Piccinin et al., 2013. Coordinated analysis of age, sex, and education effects on change in MMSE scores

Piccinin, A. M., Muniz-Terrera, G., Clouston, S., Reynolds, C. A., Thorvaldsson, V., Deary, I. J., Deeg, DJ, Johansson, B., Mackinnon, A., Spiro, A., & Starr, J. M. (2012). Coordinated analysis of age, sex, and education effects on change in MMSE scores. Journals of Gerontology Series B: Psychological Sciences and Social Sciences, 68(3), 374-390.

Year: 
2013
Status: 
complete
Abstract: 

Objectives. We describe and compare the expected performance trajectories of older adults on the Mini-Mental Status Examination (MMSE) across six independent studies from four countries in the context of a collaborative network of longitudinal studies of aging. A coordinated analysis approach is used to compare patterns of change conditional on sample composition differences related to age, sex, and education. Such coordination accelerates evaluation of particular hypotheses. In particular, we focus on the effect of educational attainment on cognitive decline.

Method. Regular and Tobit mixed models were fit to MMSE scores from each study separately. The effects of age, sex, and education were examined based on more than one centering point.

Results. Findings were relatively consistent across studies. On average, MMSE scores were lower for older individuals and declined over time. Education predicted MMSE score, but, with two exceptions, was not associated with decline in MMSE over time.

Conclusion. A straightforward association between educational attainment and rate of cognitive decline was not supported. Thoughtful consideration is needed when synthesizing evidence across studies, as methodologies adopted and sample characteristics, such as educational attainment, invariably differ.

Muniz-Terrera et al., 2012. Investigating terminal decline: results from a UK population-based study of aging.

Muniz-Terrera, G., van den Hout, A., Piccinin, A. M., Matthews, F. E., & Hofer, S. M. (2013). Investigating terminal decline: Results from a UK population-based study of aging. Psychology and aging, 28(2), 377.

Year: 
2012
Status: 
complete
Abstract: 

The terminal decline hypothesis states that in the proximity of death, an individual’s decline in cognitive abilities accelerates. We aimed at estimating the onset of faster rate of decline in global cognition using Mini Mental State Examination (MMSE) scores from participants of the Cambridge City over 75 Cohort Study (CC75C), a U.K. population-based longitudinal study of aging where almost all participants have died. The random change point model fitted to MMSE scores structured as a function of distance to death allowed us to identify a potentially different onset of change in rate of decline before death for each individual in the sample. Differences in rate of change before and after the onset of change in rate of decline by sociodemographic variables were investigated. On average, the onset of a faster rate of change occurred about 7.7 years before death and varied across individuals. Our results show that most individuals experience a period of slight decline followed by a much sharper decline. Education, age at death, and cognitive impairment at study entry were identified as modifiers of rate of change before and after change in rate of decline. Gender differences were found in rate of decline in the final stages of life. Our study suggests that terminal decline is a heterogeneous process, with its onset varying between individuals. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Cadar et al., 2016. The role of cognitive reserve on terminal decline: a cross-cohort analysis from two European studies

Cadar, D., Stephan, B. C., Jagger, C., Johansson, B., Hofer, S. M., Piccinin, A. M., & Muniz‐Terrera, G. (2016). The role of cognitive reserve on terminal decline: A cross‐cohort analysis from two European studies: OCTO‐Twin, Sweden, and Newcastle 85+, UK. International Journal of Geriatric Psychiatry, 31(6), 601-610.

Year: 
2017
Status: 
complete
Abstract: 

OBJECTIVE: Cognitive performance shows a marked deterioration in close proximity to death, as postulated by the terminal decline hypothesis. The effect of education on the rate of terminal decline in the oldest people (i.e. persons 85+ years) has been controversial and not entirely understood. In the current study, we investigated the rate of decline prior to death with a special focus on the role of education and socioeconomic position, in two European longitudinal studies of ageing: the Origins of Variance in the Old-Old: Octogenarian Twins (OCTO-Twin) and the Newcastle 85+ study.

METHODS: A process-based approach was used in which individuals' cognitive scores were aligned according to distance to death. In a coordinated analysis, multilevel models were employed to examine associations between different markers of cognitive reserve (education and socioeconomic position) and terminal decline using the mini-mental state examination (MMSE), controlling for age at baseline, sex, dementia incidence and time to death from the study entry to the time of death within each cohort.

