Synchronizing antihypertensive medication timing with a patient's natural sleep-wake cycle could significantly reduce the risk of non-fatal heart attacks, according to a study from the Chronotype sub-study of the TIME trial.
Background
Circadian rhythms, the body's natural 24-hour cycles, affect various physiological functions, including blood pressure. Chronotype, a marker of an individual’s circadian rhythm, varies significantly among people, with "morning types" (early risers) and "evening types" (late risers) representing the extremes. Previous studies suggested that the timing of antihypertensive medication might impact its efficacy, but the role of chronotype had not been explored until now.
Methods
The Chronotype sub-study, published in eClinicalMedicine, was part of the larger TIME trial, a UK-based clinical trial investigating the effects of morning versus evening dosing of antihypertensive medications. From August 2020 to March 2021, 5358 participants completed a chronotype questionnaire, which categorized them as morning, intermediate, or evening types based on their sleep patterns. Researchers then analyzed the interaction between chronotype, medication dosing time, and cardiovascular outcomes, focusing on hospitalizations for non-fatal myocardial infarction (MI) and stroke.
Findings
The study found a notable interaction between chronotype and dosing time for non-fatal MI but not for stroke. Key findings included:
- Evening Dosing for Evening Types: Evening types (those who slept later) had a significantly lower risk of non-fatal MI when taking antihypertensive medication in the evening compared to the morning.
- Morning Dosing for Morning Types: Morning types (those who woke earlier) experienced a reduced risk of non-fatal MI when taking their medication in the morning rather than in the evening.
- Intermediate Types: No significant difference in cardiovascular outcomes was observed for intermediate chronotypes, regardless of dosing time.
Interpretation
These results suggest that personalizing the timing of antihypertensive medication to align with an individual's chronotype could provide additional protection against heart attacks. While the risk of stroke did not show a similar interaction, the findings underscore the potential of chronotherapy in enhancing treatment efficacy for hypertension.
Implications
This study opens the door to more personalized approaches in hypertension management. By quickly assessing a patient's chronotype, healthcare providers could tailor medication schedules to better match natural circadian rhythms, potentially improving cardiovascular outcomes. Further research is needed to confirm these findings and explore the broader applications of chronotherapy in hypertension and other chronic conditions.
Funding and Acknowledgements
The TIME study and its Chronotype sub-study were funded by the British Heart Foundation, with additional support from the British and Irish Hypertension Society.