Scientists from Columbia University Medical Center have started enrolling women in a multifaceted study to uncover the link between sleep patterns and heart disease. The funding was provided by American Heart Association. The funds also supported the foundation of a center within the department of medicine to investigate and study abnormal sleep patterns as a risk factor for developing heart disease in women.
This study was partly motivated by the fact that many women consider not getting enough sleep as a contributing factor in heart disease, after being asked in a recent national survey to name the things they could do to reduce their risk of heart disease. The most popular choice they selected was to get more sleep.
Lori Mosca, Columbia University’s scientist/physician, believes that despite wide spread belief about the association between the two, there is not enough concrete evidence to support these claims.
Mosca said, “That’s not surprising. There are multiple studies that have found associations between ‘short sleep’ and heart disease and these are widely reported in the media. It’s been a big debate among researchers in the field. We’re not really sure if lack of sleep actually causes the increased risk or if the two are just correlated.”
The first phase of the trial will involve recruiting 500 women aged between 20 and 79 for a population based study. The study will focus on investigating sleep patterns and other potential risk factors that can lead to heart disease in women, such as caregiving, menopause and relationship stressors.
In the second phase of the trial, study participants will be invited to enroll in a clinical trial in which they will be asked to reduce their sleep duration by 90 minutes each night for six weeks. A tracking device known as an accelerometer will be worn by the participant women, on their wrists, to keep track of hours they sleep.
A baseline will be established and the impact of sleep restriction on diet, exercise habits, body fat measurements and risk factors for cardiovascular disease will be compared with results when sleep patterns are at baseline value.
According to Assistant Professor Dr Marie-Pierre St-Onge, previous studies have produced mixed results. Some studies show that heart disease risk factors, particularly a type of pre-diabetes, can be improved by getting more sleep. However, there is limited research on the effect of getting more sleep on inflammation or cholesterol profiles that could also lead to heart disease in women. Dr St-Onge will be conducting trials to see if lack of sleep is also a contributing factor in heart disease in women.
Dr St-Onge added, “If the answer is yes, that means we should include lack of sleep as a major lifestyle risk factor in standard screening guidelines for heart disease in women, just as we include smoking, physical activity and diet.”
The third stage in the study will involve taking a closer look at the molecular level of the biological processes involved. Scientists will examine the molecular changes that take place when the women reduce their sleep and assess how these changes could lead to heart disease.
Dr Sanja Jelic, who is a sleep apnea expert, believes that changes in blood vessel lining cells may be a contributing factor, and she has used her experience to directly analyze changes that occur in those cells. She used this technique in her previous studies on sleep apnea.
Sleep apnea is a serious medical condition that affects the breathing patterns during sleep. In this condition, a person has multiple starts and stops in breathing. Dr Jelic mentioned that the end goal was to determine whether sleep deprivation had any effect on vascular function and to figure out the underlying mechanisms behind it.
She further added that being familiar with the underlying processes may enable physicians to discover new avenues to improve vascular health in individuals who are not getting the amount of sleep that they should.
The researchers understood that there may be times when an individual might not have time in their schedules to get adequate sleep. Instead they reminded that there are tips to counter the health problems related to not getting enough sleep.
According to Dr Aggarwall, “If someone is not getting enough sleep because they have small children or because of hormonal changes during and after menopause, it’s important to try to focus on managing the well-established lifestyle risk factors for heart disease as best as possible. These include keeping a healthy diet, being physically active, maintaining a normal body weight for height, not smoking, and not drinking excessive amounts of alcohol.”
Having a healthy diet and being physically active are important factors to consider in general and especially when not getting enough sleep. Quality of sleep is another aspect that matters a lot.
Fitness tracking devices, or wearable, are equipped to calculate sleep cycles, and may give a better idea about how many times you wake up during the night. Technology can also help provide scientists with sleep patterns of women.
A study published in Science Advances has found that women sleep more than men. The study also revealed that people from Netherlands get more sleep than people from Japan and Singapore. The data was gathered using the Entrain app, which was developed by a team of researchers at the University of Michigan to help people overcome jetlag. Users had the option to share their sleeping pattern data with the team so they could better assess the overall global sleep situation.
Another important thing to consider is that these trials will only focus on women. To have a better estimate, future studies should focus on both men and women, since there might be patterns that are different due to biological differences such as hormones, weight and height.