To make sure whether Systolic Time Intervals (STI) is useful in predicting cerebrovascular disease earlier, an analysis of the main components by the Jacoby method were made on 120 men and women ranging in age from 17 to 80. Provided that valuables are age, systolic blood pressure (st), (et/ict) cardiac stroke volume (Kv), arteriolar pulse wave compliance (comp), systolic heart radius (scrad), faculty coefficient (fi), and heart rate (hr), the subjects could be divided into two-healthy group (first major component) and hypertensive/cardio-mulfunction group (second component). This fact shows that the use of STI is effective in analyizing the function of the heart and the blood vessel system. It also proved that cardiac stroke volume and arteriolar pulse wave compliance measured by STI decreased in the cases of hypertension in which afterload rises with the elapse of time and the cases of atrial fibrillation marked by disordered diastolic period due to irregular RR intervals. These conditions, if sustained long, could cause cerebral apoplexy to occur.
The cases of cerebral apoplexy were studied retrospectively. Six months before onset, arteriolar pulse wave compliance had decreased. Three months before onset, ICT and heart radius between beats had increased, while KV, ET/ICT and FI lowered. And one month before onset, systolic blood pressure rose.
From the foregoing, the lowering of arteriolar pulse wave compliance, heart contraction and cardiac output, and the increase in the heart radius in the systolic period are considered the major forebodings of cerebral apoplexy.

Cerebrovascular disease is still considered a serious health problem in Japanese rural areas. The rate of death from the disease is very high. Many clinical and epidemiological studies have been conducted so far. However, they have failed to come up with answers effective for prediction and prevention of the scourge.
As part of the agricultural coop commissioned research project entitled “Study of Cerebral Apoplexy: Its Prediction and Prevention, ” we took a questionnaire survey in 1985-86, to obtain data as regards patients' subjective symptoms, electrocardiographic observations, hematological findings and many others before the onset of cerebral apoplexy. Five medical research institutes affiliated with the national welfare federation of agricultural cooperatives responded to our questionnaire.
As a result, the subjective symptoms that showed stochastically significant increases from one year to three months before the onset of the disease as a whole were fatigue, forgetfulness and insomnia. When it comes to cerebrovascular infarction, shortness of breath, angina, forgetfulness, and nocturia were particularly notable.
All these symptoms are not peculiar to cerebral apoplexy, but it should be noted that these are the warning signals of the killer disease.