Sleep problems are often dismissed as minor lifestyle issues, but emerging research suggests they may have serious consequences for heart health. A large new study conducted by researchers at Yale School of Medicine has revealed that individuals who suffer from both Insomnia and Obstructive Sleep Apnea face a dramatically higher risk of developing heart-related conditions.
The research examined health data from nearly one million U.S. veterans and found that the combination of these two sleep disorders known as Comorbid Insomnia and Sleep Apnea (COMISA) can more than double the likelihood of developing Hypertension and increase the risk of Cardiovascular Disease by over three times.
Published in the Journal of the American Heart Association, the study highlights the importance of recognizing sleep disorders as a critical yet often overlooked factor affecting long-term cardiovascular health.
The research team analyzed medical records from 937,598 veterans receiving treatment within the U.S. Veterans Health Administration.
Participants were tracked over nearly two decades to understand how sleep disorders influenced their risk of developing cardiovascular conditions.
Key details about the study population include:
Median age: 41 years
Women participants: approximately 12 percent
Long-term monitoring period spanning nearly 20 years
The researchers found that individuals who experienced both insomnia and obstructive sleep apnea were significantly more likely to develop heart-related problems compared with those without sleep disorders.
The study revealed that the overlap of insomnia and sleep apnea created the highest cardiovascular risk among participants.
Compared with individuals who had no diagnosed sleep disorders:
Those with COMISA had more than double the risk of developing hypertension.
They faced over three times the likelihood of cardiovascular disease.
Researchers also discovered that even when these conditions occurred individually, they still raised the risk of heart problems, although not as dramatically as when both were present simultaneously.
Importantly, the study’s analysis showed similar trends among both men and women, indicating that the cardiovascular risks associated with combined sleep disorders affect people regardless of gender.
Insomnia is one of the most common sleep disorders worldwide. It is characterized by persistent difficulty falling asleep, staying asleep, or waking up too early and being unable to return to sleep.
People with chronic insomnia often experience:
Fatigue during the day
Reduced concentration
Mood disturbances
Poor overall sleep quality
When untreated, insomnia can contribute to multiple health problems, including stress, anxiety, and metabolic disorders.
Obstructive Sleep Apnea occurs when the airway becomes partially or completely blocked during sleep.
This blockage causes breathing to stop repeatedly throughout the night. These pauses may last several seconds and can occur dozens or even hundreds of times during sleep.
Common symptoms include:
Loud snoring
Gasping for air during sleep
Frequent awakenings
Excessive daytime sleepiness
The repeated interruptions prevent the body from reaching deep, restorative sleep stages.
Doctors refer to the coexistence of insomnia and sleep apnea as Comorbid Insomnia and Sleep Apnea (COMISA).
In the veteran population analyzed in the study:
About 14 percent had both conditions simultaneously
Around 13 percent suffered from insomnia alone
Approximately 21 percent experienced sleep apnea alone
These figures suggest that many individuals may suffer from overlapping sleep disorders without realizing it.
Researchers warn that treating only one condition while ignoring the other may leave patients vulnerable to serious health risks.
The study emphasizes that sleep plays a vital role in maintaining cardiovascular health.
During healthy sleep, the body performs several restorative processes:
Blood pressure naturally decreases
Stress hormone levels drop
The heart rate stabilizes
Blood vessels relax and recover
However, when sleep is repeatedly disrupted—as in insomnia or sleep apnea—these recovery mechanisms are impaired.
When sleep becomes fragmented or repeatedly interrupted, several harmful processes may occur:
Frequent awakenings and breathing interruptions can keep blood pressure elevated overnight, preventing the cardiovascular system from recovering.
Sleep disturbances can raise levels of stress hormones such as cortisol, placing additional strain on the heart.
Poor sleep may trigger inflammatory responses that damage blood vessels over time.
These disruptions can eventually lead to conditions such as:
Heart Failure
Stroke
Heart Attack
Researchers believe that the combination of insomnia and sleep apnea amplifies these harmful biological effects, explaining the significantly higher cardiovascular risks observed in people with COMISA.
The findings suggest that addressing sleep disorders early could help reduce the long-term burden of cardiovascular disease.
Sleep disturbances have several characteristics that make them important targets for preventive healthcare:
They are common across populations
They can be detected through medical screening
They are treatable with established therapies
Doctors increasingly believe that sleep health should be considered alongside traditional cardiovascular risk factors.
There are effective treatment strategies for both insomnia and sleep apnea.
One of the most widely used treatments for obstructive sleep apnea is Continuous Positive Airway Pressure (CPAP) therapy. The device keeps the airway open during sleep by delivering a steady flow of air through a mask.
Chronic insomnia can often be treated with Cognitive Behavioral Therapy for Insomnia (CBT-I). This therapy helps individuals change behaviors and thought patterns that interfere with sleep.
Experts say combining both approaches may be particularly beneficial for patients suffering from COMISA.
Traditionally, doctors have focused on well-known cardiovascular risk factors such as:
High cholesterol
Smoking
Obesity
Lack of physical activity
However, the findings from this large-scale study suggest that sleep disorders should also be considered an important indicator of heart health.
By identifying and treating insomnia and sleep apnea early, healthcare providers may be able to significantly reduce the risk of long-term cardiovascular complications.
As researchers continue to explore the relationship between sleep and heart disease, experts say prioritizing healthy sleep could become a central component of preventive medicine.