Autonomic nervous system dysregulation in children with monosymptomatic nocturnal enuresis.

AIM: To investigate the role of autonomic nervous system in subpopulations of children with enuresis. METHODS: We included 35 children with enuresis, divided in children with (17) and without nocturnal polyuria (18) and 43 healthy controls. For all participants hormones and neurotransmitters were measured. Patients and controls wore a sleep tracker device and children with enuresis underwent a 24 h blood pressure monitoring, nocturnal urine output measurement and uroflowmetry. RESULTS: Children with enuresis had lower than controls copeptin and aldosterone, with the latter being more prominent in patients without nocturnal polyuria. Dopamine was lower in patients without nocturnal polyuria compared with patients with nocturnal polyuria. Children without polyuria experienced episodes only during NREM sleep, whereas in children with polyuria episodes occurred in both REM and NREM sleep. Children with enuresis experienced a non-dipping phenomenon during sleep which was more prominent in the group without polyuria. CONCLUSION: In patients with nocturnal polyuria, nocturnal enuresis is associated with sympathetic hyperactivity which results in pressure polyuria and significantly lower systolic dipping during sleep. On the contrary, in children without nocturnal polyuria, it is mostly associated with bladder overactivity due to parasympathetic overstimulation as demonstrated by the NREM-related enuretic episodes and the lower aldosterone and dopamine levels.

Vitamin D levels in primary care patients: correlations with clinical, seasonal, and quality-of-life parameters.

BACKGROUND: The prevalence of vitamin D deficiency varies across countries and few data exist in the adult population in Greece. OBJECTIVES: To assess vitamin D levels in unselected patients from primary care and to investigate possible correlations with clinical, seasonal, and quality-of-life parameters. METHODS: In this cross-sectional study, 389 consecutive patients were included. They were grouped according to vitamin D status as vitamin D deficient (<20 ng/mL) and vitamin D sufficient groups (≥20 ng/mL). Demographic, Epworth Sleepiness Scale (ESS), Athens Insomnia Scale (AIS), Beck Depression Inventory (BDI), and Fatigue Severity Scale (FSS) scores were measured and compared between groups. RESULTS: Vitamin D deficiency (<20 ng/mL) was observed in 50.4% of the cohort. Female gender (76% vs 66%, P = 0.026), obesity (42% vs 26%, P = 0.005), and hypertension (55% vs 43%, P = 0.023) were higher in the vitamin D deficiency group compared with the group without deficiency. After multiparametric adjustments (for age, gender, obesity, comorbidities, and seasonality), hypertension (odds ratio [OR] = 2.338, 95% confidence interval [CI] = 1.257-4.349, P = 0.007), excessive daytime sleepiness (ESS >10; OR = 3.345, 95% CI = 1.124-9.948, P = 0.029), depressive symptoms (BDI >10; OR = 3.769, 95% CI = 0.984-14.443, P = 0.04), and fatigue (FSS >36; OR = 7.157, 95% CI = 0.855-59.877, P = 0.04) showed significant independent associations with vitamin D deficiency in specific subgroups of patients. CONCLUSION: A large proportion of patients in primary care had vitamin D deficiency, independently associated with hypertension, sleepiness, depressive symptoms, and fatigue. Further research is needed in order to determine the role of vitamin D in these patients.

Vitamin D, also known as the "sunshine vitamin," is an essential nutrient long known for its role in bone health. It is also thought to increase the risk of medical conditions such as cancer and cardiovascular disease. Over recent years, we are witnessing a high percentage of the population with vitamin D deficiency in most European countries; however, few data exist in the adult population in Greece. Based on these findings, we assessed vitamin D levels in patients from primary care and investigated possible correlations with clinical, seasonal, and quality-of-life parameters, including sleepiness, insomnia, and depressive symptoms and fatigue. We found a large proportion of patients in primary care to have vitamin D deficiency, which was associated with hypertension, sleepiness, depressive symptoms, and fatigue based on gender, age, and obesity status of patients. Therefore, vitamin D deficiency should be suspected in specific subgroup of patients. Nevertheless, further research is also needed in order to assess if vitamin D supplementation is likely to have a clinically relevant influence on hypertension and quality-of-life parameters.

