Does Smoking Affect OSA? What about Smoking Cessation?

Gender differences in the relationship between nicotine exposure and symptoms of depression

BACKGROUND

Tobacco-derived nicotine exposure is linked to depression. However, the associations of nicotine and its metabolites with symptoms of depression, particularly concerning gender differences, remain underexplored.

METHODS

The characteristics and total nicotine equivalents (TNE) of 1001 subjects were determined. The association between the TNE and symptoms of depression, accounting for gender differences, was investigated using generalized linear models and subgroup analyses.

RESULTS

Men exhibited significantly greater levels of the nicotine exposure indicators TNE2, TNE3, TNE6, and TNE7 (P < 0.005). A significantly greater percentage of women (23.45 %) than men (9.81 %) exhibited symptoms of depression (P < 0.0001). In women, the relationship between the TNE and depression was reflected by a U-shaped curve with significant inflection points, particularly for TNE3, TNE6, and TNE7. Furthermore, in women, concentrations above 48.98 nmol/mL for TNE3, 53.70 nmol/mL for TNE6, and 57.54 nmol/mL for TNE7 were associated with 154 %, 145 %, and 138 % increases in the risk of depression, respectively. In contrast, these associations did not reach significance among men.

LIMITATIONS

The cross-sectional design limits the ability to infer causality between nicotine exposure and depressive symptoms. Larger-scale studies are needed to confirm these findings.

CONCLUSIONS

Gender could be a significant factor influencing the relationship between nicotine exposure levels and symptoms of depression. The impact of nicotine exposure on symptoms of depression should be particularly considered among women.

IMPLICATIONS

This study revealed the complex relationship between tobacco-related nicotine exposure and depressive symptoms, with a particular focus on gender differences. Our results revealed a distinct U-shaped correlation between total nicotine equivalents and depression in women, which differed from that in men. These findings emphasize the importance of tailoring clinical approaches to address nicotine exposure and manage depressive symptoms based on gender.

Preserved ratio impaired spirometry and severity of obstructive sleep apnea: An observational cross-sectional study

BACKGROUND AND OBJECTIVE

Lung function abnormality of obstructive sleep apnea (OSA) has not been explored well. Preserved ratio impaired spirometry (PRISm) is known for its association with obesity and cardiovascular morbidity, which are also characteristic features of OSA. This study aims to investigate whether the prevalence of PRISm increases according to apnea-hypopnea index levels among subjects with OSA.

METHODS

Conducted as an observational cross-sectional study, the study included 372 patients ≥40 years of age with definitive diagnoses of OSA and pulmonary function assessment from 2000 to 2004. Study subjects were classified based on OSA severity (mild/moderate versus severe). The prevalence of PRISm was estimated and compared between mild/moderate and severe OSA groups.

RESULTS

The prevalence of PRISm was 9.4 % in study subjects, with a higher prevalence in the severe OSA group than the mild/moderate group (12.9 % and 6.2 %, respectively, P = 0.04). The positive association between severe OSA and PRISm remained robust after multivariable adjustment for age, gender, and obesity (multivariable-adjusted odds ratio 2.29 (95 % confidence intervals 1.08-4.86), P = 0.03).

CONCLUSION

Severe OSA is an independent risk factor for PRISm, highlighting the need for comprehensive management of OSA that addresses the potential risk of PRISm.

Sleep Disordered Breathing and Neurocognitive Disorders

Sleep-disordered breathing (SDB), which includes conditions such as obstructive sleep apnea (OSA) and central sleep apnea (CSA), is an independent risk factor for cerebral small vessel disease (CSVD), stroke, heart failure, arrhythmias, and other cardiovascular disorders. The influence of OSA on brain structure and cognitive function has become an essential focus in the heart-brain axis, given its potential role in developing neurocognitive abnormalities. In this review, we found that OSA plays a significant role in the cardio-neural pathway that leads to the development of cerebral small vessel disease and neurocognitive decline. Although data is still limited on this topic, understanding the critical role of OSA in the heart-brain axis could lead to the utilization of imaging modalities to simultaneously identify early signs of pathology in both organ systems based on the known OSA-driven pathological pathways that result in a disease state in both the cardiovascular and cerebrovascular systems. This narrative review aims to summarize the current link between OSA and neurocognitive disorders, cardio-neural pathophysiology, and the treatment options available for patients with OSA-related neurocognitive disorders.

Differences and Risk Factors of Peripheral Blood Immune Cells in Patients with Obstructive Sleep Apnea

Introduction

Obstructive sleep apnea (OSA) is a respiratory disorder characterized by chronic intermittent hypoxia and fragmented sleep, leading to inflammatory response and oxidative stress. However, the differences in immune inflammatory response in OSA patients with different severity remain unclear.

Purpose

This study aims to examine the differences in peripheral blood immune cells and their risk factors in OSA patients.

