Fear of progression in chronic illnesses other than cancer: a systematic review and meta-analysis of a transdiagnostic construct.

Fear of cancer recurrence (FCR) is the most common psychosocial issue amongst cancer survivors. However, fear of progression (FoP) has rarely been studied outside of the cancer context. This review aimed to: (1) meta-synthesise qualitative studies of FoP in illnesses other than cancer; and (2) quantify the relationship between FoP and anxiety, depression, and quality of life (QoL) in non-cancer chronic illnesses. We identified 25 qualitative and 11 quantitative studies in a range of chronic illnesses. Participants described fears of progression and recurrence of their illness, including fears of dying, and fears of becoming a burden to family. Fears were often triggered by downward comparison (i.e., seeing people worse off than themselves). Participants coped in different ways, including by accepting the illness or seeking knowledge. Those for whom these fears caused distress reported hypervigilance to physical symptoms and avoidance. Distress, and seeking information, were associated with adherence. In quantitative analyses, FoP was moderately associated with QoL, and strongly associated with anxiety and depression. These results suggest that FoP in illnesses other than cancer is similar to FCR. FoP appears to be an important transdiagnostic construct associated with distress. Evidence-based FCR interventions could be adapted to better manage FoP in other illnesses.