Orthostatic Disregulation (OD, a kind of dysautonomia) is a syndrome which indicates disfunction of vessel contraction reflex during static standing. OD patients often show some symptoms of fainting, dizziness, headache and the like or syncope when they are holding orthostatic posture. OD is more recognized especially in preadolescence and adolescence periods (9-15 yrs.) . Brück & Oltmann (1957), Okuni (1958) etc, have reported details about OD.
The purpose of this study was to obtain and discuss details relating to recent appearance of OD, physique, growth characteristics, cardio-vascular functions and physical fitness on OD children by the questionnaire method and some experiments.
2, 227 children in elementary and junior high school in Yokohama and Kamakura cities as sub jectswere first screened by the questionnaire. And 165 subjects out of 2, 227 were at random selected for data on Schellong standing test, passive head-up tilt and distance running.
The value of 9-29%, which was the ratio of false OD (+) appearance by the questionnaire method in this study, was recognized higher than the value of 5-20% by previous studies'. Physique on false OD (+) children was somewhat lean in comparison with the normal. And they had more height increase than the normal.
In physical fitness, distance running, 50 m dash, broad jump, ball throw, chinning exercise and back pull-over tests, OD children were inferior than the normal.
A concrete datum in syncope for standing was got in this study. When an OD child exhibited syncope, systolic blood pressure became 78 mmHg (rest 120-130 mmHg) and heart rate became 76 beats per minute (standing before syncope 100-110 beats per minute) . T wave in II, _aV_F and P wave in II, III (depression, negative waves etc.) of ECG varied from resting ECG. Judging from these data about ECG and blood pressure on standing test, passive head-up tilt, it was indicated that a reflex system of vessel contraction on OD child didn't work well, and that the heart of OD child was much stressed by gravity in orthostatic posture and changing posture than the normal.
In addition, a fact was proven that false OD (+) children (39.1% boys and 48.2% girls) didn't like sports and physical activities comparing with the normal (16.4% boys and 23.5% girls), It was statistically significant. Therefore, it is estimated that there is a relationship between appearance of OD and physical activities in daily life.