Cognitive problems in working cancer survivors:Evaluation of an internet-based cognitive rehabilitation program

Chapter 1: Numerous non-central nervous system (CNS) cancer patients experience cancer-related cognitive problems (CRCP) during and after treatment, potentially affecting work functioning. Identifying effective treatments for CRCP is crucial to ensure employability among cancer survivors. Previous studies suggest cognitive strategy training can alleviate self-perceived CRCP, but evidence is inconclusive and little attention has been given to work-related outcomes. This thesis explores CRCP’s impact on work, treatment options, and evaluates the effectiveness of an internet-based cognitive strategy training program “Niet Rennen Maar Plannen – online” (NRMP-online). Chapter 2: Focus groups, including cancer survivors and professionals, were conducted to gather insights on CRCP at work, coping strategies, and needs. Findings revealed significant impacts of CRCP on work functioning. Cancer survivors employed various strategies to manage CRCP, as did professionals in their attempts to support them. Several needs were identified, including the need for supportive care and enhancement of expertise. Chapter 3: Cancer survivors (n=206) who had applied for work disability benefits after two years of sick leave, were followed over two years. Results showed improvements in self-perceived cognitive functioning, but overall cognitive functioning remained clinically concerning. This suggests that CRCP are persistent among cancer survivors on sick leave. Chapter 4: The association between cognitive functioning and work-related outcomes was evaluated in 279 working cancer survivors with self-reported CRCP. Compared to the norm, a higher incidence of low neuropsychological test performance was found among the sample. Work ability and functioning were associated with self-perceived cognitive functioning, while the association with neuropsychological test performance was less pronounced. Chapter 5: Potential transferability of knowledge from vocational interventions for individuals with chronic diseases to vocational cancer rehabilitation, was evaluated. Results suggested that generic elements of these interventions could be transferred to vocational cancer rehabilitation, although this should be done with caution, and long-term symptoms related to cancer specifically should be taken into account. Chapter 6: Cognitive rehabilitation approaches for CRCP, including cognitive strategy training, retraining, physical exercise, and relaxation techniques, were reviewed. The study concluded that successful cognitive rehabilitation has been achieved in both CNS and non-CNS cancer patients. Several methodological considerations for future research were discussed. Chapter 7: The design of the i-WORC study evaluating NRMP-online’s effectiveness was presented, consisting of two intervention groups (i.e., self-help, basic and therapist-guided, extensive versions of NRMP-online) and a waitlist control group. The primary outcome was the attainment of pre-determined work-related goals. Secondary outcomes included subjective cognitive- and work functioning. Chapter 8: A process evaluation conducted alongside the i-WORC study, focusing on recruitment, reach, dosage, implementation, and participant experiences, was presented. Findings indicated successful implementation of both program versions. Participants and therapists reported generally positive experiences with the program. Chapter 9: Results of the i-WORC study indicated that the therapist-guided, extensive version of NRMP-online had positive, clinically relevant, short- and long-term effect (ES = 0.49 and 0.34, respectively) on attainment of work-related goals in cancer survivors with self-perceived cognitive problems at work. Additional positive effects were observed for recovery needs after a working day (ES = 0.21), vitality (ES = 0.20), and physical role functioning (ES = 0.43). In contrast, the self-help, basic version of NRMP-online did not show a statistically significant positive effect on goal attainment. However, among cancer survivors who met criteria for minimal compliance, borderline significant positive short-term effects on goal attainment were observed for the basic program. Chapter 10: We concluded that the therapist-guided, extensive version of NRMP-online is effective for cancer survivors who experience cognitive problems at work. The self-help, basic version of NRMP-online might be a suitable alternative, but only if individuals adhere to the program sufficiently. Methodological considerations and implications were discussed