How representative is the ACTIVE sample? A statistical comparison of the ACTIVE sample and the HRS sample

Factors Associated with Participation in a Multidomain Web-Based Dementia Prevention Trial: Evidence from Maintain Your Brain (MYB)

BACKGROUND

The Maintain Your Brain (MYB) trial aims to prevent cognitive decline and dementia through multidomain, web-based risk-reduction. To facilitate translation, it is important to understand drivers of participation.

OBJECTIVE

To describe characteristics associated with participation in MYB.

METHODS

This was an observational ancillary study of MYB, a randomized controlled trial nested within the 45 and Up Study in New South Wales, Australia. We linked 45 and Up Study survey and MYB participation data. The study cohort comprised 45 and Up Study participants, aged 55-77 years at 1 January 2018, who were invited to participate in MYB. 45 and Up Study participant characteristics and subsequent MYB consent and participation were examined.

RESULTS

Of 98,836 invited, 13,882 (14%) consented to participate and 6,190 participated (6%). Adjusting for age and sex, a wide range of factors were related to participation. Higher educational attainment had the strongest relationship with increased MYB participation (university versus school non-completion; AdjOR = 5.15; 95% CI:4.70-5.64) and lower self-rated quality of life with reduced participation (Poor versus Excellent: AdjOR = 0.19; 95% CI:0.11-0.32). A family history of Alzheimer's disease was related to increased participation but most other dementia risk factors such as diabetes, obesity, stroke, high blood pressure, and current smoking were associated with reduced participation.

CONCLUSION

Higher socio-economic status, particularly educational attainment, is strongly associated with engagement in online dementia prevention research. Increasing population awareness of dementia risk factors, and better understanding the participation barriers in at-risk groups, is necessary to ensure online interventions are optimally designed to promote maximum participation.

Disparities in the participation and adherence of older adults in lifestyle-based multidomain dementia prevention and the motivational role of perceived disease risk and intervention benefits: an observational ancillary study to a randomised controlled trial

Background

Preventive interventions for dementia are urgently needed and must be tested in randomised controlled trials (RCTs). Selection (volunteer) bias may limit efficacy, particularly in trials testing multidomain interventions and may also be indicative of disparities in intervention uptake in real-world settings. We identified factors associated with participation and adherence in a 3-year RCT of multidomain lifestyle intervention and/or omega-3 supplementation for prevention of cognitive decline and explored reasons for (non-) participation.

Methods

Ancillary study during recruitment and follow-up of the 3-year Multidomain Alzheimer Preventive Trial (MAPT) conducted in in 13 memory centres in France and Monaco, involving 1630 community-dwelling dementia-free individuals aged ≥ 70 who were pre-screened for MAPT (1270 participated in MAPT; 360 declined to participate).

Results

Response rates were 76% amongst MAPT participants and 53% amongst non-participants. Older individuals (odds ratio 0.94 [95% confidence interval 0.91–0.98] and those with higher anxiety (0.61 [0.47–0.79]) were less likely to participate in the trial. Those with higher income (4.42 [2.12–9.19]) and family history (1.60 [1.10–2.32]) or greater fear (1.73 [1.30–2.29]) of dementia were more likely to participate, as were those recruited via an intermediary (e.g. pension funds, local Alzheimer’s associations, University of the 3rd Age, sports clubs) (2.15 [1.45–3.20]). MAPT participants living in larger towns (0.71 [0.55–0.92]) and with higher depressive symptoms (0.94 [0.90–0.99]) were less likely to adhere to the interventions. Greater perceived social support (1.21 [1.03–1.43]) and cognitive function (1.37 [1.13–1.67]) predicted better adherence. Descriptively, the most frequent reasons for accepting and refusing to participate were, respectively, altruism and logistical constraints, but underlying motivations mainly related to (lack of) perceived benefits.

Conclusions

Disparities in uptake of health interventions persist in older age. Those most at risk of dementia may not participate in or adhere to preventive interventions. Barriers to implementing lifestyle changes for dementia prevention include lack of knowledge about potential benefits, lack of support networks, and (perceived) financial costs.

Trial registration

NCT00672685 (ClinicalTrials.gov)

Supplementary Information

The online version contains supplementary material available at 10.1186/s13195-021-00904-6.

Cohort Profile: Hong Kong Department of Health Elderly Health Service Cohort

The Department of Health Elderly Health Service Cohort in Hong Kong was set up to promote understanding of ageing in a global context, to exploit the role of Hong Kong as a sentinel for populations currently experiencing very rapid economic development, to provide a developed non-Western 'social laboratory' where empirically derived hypotheses can be tested and to leverage the different patterns of common chronic diseases between East and West to generate novel hypotheses about their determinants. The initial cohort enrolled from July 1998 to the end of December 2001 includes 66 820 people aged 65 years or older, forming about 9% of the population of this age. A comprehensive health assessment was made at enrollment and then repeated regularly on an ongoing basis. The health assessment included a comprehensive assessment of lifestyle, social circumstances, physical health and mental health, including an assessment of cognition and depressive symptoms. Health services use and deaths have been obtained by record linkage and confirmed, where necessary, by telephone interview. Currently, the data are not publicly available; we would welcome collaborations and research proposals.

Recruitment and baseline characteristics of participants in the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER)-a randomized controlled lifestyle trial

Our aim is to describe the study recruitment and baseline characteristics of the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) study population. Potential study participants (age 60-77 years, the dementia risk score ≥ 6) were identified from previous population-based survey cohorts and invited to the screening visit. To be eligible, cognitive performance measured at the screening visit had to be at the mean level or slightly lower than expected for age. Of those invited (n = 5496), 48% (n = 2654) attended the screening visit, and finally 1260 eligible participants were randomized to the intervention and control groups (1:1). The screening visit non-attendees were slightly older, less educated, and had more vascular risk factors and diseases present. The mean (SD) age of the randomized participants was 69.4 (4.7) years, Mini-Mental State Examination 26.7 (2.0) points, systolic blood pressure 140.1 (16.2) mmHg, total serum cholesterol 5.2 (1.0) mmol/L for, and fasting glucose 6.1 (0.9) mmol/L for, with no difference between intervention and control groups. Several modifiable risk factors were present at baseline indicating an opportunity for the intervention. The FINGER study will provide important information on the effect of lifestyle intervention to prevent cognitive impairment among at risk persons.