The role of engagement in affecting non-pharmacological intervention outcomes of people with dementia receiving cognitive stimulation therapy

Abstract

Background: Dementia causes participants’ cognitive decline that interferes with their daily functioning. Considering its high prevalence worldwide and no cure available for its underlying disease, the medications and non-pharmacological interventions addressing symptoms control and overall the quality of life are essential for persons with dementia (PwD). Cognitive stimulation therapy (CST), emphasising participation in information processing and person-centred communication, is the only evidence-based non-pharmacological intervention recommended by clinical guidelines at the national level. Participants involving in the 14-session themed group work delivered by trained facilitators in CST consistently benefit in cognition and quality of life. However, the benefits vary among individuals, and the mechanism of maximising the intervention effectiveness is unclear. Engagement, a state of being occupied by meaningful external stimuli, may be the missing link we overlooked. Objectives: To investigate whether engagement of PwD in CST affects their degree of benefits in clinical outcomes and what factors contribute to their engagement. Methods: The study uses a mixed-method design. A total of 113 PwD enrolling in the observational study of engagement were from the community care centre, day care centre, and residential care units of older adults in Hong Kong. Constructive engagement, defining as the motor or verbal behaviour exhibited in purposeful activities, was assessed by time sampling of six 5-minute observation windows during CST sessions. It included two subtypes (i.e., collective and individual constructive engagement). The time proportion of constructive engagement and its subtypes quantified PwD's engagement level in CST. The clinical outcomes of cognition, quality of life for PwD, communication ability, and relationship quality with group facilitators, were repeatedly measured at the baseline and post-test. After CST, group facilitators (N=12) received individual in-depth interviews, which were audio-taped and transcribed verbatim for thematic analysis. Results: The multivariate regressions showed that individual constructive engagement predicted PwD’s cognitive benefits (B = 11.831, β = -.143, p = .008) and carer-rated quality of life for PwD (B = -9.574, β = -.212, p = .014). Two significant predictors for the improvement of communication ability were PwD’s constructive engagement (B = -8.790, β = -.202, p = .007) and collective constructive engagement (B = -9.121, β = -.250, p = .006). Their constructive engagement in CST had no association with the quality of relationships with group facilitators. Constructive engagement of PwD in CST increased gradually at the early phase and stabilised at a level around the middle phase of the group work. Three modifiable factors are probably helpful to enhance PwD’s engagement, including (1) diverse activities tailoring to PwD’s residual capabilities, interests, and strengths, (2) techniques of facilitation for enhancing PwD’s positive experiential learning, and (3) the use of group dynamics. Conclusions: Individual and collective constructive engagement are the indicators for PwD’s cognitive benefits and communication ability, respectively. Constructive engagement showed the potential to be generalised as the shared mechanism of maximising the effectiveness. Identified factors enhancing constructive engagement provided the practical framework on implementing person-centred dementia care from design to delivery of non-pharmacological interventions. The behavioural approach has its limitations to capture the nature of PwD’s mental engagement. Further research may focus on generalising the predictive power of engagement on clinical outcomes and improving the efficiency of maximising the effectiveness in diverse non-pharmacological interventions for dementia. The better measurement of PwD’s engagement in non-pharmacological interventions needs to be developed.