Illness identity, experience, and perceptions as longitudinal predictors of adherence behaviors and health outcomes in adolescent Cystic Fibrosis

People with Cystic Fibrosis (CF) experience considerable symptom and treatment burden on a daily basis. Airway Clearance Therapy (ACT) is one of the most time-consuming treatments and has low rates of adherence. Adherence behaviors are important to address in adolescence, as patients begin to take over responsibility from parents. However, adolescents with CF experience unique barriers to treatment adherence. Their symptoms and treatments can disrupt developmentally-appropriate pursuits like peer relationships and affect identity development. Illness identity describes distinct ways in which chronic illness can be integrated into a patient’s identity, with varying effects on mental health and treatment adherence. Patients’ experience of CF also alters their treatment adherence by affecting beliefs about the necessity and efficacy of their treatments. As such, improving treatment adherence may require considering not only the adolescents’ illness- and treatment-related beliefs, but also the experiences that have informed those beliefs. This study of 120 adolescents with CF recruited from a Central Texas medical center uses regression to determine whether past illness-related health, represented by average pulmonary function, predicts ACT adherence, and whether illness identity and treatment beliefs (Beliefs) mediate the relationship. The study also uses regression to assess whether ACT adherence mediates the relationship between past Beliefs and future pulmonary function. This study would allow clinicians to identify adolescents with uncontrolled illness-related health as at higher risk for developing future maladaptive Beliefs that could affect treatment adherence. It would also provide guidance on targeted interventions for adolescents with chronically poor treatment adherence that take their unique developmental stage into account.