Sleep laboratories reopening and COVID-19: a European perspective.

Clinical activities regarding sleep disordered breathing (SDB) have been sharply interrupted during the initial phase of the coronavirus disease 2019 (COVID-19) epidemic throughout Europe. In the past months, activities have gradually restarted, according to epidemiological phase of COVID-19 and national recommendations. The recent increase in cases throughout Europe demands a reconsideration of management strategies of SDB accordingly. Diagnosis of SDB and initiation of treatment pose some specific problems to be addressed to preserve the safety of patients and health personnel. This perspective document by a group of European sleep experts aims to summarise some different approaches followed in Europe and United States, which reflect national recommendations according to the epidemiological phase of the COVID-19 infection. Respiratory sleep medicine is likely to change in the near future, and use of telemedicine will grow to avoid unnecessary risks and continue to provide optimal care to patients. In addition, the document covers paediatric sleep studies and indications for titration of noninvasive ventilation, as well as precautions to be followed by patients who are already on positive airway pressure treatment. A single consensus document developed by the European Respiratory Society and national societies would be desirable to harmonise SDB management throughout Europe.

Impact of temperature on obstructive sleep apnoea in three different climate zones of Europe: Data from the European Sleep Apnoea Database (ESADA).

Recent studies indicate that ambient temperature may modulate obstructive sleep apnoea (OSA) severity. However, study results are contradictory warranting more investigation in this field. We analysed 19,293 patients of the European Sleep Apnoea Database (ESADA) cohort with restriction to the three predominant climate zones according to the Köppen-Geiger climate classification: Cfb (warm temperature, fully humid, warm summer), Csa (warm temperature, summer dry, hot summer), and Dfb (snow, fully humid, warm summer). Average outside temperature values were obtained and several hierarchical regression analyses were performed to investigate the impact of temperature on the apnea-hypopnea index (AHI), oxygen desaturation index (ODI), time of oxygen saturation <90% (T90) and minimum oxygen saturation (MinSpO2 ) after controlling for confounders including age, body mass index, gender, and air conditioning (A/C) use. AHI and ODI increased with higher temperatures with a standardised coefficient beta (ß) of 0.28 for AHI and 0.25 for ODI, while MinSpO2 decreased with a ß of -0.13 (all results p < .001). When adjusting for climate zones, the temperature effect was only significant in Cfb (AHI: ß = 0.11) and Dfb (AHI: ß = 0.08) (Model 1: p < .001). The presence of A/C (3.9% and 69.3% in Cfab and Csa, respectively) demonstrated only a minor increase in the prediction of the variation (Cfb: AHI, R2 +0.003; and Csa: AHI, R2 +0.007; both p < .001). Our present study indicates a limited but consistent influence of environmental temperature on OSA severity and this effect is modulated by climate zones.

Vitamin D deficiency in patients evaluated for obstructive sleep apnea: is it associated with disease severity?

PURPOSE: The aim of the present study was to assess vitamin D levels in a large cohort of OSA patients and to investigate possible correlations with clinical and polysomnographic parameters. METHODS: In this cross-sectional study, 685 consecutive patients underwent type 1 polysomnography (PSG) for OSA diagnosis. They were grouped according to apnea-hypopnea index (AHI) as mild, moderate, and severe. Patients with AHI < 5 served as controls. Demographic, PSG data, and serum levels of vitamin D were measured and compared between groups. RESULTS: OSA was diagnosed in 617 of the patients (90%). Of those, 94 (15%) had mild OSA, 150 (24%) moderate OSA, and 373 (61%) severe OSA. The risk of vitamin D deficiency (< 20 ng/mL) was observed in 38% of the cohort. OSA patients had lower vitamin D levels compared to controls (23 ng/mL vs 26 ng/mL, p = 0.006). The lowest levels of vitamin D [mean 21] (p < 0.001 among all groups) and the higher prevalence for vitamin D deficiency (45%) were observed in severe OSA patients. After multiparametric adjustments for age, gender, obesity, and comorbidities, severe OSA showed significant independent associations with the risk of vitamin D deficiency [OR (95% CI) 2.002 (1.049-3.819), p = 0.035]. CONCLUSIONS: A large proportion of patients referred for OSA evaluation had vitamin D deficiency, which was independently associated with severe OSA. However, further research is needed in order to determine the role of vitamin D in OSA patients.

