Risk factors for clinically diagnosed Alzheimer's disease: a case-control study of an Italian population

The inheritance of Alzheimer's disease: a new interpretation

Ninety-one families of Alzheimer patients were studied to determine the proportion of familial cases, to obtain pedigrees for the analysis of the mode of inheritance, and to look for clinical differences between the familial and the nonfamilial cases. The diagnosis was confirmed by autopsy in 26 cases. Thirty-nine cases (43%) were familial, which is defined as more than one case in the family. Our interpretation of the pedigree data is that Alzheimer's disease is etiologically heterogeneous: it may be genetic or sporadic. In the familial type we think that the disease is inherited as an autosomal dominant, with a wide range of age of onset within a family. In one-third of these families the gene is not expressed until over age 70. No clinical differences were found between the familial and the sporadic groups.

Italian multicenter case-control study of clinically diagnosed Alzheimer disease: strategies and instruments for data collection

Instruments and methods used for data collection in the Italian multicenter case-control study of clinically diagnosed Alzheimer disease are illustrated. Details of design of the questionnaire, choice and training of the interviewers, choice of the respondent, and assessment of the quality of data collected are discussed. The text of the questionnaire is included.

Organic solvents and presenile dementia: a case referent study using death certificates

Occupational exposure to organic solvents has been implicated in the development of "presenile dementia" in several studies. The death certificates of all men aged under 65 dying in England and Wales bearing presenile dementia as cause of death were collected for the years 1970-9 (n = 557): control death certificates were obtained, matched for age and sex. No significant differences were found between the groups as regards estimated occupational exposure to either organic solvents or lead.

The use of surrogate respondents to obtain questionnaire data in case-control studies of neurologic diseases

In 1984-85, the authors assessed the reliability of surrogate respondents to provide interview data for the specific items of a case-control study of Alzheimer's disease conducted in Italy. For all questions of the interview, responses of 52 non-demented subjects were compared to responses of their next-of-kin. In 21-27% of the pairs the next-of-kin was unable to answer questions about general anesthesia, antacid drug use, and age of mother and father at index birth. However, the surrogate respondent was able to answer 45 of 57 tested items with agreement greater than 80%. Questions about use of hard liquor and behavior pattern yielded agreement of 71-75%, while those about number of jobs, and number of cigarettes per day yielded 62-63% agreement. For those who provided information about antacid drug use, agreement was poor. These findings are encouraging for the use of next-of-kin respondents in case-control studies of Alzheimer's disease or other neurologic conditions for which the subject cannot provide historical information.