Purpose of review: Treatment nonadherence is a common problem, yet adherence to treatments is important for the successful management of cystic fibrosis (CF). Previous work has concentrated on rates of adherence in children and adults using self-report questionnaires. Recent studies have employed new measurement methods and evaluated various treatment components. It is important to understand the factors that impede and facilitate adherence in order that research and clinical practice can improve adherence rates.

Recent findings: There is a high perceived treatment burden in CF. Rates of adherence vary according to the treatment and the measurement method. Reasons for nonadherence are numerous. Even with technology designed to reduce treatment time, adherence to nebulized antibiotics is still poor. Nonadherence is a particular issue in adolescence and there is evidence that girls are less adherent than boys, leading to poorer lung function. Patients who have a cohesive and balanced family life may be better able to incorporate CF treatments. Treatment beliefs and the perception of treatment effectiveness are important determinants of adherence.

Summary: Research needs to move forward to understand how to help patients to improve their adherence and to assist healthcare professionals in supporting them. There is a consensus that tailored interventions are essential. In addition, it is important to understand adherence behaviours over time in order to recognize specific periods during a person's life when adherence is more difficult to achieve.