Evaluation of Obstructive Sleep Apnea in Female Patients in Primary Care: Time for Improvement?

Obstructive sleep apnea (OSA) has historically been regarded as a male disease. However, there are a number of significant gender-related differences in the symptoms, diagnosis, and consequences of OSA, which seems to be more severe in male than in female patients, although this sex difference decreases with increasing age. Female patients with OSA tend to present nonspecific symptoms, such as insomnia, depressive symptoms, fatigue, morning headache, and nightmares, often resulting in underdiagnosis and undertreatment compared to male patients. Understanding these differences in women is essential for early identification and referral of patients for diagnosis and treatment of OSA.

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

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.

Characteristics of Patients with Obstructive Sleep Apnea at High Risk for Cardiovascular Disease.

Background and Objectives: To evaluate the influence of obstructive sleep apnea (OSA)-related symptoms on prevalent cardiovascular disease (CVD) in a large clinical population of patients. Materials and Methods: A total of 2127 patients (mean age 55 years, 24% women) underwent diagnostic polysomnography and were evaluated using the Epworth sleepiness scale (ESS), the Athens Insomnia Scale (AIS), and the Beck Depression Inventory (BDI). We investigated the predictive value of OSA-associated symptoms for prevalent cardiovascular disease, after adjustment for relevant confounding factors including age, obesity, and co-morbidities. Results: Patients with OSA and CVD were older and had a higher Body Mass Index (BMI); the percentage of obese patients was also higher (83% vs. 70%, p < 0001). They also had greater neck, waist, and hip circumferences and a higher waist-to-hip ratio. Excessive daytime sleepiness (ESS ≥ 10) [odds ratio (95% CI) 1.112 (0.708-1.748), p = 0.64], insomnia symptoms (AIS ≥ 6) [odds ratio (95% CI) 0.748 (0.473-1.184), p = 0.21], frequent awakenings [odds ratio (95% CI) 1.599 (1.019-2.508), p = 0.06], and nocturia [odds ratio (95% CI) 1.359 (0.919-2.009), p = 0.124] were not associated with CVD after adjustment for the previous confounders. On the other hand, depressive symptoms (BDI ≥ 10) independently predicted prevalent CVD [odds ratio (95% CI) 1.476 (1.154-1.887), p = 0.002]. Further analysis in subgroups stratified by age, BMI, and gender demonstrated that depressive symptoms predicted prevalent CVD but only in the subgroup of younger (age group < 60 years), obese (BMI group ≥ 30), and male (OR = 1.959, 95% CI = 1.209-3.175, p = 0.006) OSA patients. Conclusions: OSA patients with CVD were more likely to complain of less typical OSA symptoms and depressive symptoms compared to patients without CVD in this large clinical patient cohort, supportingthecomplexity and heterogeneityof OSA.

Carbonic anhydrase, obstructive sleep apnea and hypertension: Effects of intervention.

Whole blood carbonic anhydrase activity (CAa) is increased in patients with obstructive sleep apnea (OSA). Our study investigated the influence of positive airway pressure (PAP) or CA inhibitor acetazolamide (ACT) therapy on CAa, OSA and blood pressure. Thirty-three OSA patients (21 hypertensive, body mass index (BMI) 37 ± 7 kg/m2 and apnea-hypopnea index (AHI) of 47 ± 31 events/hr) were followed-up after PAP treatment (compliance, 4.7 ± 1.5 hr/day; duration, median 6 [IQR 6,6] months) (Cohort A). A second OSA Cohort (B) contained nine hypertensive patients (BMI, 29 ± 4 kg/m2 ; AHI, 39 ± 20 events/hr) with 2-week treatment of ACT, PAP or ACT + PAP in an open crossover study. CAa was assessed at baseline and at the end of each treatment period. In Cohort A, baseline CAa was higher in hypertensive, compared with normotensive, patients (1,033 ± 204 versus 861 ± 201 units, p = .028). PAP treatment reduced systolic/diastolic blood pressure but not CAa (-9 ± 11/-5 ± 7 mmHg and -20 ± 289 units, p < .001, <.001 and .70). In Cohort B, blood pressure was reduced in both ACT-treated groups (-10 ± 10/-5 ± 7 mmHg, p = .043 and .019; and -5 ± 5/-13 ± 13 mmHg, p < .001 and .009). AHI was reduced in both groups: ACT only, -17 ± 9 events/hr p = .001; and ACT + PAP, -39 ± 19 events/hr, p < .001. PAP did not change CAa (p = .98) but activity tended to decrease after ACT with or without PAP (p = .081 and .056). CAa is elevated in hypertensive OSA patients. Long-term PAP reduced blood pressure without affecting CAa. ACT reduced blood pressure and CAa. Increased CAa may constitute a physiological characteristic in OSA, contributing to comorbid hypertension.