RESULTS: The current findings suggest that education was positively associated with higher MMSE scores prior to death in the OCTO-Twin, but not in the Newcastle 85+ study, independent of socioeconomic position and other factors such as baseline age, sex and time to death from the study entry. However, education was not associated with the rate of terminal decline in both of these studies.

CONCLUSIONS: Our results offer only partial support to the cognitive reserve hypothesis and cognitive performance prior to death.

Robitaille et al., 2018. Transitions across cognitive states and death among older adults in relation to education: a multi-state survival model using data from six longitudinal studies.

Robitaille, A., van den Hout, A., Machado, R.M., Bennett, D.A., Čukić, I., Deary, I.J., Hofer, S.M., Hoogendijk, E.O., Huisman, M., Johansson, B., Koval, A.V., van der Noordt, M., Piccinin, A.M., Rijnhart, J.J.M., Singh-Manoux, A., Skoog, J., Skoog, I., Starr, J., Vermunt, L., Clouston, S., Muniz-Terrera, G. (2018). Transitions across cognitive states and death among older adults in relation to education: a multi-state survival model using data from six longitudinal studies. Alzheimer's & Dementia, 14(4), 462-472. DOI: 10.1016/j.jalz.2017.10.003

Year: 
2018
Status: 
complete
Presentation Citations: 

Robitaille, A., Van den Hout A., Machado, R.J.M., Čukić, I., Deary, I.J., Hofer, S.M., Hoogendijke, E.O., Johansson, B., Koval, A.V., Van der Noordt, M., Piccinin, A.M., Rijnhart, J.J.M., Singh-Manoux, A., Skoog, J., Skoog, I., Vermunt, L., Muniz-Terrera, G. (2017, July). Transitions across Cognitive States and Mortality among Older Adults: A Multi-State Survival Model. Paper presented at the Alzheimer's Association International Conference (AAIC), London, UK.  

Hoogendijke, E.O., Robitaille, A., Van den Hout A., Machado, R.J.M., Čukić, I., Hofer, S.M., Johansson, B., Koval, A.V., Van der Noordt, M., Rijnhart, J.J.M., A., Skoog, J., Vermunt, L., Muniz-Terrera, G. (May, 2017). Transitions across cognitive states and mortality among older adults in relation to education. A multistate survival model using data from six longitudinal studies. Paper presented at the 29th REVES meeting, Santiago de Chile, Chile.

Abstract: 

Introduction: This study examines the role of educational attainment, an indicator of cognitive reserve, on transitions in later life between cognitive states (normal Mini-Mental State Examination (MMSE), mild MMSE impairment, and severe MMSE impairment) and death. Methods: Analysis of six international longitudinal studies was performed using a coordinated approach. Multistate survival models were used to estimate the transition patterns via different cognitive states. Life expectancies were estimated. Results: Across most studies, a higher level of education was associated with a lower risk of transitioning from normal MMSE to mild MMSE impairment but was not associated with other transitions. Those with higher levels of education and socioeconomic status had longer nonimpaired life expectancies. Discussion: This study highlights the importance of education in later life and that early life experiences can delay later compromised cognitive health. This study also demonstrates the feasibility and benefit in conducting coordinated analysis across multiple studies to validate findings.

Van den Kommer et al., 2010. Classification models for early identification of persons at risk for dementia in primary care: An evaluation in a sample aged 80 years and older

Van den Kommer, T. N., Bontempo, D. E., Comijs, H. C., Hofer, S. M., Dik, M. G., Piccinin, A. M., Jonker, C., Deeg, D. J. H., & Johansson, B. (2010). Classification models for early identification of persons at risk for dementia in primary care: An evaluation in a sample aged 80 years and older, Dementia and Geriatric Cognitive Disorders, 28(6), 567-577.

Year: 
2010
Status: 
complete
Abstract: 

Aim: To evaluate previously developed classification models to make implementation in primary care possible and aid early identification of persons at risk for dementia. Methods: Data were drawn from the OCTO-Twin study. At baseline, 521 persons ≧80 years of age were nondemented, and for 387 a blood sample was available. Predictors of dementia were collected and analyzed in initially nondemented persons using generalized estimating equations and Cox survival analyses. Results: In the basic model using predictors already known or easily obtained (basic set), the mean 2-year predictive value increased from 6.9 to 28.8% in persons with memory complaints and an MMSE score ≤25. In the extended model, using both the basic set and an extended set of predictors requiring further assessment, the 8-year predictive value increased from 15.0 to 45.8% in persons with low cholesterol and an MMSE score ≤24. Conclusion: Both models can contribute to an improved early identification of persons at risk for dementia in primary care.

