Illuminating the clinical significance of alexithymia subtypes: A cluster analysis of alexithymic traits and psychiatric symptoms

Background: Alexithymia is a personality construct involving difficulties identifying and verbalizing feelings, and an externally oriented thinking style. There is preliminary evidence for alexithymia subtypes that may carry different risk profiles for psychiatric illness. The aim of this study was to gain support for the existence of alexithymia subtypes and further characterize their clinical relevance. Methods: To identify possible subtypes, a cluster analysis was conducted for individuals with high alexithymic traits (N = 113). Current depressive and anxiety symptoms, self-reported psychiatric medical history, and self reported early life adversity were compared between subtypes. The cluster analysis was replicated with the low (N = 2471) and moderate (N = 290) alexithymia groups. Results: We identified two alexithymia subtypes. Compared to type A, type B alexithymia was associated with higher levels of difficulties in identifying feelings, and was more strongly associated with current depressive (Cohen's d = 0.77, p < 0.001) and anxiety symptoms (Cohen's d = 0.82, p < 0.001), and self-reported early life adversity (Cohen's d 0.42, p = 0.048). Compared to type A, type B alexithymia was also associated with a higher prevalence of self-reported diagnosis of major depressive- (30.2% vs. 8.3%) and anxiety disorder (18.9% vs. 3.3%). Conclusions: The results of this study support the hypothesis of alexithymia subtypes, and add support to the growing evidence showing that alexithymia is likely a heterogeneous and dimensional phenomenon. The subtype (type B) with most pronounced difficulties in identifying feelings may be associated with a higher risk for psychiatric illness compared to type A alexithymia, and may exhibit a more severe history of early life adversity.