Johan Skoog

A Longitudinal Study of the Mini-Mental State Examination in Late Nonagenarians and Its Relationship with Dementia, Mortality, and Education

To examine level of and change in cognitive status using the Mini‐Mental State Examination (MMSE) in relation to dementia, mortality, education, and sex in late nonagenarians.

Better Cognition in New Birth Cohorts of 70 Year Olds, But Greater Decline Thereafter

Objectives To evaluate birth cohort differences in level of cognition and rate of change in old age. Methods Data were drawn from three population-based Swedish samples including age-homogenous cohorts born 1901/02, 1906/07, and 1930, and measured on the same cognitive tests at ages 70, 75, and 79 as part of the Gerontological and Geriatric Populations Studies in Gothenburg (H70). We fitted growth curve models to the data using a Bayesian framework and derived estimates and inferences from the marginal posterior distributions. Results We found moderate to large birth cohort effects in level of performance on all cognitive outcomes. Later born cohorts, however, showed steeper linear rate of decline on reasoning, spatial ability, and perceptual- and motor-speed, but not on picture recognition memory and verbal ability. Discussion These findings provide strong evidence for substantial birth cohort effects in cognition in older ages and emphasize the importance of life long environmental factors in shaping cognitive aging trajectories. Inferences from cognitive testing, and standardization of test scores, in elderly populations must take into account the substantial birth cohort differences.

Sleep disturbances and dementia risk: A multicenter study

Few longitudinal studies assessed whether sleep disturbances are associated with dementia risk.

Do later-born birth cohorts of septuagenarians sleep better? A prospective population-based study of two birth cohorts of 70-year-olds

Study Objectives To investigate birth cohort differences in the prevalence of insomnia from ages 70 to 79. Methods Data were drawn from population-based samples of two cohorts of septuagenarians; the early-born 1901-07-cohort, who took part in psychiatric examinations between 1971 and 1986 (n = 681), and the later-born 1930-cohort examined between 2000 and 2010 (n = 943). Examinations were conducted at ages 70, 75, and 79. Criteria for insomnia were identical across cohorts and included sleep dissatisfaction accompanied with complaints of difficulty initiating or maintaining sleep. Associations were analyzed with logistic growth curve models. Results The later-born cohort had lower odds for insomnia at age 70 (OR = 0.52, 95% CI: 0.32-0.87) compared with the earlier born cohort. Age was not related to insomnia as a main effect but we found an interaction between age and birth cohort (OR = 1.14, 95% CI: 1.08-1.21); insomnia increased with age in the later but not in the early-born cohort. Women had higher odds for insomnia compared with men (OR = 3.10, 95% CI: 2.02-4.74), and there was an interaction between sex and birth cohort (OR = 0.51, 95% CI: 0.30-0.88; there were larger cohort differences among women than among men and less sex differences in the later than in the earlier born cohort. Also, there were no significant differences between the cohorts in taking sleep medications. Conclusions Our findings provide evidence of improved self-reported sleep in later-born cohorts of septuagenarians, but the difference diminished with age. The prevalence of self-reported insomnia was greater in women than in men, but sex differences were less pronounced in the later-born cohort.

FACTORS AND TRANSITIONS BETWEEN COGNITIVE STATES: A MULTI-STUDY APPROACH USING DATA FROM SIX INTERNATIONAL LONGITUDINAL STUDIES OF AGEING

antipsychotic in the past year. Cholinesterase inhibitors, memantine, and combination therapies contributed to 87%, 13%, and <1% of prescription initiations, respectively. No differences were seen in choice of initial treatment strategy by sex. Initiation with memantine was higher among patients with vascular dementia and older age at diagnosis, and calendar time (Figure 1). Median time from diagnosis to treatment initiation was 0.3 years (interquartile range 0.1, 0.8) and was similar among the 3 cholinesterase inhibitors and memantine, but was longer for combination therapy. Conclusions:This study was the first to evaluateMND treatment patterns by sex and MND subtype and to our knowledge, is the largest MND drug utilization study to date.With a total follow-up period of up to 20 years that covers the entire period that these MND drugs have been available, this study characterized their use in a realworld setting.

