Oregon Brain Aging Study
The Oregon Brain Aging Study aims to:
- Determine if there are individuals especially resistant to brain aging as evidenced by a long cognitive heath span (CHS)
- Identify circumscribed quantitative aging phenotypes that best predict CHS
- Establish which neuropathologic signs of brain aging best explain changes in the quantitative phenotypes associated with CHS.
Overview
- Acronym
- OBAS
- Contacts
-
General Design
- Study design
- Cohort
- Start - End Year
- 1989 -
- General Information on Follow Up (profile, frequency)
-
Full protocol administered in person annually. Shorter protocol administered at 6 months intervals between annual exams (administered in person until 2006, then changed to telephone follow-up)
- Recruitment Target
-
- Individuals
- Number of Participants
- 305
- Number of Participants with Biological Samples
- 297
- Supplementary Information
-
The Oregon Brain Aging Study (OBAS) was initiated in 1989 at the NIA/Layton Oregon Aging and Alzheimer’s Disease Center consisting of community-dwelling, functionally independent adults aged 55 years and older. Between 1989 and 2005, 376 subjects were evaluated, and 305 subjects met inclusion criteria and were enrolled. 293 of the 305 subjects were 65 years of age or older. Initial entry criteria required subjects to be free of most co-morbid illnesses. In order to include subjects who were more representative of the general population, entry criteria was modified in 2004 to include subjects with well-controlled, chronic medical conditions common with advanced age, such as hypertension and coronary artery disease. Attrition rates caused by loss to follow-up other than death were less than 1% per year.
Access
Availability of data and biosamples
| Possible Access to Data | |
| Possible Access to Biosamples | |
| Other |
|
MRI volumetrics, Neuropathologic findings, APOE. Request OBAS data from the OHSU Layton Center:
https://www.ohsu.edu/xd/health/services/brain/getting-treatment/diagnosis/alzheimers-aging-dementia/research/for-researchers/clinical-data-resources.cfm
Marker Paper
Howieson DB, Holm LA, Kaye JA, Oken BS, Howieson J. Neurologic function in the optimally healthy oldest old. Neuropsychological evaluation. Neurology 1993;43:1882-1886
PUBMED 8413942Supplementary Information
Kaye JA, Oken BS, Howieson DB, Howieson J, Holm LA, Dennison K. Neurologic evaluation of the optimally healthy oldest old. Archives of Neurology 1994;51:1205-1211. PMID: 7986175.
Silbert LC, Dodge HH, Perkins LG, Sherbakov L, Lahna D, Erten-Lyons D, Woltjer R, Shinto L, Kaye JA. Trajectory of white matter hyperintensity burden preceding mild cognitive impairment. Neurology 79:741-747, 2012.PMC3421153.
Dodge HH, Zitzelberger T, Oken BS, Howieson D, Kaye J. A randomized placebo-controlled trial of ginkgo biloba for the prevention of cognitive decline. Neurology 70:1809-1817, 2008. PMC2639649.
Timeline
Populations
OBAS I
Selection Criteria
- Minimum age
-
55
- Countries
-
- United States of America
- Territory
-
Portland, OR metro area.
- Ethnic Origin
-
- The participants are primarily Caucasian. One participant is Asian and another one is Native American.
- Health Status
-
- Free of most co-morbid illnesses
- Other Criteria
-
Inclusion Criteria:
- Principal language, English
- Functionally independent
- Has not sought evaluation for cognitive impairment
- Willing and able to return for follow-up
- Does not refuse to undergo post mortem examination
- Score of < =12 on Instrumental Activities of Daily Living Scale (OARS)
- Score of > =24 on Mini Mental State Exam
- Score of <=10 on Cornell Depression Scale
- Score of <= 11 on Geriatric Depression Scale
- Score of 0 on Clinical Dementia Rating Scale
- Gives informed consent
- No exclusion criteria listed in below.
Exclusion criteria:Medical Conditions- Diabetes mellitus
- Hypertension (supine BP > 160/95)
- Angina pectoris or myocardial infarction
- Cardiac arrhythmia
- Coronary bypass/carotid endarterectomy
- Stroke or TIA
- Parkinson disease
- Chronic pulmonary disease
- Chronic renal disease
- Chronic immunosuppression
- Vitamin deficiencies
- Seizure disorder
- Active cancer (< 5 years without recurrence)
- Hypothyroidism)
Psychiatric Disorders- Chronic schizophrenia
- Major affective disorders
- Chronic anxiety or phobias
Vision and Hearing- Vision uncorrectable to 20/100 O.U.(near card)
- Hearing loss (interferes with speech perception)
Other Conditions- Alcohol abuse / drug abuse
- Significant head injury (>30 min unconscious)
- Unexplained prolonged loss of consciousness
- Use of medicines impairing cognitive function
- Internal metal such as pacemakers, will be excluded from MR imaging
Sources of Recruitment
- General Population
-
- Volunteer enrolment
Sample Size
- Number of Participants
- 216
- Number of Participants with Biological Samples
- 209
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | OBAS - Study I - Evaluation OBAS I |
|
|
1989 (March) | 2013 (December) |
OBAS II
Selection Criteria
- Minimum age
-
85
- Countries
-
- United States of America
- Territory
-
Portland, OR metro area.
- Ethnic Origin
-
- The participants are primarily Caucasian. Two participants are Asian and one participant is Native American.
