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A longitudinal study of cognitive decline in rural Tanzania: rates and potentially modifiable risk factors

Published online by Cambridge University Press:  21 March 2018

Jessica Heward ,
Lydia Stone ,
Stella-Maria Paddick ,
Sarah Mkenda ,
William K. Gray ,
Catherine L. Dotchin ,
John Kissima ,
Cecilia Collingwood ,
Bernadetha Swai  and
Richard W. Walker
Jessica Heward
Affiliation:
The Medical School, Newcastle University, Newcastle upon Tyne, UK
Lydia Stone
Affiliation:
The Medical School, Newcastle University, Newcastle upon Tyne, UK
Stella-Maria Paddick
Affiliation:
Northumbria Healthcare NHS Foundation Trust, North Tyneside General Hospital, North Shields, UK Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
Sarah Mkenda
Affiliation:
Kilimanjaro Christian Medical University College, Moshi, Tanzania
William K. Gray
Affiliation:
Northumbria Healthcare NHS Foundation Trust, North Tyneside General Hospital, North Shields, UK
Catherine L. Dotchin
Affiliation:
Northumbria Healthcare NHS Foundation Trust, North Tyneside General Hospital, North Shields, UK Institute of Health and Society, Newcastle University, Newcastle upon Tyne, UK
John Kissima
Affiliation:
Hai District Medical Centre, Boman'gombe, Kilimanjaro Region, Tanzania
Cecilia Collingwood
Affiliation:
The Medical School, Newcastle University, Newcastle upon Tyne, UK
Bernadetha Swai
Affiliation:
Hai District Medical Centre, Boman'gombe, Kilimanjaro Region, Tanzania
Richard W. Walker*
Affiliation:
Northumbria Healthcare NHS Foundation Trust, North Tyneside General Hospital, North Shields, UK Institute of Health and Society, Newcastle University, Newcastle upon Tyne, UK
*
Correspondence should be addressed to: Richard W. Walker, Northumbria Healthcare NHS Foundation Trust, North Tyneside General Hospital, North Shields, UK. Phone: +44 191 293 2709. Email: richard.walker@nhct.nhs.uk.
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Abstract

Background:

The number of people living with dementia in sub-Saharan Africa (SSA) is expected to increase rapidly in the coming decades. However, our understanding of how best to reduce dementia risk in the population is very limited. As a first step in developing intervention strategies to manage dementia risk in this setting, we investigated rates of cognitive decline in a rural population in Tanzania and attempted to identify associated factors.

Methods:

The study was conducted in the rural Hai district of northern Tanzania. In 2014, community-dwelling people aged 65 years and over living in six villages were invited to take part in a cognitive screening program. All participants from four of the six villages were followed-up at two years and cognitive function re-tested. At baseline and follow-up, participants were assessed for functional disability, hypertension, and grip strength (as a measure of frailty). At follow-up, additional assessments of visual acuity, hearing impairment, tobacco and alcohol consumption, and clinical assessment for stroke were completed.

Results:

Baseline and follow-up data were available for 327 people. Fifty people had significant cognitive decline at two-year follow-up. Having no formal education, low grip strength at baseline, being female and having depression at follow-up were independently associated with cognitive decline.

Conclusions:

This is one of the first studies of cognitive decline conducted in SSA. Rates of decline at two years were relatively high. Future work should focus on identification of specific modifiable risk factors for cognitive decline with a view to developing culturally appropriate interventions.

Keywords

dementiacognitive impairmentTanzaniasub-Saharan Africalow- and middle-income countries
Type
Original Research Article
Information
International Psychogeriatrics , Volume 30 , Issue 9: Issue Theme: Quality of Care for Frail Older Adults , September 2018 , pp. 1333 - 1343
Copyright
Copyright © International Psychogeriatric Association 2018 

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