A new study published in The Lancet Healthy Longevity has found that a coach-supported mobile health (mHealth) intervention can help reduce dementia risk factors among underserved populations. However, the low response rates raise concerns about the effectiveness of technological approaches in reaching those most in need and improving population health on a large scale.
With dementia prevalence projected to exceed 150 million globally by 2050, managing risk factors in underserved populations could significantly reduce dementia cases.
About the study
The research, involving Cambridge Public Health researchers, targeted individuals aged 55-75 years from low socioeconomic backgrounds in the UK and the general population in China.
Conducted between January 2021 and April 2023, the study involved 1488 participants. Some participants received the mHealth intervention while others served as a control group. The intervention aimed to help participants manage seven dementia risk factors: overweight, unhealthy diet, insufficient physical activity, smoking, hypertension, dyslipidemia, and diabetes.
The mHealth intervention
The mHealth app was developed with input from the target population and health coaches in the UK. It featured:
- Goal setting for lifestyle changes
- Reminders to enter health measurements
- An education library and news updates
- Remote access to a health coach trained in motivational interviewing and lifestyle behaviour change
Participants in the control group received an app containing the education library, but they did not have access to a health coach.
Key findings
Improved dementia risk scores: After an average follow-up of 16 months, the intervention group showed a modest but significant improvement in their CAIDE risk score, a measure used to predict dementia risk, compared to the control group.
Reduction in risk factors: the intervention led to a reduction in the number of uncontrolled risk factors relating to blood pressure, BMI, total cholesterol, physical activity, diet, and smoking.
Low response rate in the UK: The overall response rate to take part in the research was only 5% in the UK, which will have introduced selection bias towards people already motivated to introduce changes in their lifestyles.
Impact on inequalities
The low response rates in the UK highlight significant challenges in the research. Technological solutions while potentially effective, might unintentionally increase inequalities by engaging those already interested in health improvements and missing those who need the most help. Without a broader approach to improving public health on a larger scale, such technological interventions cannot achieve the desired impact.
Professor Carol Brayne, co-director of Cambridge Public Health and one of the study’s authors commented:
“Whilst this rigorous trial demonstrated the proof of principle for improvement, it also highlighted the challenges of implementing individualised approaches on a larger scale. The findings here align with the established evidence base that to achieve large scale change in population health, efforts at societal and structural levels are more likely to be effective. Addressing upstream determinants of inequality, which in itself leads to worse dementia risk profiles in many communities, is particularly important”
Future implications
There are two potential implications. First, continuing to pursue this type of individualised approach could indicate the need for a larger randomized controlled trial with long-term follow-up to determine its impact on cognitive decline and dementia prevention. Many UK participants appreciated the coach more than the technology, itself and important observation. If proven effective for further diverse populations beyond China, this type of supported mobile health intervention might provide affordable and universal strategies for high-risk populations worldwide.
Second, much evidence points towards structural influences on dementia risk. Research should aim to enhance the evidence base for dementia risk reduction at scale and for whole communities.
About the research
The research was part of the Prevention of dementia using mobile phone applications (PRODEMOS), a multinational, prospective, randomised, open-label, blinded endpoint clinical trial with 12 to 18 months' intervention and follow-up, using a type II hybrid effectiveness–implementation design with a dual focus on effectiveness and implementation outcomes.