Lipid metabolism and functional somatic disorders in the general population. The DanFunD study, 2024, Jørgensen, Fink et al

Abstract

Objectives
Earlier studies on the association between plasma lipid profiles and functional somatic disorders (FSD) are mainly small case control studies hampered by selection bias and do not consider the great overlap between the various FSDs. The aim of the present study was to investigate the associations between various FSDs and plasma lipid profiles (total cholesterol, HDL cholesterol, non-HDL cholesterol and triglycerides) in a large, unselected population.

Design
A cross-sectional general population-based study

Setting
The Danish Study of Functional Somatic Disorders (DanFunD) conducted in 2011–2015 in 10 municipalities in the western part of greater Copenhagen, Denmark.

Participants
A total of 8,608 men and women aged 18–76 years were included in the analyses. Various delimitations of FSD such as chronic fatigue, chronic widespread pain, irritable bowel, and bodily distress syndrome were measured using validated self-administrated questionnaires. Lipid parameters were measured from fasting plasma samples using colorimetric slide methods with Vitros 4600/5600 Ortho Clinical Diagnostics.

Outcome measures
Logistic regression analyses were used to calculate possible associations between plasma lipids and the various delimitations of FSD. Associations are presented by OR (95% CI) and shown in boxplots.

Results
We found a positive association between bodily distress syndrome and triglycerides and non-HDL cholesterol and a negative association with HDL-cholesterol, but no consistent association with total cholesterol. A similar pattern was observed for persons with chronic fatigue, and to some degree for persons with chronic widespread pain, whereas persons with irritable bowel did not show a clear association with the lipid profiles.

Conclusion
This is the first major study on plasma lipid profiles and FSD indicating an association between some delimitations of FSD and an unfavorable lipid profile. Due to the cross-sectional design, it cannot be determined whether the findings are consequences or determinants of FSD. Further studies–preferable prospective studies—are needed.

Open access, https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0296799

 

They also say this
"Functional Somatic Disorders (FSD) refer to clusters of recurrent disabling bodily symptoms (e.g. chronic fatigue, pain) and are prevalent in all medical settings [1]. FSD cannot be better explained by other somatic or psychiatric condition and varies from mild to severe symptoms that may cause extreme impairment [2]. FSD are associated with poor quality of life, and loss of labor market attachment [3, 4].

The literature comprises a huge variation of various delimitations of FSD, the most used are fibromyalgia (FM) or chronic widespread pain (CWP), chronic fatigue syndrome (CFS) and irritable bowel syndrome (IBS). A well-documented substantial overlap between these syndromes has led to the question whether they are distinct diseases or represent the same underlying condition [5, 6]. Therefore, the diagnostic construct of bodily distress syndrome (BDS) [7, 8] was introduced as a unifying diagnostic approach, a construct which has been verified in the general population [9]. The etiology of FSD is considered multifactorial, but as no clear physiological or biological markers has yet been identified [10], the diagnosis of the various FSD is based on identification of characteristic symptom patterns."

and

"Due to the many delimitations of CFS, IBS, and CWP/FM we avoided the word syndrome and used instead chronic fatigue (CF), chronic widespread pain (CWP), and irritable bowel (IB)."

So they don't want to talk about CFS, but do want their results to apply to CFS, while wanting to label everything as functional, and as BDS, and lumping everything together.