On the rise and fall of the apnea-hypopnea index: A historical review and critical appraisal.

The publication of "The Sleep Apnea Syndromes" by Guilleminault et al. in the 1970s hallmarked the discovery of a new disease entity involving serious health consequences. Obstructive sleep apnea was shown to be the most important disorder among the sleep apnea syndromes (SAS). In the course of time, it was found that the prevalence of obstructive sleep apnea reached the proportions of a global epidemic, with a major impact on public health, safety and the economy. Early on, a metric was introduced to gauge the seriousness of obstructive sleep apnea, based on the objective measurement of respiratory events during nocturnal sleep. The apnea index and later on the apnea-hypopnea index, being the total count of overnight respiratory events divided by the total sleep time in hours, were embraced as principle measures to establish the diagnosis of obstructive sleep apnea and to rate its severity. The current review summarises the historical evolution of the apnea-hypopnea index, which has been subject to many changes, and has been criticised for not capturing relevant clinical features of obstructive sleep apnea. In fact, the application of the apnea-hypopnea index as a continuous exposure variable is based on assumptions that it represents a disease state of obstructive sleep apnea and that evocative clinical manifestations are invariably caused by obstructive sleep apnea if the apnea-hypopnea index is above diagnostic threshold. A critical appraisal of the extensive literature shows that both assumptions are invalid. This conclusion prompts a reconsideration of the role of the apnea-hypopnea index as the prime diagnostic metric of clinically relevant obstructive sleep apnea.

Unique sleep-stage transitions determined by obstructive sleep apnea severity, age and gender.

In obstructive sleep apnea, patients' sleep is fragmented leading to excessive daytime sleepiness and co-morbidities like arterial hypertension. However, traditional metrics are not always directly correlated with daytime sleepiness, and the association between traditional sleep quality metrics like sleep duration and arterial hypertension is still ambiguous. In a development cohort, we analysed hypnograms from mild (n = 209), moderate (n = 222) and severe (n = 272) obstructive sleep apnea patients as well as healthy controls (n = 105) from the European Sleep Apnea Database. We assessed sleep by the analysis of two-step transitions depending on obstructive sleep apnea severity and anthropometric factors. Two-step transition patterns were examined for an association to arterial hypertension or daytime sleepiness. We also tested cumulative distributions of wake as well as sleep-states for power-laws (exponent α) and exponential distributions (decay time τ) in dependency on obstructive sleep apnea severity and potential confounders. Independent of obstructive sleep apnea severity and potential confounders, wake-state durations followed a power-law distribution, while sleep-state durations were characterized by an exponential distribution. Sleep-stage transitions are influenced by obstructive sleep apnea severity, age and gender. N2 → N3 → wake transitions were associated with high diastolic blood pressure. We observed higher frequencies of alternating (symmetric) patterns (e.g. N2 → N1 → N2, N2 → wake → N2) in sleepy patients both in the development cohort and in a validation cohort (n = 425). In conclusion, effects of obstructive sleep apnea severity and potential confounders on sleep architecture are small, but transition patterns still link sleep fragmentation directly to obstructive sleep apnea-related clinical outcomes like arterial hypertension and daytime sleepiness.

Does gender matter: sex-specific aspects of symptoms, outcome, and therapy of obstructive sleep apnea.

