MedicalResearch.com Interview with:
Dr. Swati Gulati, MD Internal Medicine
John H. Stroger Hospital of Cook County
Medical Research: What are the main findings of the study?
Dr. Gulati: We conducted an observational study by providing questionnaire about the onset and progression of sleep apnea symptoms to patients seen in our sleep clinic for CPAP set up. In our cohort, mean age at the onset of snoring was 28 years and the mean age at diagnosis was 52 years. There was a lag of almost 23 years between the onset of snoring and the diagnosis of sleep apnea. The snoring started in mid twenties (Phase I) and patients noticed poor concentration and headaches in mid thirties (Phase II). Later, patients developed cardiopulmonary symptoms in mid forties to the time of diagnosis (Phase III).
The evolution of simple snoring into apneic episodes occurred around 40 years of age after which there was a rapid progression of disease marked by development of Excessive daytime sleepiness (EDS), dyspnea and morning headaches. We also found that patients who had started snoring earlier or at a very young age had a more severe disease as documented by apnea-hypopnea index (AHI).
In the literature, most of the natural history studies have looked at the progression of sleep apnea after diagnosis with a shorter follow up period ranging from 6 to 10 years. Through our study, we have aimed to determine the natural history of disease progression from simple snoring until the time of diagnosis.
Medical Research: What was most surprising about the results?
Dr. Gulati: We were surprised to find out that the symptoms of snoring started in the mid twenties and progressed over 2 decades before diagnosis. It was also surprising that the duration of snoring and change in weight were better predictors of obstructive sleep apnea (OSA) severity than the patient characteristics at the time of diagnosis, such as age and BMI. In our study, weight gain per year was the strongest predictor of severity of sleep apnea and it made the BMI at the time of diagnosis insignificant. Surprisingly, we found no association between gender and AHI.
Medical Research: What should clinicians and patients take away from your report?
Dr. Gulati: Based on our study, snoring in these patients starts at an early age and not necessarily in the middle age. Evolution of simple snoring into sleep apnea and symptomatic manifestations takes at least a decade on average.
Significant symptoms of sleep apnea were ignored for at least 20 years by the patients or their physicians. This should provide ample time opportunity for physicians to screen patients for sleep disordered breathing. Timely screening and diagnosis of obstructive sleep apnea will lead to early initiation of treatment and will slow its progression.
Medical Research: What recommendations you have for future research as a result of this study?
Dr. Gulati: Since our study population consisted of patients with severe OSA, these findings should be tested on a sample of patient that includes mild to moderate OSA. Randomized controlled trials should be done to see if screening for snoring in young adults and initiation of early treatment can prevent the development of OSA and associated mortality.
Progression of Symptoms of Obstructive Sleep Apnea and Their Association With Its Severity at Diagnosis?
Swati Gulati; Aiman Tulaimat
Chest. 2014;146(4_MeetingAbstracts):946A. doi:10.1378/chest.1992430