Negative illness perceptions are related to more fatigue among haematological cancer survivors: a PROFILES study

Objectives: The common sense model provides a theoretical framework for understanding substantial fatigue among (haematological) cancer survivors based on their illness perceptions. We therefore examined the associations between modifiable illness perceptions and substantial fatigue while controlling for sociodemographic, clinical, and psychological factors (symptoms of depression and anxiety) among haematological cancer survivors.Methods: Data from the population-based PROFILES registry were used. Survivors diagnosed between 1999 and 2013 with Hodgkin lymphoma (N = 164), non-Hodgkin lymphoma (N = 655) and chronic lymphocytic leukaemia (N = 174) were included. Survivors completed the Brief Illness Perception Questionnaire (B-IPQ), the Fatigue Assessment Scale (FAS), and Hospital Anxiety and Depression Scale (HADS). Multivariable logistic regressions analyses were performed for the total group and three haematological cancers separately relating illness perceptions to substantial fatigue (>21 FAS).Results: Haematological cancer survivors with illness perceptions that represent more negative consequences (consequences, OR = 1.27; 95%CI = 1.13-1.42); attribute more symptoms to their illness (identity, OR = 1.29; 95%CI = 1.17-1.43); and have a poorer illness understanding (coherence, 1.13; 1.04-1.22) were more often substantially fatigued. For the remaining five illness perceptions, no significant association was found. Non-Hodgkin lymphoma survivors who reported a poor illness understanding (coherence, OR = 1.35; 95% CI = 1.06-1.72) and chronic lymphocytic leukaemia survivors who reported that treatment can control (OR = 1.25; 95%CI = 1.01-1.55) the illness experienced more often substantial fatigue.Conclusion: Those who experience more consequences of their disease, attribute more symptoms to their illness, and have a poorer illness understanding, have a higher risk to experience substantial levels of fatigue even years after diagnosis. Psychological interventions changing these illness perceptions may be beneficial in reducing fatigue among haematological cancer survivors.