Burden of Comorbidities in Patients with OSAS and COPD-OSAS Overlap Syndrome

Abstract

Background and Objectives: Obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) are usually associated with multi-morbidity. The aim of this study was to retrospectively investigate the prevalence of comorbidities in a cohort of patients with OSAS and COPD-OSAS overlap syndrome (OS) patients and to explore differences between these two groups. Materials and Methods: Included were consecutive OS patients and OSAS patients who had been referred to our sleep laboratory, and were matched in terms of sex, age, BMI, and smoking history. Presence of comorbidities was recorded based on their medical history and after clinical and laboratory examination. Results: The two groups, OS patients (n = 163, AHI > 5/h and FEV1/FVC < 0.7) and OSAS patients (n = 163, AHI > 5/h, and FEV1/FVC > 0.7), did not differ in terms of apnea hypopnea index (p = 0.346), and oxygen desaturation index (p = 0.668). Compared to OSAS patients, OS patients had lower average SpO2 (p = 0.008) and higher sleep time with oxygen saturation <90% (p = 0.002) during sleep, and lower PaO2 (p < 0.001) and higher PaCO2 (p = 0.04) in wakefulness. Arterial hypertension was the most prevalent comorbidity for both OS and OSAS, followed by dyslipidemia, cardiovascular disease (CVD) and diabetes. OS was characterized by a higher prevalence of total comorbidities (median (IQR):2 (1–3) vs. 2 (1–2), p = 0.033), which was due to the higher prevalence of CVD (p = 0.016) than OSAS. No differences were observed in other comorbidities. Conclusions: In OS patients, nocturnal hypoxia and impaired gas exchange in wakefulness are more overt, while a higher burden of CVD is observed among them in comparison to sex-, age- and BMI-matched OSAS patients.

Predictive value of red cell distribution width for overlap syndrome in obstructive sleep apnea

“…Regarding the respiratory analyses of polysomnographic records, patients with OVS in our study were found to have increased ODI and desaturation duration than OSAS alone. This was again compatible with the previous reports (6,23,26), as superimposed obstructive events on baseline hypoxemia are associated with more profound nocturnal oxygen desaturation during sleep in patients with OVS (5,34). On the other side, nocturnal heart rate was found similar between the two groups in the current study, although patients with OVS were demonstrated to have higher sympathetic and lower parasympathetic modulation The ROC curve analysis demonstrated that an RDW value of >13.65 has 78.3% sensitivity and 60% specificity for the prediction of OVS among severe OSAS patients.…”

“…In addition to cyclic intermittent hypoxia, which is a characteristic of OSAS, sustained hypoxemia in coexisting COPD, seems to activate other molecules, such as transcription factors produced via HIF-1 alpha-mediated pathways ( 5 ). This persistent inflammatory exposure seems to contribute to an amplified process of atherosclerosis, along with numerous cardiovascular risks and diseases in overt form, of which the latter is documented to be more pronounced in OVS ( 6 ). In line with this, Papachatzakis et al demonstrated a higher rate of multiple comorbidities (≥4) among patients with OVS, when compared to the ones with OSAS alone (28.95% vs. 10.52%) recently ( 7 ).…”

“…In line with this, Papachatzakis et al demonstrated a higher rate of multiple comorbidities (≥4) among patients with OVS, when compared to the ones with OSAS alone (28.95% vs. 10.52%) recently ( 7 ). A few years later, Voulgaris et al reported a higher prevalence of overt cardiovascular disease (CVD) in the OVS group than in the OSAS alone group (23.9% vs. 13.5%) ( 6 ). Of note, the researchers identified arterial hypertension, diabetes mellitus, and dyslipidemia as the most common comorbidities, except for overt CVD, which was initially excluded from our study due to the methodology.…”

“…Regardless of how the cause-effect relationship works, recognizing OVS as soon as possible in a patient being evaluated for sleep-related breathing disorder is essential; since this subset of patients is subjected to a greater magnitude of hypoxic exposure and systemic inflammation. They are more prone to cardiovascular consequences, facing more comorbidities and all-cause mortality (6)(7)(8), and may benefit from immediate appropriate management.…”

Effect of the Implementation of a Structured Diet Management Plan on the Severity of Obstructive Sleep Apnea: A Systematic Review

“…Established risk factors for OSA are male gender, age over 60 years, obesity, smoking, and family history [ 6 ]. In addition, commonly reported comorbidities of OSA include cardiovascular disease, hypertension, cognitive impairment, and diabetes which are often aggravated by OSA [ 7 ].…”