Abstract
BACKGROUND: Incidence rates of dementia appear to be declining in high-income countries according to several large epidemiological studies. We aimed to describe declining incident dementia rates across successive birth cohorts in a U.S. population-based sample and to explore the influences of sex and education on these trends. METHODS: We pooled data from two community-sampled prospective cohort studies with similar study aims and contiguous sampling regions: the Monongahela Valley Independent Elders Survey (1987-2001) and the Monongahela-Youghiogheny Healthy Aging Team (2006-Ongoing). We identified four decade-long birth cohorts spanning birth years 1902-1941. In an analysis sample of 3,010 participants (61% women, mean baseline age = 75.7 years, mean follow-up = 7.1 years), we identified 257 cases of incident dementia indicated by a Clinical Dementia Rating of 1.0 or higher. We used Poisson regression to model incident dementia rates by birth cohort, age, sex, education, and interactions of Sex × Cohort and Sex × Education. We further examined whether cohort effects varied by education, testing a Cohort × Education interaction and stratifying the models by education. RESULTS: Compared to the earliest birth cohort (1902-1911), each subsequent cohort had a significantly lower incident dementia rate (1912-1921: incidence rate ratio [IRR] = 0.655, 95% confidence interval [95% CI] = 0.477-0.899; 1922-1931: IRR = 0.387, 95% CI = 0.265-0.564; 1932-1941: IRR = 0.233, 95% CI = 0.121-0.449). We observed no significant interactions of either sex or education with birth cohort. CONCLUSIONS: A decline in incident dementia rates was observed across successive birth cohorts independent of sex, education, and age.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1439-1445 |
| Number of pages | 7 |
| Journal | The journals of gerontology. Series A, Biological sciences and medical sciences |
| Volume | 74 |
| Issue number | 9 |
| DOIs | |
| State | Published - Aug 16 2019 |
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Keywords
- Cognition
- Cognitive aging
- Community-based
- Epidemiology
ASJC Scopus subject areas
- Aging
- Geriatrics and Gerontology
Cite this
Declining Incident Dementia Rates Across Four Population-Based Birth Cohorts. / Sullivan, Kevin J.; Dodge, Hiroko; Hughes, Tiffany F.; Chang, Chung Chou H.; Zhu, Xinmei; Liu, Anran; Ganguli, Mary.
In: The journals of gerontology. Series A, Biological sciences and medical sciences, Vol. 74, No. 9, 16.08.2019, p. 1439-1445.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Declining Incident Dementia Rates Across Four Population-Based Birth Cohorts
AU - Sullivan, Kevin J.
AU - Dodge, Hiroko
AU - Hughes, Tiffany F.
AU - Chang, Chung Chou H.
AU - Zhu, Xinmei
AU - Liu, Anran
AU - Ganguli, Mary
PY - 2019/8/16
Y1 - 2019/8/16
N2 - BACKGROUND: Incidence rates of dementia appear to be declining in high-income countries according to several large epidemiological studies. We aimed to describe declining incident dementia rates across successive birth cohorts in a U.S. population-based sample and to explore the influences of sex and education on these trends. METHODS: We pooled data from two community-sampled prospective cohort studies with similar study aims and contiguous sampling regions: the Monongahela Valley Independent Elders Survey (1987-2001) and the Monongahela-Youghiogheny Healthy Aging Team (2006-Ongoing). We identified four decade-long birth cohorts spanning birth years 1902-1941. In an analysis sample of 3,010 participants (61% women, mean baseline age = 75.7 years, mean follow-up = 7.1 years), we identified 257 cases of incident dementia indicated by a Clinical Dementia Rating of 1.0 or higher. We used Poisson regression to model incident dementia rates by birth cohort, age, sex, education, and interactions of Sex × Cohort and Sex × Education. We further examined whether cohort effects varied by education, testing a Cohort × Education interaction and stratifying the models by education. RESULTS: Compared to the earliest birth cohort (1902-1911), each subsequent cohort had a significantly lower incident dementia rate (1912-1921: incidence rate ratio [IRR] = 0.655, 95% confidence interval [95% CI] = 0.477-0.899; 1922-1931: IRR = 0.387, 95% CI = 0.265-0.564; 1932-1941: IRR = 0.233, 95% CI = 0.121-0.449). We observed no significant interactions of either sex or education with birth cohort. CONCLUSIONS: A decline in incident dementia rates was observed across successive birth cohorts independent of sex, education, and age.
AB - BACKGROUND: Incidence rates of dementia appear to be declining in high-income countries according to several large epidemiological studies. We aimed to describe declining incident dementia rates across successive birth cohorts in a U.S. population-based sample and to explore the influences of sex and education on these trends. METHODS: We pooled data from two community-sampled prospective cohort studies with similar study aims and contiguous sampling regions: the Monongahela Valley Independent Elders Survey (1987-2001) and the Monongahela-Youghiogheny Healthy Aging Team (2006-Ongoing). We identified four decade-long birth cohorts spanning birth years 1902-1941. In an analysis sample of 3,010 participants (61% women, mean baseline age = 75.7 years, mean follow-up = 7.1 years), we identified 257 cases of incident dementia indicated by a Clinical Dementia Rating of 1.0 or higher. We used Poisson regression to model incident dementia rates by birth cohort, age, sex, education, and interactions of Sex × Cohort and Sex × Education. We further examined whether cohort effects varied by education, testing a Cohort × Education interaction and stratifying the models by education. RESULTS: Compared to the earliest birth cohort (1902-1911), each subsequent cohort had a significantly lower incident dementia rate (1912-1921: incidence rate ratio [IRR] = 0.655, 95% confidence interval [95% CI] = 0.477-0.899; 1922-1931: IRR = 0.387, 95% CI = 0.265-0.564; 1932-1941: IRR = 0.233, 95% CI = 0.121-0.449). We observed no significant interactions of either sex or education with birth cohort. CONCLUSIONS: A decline in incident dementia rates was observed across successive birth cohorts independent of sex, education, and age.
KW - Cognition
KW - Cognitive aging
KW - Community-based
KW - Epidemiology
UR - http://www.scopus.com/inward/record.url?scp=85068481902&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85068481902&partnerID=8YFLogxK
U2 - 10.1093/gerona/gly236
DO - 10.1093/gerona/gly236
M3 - Article
C2 - 30312371
AN - SCOPUS:85068481902
VL - 74
SP - 1439
EP - 1445
JO - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
JF - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
SN - 1079-5006
IS - 9
ER -