OCTO Twin Origins of Variance in the Old-Old General presentation Boo Johansson National Institute on Aging: AG Life span

Friday Harbor Psychometrics Workshop 2010 Acknowledgements Funded in part by Grant R13AG A1 from the National Institute on Aging The views expressed in written conference materials or publications and by speakers and moderators do not necessarily reflect the official policies of the Department of Health and Human Services; nor does mention by trade names, commercial practices, or organizations imply endorsement by the U.S. Government.

Major Swedish Longitudinal Aging Studies..at that time - population-based - longitudinal design - possible to conduct - informative H70 (70+), OCTO (84+), …. SATSA (55+) ….??

Background for the OCTO Twin Study - Observations of substantial individual differences in rate and patterns of aging - Understanding the origins of this variability is of fundamental importance – What are the relative contributions of genetic and environmental influences? - Limited information about the oldest old age segement in the above respect 1988

The planning for a Twin Study of the Old-Old (80 +) started ~ 20 years ago (1988) H70,OCTO, SATSA..the missing ‘piece’ OCTO Twin

OCTO Twin - OVERALL AIM To estimate the relative contributions of environmental and genetic influences to the variability in health and biobehavioral functioning ….. at each measurement occasion as well as to longitudinal change and continuity during inter- occasion intervals

..in a life span genetic and environmental influence perspective

An individual difference approach focus on variance among individuals within a population Directs our attention to the origins of variability within an age group Thus, we become compelled to search for the fundamental sources for observed differences in a specific phenotype

The prototypic twin design Monozygotic (MZ) pairs and Dizygotic (like-sex) pairs compared with respect to intra-pair similarities

MZ - monozygotic twins share 100% of all genetic influences

Same birthday Same parents DZ - dizygotic twins share on average 50% of genetic influences

Wave 1 Wave 2Wave 3 Wave 4 Wave  1993  1995  1997  1999 MarchMayAprilMarchMarch  1994  1996  1998  2000  2002 MarchMarchMarchMarchMarch The OCTO Twin Design 5 measurement occasions, 2-years apart

Domains at focus Health and functional capacity Cognitive functioning Personality and personal control Psychological well-being Interpersonal functioning Using largely the same measures as in reference studies (H70, OCTO, SATSA

Health and functional capacity - Self-rated health - Self-reported medical history (”checklist”) - Sensory (Vision, hearing) - PB, Pulse, BMI - Functional tests of balance and gait - Grip strength, lung capacity - Contacts with the health care system (district nurse, physicans, and hospital) - Information from medical (ICD-10 coded) and dental records - Medications (ATC –codes) - Blood chemistry panel

Memory and Cognition - Cog.status – MMSE, Clock Test, Coin Test - Inductive reasoning – figure logic - Psychomotor speed - Psif, Digit-Symbol - Visuospatial ability – Koh’s Block - Primary memory – Digit Span - Semantic memory – Synonyms - Information - Episodic memory – Prose, MIR, Thurstone Picture memory

Dementia work-up individuals suspected for dementia - Review of memory and cognitive tests - Informant neuropsychological interview - Review of medical records and supplement information - A consensus diagnosis conference (DSM, ICD, NINCDS-ADRA, NINDS-AIREN, etc)

Personality and Personal Control - Eysenck Personality Inventory (EPI) - Global Locus of Control - Heatlh Locus of Control

Psychological Well-being - Life Satisfaction Scale (LSI-Z) - Depressive symptoms scale (CES-D) - Open ended questions, e.g. significant life events

Interpersonal functioning - Social networks - Contact frequencies - Confidants - Loneliness

Functional capacity - ADL Apparatus Test - ADL and IADL Scales (Self and RN ratings) - Need for help in ADL/IADL - Home help/institutional care - Technical aids, mobility, hearing, vision

Testing sessionTesting session

Supplement information Twin Registry Ratings by RNs’ and PD Medical records Dental records Death certificates Dementia work-up Autopsy/neuropathology

Procedure - In-person/individual examinations in place of residence across the country - by trained and supervised RNs - using a broad-based biobehavioral battery Members of a twin pair never investigated by same RN to avoid expectation bias. The RNs’ blind to zygosity.

The OCTO Twin Sample Twins in complete pairs, 80 years and older at baseline (< 1913) MZ (monozygotic) twin pairs (N=149) and same- sex DZ (dizygotic) twin pairs (N=202) All survivors followed longitudinally across 5 waves, 2-years apart

Population selection in OCTO Twin: Number of tested individuals and pairs across waves (8y) W1 W2W3W4W5 MZ DZMZ DZMZ DZMZ DZMZ DZ Pairs Men Women Total MZ %42,541,745,150,046,5 Individuals Men Women Total702 (704) MZ %42,541,441,445,142,5 R-rate > 90%

SATSA OCTO Twin Gender Harmony Ongoing Swedish Twin Studies on Aging

Boo Johansson