Descriptions of health status

Health history abstracts. Health history data for the longitudinal study participants were obtained from time of entry into the study through 1998 for all participants remaining in the study and for those who dropped out for the 7 years following their last assessment, or until their death if the latter occurred earlier.

Health history data consist of the number of annual physician visits or hospital days by diagnosis (coded according to the International Classification of Diseases, ICDA, 8th edition until 1984; 9th edition thereafter). In addition, the number of continuous illness episodes per year are also coded.

Health histories were physically abstracted by medical librarians until 1991. Data thereafter come from the computerized HMO records.

Medication reports. Beginning with the sixth (1991) cycle, medication data have been collected by means of a brown bag procedure, in which subjects bring their current medications to the testing site, where the medication identifiers are recorded. Diseases for the treatment of which these medications are prescribed are identified using the procedure advocated by the American Society of Hospital Pharmacists (1985). In addition we were able to obtain complete computerized pharmacy record for the four-month window preceding the actual testing date for all subjects participating in the seventh (1998) cycle.

Identification of relatives with dementia. Beginning with the sixth cycle we asked all participants to list blood relatives who they thought had been diagnosed as suffering from Disease of the Alzheimer’s Type (DAT). Information was also sought on whether such relatives were still living and, if dead, their age at death.

Blood samples. Since 1998 we have been able to obtain blood samples from most participants over age 60 within a one-month window of the psychological assessment. Data obtained from the blood samples consist of ApoE genotypes, a lipid profile, homocysteine and C-Reactive Protein. Blood cells have been cryopreserved for potential future genetic analyses.

Health behavior questionnaire (HBQ). An 85-item health behavior questionnaire covering preventive health behaviors and health practices was developed and first administered to participants in the sixth cycle and the first family study in 1993. The questionnaire continues to be administered in all subsequent data collections. The HBQ has been factored and represents seven clusters of health behavior, as well as a measure of subjectively reported health status.‚Äč