Midlife vascular risk factors and Alzheimer's disease in later life: longitudinal,population based study

Objective To examine the relation of midlife raised blood pressure and serum cholesterol concentrations to Alzheimer''s disease in later life.Design Prospective, population based study.SettingPopulations of Kuopio and Joensuu, eastern Finland.ParticipantsParticipants were derived from random, population based samples previously studied in a survey carried out in 1972, 1977, 1982, or 1987. After an average of 21 years'' follow up, a total of 1449 (73%) participants aged 65-79 took part in the re-examination in 1998.Results People with raised systolic blood pressure (⩾160 mm Hg) or high serum cholesterol concentration (⩾6.5 mmol/l) in midlife had a significantly higher risk of Alzheimer''s disease in later life, even after adjustment for age, body mass index, education, vascular events, smoking status, and alcohol consumption, than those with normal systolic blood pressure (odds ratio 2.3, 95% confidence interval 1.0 to 5.5) or serum cholesterol (odds ratio 2.1, 1.0 to 4.4). Participants with both of these risk factors in midlife had a significantly higher risk of developing Alzheimer''s disease than those with either of the risk factors alone (odds ratio 3.5, 1.6 to 7.9). Diastolic blood pressure in midlife had no significant effect on the risk of Alzheimer''s disease.Conclusion Raised systolic blood pressure and high serum cholesterol concentration, and in particular the combination of these risks, in midlife increase the risk of Alzheimer''s disease in later life.

What is already known on this topic

Vascular risk factors may play an important part as risk factors for Alzheimer''s diseaseNo population based studies have evaluated prospectively the impact of both midlife blood pressure and cholesterol concentration in both men and women on the subsequent development of Alzheimer''s disease

What this study adds

Raised systolic blood pressure and high serum cholesterol concentration, and in particular the combination of these risks, in midlife increased the risk of Alzheimer''s disease in later lifeRaised systolic blood pressure and hypercholesterolaemia may have a role in the pathogenesis of Alzheimer''s disease; more emphasis should be placed on identification and appropriate treatment of these conditions