Impact of the COVID-19 pandemic on diagnosis of sleep apnea: an observational study of a hybrid virtual care clinical pathway.

Since the onset of the coronavirus disease 2019 (COVID-19) pandemic, there has been a reduction in patient uptake of in-person care, likely in part, due to patients' fear of contracting COVID infection. We aimed to examine changes in the proportion of patients assessed in a sleep clinic who subsequently underwent in-lab polysomnography before and during the pandemic. A retrospective study was conducted, comparing the periods September 2018-April 2019 (pre-pandemic) and September 2020-April 2021 (pandemic). Among the patients who were referred to an ambulatory sleep clinic in Toronto, Ontario for assessment of possible sleep apnea, the number of patients who underwent diagnostic PSG within 90 days from the first consultation with a physician was analyzed. Significantly lower number of patients underwent PSG in the pandemic than the pre-pandemic period [122/229 patients (53.3%) vs. 169/208 patients (81.3%), p < 0.001]. Older age and having a consultation in the months of full-blown pandemic, which was defined as month with its average of newly confirmed COVID-19 positive cases in Ontario > 1000 cases/day, were associated with declining PSG in the pandemic period. Among patients who underwent PSG, sleep apnea was found in 114/169 (67.5%) and 85/122 (69.7%) patients in the pre-pandemic and the pandemic period, respectively (p = 0.69). During the pandemic, there was a dramatic reduction in uptake of in-lab PSG. It is very likely that a significant proportion of patients in this cohort had sleep apnea that went undiagnosed with significant implications for health outcomes.