Personal and Illness Identity in Youth With Type 1 Diabetes: Developmental Trajectories and Associations

Objective: Having Type 1 diabetes (T1D) may complicate the normative developmental task of personal identity formation in adolescence and emerging adulthood. Besides exploring and committing to identity choices in different life domains, youth with T1D need to integrate their illness into their identity, a process labeled as illness identity. The present study examined whether youth with T1D belonging to different personal identity trajectory classes developed differently on four illness identity dimensions (acceptance, enrichment, engulfment, rejection). Method: This four-wave longitudinal study over a 3-year period used self-report questionnaires to examine how personal identity trajectory classes were related to illness identity over time in youth with T1D (baseline: n = 558; 54% female; age range = 14-25 years). Personal identity trajectory classes were identified using latent class growth analysis. Differential development of the four illness identity dimensions among these personal identity trajectory classes was examined using multigroup latent growth curve modeling. Results: Five personal identity trajectory classes were identified: achievement, foreclosure, moratorium, carefree diffusion, and troubled diffusion. Individuals in achievement and foreclosure displayed highest levels of diabetes integration (i.e., high levels of acceptance and enrichment; low levels of engulfment and rejection), whereas individuals in troubled diffusion displayed lowest levels of illness integration (i.e., low levels of acceptance and enrichment; high levels of engulfment and rejection). Conclusions: The present study confirms that personal identity development relates to illness identity development over time in youth with T1D. Understanding the intricate link between personal and illness identity may help clinicians to tailor their interventions to patients' individual needs.