Supplementary Material for: Study of rates and factors associated to psychosomatic syndromes assessed using the Diagnostic Criteria for Psychosomatic Research across different clinical settings

Introduction: Diagnostic Criteria for Psychosomatic Research (DCPR) serve as an instrument for identifying and classifying specific psychosomatic syndromes that are not adequately encompassed in standard nosography. The present study aimed at measuring the prevalence of DCPR syndromes in different clinical settings and exploring factors associated to such diagnoses.
Methods: A cross-sectional and nationwide study recruited 6,647 patients in different clinical settings: 306 were diagnosed with fibromyalgia (FM), 333 with irritable bowel syndrome (IBS), 1,109 with migraine, 2,550 with coronary heart disease (CHD), and 2,349 with type 2 diabetes (T2D). Participants underwent DCPR diagnostic interview and were assessed for depression (Patient Health Questionnaire-9), anxiety (Generalized Anxiety Disorder 7-Item Scale), and subjective well-being (World Health Organization-5 Well-Being Index). The PsychoSocial Index was used to evaluate global well-being, stress, and abnormal illness behavior. The prevalence of DCPR diagnoses was calculated, and factors associated to such diagnoses were analyzed by logistic regression.
Results: Alexithymia (64.47%), irritable mood (20.55%), and demoralization (15.60%) were the most prevalent psychosomatic syndromes, with demoralization being most common in FM (49.02%). The factors associated to DCPR diagnoses encompassed high anxiety or abnormal illness behavior, and poor well-being. Notably, stress was found to be associated specifically to FM and T2D, with OR of 1.24 (95% CI: 1.06-1.46) and 1.26 (95% CI: 1.18-1.36), respectively.
Conclusion: DCPR is a clinically helpful complementary assessment tool in need of being widely implemented in clinical settings in order to have a comprehensive picture of the patients.