Effectiveness of Cognitive Stimulation Therapy (CST) for mild to moderate dementia: A systematic literature review and meta-analysis of randomised control trials using the original CST protocol.

AIMS: We aimed to conduct a systematic literature review and meta-analysis to evaluate the efficacy of the original 14 session Cognitive Stimulation Therapy (CST) protocol in improving cognitive function and related outcomes in people with mild to moderate dementia. METHODS: Four databases were searched, up to May 2023, for randomized controlled trials of CST using the original protocol. Pre- and post-test means and measures of dispersion for intervention and control groups were extracted for each reported outcome and used to calculate effect sizes. Effect sizes were grouped by outcome and pooled in inverse variance weighted random effects models. RESULTS: Twelve studies were identified as meeting inclusion criteria. Of these, ten were given either a 'high' or 'medium' quality rating. The pooled results indicated that CST had a significant beneficial impact on global cognition, language, working memory, depression, neuropsychiatric symptoms, communication, self-reported quality of life and severity of dementia. CONCLUSIONS: CST as delivered in adherence to the original 14-session protocol is an efficacious treatment for mild to moderate dementia with improvements in cognition, affective symptoms and quality of life demonstrated from global trials.

Predictors of primary care psychological therapy outcomes for depression and anxiety in people living with dementia: evidence from national healthcare records in England.

BACKGROUND: Psychological therapies can be effective in reducing symptoms of depression and anxiety in people living with dementia (PLWD). However, factors associated with better therapy outcomes in PLWD are currently unknown. AIMS: To investigate whether dementia-specific and non-dementia-specific factors are associated with therapy outcomes in PLWD. METHOD: National linked healthcare records were used to identify 1522 PLWD who attended psychological therapy services across England. Associations between various factors and therapy outcomes were explored. RESULTS: People with frontotemporal dementia were more likely to experience reliable deterioration in depression/anxiety symptoms compared with people with vascular dementia (odds ratio 2.98, 95% CI 1.08-8.22; P = 0.03) or Alzheimer's disease (odds ratio 2.95, 95% CI 1.15-7.55; P = 0.03). Greater depression severity (reliable recovery: odds ratio 0.95, 95% CI 0.92-0.98, P < 0.001; reliable deterioration: odds ratio 1.73, 95% CI 1.04-2.90, P = 0.04), lower work and social functioning (recovery: odds ratio 0.98, 95% CI 0.96-0.99, P = 0.002), psychotropic medication use (recovery: odds ratio 0.67, 95% CI 0.51-0.90, P = 0.01), being of working age (recovery: odds ratio 2.03, 95% CI 1.10-3.73, P = 0.02) and fewer therapy sessions (recovery: odds ratio 1.12, 95% CI 1.09-1.16, P < 0.001) were associated with worse therapy outcomes in PLWD. CONCLUSIONS: Dementia type was generally not associated with outcomes, whereas clinical factors were consistent with those identified for the general population. Additional support and adaptations may be required to improve therapy outcomes in PLWD, particularly in those who are younger and have more severe depression.

Associations between psychological intervention for anxiety disorders and risk of dementia: a prospective cohort study using national health-care records data in England.

BACKGROUND: Meta-analyses support an association between anxiety in older adulthood and dementia. The aim of this study was to use routinely collected health data to test whether treatment of anxiety disorders through psychological intervention is associated with a lower incidence of dementia. METHODS: In this prospective cohort study, data from nationally provided psychological therapy services in England termed Improving Access to Psychological Therapies from 2012 to 2019 were linked to medical records, including dementia diagnoses as defined by the tenth edition of the International Classification of Diseases, up to 8 follow-up years later. Inclusion criteria were as follows: (1) patients who were aged 65 years and older; (2) patients with a probable anxiety disorder; and (3) those with no previous or current diagnosis of dementia. Cox proportional hazards models were constructed to test whether reliable improvement in anxiety following psychological intervention was associated with future dementia incidence. The primary outcome was all-cause dementia and cases were identified using ICD-10 dementia codes from Hospital Episode Statistics, Mental Health Services Dataset, and mortality data. For main analyses, hazards ratios (HRs) are presented. FINDINGS: Data from 128 077 people aged 65 years and older attending a nationally provided psychological intervention service in England were linked to medical records. 88 019 (69·0%) of 127 064 participants with available gender data were women and 39 585 (31·0%) were men. 111 225 (95·9%) of 115 989 with available ethnicity data were of White ethnicity. The mean age of the sample was 71·55 years (SD 5·69). Fully adjusted models included data from 111 958 people after 16 119 were excluded due to missing data on key variables or covariates. 4510 (4·0%) of 111 958 participants had a dementia diagnosis. The remaining 107 448 (96·0%) were censored either at date of death or when the final follow-up period available for analyses was reached. People who showed reliable improvement in anxiety had lower rates of later dementia diagnosis (3·9%) than those who did not show reliable improvement (5·1%). Reliable improvement in anxiety following psychological intervention was associated with reduced incidence of all-cause dementia (HR 0·83 [95% CI 0·78-0·88]), Alzheimer's disease (HR 0·85 [0·77-0·94]), and vascular dementia (HR 0·80 [0·71-0·90]). Effects did not differ depending on anxiety disorder diagnosis. INTERPRETATION: Results showed that reliable improvement in anxiety from psychological therapy was associated with reduced incidence of future dementia. There are multiple plausible explanations for this finding and further research is needed to distinguish between these possibilities. Missing data in the sample limit reliability of findings. FUNDING: Alzheimer's Society, Medical Research Council, Wellcome Trust, and UCLH National Institute for Health and Care Research Biomedical Research Centre.

Associations between psychological therapy outcomes for depression and incidence of dementia.

BACKGROUND: Depression is an important, potentially modifiable dementia risk factor. However, it is not known whether effective treatment of depression through psychological therapies is associated with reduced dementia incidence. The aim of this study was to investigate associations between reduction in depressive symptoms following psychological therapy and the subsequent incidence of dementia. METHODS: National psychological therapy data were linked with hospital records of dementia diagnosis for 119808 people aged 65+. Participants received a course of psychological therapy treatment in Improving Access to Psychological Therapies (IAPT) services between 2012 and 2019. Cox proportional hazards models were run to test associations between improvement in depression following psychological therapy and incidence of dementia diagnosis up to eight years later. RESULTS: Improvements in depression following treatment were associated with reduced rates of dementia diagnosis up to 8 years later (HR = 0.88, 95% CI 0.83-0.94), after adjustment for key covariates. Strongest effects were observed for vascular dementia (HR = 0.86, 95% CI 0.77-0.97) compared with Alzheimer's disease (HR = 0.91, 95% CI 0.83-1.00). CONCLUSIONS: Reliable improvement in depression across psychological therapy was associated with reduced incidence of future dementia. Results are consistent with at least two possibilities. Firstly, psychological interventions to improve symptoms of depression may have the potential to contribute to dementia risk reduction efforts. Secondly, psychological therapies may be less effective in people with underlying dementia pathology or they may be more likely to drop out of therapy (reverse causality). Tackling the under-representation of older people in psychological therapies and optimizing therapy outcomes is an important goal for future research.