue. The overall prevalence and incidence of chronic fatigue syndrome and insufficient/idiopathic fatigue were 71.34 per 100,000 persons and 13.16 per 100,000 person-years vs 73.70 per 100,000 persons and 13.58 per 100,000 person-years, respectively. The potential cases included 482 patients (70%) who had an exclusionary condition, and almost half the patients who met either criterion had at least one nonexclusionary comorbid condition.

CONCLUSION: The incidence and prevalence of chronic fatigue syndrome and insufficient/idiopathic fatigue are relatively low in Olmsted County. Careful clinical evaluation to identify whether fatigue could be attributed to exclusionary or comorbid conditions rather than chronic fatigue syndrome itself will ensure appropriate assessment for patients without chronic fatigue syndrome.

Copyright © 2012 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

 

Source: Vincent A, Brimmer DJ, Whipple MO, Jones JF, Boneva R, Lahr BD, Maloney E, St Sauver JL, Reeves WC. Prevalence, incidence, and classification of chronic fatigue syndrome in Olmsted County, Minnesota, as estimated using the Rochester Epidemiology Project. Mayo Clin Proc. 2012 Dec;87(12):1145-52. doi: 10.1016/j.mayocp.2012.08.015. Epub 2012 Nov 8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3518652/ (Full article)

 

Chronic fatigue syndrome in Minnesota

Abstract:

Chronic fatigue syndrome (CFS), an illness characterized by debilitating fatigue and a number of associated symptoms, was identified in 135 patients using the case definition provided in 1988. The demographic features of these patients, 97% of whom resided in Minnesota, were similar to those reported elsewhere.

About three-fourths of the cases occurred between 1984 and 1989, and in 123 (91.1%), the illness began with what appeared to be an acute infection. Patients had been ill for an average of 4.3 years before enrollment in the study.

Fatigue was their most troublesome symptom, although a majority of the patients rated most of the general symptoms and neuropsychological complaints associated with CFS as moderate or severe. Follow-up data obtained on 62 patients one year after initial evaluation revealed that none had completely recovered. However, about 40% reported some improvement in each of the CFS symptoms.

 

Source: Peterson PK, Schenck CH, Sherman R. Chronic fatigue syndrome in Minnesota. Minn Med. 1991 May;74(5):21-6. http://www.ncbi.nlm.nih.gov/pubmed/1861659