- Health Status
-
- Well-controlled, chronic medical conditions common with advanced age, such as hypertension and coronary artery disease are acceptable.
- Other Criteria
-
Inclusion Criteria:
- Age > 84 years
- No subjective complaint of memory impairment compared to others of their own age
- Has not sought assessment for memory or cognitive dysfunction
- Normal memory function defined by an education-adjusted score on the Logical Memory Subscale of the Wechsler Memory Scale-Revised: >8 for 16 or more years of education; > or = 4 for 8-15 years of education; >2 for 0 -7 years of education
- Mini-Mental State Examination score >23
- Blessed Orientation Memory Concentration Test (Telephone Screen) <12
- Functionally independent (ADL= 0)
- Clinical Dementia Rating = 0
- Absence of significant depressive symptoms: CES-D-10 score < 4
- Sufficient vision and hearing to complete all testing
- Sufficient English language skills to complete all testing
- General health status that will not interfere with ability to complete longitudinal study (conditions that will likely lead to this problem are listed below in the study exclusions list)
- Informant available with frequent (at least 1 hour per day 3 days a week) contact with subject to verify functional status.
Exclusion criteria:- Diseases associated with dementia such as Alzheimer disease, ischemic vascular dementia, normal pressure hydrocephalus, or Parkinson disease
- Significant disease of the CNS such as brain tumor, seizure disorder, subdural hematoma, cranial arteritis
- Current (within the last 2 years) alcohol or substance abuse according to DSM-IV criteria
- Major depression, schizophrenia, or other major psychiatric disorder defined by DSM-IV criteria
- Abnormal laboratory values indicating B12 deficiency, thyroid disease, or urinary tract infection (documented chronic bacterial colonization is acceptable)
- Unstable or significantly symptomatic cardiovascular disease such as coronary artery disease with frequent angina, or congestive heart failure with shortness of breath at rest
- Insulin dependent diabetes mellitus
- Active systemic cancer within 5 years of study entry (Gleason Grade <3 prostate cancer, and non-metastatic skin cancers are acceptable)
- Illness that requires >1 visit per month to a clinician
- Progressive vision loss (age-related macular degeneration already beginning to significantly degrade vision)
- Need for oxygen supplementation for adequate function
- Medications: Frequent use of high doses of analgesics; Sedative medications except for those used occasionally for sleep (use limited to no more than twice per week);
- Subjects taking CNS-active medications that have not been on stable doses for at least 2 months including cimetidine, beta-blockers, and selective serotonin reuptake inhibitors; Subjects taking neuroleptics, antiparkinsonian agents, systemic corticosteroids, and narcotic analgesics; in the case where these were used for a self-limited time they must have been discontinued for a period of five half-lives prior to baseline; Subjects will not be excluded if they are taking other over-the counter supplements, but the dose must not be changed during the course of the trial unless medically indicated; the presence and dose of these agents will be recorded; Subjects taking cholinesterase inhibitors; Use of investigational drugs within five half-lives prior to baseline.
Sources of Recruitment
- Participants from Existing Studies
-
- Dementia Prevention Study
- Supplementary Information
-
Those still alive, willing to participate and not demented, transitioned from an earlier study into OBAS II when that study ended (Dementia Prevention Study – DPS; Dodge HH, Zitzelberger T, Oken BS, Howieson D, Kaye J. A randomized placebo-controlled trial of ginkgo biloba for the prevention of cognitive decline. Neurology 70:1809-1817, 2008. PMC2639649).
The original DPS participants were recruited primarily through mass mailings to age-eligible individuals in the greater Portland area. Mailing lists were obtained from the Oregon Department of Motor Vehicles and Oregon Voter Registration Office. The combined lists included over 30,000 records. From August 2000 to September 2001, informational letters were sent randomly to 10,700 individuals. Individuals were asked to return a contact sheet with a phone number in a self-addressed, stamped envelope. Eight participants were recruited using existing volunteer resources at the Layton Aging and AD Research Center at OHSU. In addition to the DPS study data collection, the Layton Center data collection protocol was also followed.
Sample Size
- Number of Participants
- 89
- Number of Participants with Biological Samples
- 88
Data Collection Events
| # | Name | Data sources | Data sources - Biosamples | Start | End |
|---|---|---|---|---|---|
| 0 | OBAS - Study II - Evaluation OBAS II |
|
|
2000 (May) | 2013 (December) |
Participating Studies
| Acronym | Name | Study design | Countries |
|---|
Harmonization Initiatives Included
| Acronym | Name |
|---|
Datasets
| Name | Data Collection Events | Variables |
|---|
Areas of Information Collected
- Socio-demographic and economic characteristics
- Death
- Lifestyle and behaviours
- Physical measures and assessments
- Birth, pregnancy and reproductive health history
- Laboratory measures
- Perception of health, quality of life, development and functional limitations
- Cognition, personality and psychological measures and assessments
- Diseases
- Life events, life plans, beliefs and values
- Symptoms and signs
- Preschool, school and work life
- Medication and supplements
- Social environment and relationships
- Non-pharmacological interventions
- Physical environment
- Health and community care services utilization
- Administrative information
Variables Content Summary
Areas of Information Collected
Areas of Information Collected per per Population and Data Collection Event
Networks
| Acronym | Name | Harmonization Initiatives | Individual Studies |
|---|