If you have high blood pressure and your blood pressure fluctuates significantly, you may be at a higher risk for stroke. A study of 686 dementia-free older adults, published in the May issue of the journal Archives of Neurology, found that those with the lowest fluctuations had about a 5.5 percent chance of having a stroke. Those with the highest fluctuations had a 14.2 percent chance. Having either hypertension or blood pressure fluctuations was independently associated with increased risk of cerebrovascular disease (which includes stroke and other disorders of the brains blood vessels). But the study found that the combination of both factors dramatically increases your cerebrovascular disease risk.