Related Experiment Video
Updated: Aug 23, 2026

Using Retinal Imaging to Study Dementia
Published on: November 6, 2017
[Circadian rhythm and encephalic vascular disease: a correlative study with risk factors]
Helio Araújo Oliveira1, Alvaro José Porto Moreira, Arthur Maynart Pereira Oliveira
1Serviço de Neurologia, Hospital Universitário, Universidade Federal de Sergipe, Aracaju, SE, Brasil. hélio@infonet.com.br
Abstract:
The human biological mechanisms show a predictable clinical variability in time, which has allowed a deeper reevaluation of present-day medical practices, regarding the circadian rhythm (CR) and the mechanisms that produce the supported variations in all biological levels. We have made a study aiming to relate the CR and onset of the neurological clinic situation due to the encephalic vascular lesion, correlating with modifying risk factors. Fifty three patients were studied, 50,94% female (n=27) and 49,50% male (n=26), at average age 66.4 years old. Four intervals of six hours each (0-6; 6-12; 12-18; 18-24) were used to analyze the frequency of the ictus and the incidence in each interval. We found an incidence of 6(11.32%) patients in the 0-6 hs interval; 21 (39.62%) patients in the 6-12 hs interval; 10(18.86%) patients in the 12-18 hs interval; 16 (30.18%) patients in the 18-24 interval. A correlative study with the risk factors has shown that arterial hypertension [(81.25%)] and smoking habit [ (56.25)] were predominant during the 18-24 hs interval, while sedentary [11(52.38%)] stress [11(52.38%)] diabetes [(47.61%)] hyperlipidemia [8 (38.09%)] and alcoholism [8 (38.09%] were predominant during the 6-12 hs interval; and cardiac diseases in the 12-18hs interval.
Related Concept Videos
Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
Cerebral Edema ll: Pathophysiology
Circadian Rhythms and Gene Regulation
Hemorrhagic Stroke ll: Pathophysiology
Increased Intracranial Pressure ll: Pathophysiology
Correlation between ECG and Cardiac Cycle
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