PURPOSE OF REVIEW: Obstructive sleep apnea (OSA) has historically been considered as a male disease. As a result, female individuals with OSA were often under-diagnosed and under-treated compared with male individuals. However, recent data suggest that several OSA-associated adverse cardiovascular outcomes are more pronounced in women. RECENT FINDINGS: This review provides a summary of the most relevant recent evidence with regard to sex-specific OSA characteristics, including atypical symptoms, greater quality of life impairment and several more pronounced adverse outcomes in female individuals compared with male individuals. It also provides updated evidence on the influence of female gender on under-treatment of OSA with limited evidence supporting gender differences in the effects of OSA treatment. SUMMARY: There is evidence suggesting gender-based differences in the frequency, severity, clinical presentation, and outcomes of OSA. The recognition of these gender differences could improve screening with development of female-specific screening instruments, early diagnosis, and individualized therapeutic plans towards better disease management and its outcomes.

Obstructive sleep apnea in pulmonary fibrosis.

PURPOSE OF REVIEW: In previous years, there was limited research related to the role of sleep in interstitial lung diseases (ILDs). Physicians treating ILD patients tended to focus mainly on the daily disabling symptoms overlooking the possible significant role of coexisting sleep disorders, such as obstructive sleep apnea (OSA). However, recently, there has been a growing interest in OSA in ILDs, as well as OSA effect on sleep, life quality and outcome in these patients with emphasis on idiopathic pulmonary fibrosis (IPF). RECENT FINDINGS: OSA has been recognized as an important, high-prevalence comorbidity for the diagnosis and management of IPF. This publication provides a summary of the most relevant recent evidence with regard to OSA in various ILDs and especially IPF, including prevalence, clinical presentation, complications, screening and diagnosis. It also provides updated evidence on the role of OSA therapy in improving sleep, quality of life and disease outcome. SUMMARY: It is too early to characterize OSA and ILDs association as an 'overlap' syndrome. In depth research is needed, including studies with large numbers of ILDs and IPF patients. The main priority is to increase the awareness among physicians for early diagnosis of OSA in ILDs patients.

Periodic limb movements during sleep and blood pressure changes in sleep apnoea: Data from the European Sleep Apnoea Database.

BACKGROUND AND OBJECTIVE: OSA and PLMS are known to induce acute BP swings during sleep. Our current study aimed to address the independent effect of PLMS on BP in an unselected OSA patient cohort. METHODS: This cross-sectional analysis included 1487 patients (1110 males, no previous hypertension diagnosis or treatment, mean age: 52.5 years, mean BMI: 30.5 kg/m2 ) with significant OSA (defined as AHI ≥ 10) recruited from the European Sleep Apnoea Cohort. Patients underwent overnight PSG. Patients were stratified into two groups: patients with significant PLMS (PLMSI > 25 events/hour of sleep) and patients without significant PLMS (PLMSI < 25 events/hour of sleep). SBP, DBP and PP were the variables of interest. For each of these, a multivariate regression linear model was fitted to evaluate the relationship between PLMS and outcome adjusting for sociodemographic and clinical covariates (gender, age, BMI, AHI, ESS, diabetes, smoking and sleep efficiency). RESULTS: The univariate analysis of SBP showed an increment of BP equal to 4.70 mm Hg (P < 0.001) in patients with significant PLMS compared to patients without significant PLMS. This increment remained significant after implementing a multivariate regression model (2.64 mm Hg, P = 0.044). No significant increment of BP was observed for DBP and PP. CONCLUSION: PLMS is associated with a rise in SBP regardless of AHI, independent of clinical and sociodemographic confounders. A PLMS phenotype may carry an increased risk for cardiovascular disease in OSA patients.

Subjective sleep quality is associated with disease status in COPD patients. The cross-sectional Greek UNLOCK study.

