ANALYSIS OF FAMILIAL AND INDIVIDUAL RISK-FACTORS AMONG PATIENTS WITH ISCHEMIC VASCULAR DEMENTIA AND ALZHEIMERS-DISEASE

The purpose of this study was to determine relative contributions of f irst-degree familial and individual risk factors to clinical manifesta tions of two major age-related dementias. The authors interviewed 183 patients with dementia of the Alzheimer's type (DAT) and 137 patients with ischemic vascular dementia (IVD) together with family members and caregivers. Information was also obtained from medical records and co llateral sources as required. Risk factor data within a predictive mod el for differentiating the two dementias were evaluated. There was a g reater incidence of family history of degenerative and dementing neuro logic disorders in DAT than in IVD. Both groups were equivalent for fa mily histories of cerebrovascular disease. Despite familial equivalenc e, patients with IVD had a greater individual incidence of risk factor s for cerebrovascular disease. Analysis by gender revealed three obser vations. Among DAT patients, family history for degenerative and demen ting neurologic disorders proved to be significantly greater among wom en than among men. This risk factor did not, however, predict individu al diagnoses for DAT. Women with IVD were more likely to have a family history of cancer than men. Multiple regression analyses revealed tha t reduced educational levels in women predicted greater liability for IVD than for DAT. Hypertension, heart disease, and diabetes mellitus w ere all risk factors for IVD, but not for DAT. Conclusions: Individual and familial historical data provide useful information concerning id entification, pathogenesis, prevention, and treatments for vascular de mentia but little predictive information for identifying patients with Alzheimer's disease.