Cardiopulmonary Coupling in World Trade Center (WTC) Responders and a Sleep Clinic Population
Authors List
Anna E Mullins1, Sri Saranya Ravi1, Ankit Parekh1, Korey Kam1, Thomas M. Tolbert1, Kathleen Black3, Rafael E. de la Hoz4, Robert J Thomas5, Hugi Hilmisson6, Andrew W. Varga1, David M. Rapoport1, Jag Sunderram7, Indu Ayappa1
1 Division of Pulmonary, Critical Care & Sleep Medicine, Icahn School of Medicine at Mount Sinai, New York, USA; 2 Rutgers Environmental & Occupational Health Sciences Institute, New Brunswick, NJ, USA; 3 Rutgers School of Public Health. Piscataway, NJ, USA; 4 Environmental Medicine & Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA; 5 Division of Pulmonary &Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA. 6 MyCardio LLC; 7 Division of Pulmonary,
Critical Care & Sleep Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick. NJ, USA.
Rationale
World Trade Center Responders (WTC-Responders) report significantly more chronic rhinosinusitis (CRS) symptoms compared to sleep clinic populations, and CRS, but not obstructive sleep apnea (OSA), is in turn a significant risk factor for poor sleep quality and insomnia symptoms. We investigated whether greater CRS in WTC-Responders results in less objectively assessed sleep stability compared to a demographically similar sleep clinic population using cardiopulmonary coupling (CPC).
Methods
In-lab polysomnographic (PSG) data from 97 WTC-Resp and 96 age-, sex- and OSA severity (AHI4)- matched clinic controls were exported to European Data Format (EDF) for CPC analysis using the photoplethysmogram (PPG) signal. Sleepiness was measured using the Epworth Sleepiness Scale (ESS) and CRS presence (CRS+) was defined as ≥ 3 out of 7 symptoms. We compared CPC sleep stability (%), sleepiness, and Sleep Quality Indices (SQI), as well as PSG and other variables between WTC-Responders and clinic controls using Wilcoxon rank sum, t-tests and Chi-squared tests where appropriate.
Results
Mean age was 56 years and 83% were male. Median (interquartile range (IQR)) body mass index (BMI) was 30 (6.2) kg/m2. There were no differences in BMI, sleepiness, total sleep time, sleep efficiency or CPC SQI between WTC-Responders and clinic controls. WTC-Responders were significantly more CRS+ compared to clinic controls (53% vs. 25%, p=0.00001) and had significantly more stable sleep (46% vs 38%, p=0.01) (figure 1). WTC-Resp had a significantly lower arousal index (21.4 vs 35.7/hour, p<0.00001), had less severe OSA according to the AHI3A hypopnea criteria (18.7 vs 25.1/hour, p<0.01), and spent significantly less time in bed whilst in the lab compared to clinic controls (444 vs 460 minutes, p=0.02). Among WTC-Responders,
those who were CRS+ were significantly younger and sleepier but were not significantly different according to any CPC or PSG measure investigated (table 1).
Conclusion
Contrary to our expectations, WTC-Responders had greater sleep stability compared to a demographically similar clinic population, despite more prevalent CRS. This is likely due to the greater OSA-related sleep fragmentation observed in the clinic controls despite matching for OSA severity using the AHI4 hypopnea criteria. The observation of greater sleepiness in WTC-Responders with CRS in the absence of objective deficits in sleep suggests subjective perceptions of habitual sleep are not captured during a single night of in-lab PSG.
Anna E Mullins1, Sri Saranya Ravi1, Ankit Parekh1, Korey Kam1, Thomas M. Tolbert1, Kathleen Black3, Rafael E. de la Hoz4, Robert J Thomas5, Hugi Hilmisson6, Andrew W. Varga1, David M. Rapoport1, Jag Sunderram7, Indu Ayappa1
1 Division of Pulmonary, Critical Care & Sleep Medicine, Icahn School of Medicine at Mount Sinai, New York, USA; 2 Rutgers Environmental & Occupational Health Sciences Institute, New Brunswick, NJ, USA; 3 Rutgers School of Public Health. Piscataway, NJ, USA; 4 Environmental Medicine & Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA; 5 Division of Pulmonary &Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA. 6 MyCardio LLC; 7 Division of Pulmonary,
Critical Care & Sleep Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick. NJ, USA.
Rationale
World Trade Center Responders (WTC-Responders) report significantly more chronic rhinosinusitis (CRS) symptoms compared to sleep clinic populations, and CRS, but not obstructive sleep apnea (OSA), is in turn a significant risk factor for poor sleep quality and insomnia symptoms. We investigated whether greater CRS in WTC-Responders results in less objectively assessed sleep stability compared to a demographically similar sleep clinic population using cardiopulmonary coupling (CPC).
Methods
In-lab polysomnographic (PSG) data from 97 WTC-Resp and 96 age-, sex- and OSA severity (AHI4)- matched clinic controls were exported to European Data Format (EDF) for CPC analysis using the photoplethysmogram (PPG) signal. Sleepiness was measured using the Epworth Sleepiness Scale (ESS) and CRS presence (CRS+) was defined as ≥ 3 out of 7 symptoms. We compared CPC sleep stability (%), sleepiness, and Sleep Quality Indices (SQI), as well as PSG and other variables between WTC-Responders and clinic controls using Wilcoxon rank sum, t-tests and Chi-squared tests where appropriate.
Results
Mean age was 56 years and 83% were male. Median (interquartile range (IQR)) body mass index (BMI) was 30 (6.2) kg/m2. There were no differences in BMI, sleepiness, total sleep time, sleep efficiency or CPC SQI between WTC-Responders and clinic controls. WTC-Responders were significantly more CRS+ compared to clinic controls (53% vs. 25%, p=0.00001) and had significantly more stable sleep (46% vs 38%, p=0.01) (figure 1). WTC-Resp had a significantly lower arousal index (21.4 vs 35.7/hour, p<0.00001), had less severe OSA according to the AHI3A hypopnea criteria (18.7 vs 25.1/hour, p<0.01), and spent significantly less time in bed whilst in the lab compared to clinic controls (444 vs 460 minutes, p=0.02). Among WTC-Responders,
those who were CRS+ were significantly younger and sleepier but were not significantly different according to any CPC or PSG measure investigated (table 1).
Conclusion
Contrary to our expectations, WTC-Responders had greater sleep stability compared to a demographically similar clinic population, despite more prevalent CRS. This is likely due to the greater OSA-related sleep fragmentation observed in the clinic controls despite matching for OSA severity using the AHI4 hypopnea criteria. The observation of greater sleepiness in WTC-Responders with CRS in the absence of objective deficits in sleep suggests subjective perceptions of habitual sleep are not captured during a single night of in-lab PSG.
