The relationship between alexithymia and circulating cytokine levels in subjects undergoing upper endoscopy.
OBJECTIVE
Despite emerging evidence suggesting a link between alexithymia and immune function, previous studies yielded contrasting results. The proposed link between alexithymia and immune function remains controversial as does the role, in this relationship, of anxiety, depression and subjective stress. The aim of the study is to investigate the possible association between alexithymia and circulating levels of cytokines in subjects awaiting an upper endoscopy, a stressful procedure, controlling for anxiety levels, depression and subjective stress.


METHODS
Participants were recruited from among consecutive patients referred for routine diagnostic upper endoscopy. All participants completed the Toronto Alexithymia Scale (TAS-20), the Hospital Anxiety and Depression Scale, and the Stress-related Vulnerability Scale. Serum levels of IL-1β, IL-4, IL-6, IL-10, TNF-α and IFN-γ were measured by ELISA.


RESULTS
Of the 90 subjects initially approached, 68 completed the study. The TAS-20 identified 22 alexithymic and 36 non-alexithymic patients. ELISA detected significantly lower IL-4 and IL-6 concentrations in alexithymic than in non-alexithymic patients. According to multiple linear regression analysis, alexithymia predicted low IL-4 and IL-6 levels in the sample overall, independently of stress, anxiety, depression and other possible confounders. No between-group differences were found in serum levels of IFN-γ, IL-1β, and TNF-α.


CONCLUSIONS
These findings argue against an isolated shift towards pro-inflammatory or anti-inflammatory mediators and suggest that circulating cytokine profiles differ in alexithymic and non-alexithymic subjects.
Mandarelli
Gabriele
G
Department of Psychiatric Sciences and Psychological Medicine, 'Sapienza' University of Rome, Rome, Italy. gabriele.mandarelli@uniroma1.it
Tarsitani
Lorenzo
L
Ippoliti
Flora
F
Covotta
Francesco
F
Zerella
Maria Paola
MP
Mirigliani
Alessia
A
Biondi
Massimo
M
D000328:Adult; D000342:Affective Symptoms / Q000097:blood / Q000276:immunology* / Q000523:psychology; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000097:blood*; D016145:Endoscopy, Digestive System / Q000009:adverse effects / Q000523:psychology; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000097:blood; D016753:Interleukin-10 / Q000097:blood; D053583:Interleukin-1beta / Q000097:blood; D015847:Interleukin-4 / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012044:Regression Analysis; D013315:Stress, Psychological / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D016207:Cytokines; D053583:Interleukin-1beta; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D015847:Interleukin-4; D007371:Interferon-gamma