PURPOSE: The association of chronic obstructive pulmonary disease (COPD) severity and related health status with sleep quality remains unclear. We aimed to investigate the association between COPD and sleep quality in the Greek national branch of the UNLOCK cohort. METHODS: A sample of 257 COPD patients enrolled cross-sectionally from primary care in Greece. Sleep quality was assessed by the COPD and Asthma Sleep Impact Scale (CASIS-7 items) questionnaire (higher score indicates worse sleep quality). We tested for associations of sleep impairment with health status (CAT and mMRC scores), exacerbations, hospitalizations, GOLD 2018 ABCD status, inhaler adherence, frailty, and sense of coherence, adjusting for age, gender, smoking status, and comorbidities. RESULTS: The majority of patients reported uncontrolled symptoms (91% with ≥ 10 CAT or 61% with ≥ 2 mMRC). Mean (SD) age was 65 (12.3) with 79% males. CASIS-7 mean (SD) score was 37.7 (12.9). After adjustments, CASIS was significantly associated with worse health status (e.g., CASIS increased with CAT ≥ 10 [ß = 12.53, (95% CI, 6.82, 18.25); p < 0.001], mMRC ≥ 2 [ß = 4.96, (95% CI, 1.56, 8.34); p = 0.004]), COPD severity (CAT-based GOLD BD [ß = 8.88 (95% CI, 2.50, 15.26); p = 0.007]), frailty [ß = 8.85 (95% CI 4.45,13.25); p < 0.001], and sense of coherence [ß = -0.14 (95% CI -0.21, -0.06), p < 001]. When using a CASIS cut-off score of 30 as indicator of sleep impairment, additional to the aforementioned associations, we found increased risk for sleep impairment with ≥ 2 exacerbations/year and poor inhaler adherence (p value < 0.05). CONCLUSIONS: Our study suggests that worse health status and COPD severity are associated with poor sleep quality in COPD patients.

Clinical presentation of patients with suspected obstructive sleep apnea and self-reported physician-diagnosed asthma in the ESADA cohort.

Obstructive sleep apnea (OSA) and asthma are often associated and several studies suggest a bidirectional relationship between asthma and OSA. This study analyzed the characteristics of patients with suspected OSA from the European Sleep Apnea Database according to presence/absence of physician-diagnosed asthma. Cross-sectional data in 16,236 patients (29.1% female) referred for suspected OSA were analyzed according to occurrence of physician-diagnosed asthma for anthropometrics, OSA severity and sleepiness. Sleep structure was assessed in patients studied by polysomnography (i.e. 48% of the sample). The prevalence of physician-diagnosed asthma in the entire cohort was 4.8% (7.9% in women, 3.7% in men, p < 0.0001), and decreased from subjects without OSA to patients with mild-moderate and severe OSA (p = 0.02). Obesity was highly prevalent in asthmatic women, whereas BMI distribution was similar in men with and without physician-diagnosed asthma. Distribution of OSA severity was similar in patients with and without physician-diagnosed asthma, and unaffected by treatment for asthma or gastroesophageal reflux. Asthma was associated with poor sleep quality and sleepiness. Physician-diagnosed asthma was less common in a sleep clinic population than expected from the results of studies in the general population. Obesity appears as the major factor raising suspicion of OSA in asthmatic women, whereas complaints of poor sleep quality were the likely reason for referral in asthmatic men.

Evaluation of Inflammatory Markers in a Large Sample of Obstructive Sleep Apnea Patients without Comorbidities.

Systemic inflammation is important in obstructive sleep apnea (OSA) pathophysiology and its comorbidity. We aimed to assess the levels of inflammatory biomarkers in a large sample of OSA patients and to investigate any correlation between these biomarkers with clinical and polysomnographic (PSG) parameters. This was a cross-sectional study in which 2983 patients who had undergone a polysomnography for OSA diagnosis were recruited. Patients with known comorbidities were excluded. Included patients (n = 1053) were grouped according to apnea-hypopnea index (AHI) as mild, moderate, and severe. Patients with AHI < 5 served as controls. Demographics, PSG data, and levels of high-sensitivity C-reactive protein (hs-CRP), fibrinogen, erythrocyte sedimentation rate (ESR), and uric acid (UA) were measured and compared between groups. A significant difference was found between groups in hs-CRP, fibrinogen, and UA. All biomarkers were independently associated with OSA severity and gender (p < 0.05). Females had increased levels of hs-CRP, fibrinogen, and ESR (p < 0.001) compared to men. In contrast, UA levels were higher in men (p < 0.001). Our results suggest that inflammatory markers significantly increase in patients with OSA without known comorbidities and correlate with OSA severity. These findings may have important implications regarding OSA diagnosis, monitoring, treatment, and prognosis. This trial is registered with ClinicalTrials.gov number NCT03070769.