Mortality rates in community-dwelling Tanzanians with dementia and mild cognitive impairment: a 4-year follow-up study.
BACKGROUND
we have previously conducted a community-based prevalence study of dementia in older adults living in the rural Hai district of Tanzania. The aim of this study was to record mortality rates at 4 years post-diagnosis, of those with dementia, mild cognitive impairment (MCI) and no cognitive impairment.


METHODS
during Phase I of the prevalence study, 1,198 people aged 70 years and over were screened, and a stratified sample of 296 was assessed for the presence of dementia or MCI in Phase II. Seventy-eight people had dementia and 46 had MCI. Four years after diagnosis, we attempted to follow-up all those seen in Phase II and record all deaths.


RESULTS
of the 296, follow-up data were available for 287 (97.0%), including 77 with dementia and 45 with MCI. Of the 172 with no cognitive impairment, 165 (95.9%) were followed up and a sample of 89 people selected as representative of the background population. Forty-eight people with dementia (62.3%), 19 with MCI (42.2%) and 11 with no cognitive impairment (12.4%) had died at 4-year follow-up. After adjusting for the effects of age, gender and education, the hazard ratio was 6.33 (95% CI 3.19-12.58) for dementia and 3.57 (95% CI 1.64-7.79) for MCI relative to people with no cognitive impairment. Mortality rates were highest in those with vascular dementia.


CONCLUSIONS
dementia and MCI were associated with excess mortality relative to those with no cognitive impairment.
Northumbria Healthcare NHS Foundation Trust, Department of Medicine, North Tyneside General Hospital, Tyne and Wear, UK Institute of Neuroscience, Newcastle University, Newcastle Upon Tyne, UK.
Stella-Maria
SM
Paddick
Hai District Hospital, Boman'gombe, Kilimanjaro, Tanzania.
Aloyce
A
Kisoli
Northumbria Healthcare NHS Foundation Trust, Department of Medicine, North Tyneside General Hospital, Tyne and Wear, UK Institute for Ageing, Newcastle University, Newcastle-upon-Tyne, UK.
Catherine L
CL
Dotchin
Northumbria Healthcare NHS Foundation Trust, Department of Medicine, North Tyneside General Hospital, Tyne and Wear, UK.
William K
WK
Gray
District Medical Office, Hai District Hospital, Boman'gombe, Hai, Tanzania.
Paul
P
Chaote
South Devon Healthcare NHS Foundation Trust, Torquay, UK.
Anna
A
Longdon
Northumbria Healthcare NHS Foundation Trust, Department of Medicine, North Tyneside General Hospital, Tyne and Wear, UK Institute of Health and Society, Newcastle University, Newcastle upon Tyne, UK.
Richard W
RW
Walker
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D060825:Cognitive Dysfunction / Q000175:diagnosis / Q000401:mortality*; D003704:Dementia / Q000175:diagnosis / Q000401:mortality*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D015577:Geriatric Assessment / Q000379:methods*; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011159:Population Surveillance / Q000379:methods*; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D013636:Tanzania / Q000453:epidemiology; D013997:Time Factors
Africa; Alzheimer's disease; Tanzania; dementia; mortality; older people