From the German statutory health insurance database.
Medical records from AOK
History of joint replacement surgery
Dementia (clinical diagnosis using ICD-10 codes)
Included lag time; adjusted for cerebrovascular risk factors, age, sex, the presence of delirium, and regular prescription of sedative or analgesic drugs (SAD)
Adult Changes in Thought (ACT) cohort which was randomly selected from members of Group Health (GH). free of dementia
Self-reported data through interview at baseline and follow-upstudy visits
Self-reported anesthesia data (reviewed by anesthesiologist)
Dementia (DSM-IV) AD (possible or probable AD by NINCDS-ADRDA)
Did not included lag time; adjusted for ACT study cohort, age, age at study entry, sex, education, hypertension, diabetes mellitus, smoking, stroke, coronary heart disease, exercise, self-rated health, body mass index, depression, Parkinson’s disease, Charlson comorbidity index, and difficulty with activities of daily living.
Case: Swedish Dementia Quality Registry, diagnoses of AD, late-onset AD, early-onset AD, and mixed Alzheimer’s and vascular dementia in the county of Östergötland from May 2007 to April 2012 Control: selected from the Statistics Sweden
Medical records
Medical record of prior GA with gas
Dementia (diagnoses of AD, late-onset AD, early-onset AD, and mixed Alzheimer’s and vascular dementia from the dementia registry)
Did not included lag time; adjusted for age category, sex, hypotension under anesthesia, total time anesthesia, and number of exposures of anesthesia.
Case: residents in Shenyang, China, who were diagnosed with dementia between January 2007 and December 2012 Control: matched for every case via the medical reports archival system
Medical records from Chinese database of inhabitants of Shenyang
Medical record of prior GA
Dementia (DSM-IV) AD (DSM-IV)
Did not included lag time; matched for sex and age (within 1 year).
Case: newly diagnosed from 2005 to 2009 Control: 4-fold frequency matched
Medical records from the LHID
Record of endotracheal tube intubation GA
Dementia (clinical diagnosis using ICD-9-CM)
Did not included lag time; matched randomly by age (every 5 years of age), sex, and index year. Adjusted for age, sex, depression, diabetes mellitus, hypertension, stroke, and atherosclerosis.
Recruited at the Department of Neurological Sciences of “La Sapienza” University of Rome, who were treated between January 1990 and June 1997. Each case was matched for 4 controls (2 PD and 2 other disease)
Hospital records
Hospital record of exposure to GA in the 1-year and 5-year periods prior to onset of neurological disease.
AD (probable AD by NINCDS-ADRDA)
Did not included lag time; matched for sex, age (within 3 years), and geographical area of residence.
Case: selected from patients with AD developed between 1975 and 1984 in Olmsted County by reviewing medical records Control: matched for each AD case from Olmsted County Mayo Clinic patients
Medical records
Anesthesia records for GA
AD (clinical diagnosis using their own preselected specific criteria)
Recruited from both the community and institutions in Canada.
Risk factor questionnaires completed by proxy respondents
Surrogate-reported exposure to GA
AD (probable AD by NINCDS-ADRDA)
Did not included lag time; frequency matching by study center, residence in community or institution, and age group Adjusted for age, sex, residence, and education
Cases: Rochester, Minnesota, residents with onset of AD between 1960 and 1974 using the existing medical records resource. Controls: matched for each case by searching the registration system at Mayo Clinic.
Entire community medical records.
Medical record of prior GA
AD (clinical diagnosis by reviewing clinical and postmortem data)
Did not included lag time; matched by age (within years), sex, and duration of community medical record.
Cases: patients living in Washington state who were diagnosed with AD between January 1980 and June 1985. Controls: friend, relative or surrogate of the cases.
Interview with surrogate respondents
Surrogate-reported history of surgery with GA
AD (DSM-III, NINCDS-ADRDA)
Did not included lag time; matched by sex and age (within 10 years). Adjusted for age in the reference year.
Cases: from consecutive new referrals to dementia clinics in Sydney by general practitioners (GPs). Controls: a person matched for each case from same GP’s files.
Interview with the informants of the cases and controls
Surrogate-reported exposure to GA
AD (probable or possible AD by NINCDS-ADRDA)
Did not included lag time; matched for sex and age within 2 years. Matched pairs odds ratio was calculated.
Cases: Patients admitted to the neurology departments of the seven centers between 1982 and 1983. Controls: 1 hospital (from same hospital) and 1 population control (neighbor, a friend, or an acquaintance) was identified for each case
Interview with a surrogate respondent.
Surrogate-reported exposure to GA
AD (clinical diagnosis using their own criteria)
Did not included lag time; Matched for age (within 3 years), sex, and region of residence. Matched-pair analysis were used.
Cases: participants in a comprehensive clinical, genetic, and epidemiological study of AD at Duke University Medical Center. Control: 2 matched subjects selected by the telephone sampling technique of random-digit dialing.
Structured interview with a close family member.
Surrogate-reported history of surgery with GA
AD (clinical diagnosis using their own diagnostic procedure)
Did not included lag time; matched for sex, race, 5-year age interval (50-54, 55-59, etc.), and residential area.
Cases
40
Calculated OR 0.63 (0.20–1.96)
Controls
80
1.00
Abbreviations. : number of subjects; CI: confidence interval; HR: hazard ratio; OR: odds ratio; RR: relative risk; AD: Alzheimer’s disease; GA: general anesthesia; PC: prospective cohort study; RC: retrospective cohort study; NCC: nested case-control study; CC: case-control study; ICD-10: International Classification of Diseases, 10th Revision; ICD-9-CM: International Classification of Diseases, 9th Revision, Clinical Modification; DSM-III: Diagnostic and Statistical Manual of Mental Disorders, 3rd Edition; DSM-IV: Diagnostic and Statistical Manual of Mental Disorders, 4th Edition; NINCDS-ADRDA: National Institutes of Neurological and Communicative Disorders and Stroke-Alzheimer’s Disease and Related Disorders; AGECAT: Automated Geriatric Examination for Computer Assisted Taxonomy; NHIS-NSC: National Health Insurance Service-National Sample Cohort; LHID: Longitudinal Health Insurance Database; NHIRD: National Health Insurance Research Database; AOK: Allgemeine Ortskrankenkasse; CDR: Clinical Data Repository; CABG: coronary artery bypass graft; PTCA: percutaneous transluminal coronary angioplasty; PD: Parkinson’s disease; CHSA: The Canadian Study of Health and Aging.