Cort Johnson writes about research into Functionally Somatic Syndromes on June 1, 2015 in his blog Health Rising:

The study urges the need for more research on FSS, a relatively neglected research area. Especially studies on a better understanding of the etiology and treatment of these disorders are needed.

The term functionally somatic syndrome does not have a great history. A 1999 Annals of Internal Medicine article stated that one of the factors perpetuating FSS’s like ME/CFS, GWS and FM is “the belief that one has a serious disease”.  Times have changed, though. The 2015 study cited below is a “functional somatic syndrome” study that aimed to prove that FSSs are, in fact, serious disorders.

Compared to the “well-defined medical diseases” the FS’s are mysteries in the medical world.

It simply describes FSSs such as chronic fatigue syndrome, fibromyalgia and irritable bowel syndrome as being disorders without “sufficient explanatory pathology”. That, of course, suggests that every FSS is simply a disorder whose underlying pathophysiology is currently unknown. In other words the FSS label is simply a temporary holding pen for difficult to understand (and as we’ll see, often underfunded) diseases.

That inability to define a clear, core pathophysiology has left the door open, though, for “FSSs” to be taken less seriously. Studies suggest, though, that the health care needs and work-related absences associated with them result in high economic losses ($7-10,000/year). Early retirement is not uncommon.  Some studies suggest quality of life and functionality might actually be lower in them than in other chronic illnesses.

This study asked if the lowly FSSs might be as functionally impairing as the some of the big diseases in the well-defined medical disease (MD) category.

The Study:

Functional limitations in functional somatic syndromes and well-defined medical diseases. Results from the general population cohort LifeLines, by Monica L. Joustra a , Karin A.M. Janssens a, Ute Bültmann b , Judith G.M. Rosmalen. Journal of Psychosomatic Research May 16 (2015)

This Dutch study took advantage of a large ongoing cohort study. The study consisted of sending  questionnaires to the 90,000 people in the study, (mostly healthy controls) asking about their medical history, functionality and work experiences

They used the 36 question Rand 36 form to assess quality of life (QOL) and provide a physical and mental component summary.  The physical health component (PHC) combine physical function (10 items),  limitations due to physical problems (4 items), bodily pain (2 items)  and general health (5 items) scores. The mental health component (MHC) combined vitality (4 items), social functioning (2 items), limitations due to emotional problems (3 items) and emotional well-being (5 items) scores. A work participation questionnaire assessed their ability to work.

The study then compared the responses of the healthy controls with people with one or more of three FSS disorders (irritable bowel syndrome, fibromyalgia syndrome, chronic fatigue syndrome) and people who had one of four MD’s (Crohn’s disease and ulcerative colitis, multiple sclerosis and rheumatoid arthritis).

Let’s see how the underfunded, mostly ignored, FSS’s did compared to some of the big boys in the medical world.

Results:
This population-based study revealed that the functional limitations in FSS patients are common and as severe as those in patients with MD, despite the absence of underlying organic pathology. Authors

All told people with FSS’s had significantly lower total quality of life scores than people with well-defined medical disorders (MD’s).  When looked at more closely, the physical components (physical functioning, limitations due to physical health, pain) were not significantly different in the two types of disorders.  People with FSS’s tended to have lower mental health component (MHC) scores; that is, they had significantly lower scores in the  vitality, ability to function socially, reductions in functioning due to emotional issues and emotional well-being scores than did the people with MD’s.

Unfortunately, the study did not break down which of these issues were most prominent, but the authors suggested that increased difficulty dealing with symptoms, stigmatization and lack of treatment options were probably important factors driving the lower MHC scores in the “functional somatic syndrome” group.  (I’ll bet cognitive issues are probably more important in the FSS group as well.)

Similar rates of work participation and early retirement between the FSS’s and MD’s cemented how significant an impact FSS’s can have on work lives.

Conclusion:
Functional limitations in FSS patients are common, and as severe as those in patients with MD when looking at QoL and work participation, emphasizing that FSS are serious health conditions. The Authors

All told, the study suggested that having an FSS such as ME/CFS, FM and IBS, is as, if not more impactful, from a functional standpoint, as having a “well-defined medical condition” such as rheumatoid arthritis, multiple sclerosis and inflammatory bowel disease.

ME/CFS and Fibromyalgia As Functionally Impairing As Major Diseases in Medical World By Cort Johnson on June 1, 2015