The sleep problem hiding in plain sight
Coronary heart disease (CHD) is the leading cause of death worldwide. It happens when the arteries that supply blood to the heart get narrowed or blocked — usually by a buildup of fatty deposits. Heart attacks, chest pain, and reduced stamina are common results.
Most cardiac care focuses on blood pressure, cholesterol, and medications. Sleep often gets left out of the conversation. But sleep is when the heart recovers. Poor sleep raises blood pressure, increases inflammation, and makes the heart work harder than it should.
What we used to miss
Doctors have long known that sleep apnea — where breathing stops during sleep — is dangerous for the heart. A lot of attention goes there.
But here's the twist: insomnia, which is simply the inability to fall asleep or stay asleep even when you have the chance, is actually more common than sleep apnea in adults. And until recently, very little was known about just how prevalent it is among people with heart disease.
Why the heart-sleep connection is so strong
Think of sleep as a nightly maintenance window for your cardiovascular system. During deep sleep, blood pressure drops, heart rate slows, and the body repairs inflammation. When that window gets disrupted night after night, the damage accumulates — like a machine that never gets switched off for servicing.
Insomnia disrupts this process constantly. And the conditions that often accompany heart disease — anxiety, depression, chronic pain, diabetes — all make insomnia worse. It becomes a self-reinforcing cycle that's hard to break.
What this study looked at
Researchers conducted a systematic review and meta-analysis — pulling together 19 studies involving 5,928 patients with confirmed coronary heart disease. They looked at how common insomnia was across these patients and what factors made it more likely. The work was published in Frontiers in Medicine in April 2026.
The pooled prevalence of insomnia was 51.8%. In plain terms: about one in two CHD patients meets the criteria for clinically significant insomnia. That's a striking number.
The analysis also identified the factors most strongly associated with insomnia in this group. Women were twice as likely as men to have insomnia. Depression raised the odds by more than two times, and gastritis (stomach inflammation) raised them even higher. Anxiety, diabetes, and having had heart disease for three or more years all significantly increased risk as well.
This means insomnia in heart disease patients isn't random — it follows patterns that doctors can identify and act on.
A condition that flies under the radar
Despite these numbers, insomnia is consistently underdiagnosed in cardiology settings. Patients rarely bring it up, and cardiologists rarely ask. Sleep is seen as a "soft" complaint compared to chest pain or shortness of breath.
But failing to treat insomnia in someone with heart disease may be letting a modifiable risk factor go unchecked. Treating depression, anxiety, and diabetes — all of which worsen insomnia — could have a compounding benefit for heart health too.
If you have coronary heart disease and you're struggling to sleep, bring it up with your doctor. Don't wait to be asked. Mention how long you've been having trouble, whether anxiety or low mood plays a role, and whether conditions like diabetes or stomach problems are part of your picture.
Cognitive behavioral therapy for insomnia (CBT-I) is a proven, medication-free treatment that works well even in people with other health conditions. Some sleep medications are also appropriate for cardiac patients. The key is getting the conversation started.
Limitations to keep in mind
The 19 studies in this review came from different countries and used different ways to measure insomnia — some relied on questionnaires, others on clinical interviews. This variation can affect how comparable the results are. The majority of participants were from China, which may limit how well the findings apply to other populations.
Researchers are calling for insomnia to be formally included in cardiac rehabilitation programs and post-heart-attack care protocols. Future clinical trials need to test whether actively treating insomnia in CHD patients can improve heart outcomes — not just sleep. That research is only beginning, but the case for taking sleep seriously in cardiac care has never been stronger.