Clouston et al., 2014. The Dynamic Relationship Between Physical Function and Cognition in Longitudinal Aging Cohorts

Clouston, S., Brewster, P., Kuh, D., Richards, M., Cooper, R., Hardy, R., Rubin, M., & Hofer, S. M. (2013). The dynamic relationship between physical function and cognition in longitudinal aging cohorts: A systematic review. Epidemiologic Reviews. Published online 2013 January 24.  doi: 10.1093/epirev/mxs004.

Year: 
2013
Status: 
complete
Abstract: 

On average, older people remember less and walk more slowly than do younger persons. Some researchers argue that this is due in part to a common biologic process underlying age-related declines in both physical and cognitive functioning. Only recently have longitudinal data become available for analyzing this claim. We conducted a systematic review of English-language research published between 2000 and 2011 to evaluate the relations between rates of change in physical and cognitive functioning in older cohorts. Physical functioning was assessed using objective measures: walking speed, grip strength, chair rise time, flamingo stand time, and summary measures of physical functioning. Cognition was measured using mental state examinations, fluid cognition, and diagnosis of impairment. Results depended on measurement type: Change in grip strength was more strongly correlated with mental state, while change in walking speed was more strongly correlated with change in fluid cognition. Examining physical and cognitive functioning can help clinicians and researchers to better identify individuals and groups that are aging differently and at different rates. In future research, investigators should consider the importance of identifying different patterns and rates of decline, examine relations between more diverse types of measures, and analyze the order in which age-related declines occur.

Piccinin et al, 2006. Cross-national IALSA coordinated analysis of age, sex, and education effects on change in MMSE scores.

Year: 
2006
Status: 
complete
Presentation Citations: 

Piccinin, A. M., Hofer, S. M., Anstey, K. J., Deary, I. J., Deeg, D. J. H., Johansson, B., Mackinnon, A. J., Spiro, A., & Thorvaldsson, V. (2006, November). Cross-national IALSA coordinated analysis of age, sex, and education effects on change in MMSE scores. In S. M. Hofer & A. M. Piccinin (Chairs), Integrative Analysis of Longitudinal Studies on Aging: Accounting for Health in Aging-Related Processes. Paper symposium conducted at the annual Gerontological Society of America Conference, Dallas, TX.

Comijs et al., 2009. Classification models for early identification of persons at risk for dementia, a replication study.

Year: 
2009
Status: 
complete
Presentation Citations: 

Comijs, H. Van Den Kommer, T. N., Bontempo, D. E., Hofer, S. M., Dik, M., Piccinin, A. M., Deeg, D. J., & Johansson, B. (2009, November). Classification models for early identification of persons at risk for dementia, a replication study.  In S. M. Hofer (Chair), Coordinated and pooled data analyses of longitudinal studies of aging: Aging and dementia-related change in cognition, affect, and physical functioning. Paper symposium conducted at the annual meeting of the Gerontological Society of America, Atlanta.

Abstract: 

Background: The goal of the present study is to develop a classification model for use in primary care using markers which are relatively easy to determine to aid early identification of persons at risk for dementia. 

Methods: Data were used from the Origins of Variance in the Old-Old (OCTO-Twin) study. The baseline sample included 521 non-demented subjects aged 80 and older. Relevant predictors on dementia were collected two years prior to dementia diagnosis. Dementia diagnosis was based on DSM-III-R criteria. Data were analyzed using generalized estimating equations and Cox survival analyses. 

Results: Overall, the two-year incidence of dementia was 6.9%. Reporting memory complaints was the strongest predictor of dementia. Memory complaints and a MMSE score ≤ 25 resulted in a predictive value for dementia of 28.8%. No memory complaints, drinking no alcohol and a MMSE score ≤ 24 resulted in a predictive value of 18.0%. Reporting no memory complaints, drinking alcohol, having functional limitations and a MMSE score ≤ 24 resulted in a percentage of 24.7% identified with dementia after two years of follow-up. 

Conclusions: The developed classification tree could contribute to early identification of persons at risk for dementia in primary care in a feasible and cost-effective way.