Two age peaks in the incidence of chronic fatigue syndrome/myalgic encephalomyelitis: a population-based registry study from Norway 2008-2012

Abstract

BackgroundThe aim of the current study was to estimate sex- and age-specific incidence rates of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) using population-based registry data. CFS/ME is a debilitating condition with large impact on patients and their families. The etiology is unknown, and the distribution of the disease in the general population has not been well described.MethodsCases of CFS/ME were identified in the Norwegian Patient Register (NPR) for the years 2008 to 2012. The NPR is nationwide and contains diagnoses assigned by specialist health care services (hospitals and outpatient clinics). We estimated sex- and age-specific incidence rates by dividing the number of new cases of CFS/ME in each category by the number of person years at risk. Incidence rate ratios were estimated by Poisson regression with sex, age categories, and year of diagnosis as covariates.ResultsA total of 5,809 patients were registered with CFS/ME during 2008 to 2012. The overall incidence rate was 25.8 per 100,000 person years (95% confidence interval (CI): 25.2 to 26.5). The female to male incidence rate ratio of CFS/ME was 3.2 (95% CI: 3.0 to 3.4). The incidence rate varied strongly with age for both sexes, with a first peak in the age group 10 to 19 years and a second peak in the age group 30 to 39 years.ConclusionsEarly etiological clues can sometimes be gained from examination of disease patterns. The strong female preponderance and the two age peaks suggest that sex- and age-specific factors may modulate the risk of CFS/ME.

Chronic fatigue syndrome – an update

“…5 A recent Norwegian study showed 2 age peaks in the incidence of CFS: 10-19 years old and 30-39 years old. 26 They found an incidence of 25.8 per 100,000 person years (95% confidence interval (CI): 25.2 to 26.5), with a female to male incidence rate ratio of 3.2 (95% CI: 3.0 to 3.4).…”

Chronic Fatigue Syndrome at Age 16 Years

“…This assumption was based on our earlier study of family adversity as a risk factor for chronic disabling fatigue in children at age 13 years 8 and on the gender-related difference in CFS prevalence in adults. 21 Psychological problems, life difficulties, and school attendance (all measured at age 16 years) were considered to be potential risk factors for, or consequences of, CFS at age 16 years. 22,23 …”

Chronic fatigue syndrome: Features of a population of patients from northern Italy

“…20 The results confirmed the data of the literature with a female:male ratio of 3:1. 21 The Italian National Agency for Regional Health Services (AGENAS) conducted a survey on the prevalence of CFS, using the ICD (International Classification of disease, ninth revision) codes of hospital discharge records between 2001 and 2010. 22 The results led to the conclusion that CFS is not very widespread in Italy with a prevalence in the range of 0.1-0.2%.…”