Background
The 10/66 dementia research group
The demographic and health transitions
Dementia in developing countries
Global burden
Developed/developing country differences
Dementia aetiology
Dementia, cardiovascular risk factors and cardiovascular disease
Nutritional factors
Ethnic differences and research in admixed populations
Dementia
Stroke, heart disease and CVD risk factors
Admixture proportions
Aims of the 10/66 population-based research programme
Primary objectives
Secondary objectives
1. Mortality
2. Stroke
3. Depression
Methods/design
The prevalence survey
Study design
Country (PI) | Catchment area | Target sample | Interviews completed | Response % | DNA | Fasting blood sample | Start/finish |
---|---|---|---|---|---|---|---|
Cuba (Llibre) | Havana (urban) | 2100 | 2100 | 94% | Yes | Yes | 6/03 12/05 |
Matanzas (urban) | 900 | 900 | |||||
Brazil (Menezes) | Sao Paulo (urban) | 2000 | 2000 | 93% | Yes | Yes | 5/03 7/05 |
Dominican Rep. (Acosta) | Santo Domingo (urban) | 2000 | 2000 | 95% | Blood (EDTA at -20 C) | Yes | 11/03 12/05 |
Venezuela (Salas) | Caracas (urban) | 2000 | 2026 | 79.6% | Yes | Yes | 9/04 6/06 |
Mexico (Sosa) | Mexico city (urban) | 1000 | 1000 | 85.1% | Blotting paper | Yes | 1/06 10/06 |
Morelos/Higalgo (rural) | 1500 | 1000 | |||||
Peru (Guerra) | Lima (urban) | 1500 | 1431 | 60% | Blotting paper | Yes | 4/05 6/06 |
Canete (rural) | 500 | 569 | |||||
Argentina (Arizaga) | Buenos Aires (urban) | 1200 | 0 | incomplete | Yes | Yes | 4/05 6/06 |
Canuelas (rural) | 800 | 800 | |||||
China (Li/Huang) | Xicheng (Beijing, urban) | 1000 | 1000 | 83% | No | No | 3/04 9/05 |
Daxin (rural) | 1000 | 1001 | |||||
India (Krishnamoorthy) | Chennai (urban) | 1000 | 1005 | 72% | No | No | 2/04 12/05 |
India (KS Jacob) | Vellore (rural) | 1000 | 1000 | 98% | No | No | 3/04 8/05 |
Nigeria (Richard Ukawa) | Anambra (rural) | 1000 | 500 | incomplete | No | No | |
9 countries | 13 catchment areas | 20,000 | 17725 |
Settings
Catchment areas and sample registration
Preparation
Interviews and measures
1) Outcome – The diagnosis of dementia
2) Blood sample protocol
3) Genotyping
4) Principal exposures – environmental
4.1 Sociodemographic status
4.2 Health status
4.3 Biological assessments
4.4 Risk exposures
5) Measures of care arrangements, and impact of providing care on caregivers
Resources/training/quality control
Data management
Ethical issues
Incidence phase
Tracing participants
Protocol
Interviews and data collection
Mortality
Stroke
New retrospective exposure data (not collected at baseline)
New biochemical assays
Analyses
Description of incidence
Hypothesis testing
Power and sample size considerations
Country | Baseline sample | Dementia at baseline | Free of dementia at baseline | Available for FU interview1
| Person years | Deaths | Incident dementia2
| Incident strokes |
---|---|---|---|---|---|---|---|---|
Cuba | 3000 | 330 | 2670 | 1994 | 6730 | 509 | 55 | 45 |
DR | 2000 | 220 | 1780 | 1329 | 4488 | 339 | 37 | 30 |
Venezuela | 2000 | 200 | 1800 | 1345 | 4490 | 339 | 37 | 30 |
Mexico | 2000 | 200 | 1800 | 1381 | 2906 | 295 | 30 | 25 |
Peru | 2000 | 200 | 1800 | 1381 | 2906 | 295 | 30 | 25 |
Argentina | 2000 | 200 | 1800 | 1381 | 2906 | 295 | 30 | 25 |
Sub-total3
| 13000 | 1350 | 11650 | 8811 | 24426 | 2072 | 219 | 180 |
China | 2162 | 137 | 2025 | 1513 | 5105 | 366 | 42 | 30 |
TOTAL | 15000 | 1300 | 11700 | 10324 | 29531 | 2438 | 261 | 210 |
Minimum Hazard Ratio to be detected | Power for detecting association with 10% exposure prevalence | Power for detecting an association with 20% exposure prevalence | ||
---|---|---|---|---|
Outcome1,2
| Dementia | Stroke | Dementia | Stroke |
2.5 | 100% | 99.8% | 100% | 100% |
2.0 | 96.4% | 90.9% | 99.8% | 98.8% |
1.8 | 86.0% | 75.8% | 97.5% | 92.8% |
1.5 | 48.8% | 39.3% | 71.0% | 59.5% |
Exposure Prevalence Power | 5% | 10% | 15% | 40% |
---|---|---|---|---|
80% | 2.4 | 2.0 | 1.8 | 1.6 |
90% | 2.7 | 2.2 | 2.0 | 1.7 |