Transitions across cognitive states and death among older adults in relation to education: A multistate survival model using data from six longitudinal studies

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.

TRANSITIONS ACROSS COGNITIVE STATES AND MORTALITY AMONG OLDER ADULTS: A MULTI-STATE SURVIVAL MODEL

that assume the trajectory form is the same for everyone in the sample. Including demographic variables as covariates in such studies only allows for the identification of mean differences. In contrast, we used structural equation model (SEM) trees to identify heterogenous subgroups that demonstrate differential trajectories of change in cognition. SEM Trees partitions the dataset into subsets (groups of participants) based on the splitting of covariates, with a latent change growth model fit to each resultant subset. Methods:9 waves from the representative samples of the Health and Retirement Study and Assets and Health Dynamics of the Oldest Old (N1⁄4 20,685), were analyzed. Covariates were years of education, race (white, black, other), Hispanic, and gender. Each identified subset was fit with SEM models on mental status scores. Results: Different trajectories were observed with covariate splits on race, Hispanic ethnicity, and education combinations. The figure shows that formental status,Whitewith 14 years of education,White, 12-13 years, and Nonwhite, 16 years had highest intercept scores, with age declines after the mid-70’s. Nonwhite andHispanics with 12-15 years andWhite, 9-11 years formed themiddle groups for intercepts, showing declines in the late 60’s. Nonwhites 11 years, and whites 6 years had the lowest intercepts and declines just after age 60. Conclusions:SEM trees indicated different patterns of cognitive aging in a population sample. These findings suggest that cognitive disparities are rooted not only by race or ethnicity but education, and that whites are more protected from cognitive decline than nonwhites even with only a few years of high school. We conclude with a discussion of the importance of examining not just mean effects, but also allowing the change parameters to vary, and by allowing interactions between covariates.

A POPULATION-BASED STUDY ON THE RELATION BETWEEN SLEEP DISTURBANCE AND BETA-AMYLOID 42 IN CEREBROSPINAL FLUID IN 70-YEAR-OLDS

risks were allowed to depend on age (5-year age groups), APOE-ε4, and early-life intellectual factors including educational attainment, academic performance in high school (first-year English, algebra, or geometry), and written language skills (idea density, grammatical complexity). Results: Each five-year increase in age was associated with a reduced chance of reversion to normal cognition, but this reached significance only for those 90-95 years (90-95 vs. 75-80 age groups: hazard ratio [HR]1⁄40.37; 95% confidence interval [CI]1⁄40.19-0.74). In transition models including age, APOE and education, APOE-ε4 carriers (1+ alleles) had a significantly lower chance of reversion than noncarriers (HR1⁄40.37; 95% CI1⁄40.22-0.62), whereas more highly educated participants had a significantly higher chance of reversion (Masters degree or higher vs. high school or lower: HR1⁄42.43; 95% CI1⁄41.13-5.20). Participants with higher academic performance in English (>1⁄490% vs <90%: HR1⁄41.58; 95% CI1⁄41.09-2.30) and higher idea density (Quartile [Q] 3-4 vs Q1-2: HR1⁄42.39; 95% CI1⁄41.39-4.10) or grammatical complexity (Q2-4 vs Q1: HR1⁄43.55; 95% CI1⁄41.08-11.69) had significantly higher chances of reversion in models adjusted for age, APOE and education. Conclusions:Although a diagnosis of mild cognitive impairment has been associated with an increased risk of progressing to dementia, indicators of cognitive resilience may predict reversion from this state to normal cognition. Predictors of these reverse transitions could inform strategies to prevent or postpone transitions to cognitive impairment and dementia.