Sleep disorders and cardiovascular disease risk

The relationship between sleep and the cardiovascular system is complex in both health and disease states, with sleep stage dependent influences on autonomic tone, heart rate and blood pressure. “Normal” nightly sleep duration and quality, definitions of which vary from person to person, are thought to be important in cardiovascular homeostasis as demonstrated by acute experimental sleep deprivation as well as recent population based data suggesting a higher prevalence of cardiovascular disease in those with chronic sleep deprivation. Epidemiologic and pathophysiological studies indicate possible causal links between sleep disturbances and risk factors for cardiovascular disease such as obesity and hypertension.

Obstructive sleep apnea (OSA), an exceedingly common disorder tightly linked to obesity, is an increasingly recognized public health burden. Characterized by repetitive upper airway collapse and de-oxygenation, OSA may form the substrate for acute cardiovascular diseases and be important in the development of chronic disorders such as hypertension and heart failure. Because OSA so frequently co-exists with these disorders, it is entirely conceivable that OSA treatment could be an important adjunct in the management or prevention of cardiovascular disease. Unfortunately, because few interventional trials have been conducted to date, the role of OSA treatment on cardiovascular outcomes remains unclear. Central sleep apnea (CSA) also has gained attention because of its association with heart failure. Current evidence suggests that CSA may perpetuate pathophysiologic mechanisms in heart failure. The relationship of sleep disorders and cardiovascular disease suggest that early detection and treatment of sleep disorders could reduce the prevalence of cardiovascular disease.