Category Archive for: ‘Blood pressure’
Cardiovascular risk factors also associated with dementia
The risk factors – smoking, serum cholesterol, blood pressure, lung function and the presence of CVD at baseline – were associated with death from dementia. The risk was 58% greater for heavy compared to non-smokers, 55% greater for hypertensives compared to those with normal blood pressure, 73% greater for those with a high level of serum cholesterol, 46% lower for those with a high compared to a low lung function and 94% greater for those with a history of CVD at baseline compared to those with no such history. Men with a combination of two of the risk factors had a 2 times greater risk of death from dementia. These results suggest that that cardiovascular risk factors measured in midlife predict the risk of death with dementia.
Cardiovascular risk factors measured in the Seven Countries Study
Cardiovascular risk factors were measured at baseline and 160 out of 10,211 middle-aged men died from dementia during 40 years of follow-up. The results of the SCS suggest that cardiovascular risk factors affect the neurodegenerative process leading to dementia.
Smoking increases CHD risk
When the Seven Countries Study started in 1958 the prevalence of smokers was very high and ranged from 44% in Belgrade professors in Serbia to 78% in fisherman from Ushibuka in Japan. The 10-year follow-up data showed that smoking was associated with a higher risk of CHD mortality in countries where there were enough events for analysis and the strongest associations were observed in northern Europe where CHD was highest. An analysis using the 25-year CHD mortality data showed similar results.
Smoking a long-term predictor of CVD
The Finnish cohorts showed that the relative risk of CHD mortality among cigarette smokers compared to non-smokers decreased the longer the follow-up, but the excess CHD risk remained significant after 35 years of follow-up.
The 40-year data from the Zutphen Study showed that cigarette smokers at entry had a 59% higher CHD and a 66% higher CVD mortality risk compared to non-smokers. The duration as well as intensity of smoking was also independently predictive of CVD mortality.
- Keys et al. Harvard University Press, ISBN 0-674-80273-3, 1980:136-60
- Jacobs et al. Arch Intern Med 1999;159:733-40
- Qiao et al. Eur Heart J 2000;21:1621-6
- Streppel et al. Tob Control 2007;16:107-13
Blood pressure a strong predictor of CVD mortality
Systolic blood pressure in middle-aged men was an important predictor of 10-, 25-, 35- and 40-year CHD mortality in all cohorts. The 35-year follow-up data showed that past blood pressure levels are more important than recent values. Systolic blood pressure was also strongly associated with 25-, 35- and 40-year stroke mortality. Both recent and past blood pressure level were strongly predictive of stroke. The Zutphen Study found that the strength of the relation between blood pressure and 15-year stroke incidence doubled when 11 repeated casual pressures were measured. Blood pressure was also strongly related to 40-year total CVD mortality in the US railroad cohort.
Population differences in absolute CHD risk
The results after 10 and 25 years of follow-up showed that the relative risks from blood pressure level are similar across cohorts, while at the same level of blood pressure the absolute risks of CHD mortality are different. High absolute risk was present in Northern Europe and the United States and low risk in Mediterranean Southern Europe and Japan.
Relative risk of CHD associated with blood pressure is similar but absolute risk differs among the cohorts. This implies that elevated blood pressure levels need to be treated more intensely in high risk cultures to achieve target levels and potential prevention.
- Keys et al. Harvard University Press. ISBN 0-674-802733, 1980:103-20
- Keli et al. Stroke 1992;23:347-51
- Menotti et al. J Cardiovasc Risk 1996;3:69-75
- Menotti et al. Stroke 1996;27:381-7
- Van den Hoogen et al. N Engl J Med 2000;342:1-8
- Menotti et al. J Hypertension 2004;22:1683-90
- Menotti et al. Eur J Epidemiol 2004;19:417-24
- Boshuizen et al. Am J Epidemiol 2007;165:398-409