We thank Dr. Hunasikatti for his comments and insight.1 The findings of our study challenge the current but weak recommendation of repeating an in-laboratory polysomnography (PSG) for the diagnosis of obstructive sleep apnea (OSA) if the initial PSG results are negative and when there is clinical suspicion for OSA.2 Our study examined patients who underwent in-laboratory PSG and subsequent home sleep apnea test (HSAT) between 2012 and 2015 and were keeping with the recommendations at that time.3 The initial choice was also based on patient preference, insurer mandates, and requirements.
It is important to recognize that the aim of our study was not to disprove the utility of PSG as the second test if the initial PSG is negative, but rather examine a different paradigm using HSAT as a second test in a specific clinical population.
In our article, we acknowledge the comment that the night-to-night variability in the respiratory event index might have accounted for the positive HSAT results, particularly in patients with mild OSA, but our results reflect similar “overestimation bias” noted by Prasad et al.4 It is important to emphasize that in mild OSA, the use of the apnea-hypopnea index as a diagnostic indicator alone is problematic and that providers must also consider the clinical relevance.
Although we acknowledge the concern, we do not agree that false-positive HSAT results could have confounded the results of our study. Studies comparing apnea-hypopnea index predictability for type III monitors compared to PSG point to a high specificity that increases with rising degree of OSA severity.5 Moreover, patient outcomes of sleepiness or quality of life are similar in patients with OSA diagnosed with an HSAT versus PSG with positive airway pressure treatment.2
Finally, the roles of in-laboratory PSG and HSAT in the diagnosis of OSA are well established.2 Our study provides insight into repeat testing using HSAT in older patients with hypertension and high clinical suspicion for OSA after an initial negative PSG. Application of HSAT in this role might identify patients with OSA who are otherwise underdiag-nosed, but further studies are needed.
All authors have seen and approved the manuscript. The authors report no conflicts of interest.
Lipatov K, Ghamande S, Jones S. Response to Dr. Hunasikatti. J Clin Sleep Med. 2019;15(5):809.
Hunasikatti M. Predictors of obstructive sleep apnea on home sleep apnea test after a negative attended polysomnography: not so fast. J Clin Sleep Med. 2019;15(5):807
Kapur VK, Auckley DH, Susmita C, et al. Clinical practice guideline for diagnostic testing for adult obstructive sleep apnea: an American Academy of Sleep Medicine Clinical Practice Guideline. J Clin Sleep Med. 2017;13(3):479–504. [PubMed Central][PubMed]
Collop NA, Anderson WM, Behlecke B, et al. Clinical guidelines for the use of unattended portable monitors in the diagnosis of obstructive sleep apnea in adult patients. J Clin Sleep Med. 2007;3(7):737–747. [PubMed Central][PubMed]
Prasad B, Usmani S, Steffen AD, et al. Short-term variability in apneahypopnea index during extended home portable monitoring. J Clin Sleep Med. 2016;12(6):855–863. [PubMed Central][PubMed]
Qaseem A, Dallas P, Owens DK, et al. Diagnosis of obstructive sleep apnea in adults: a clinical practice guideline from the American College of Physicians. Ann Intern Med. 2014;161(3):210–220. [PubMed]