For Many, Sleep Could be the Heart of the Matter
Sleep-related breathing disorders such as sleep apnea are as important a predictor of heart disease risk as smoking, diabetes, or high blood pressure, according to research conducted by Neomi Shah, MD, Assistant Professor of Medicine (Pulmonary Medicine) and Associate Director of the Montefiore Medical Center Sleep Laboratory.
Sleep Apnea May Worsen AMI Outcomes
Obstructive sleep apnea (OSA) is one of the most common sleep disorders in the United States, affecting an estimated 24% of men and 9% of women. OSA is marked by the collapse of the upper airway, which results in disrupted breathing and decreased oxygen supply to the heart and body tissues. OSA may be particular critical in patients who have experienced acute myocardial infarction (AMI, or heart attack), as oxygen deprivation may cause further injury to the already-damaged heart muscle. While evidence suggests that sleep apnea is an important risk factor for the development of a myocardial infarction, performing regular sleep studies on all of these patients being admitted with an AMI would be prohibitively time-consuming and costly. Shah, whose past research at the Yale Sleep Center examined over 1,000 patients and strengthened the association between sleep-disordered breathing and increased risk of coronary artery disease and death, is now collaborating with Division of Cardiology investigators to determine whether the Berlin Questionnaire, a survey developed in 1996 with questions about OSA risk factors (e.g., snoring, sleepiness, and the presence of obesity or hypertension), would be an effective diagnostic tool for post-AMI patients. “The Berlin Questionnaire takes about five minutes for the patient to complete, and captures a lot of the common symptoms that present with sleep apnea,” said Shah. “It has also been validated in a study with over 95% sensitivity and specificity.”
Women May be Underdiagnosed, at Increased Risk
While sleep apnea has historically been thought to affect more men than women, over 90% of women with OSA may be undiagnosed, partly because OSA affects women differently (presenting as depression, lack of energy, or insomnia rather than the snoring, daytime sleepiness, or witnessed apneas [disrupted breathing] seen in their male counterparts). Recent studies have brought light to the issue of whether women are at increased risk for atherosclerosis and other effects of OSA on the cardiovascular system when compared to men with similar degree of OSA severity. Shah, whose own mother regularly sleeps with a continuous positive airway pressure machine (CPAP) to control her OSA, is co-investigator in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), led by prinicipal investigator Dr. Robert Kaplan, a multicenter study examining health disparities among a population of 16,000 Hispanic/Latino individuals, where she will develop a gender-specific prediction equation for OSA and examine the role of gender on the relationship between OSA and atherosclerosis.
Overcoming the Parenting/Sleep Challenge
As a working mother (she and her husband Samit Desai, MD, an infectious disease specialist, are parents to 18-month-old twin boys) who continually juggles the demanding and often conflicting roles of researcher, educator, and clinician, Shah prioritizes sleep. “I have to practice what I preach,” she said. “When my sons were six months old we put them to bed and let them cry it out. Now they get eleven hours of sleep a night and I get about seven and a half.” (video: Parenting and Sleep )
As more is known about the critical role of sleep on cardiovascular health, Shah and her colleagues’ work is paving the way for changes in how patients with traditional risk factors for AMI are screened for OSA, and may provide critical intervention for improved outcomes. “If patients have sleep apnea they're not going to feel good no matter how well they're treated for their MI,” Shah said. “My goal is to figure out if sleep apnea does impact outcomes, including not just heart-related but also quality of life.”