The Genetic Liability to Disability Retirement: A 30-Year Follow-Up Study of 24,000 Finnish Twins

Peer reviewe

Associations of CAIDE Dementia Risk Score with MRI, PIB-PET measures, and cognition

Background: CAIDE Dementia Risk Score is the first validated tool for estimating dementia risk based on a midlife risk profile. Objectives: This observational study investigated longitudinal associations of CAIDE Dementia Risk Score with brain MRI, amyloid burden evaluated with PIB-PET, and detailed cognition measures. Methods: FINGER participants were at-risk elderly without dementia. CAIDE Risk Score was calculated using data from previous national surveys (mean age 52.4 years). In connection to baseline FINGER visit (on average 17.6 years later, mean age 70.1 years), 132 participants underwent MRI scans, and 48 underwent PIB-PET scans. All 1,260 participants were cognitively assessed (Neuropsychological Test Battery, NTB). Neuroimaging assessments included brain cortical thickness and volumes (Freesurfer 5.0.3), visually rated medial temporal atrophy (MTA), white matter lesions (WML), and amyloid accumulation. Results: Higher CAIDE Dementia Risk Score was related to more pronounced deep WML (OR 1.22, 95% CI 1.05-1.43), lower total gray matter (beta- coefficient -0.29, p = 0.001) and hippocampal volume (beta- coefficient -0.28, p = 0.003), lower cortical thickness (beta-coefficient -0.19, p = 0.042), and poorer cognition (beta-coefficients -0.31 for total NTB score, -0.25 for executive functioning, -0.33 for processing speed, and -0.20 for memory, all p <0.001). Higher CAIDE Dementia Risk Score including APOE genotype was additionally related to more pronounced MTA (OR 1.15,95% CI 1.00-1.30). No associations were found with periventricular WML or amyloid accumulation. Conclusions: The CAIDE Dementia Risk Score was related to indicators of cerebrovascular changes and neurodegeneration on MRI, and cognition. The lack of association with brain amyloid accumulation needs to be verified in studies with larger sample sizes.Peer reviewe

Occupational complexity and cognition in the FINGER multidomain intervention trial

Introduction Lifetime exposure to occupational complexity is linked to late-life cognition, and may affect benefits of preventive interventions. Methods In the 2-year multidomain Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER), we investigated, through post hoc analyses (N = 1026), the association of occupational complexity with cognition. Occupational complexity with data, people, and substantive complexity were classified through the Dictionary of Occupational Titles. Results Higher levels of occupational complexity were associated with better baseline cognition. Measures of occupational complexity had no association with intervention effects on cognition, except for occupational complexity with data, which was associated with the degree of intervention-related gains for executive function. Discussion In older adults at increased risk for dementia, higher occupational complexity is associated with better cognition. The cognitive benefit of the FINGER intervention did not vary significantly among participants with different levels of occupational complexity. These exploratory findings require further testing in larger studies.Peer reviewe

Recruitment and Baseline Characteristics of Participants in the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER)-A Randomized Controlled Lifestyle Trial

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Heritability of lumbar flexibility and the role of disc degeneration and body weight

Spinal range of motion is evaluated in assessing patients with back problems and monitoring outcomes, as well as in general fitness assessments. Yet, determinants of the substantial interindividual variation in spinal range of motion are not well understood. Substantial genetic effects on global measures of range of motion and hypermobility have been suggested from earlier studies, but genetic influences specifically on spinal range of motion have not been previously studied. The objectives of the present study were to investigate the relative role of genetic and environmental influences on lumbar range of motion in adult men and the pathways through which genes may influence range of motion. Thus we conducted a classic twin study of 300 monozygotic and dizygotic male twin pairs with consideration of covariates, using standard statistical methods. All subjects underwent a clinical examination, including general anthropometrics, lumbar range of motion, and lumbar MRI to assess disc degeneration, as well as an extensive interview on environmental and behavioral exposures and back pain history. We found the proportion of variance in lumbar range of motion attributable to genetic influences (heritability estimate) to be 47%. The extent of lumbar range of motion in flexion was predominantly determined by genetic influences (64%), while extension was influenced to a somewhat greater degree by environmental and behavioral factors. Statistically significant age-adjusted genetic correlations were found between lumbar extension and disc degeneration variables (ra = –0.38 to –0.43) and between flexion and body weight (ra = –0.33), suggesting two pathways through which genes influence lumbar range of motio