Health

A new study published in the Journal of the American Heart Association reveals a significant link between sleep disorders – specifically the combination of insomnia and obstructive sleep apnea – and an increased risk of hypertension and cardiovascular disease among U.S. Military veterans. The research, which analyzed data from nearly one million post-9/11 veterans, highlights the critical need for identifying and addressing sleep disturbances as a key component of cardiovascular prevention.

The study underscores a growing understanding of the interconnectedness between sleep health and overall cardiovascular well-being. Veterans, who already demonstrate a higher predisposition to hypertension and cardiovascular disease compared to the general population, face an even greater risk when grappling with both insomnia and sleep apnea simultaneously. This combination, termed COMISA (Comorbid Insomnia and Obstructive Sleep Apnea), appears to be particularly detrimental.

COMISA and Cardiovascular Risk: Key Findings

Researchers found that veterans with COMISA exhibited a substantially elevated risk of developing hypertension. According to the study, the adjusted hazard ratio for hypertension was 2.43 (95% CI: 2.36-2.50) for those with COMISA, indicating a more than twofold increase in risk compared to veterans without any sleep disorder [1]. This risk was observed across both men and women, though the specific hazard ratios differed slightly by sex.

“Compared with veterans who had no sleep disorder, those with COMISA showed the highest risk of developing hypertension,” stated Allison Gaffey, PhD, lead author of the study and researcher at the VA Connecticut Healthcare System and Yale School of Medicine [2]. The research team utilized administrative and electronic health record data to identify cases of insomnia and obstructive sleep apnea, defined by diagnostic codes and medication fills.

Understanding the Impact of Sleep Apnea and Insomnia

Obstructive sleep apnea (OSA) is a condition where breathing repeatedly stops and starts during sleep, leading to oxygen deprivation and disrupted sleep patterns. Insomnia, is characterized by difficulty falling asleep, staying asleep, or experiencing non-restorative sleep. When these two conditions coexist, the negative effects on cardiovascular health appear to be amplified. The study suggests that the combined stress on the body – from oxygen fluctuations in OSA and the chronic hyperarousal associated with insomnia – contributes to the increased risk of hypertension and cardiovascular disease.

The study included 937,598 post-9/11 Veterans with a median age of 41 years, with 12% being women [5]. Researchers adjusted for a range of demographic, behavioral, and clinical factors to isolate the specific impact of COMISA on cardiovascular outcomes.

Implications for Veteran Healthcare and Beyond

The findings have significant implications for healthcare providers treating veterans, as well as for the broader medical community. The study emphasizes the importance of routinely screening for both insomnia and obstructive sleep apnea in patients at risk for cardiovascular disease. Early identification and intervention – including lifestyle modifications, cognitive behavioral therapy for insomnia, and continuous positive airway pressure (CPAP) therapy for sleep apnea – may assist mitigate the increased cardiovascular risk associated with COMISA.

“Identifying disordered sleep among men and women should be a cardiovascular prevention priority,” the study authors conclude [5]. The research too highlights the need for further investigation into the underlying mechanisms linking sleep disorders and cardiovascular disease, which could lead to the development of more targeted and effective prevention strategies.

The study, published December 11, 2025, builds on existing research demonstrating the link between sleep disturbances and cardiovascular health. A 2025 study published in J Am Heart Assoc further confirmed these associations in a veteran population [4]. The growing body of evidence underscores the importance of prioritizing sleep health as an integral part of overall cardiovascular care.

Looking ahead, researchers plan to explore the potential benefits of integrated sleep disorder treatment programs for veterans, as well as investigate the impact of COMISA on other health outcomes, such as cognitive function and mental health. Continued research and proactive clinical management are essential to address the significant health challenges posed by sleep disorders and their connection to cardiovascular disease.

Have you or a loved one experienced challenges with sleep and cardiovascular health? Share your thoughts in the comments below.

Disclaimer: This article provides informational content and should not be considered medical advice. Please consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.

Our muscles possess a surprising ability to “remember” past experiences, even periods of inactivity, according to new research published this month. This ‘molecular memory’ impacts how skeletal muscle responds to disuse, with older muscles exhibiting a more detrimental response than those of younger adults. The findings, published in bioRxiv, could have significant implications for understanding age-related muscle loss and developing more effective rehabilitation strategies.

The study, led by researchers at the Norwegian School of Sport Sciences and the University of Pavia, reveals that repeated periods of disuse leave a lasting imprint at the molecular level within muscle tissue. This imprint affects the muscle’s ability to recover and rebuild strength after periods of inactivity. Understanding this phenomenon – often referred to as ‘muscle memory’ – is crucial as muscle disuse is a common factor in aging, illness, and injury.

Researchers found that young adults demonstrated a degree of resilience following disuse, with their muscles showing a quicker return to baseline function. However, aged muscle exhibited a more pronounced and lasting negative impact, characterized by greater atrophy – the wasting away of muscle tissue – and a suppression of genes responsible for aerobic metabolism. This suggests that prior disuse events can create a vulnerability in older muscles, making them more susceptible to further decline.

Molecular Mechanisms Behind Muscle Memory

The research team investigated the molecular mechanisms underlying this ‘muscle memory’ effect. They discovered that repeated disuse leads to changes in gene expression within muscle cells. These changes aren’t simply a direct result of the disuse itself, but rather represent a lasting alteration in the muscle’s molecular profile. The study highlights the role of transcriptional regulation – the process by which genes are turned on or off – in establishing this memory. Specifically, the researchers focused on mTORC1, a key regulator of muscle protein synthesis, and its impact on muscle adaptation. Further research has explored the molecular basis of mTORC1 and its role in muscle adaptation.

“What’s remarkable is that the muscle seems to ‘remember’ previous bouts of disuse, and this memory influences its response to subsequent challenges,” explains Dr. Daniel C. Turner, one of the lead authors of the study. “In younger individuals, this memory appears to be adaptive, promoting a quicker recovery. But in older adults, it seems to be detrimental, exacerbating the negative effects of disuse.”

Implications for Aging and Rehabilitation

The findings have important implications for addressing age-related muscle loss, known as sarcopenia. As people age, they naturally experience a decline in muscle mass and strength, which can lead to reduced mobility, increased risk of falls, and a diminished quality of life. The study suggests that interventions aimed at preventing or reversing muscle disuse may be particularly important for older adults. Recent analysis suggests that understanding the molecular characteristics of skeletal muscle is key to healthy aging.

the research could inform the development of more effective rehabilitation programs for individuals recovering from injury or illness. By understanding how muscles ‘remember’ past experiences, clinicians may be able to tailor interventions to optimize recovery and prevent future decline. The study also notes that muscle disuse atrophy does not appear to affect skeletal muscle satellite cell content, according to research from 2020.

The researchers emphasize that further investigation is needed to fully elucidate the mechanisms underlying muscle memory and to identify strategies for harnessing its potential to promote muscle health throughout the lifespan. Ongoing research is focused on identifying specific molecular targets that can be manipulated to enhance muscle resilience and improve recovery from disuse. The team is also exploring the role of exercise and nutrition in modulating the muscle memory response.

This research underscores the importance of maintaining physical activity throughout life to preserve muscle health and function. As we learn more about the remarkable plasticity of skeletal muscle, One can develop more targeted and effective strategies to combat age-related decline and promote healthy aging.

What are your thoughts on the implications of this research for exercise and rehabilitation? Share your comments below, and please share this article with anyone who might discover it informative.

Disclaimer: This article is for informational purposes only and should not be considered medical advice. Please consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.