Two age peaks in the incidence of chronic fatigue syndrome/myalgic encephalomyelitis: a population-based registry study from Norway…, 2014, Bakken+

[SNT Gatchaman]

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

Spoiler: Authors

Bakken, Inger Johanne; Tveito, Kari; Gunnes, Nina; Ghaderi, Sara; Stoltenberg, Camilla; Trogstad, Lill; Håberg, Siri Eldevik; Magnus, Per

BACKGROUND
The 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.

METHODS
Cases 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.

RESULTS
A 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.

CONCLUSIONS
Early 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.

Web | PDF | BMC Medicine | Open Access

 

[SNT Gatchaman]

Older paper (2014) predating S4ME, but relevant for review due to —

Audrey Ryback talked about her work on electronic health care records in Lothian. This is impressive. They appear to have a genuinely population based cohort. The prevalence was up at 0.8% - 7,000 cases out of 900,000 people. In other words everyone with ME/CFS in a defined area. This begins to look like solid population data. (And I suspect GPs in Lothian are relatively good about coding ME/CFS compared to some places.)

The data provide a variety of measures of disease dynamics. Audrey stayed with us Wednesday night and also showed me work she has been doing with Simon on age of incidence profile which are to me pretty mind-blowing. Clues from the old Norwegian study look as if they are replicable. […] To me it looks as if there is a totally novel aspect to ME/CFS disease dynamics worth a very deep look at.

I'm glad you think that. I am biased, but I've been stunned by the findings.

See general discussion thread The two age peaks in onset of ME/CFS.

 

[Hoopoe]

What is Ryback's work showing? The same two age peaks or something more?

What do these two age peaks suggest?

What are the hypotheses on the reason for the peak in adolescence? Brain maturation associated with becoming an adult? Sex hormones?

What other illnesses show two age peaks?