Positive affect and functional somatic symptoms in young adults

Background Functional Somatic Symptoms (FSS) are symptoms for which an underlying pathology cannot be found. High negative affect (NA) has been linked to the etiology of FSS, but little is known about the role of Positive Affect (PA). Objective: The aim of this study was to test if PA is related to current and future lower levels of FSS. We also examined the interactions between PA and NA, and PA and sex on FSS. Method: Data from the Dutch Tracking Adolescents' Individual Lives Survey (TRAILS) cohort were used (N = 1247 cases, 60% females, mean age T5 = 22.2, T6 = 25.6). PA was measured with the PANAS schedule and FSS with the Adult Self Report questionnaire (ASR). A Principal Component Analysis (PCA) was performed on the physical complaints subscale of the ASR. Regression analyses with bootstrapping were performed to assess the associations and interactions. Results: PA had a significant negative association with current FSS when adjusted for NA, age, sex and socioeconomic status (B = 0.004; BCa 95% CI = [ -0.006; -0.002]), but the association was not significant longitudinally. No interactions were found. In secondary analysis, PA was significantly related to the component "General Physical Symptoms" (B = -0.019; BCa 95% CI = [ -0.0028; -0.011]) but not to the component "Gastrointestinal Symptoms" (B = -0.008; BCa 95% CI = [ -0.016;0.001]) in the cross-sectional analysis. Conclusion: In conclusion, high PA was significantly related to current lower levels of FSS, but the effect was small. Further research on individual variations in affect is needed to obtain more insight in their contribution to FSS.