Circadian Rhythms and Cardiovascular Disease: Maximizing Therapy Using Biological Clocks

A new systematic review highlights a unique relationship between circadian rhythms and homeostatic processes governing cell death.

The review, published in Circulation, provided a general overview of circadian rhythms and focused their specific impact on cell-regulatory processes in cardiovascular diseases (CVD). Social media engagement for the review suggested great interest in the paper, generating more than 150 interactions on social media in its first 48 hours.

Circadian Rhythms and CVD

Circadian rhythm, they noted, can affect aspects of the cardiovascular system such as blood pressure. Atypical fluctuations of blood pressure during a 24-hour cycle can lead to an increase of fatal and nonfatal CVDs. They also noted that circadian rhythms can, at the cellular level, influence the impact and severity of cardiac injury following myocardial infarction (MI), and that MI incidence is greater in the early morning hours.

The authors noted that individuals who do shift work, and travelers with jet lag were perhaps most illustrative of the impact of shifting circadian rhythms and CVD risk.

“Concordant with these findings, the extent of myocardial injury following MI correlates directly with the time of day in which the ischemic insult occurred,” they wrote. “It is remarkable that 6 independent meta-analysis studies that examined the link between the effects of daylight-saving time shifts and the incidence of acute MI revealed that shifting the normal circadian rhythm by as little as 1 hour significantly influenced the incidence and risk for cardiovascular events.”

Chronotherapy

The authors also explored the subject of chronotherapy or setting therapy in accordance with circadian rhythms. The idea, they explained, was to “maximize the beneficial effects of drug therapy by coordinating treatment with the rhythmicity of the biological clock. This technique is used commonly with antihypertensive drugs, the researchers noted. They also highlighted research suggesting that chronotherapy has benefits for treating CVD, particularly with the administration of aspirin therapy, as well as other medications.

“The studies highlighted in this review lead to the novel suggestion that a window of optimal inhibition of cell death programs in a circadian-dependent manner is crucial for the maintenance of cardiovascular homeostasis and function,” the authors wrote in their conclusion.

The added that future studies should address the interactions between autophagy, programmed cell death, and circadian rhythms in normal diseased hearts.

“This will lead to innovative approaches to benefit treatment and outcomes for patients with CVD,” the wrote.

Source: Circulation