Patients and Methods

A total of 277 snoring patients from the Sleep Respiratory Disorder Monitoring Center of Zhongnan Hospital of Wuhan University were recruited in this study. According to the diagnosis and severity criteria of OSA, the included patients were further divided into simple snoring, mild, moderate, and severe groups. Peripheral blood immune cell counts including white blood cells, neutrophils, lymphocytes, monocytes, eosinophils, basophils, red blood cells, platelets, and polysomnography indicators were collected from the patients.

Results

Compared with simple snoring patients, the OSA patients had increased circular monocyte and basophil count levels. In addition, correlation analysis results indicated that monocyte count was positively associated with chronic obstructive pulmonary disease (COPD), smoking, apnea-hypopnea index (AHI), the longest apnea duration, and Oxygen desaturation index (ODI), and negatively correlated with average SpO2 in snoring patients. Finally, multiple linear regression analysis revealed that AHI, COPD, smoking, and maximum heart rate were independent predictors of monocyte count.

Conclusion

OSA patients had a significant increase in their peripheral blood monocyte count. AHI, COPD, smoking, and maximum heart rate were risk factors for increased peripheral blood monocyte count in OSA patients. These findings suggest that peripheral blood monocytes can be considered an inflammatory biomarker of OSA.

Burden of obstructive sleep apnea in patients with lung cancer and its effect on performance status

The association between lung cancer and obstructive sleep apnea has remained a matter of debate for years. Obstructive sleep apnea is thought to increase the incidence of lung cancer due to intermittent hypoxaemia and sleep fragmentation. The aim of this study is to assess the prevalence of obstructive sleep apnea in patients with lung cancer and its effect on those patients' performance status. This is a prevalence study that was conducted at Chest Diseases Department, Alexandria Main University Hospitals. We enrolled 153 patients with lung cancer. All patients underwent cardiorespiratory monitoring using a home sleep-testing device. Performance status was assessed using Karnofsky performance status scale. The study included 120 (78.4%) males and 33 (21.6%) females newly diagnosed with lung cancer. The mean age was 59.98 ± 11.11 years. Obstructive sleep apnea (apnea-hypopnea index ≥ 5) was present in 134 (87.6%) patients. Eighty-five (63.4%) patients had mild obstructive sleep apnea, 39 (29.1%) patients had moderate obstructive sleep apnea, and 10 (7.46%) patients had severe obstructive sleep apnea. Prolonged nocturnal oxygen desaturation as demonstrated by time of oxygen saturation spent below 90% (T90%) during total sleep time > 30% was present in 25 (16.3%) patients. There was a significant difference in the median value of Karnofsky performance status scale between patients with lung cancer and associated obstructive sleep apnea and those without obstructive sleep apnea. In conclusion, obstructive sleep apnea is highly prevalent among patients with lung cancer. Performance status is worse among patients with lung cancer in the presence of obstructive sleep apnea. Screening patients with lung cancer for obstructive sleep apnea is important regardless of the presence of classical symptoms of obstructive sleep apnea.

[Obstructive sleep apnea in cardiology clinical practice. Epidemiology, diagnosis, and treatment. Observational, cross-sectional, retrospective study]

Objective

To determine the clinical-epidemiological characteristics, diagnostic feasibility of home respiratory polygraphy and treatment of patients with suspected obstructive sleep apnea (OSA) at cardiovascular risk.

Methods

An observational, cross-sectional, descriptive study was conducted in patients seen in a cardiology outpatient service with suspected OSA, from January 2015 to December 2019. The information was obtained from medical records, and a descriptive statistical analysis was applied to this information.

Results

138 files were reviewed; only 8% of the home respiratory polygraphs were discarded, because they did not meet the required quality standards. It was demonstrated that 89% suffered from OSA, 60% moderate to severe; in men after 50 years of age. The main cardiovascular risk factors was hypertension (89%). The most prevalent heart disease was hypertension (52%). Cardiovascular pharmacological treatment was improved in 82% of the cases. Cardiac rehabilitation in 30%, noninvasive mechanical ventilation 41%, fixed modality 33%, and self-adjustable 9%, all with telemetry.

Conclusions

The prevalence and severity of OSA is higher in the presence of risk or established cardiovascular disease. In the presence of clinical suspicion, it is feasible to confirm the diagnosis with home respiratory poligrafy due to the level of precision and the lower infrastructure required. Greater involvement of the cardiologist in the diagnosis and treatment of this disorder is necessary due to the significant risk of cardiovascular disease it represents.

Causal relationship between levels of myeloperoxidase and obstructive sleep apnea: a bidirectional two-sample Mendelian randomization study

Background

Several observational studies have investigated the association between myeloperoxidase (MPO) and obstructive sleep apnea (OSA). However, the nature of this relationship remains uncertain due to potential selection and confounding biases. To resolve this, we conducted a bidirectional two-sample Mendelian randomization (MR) study to scrutinize the causal relationship between MPO and OSA.

Methods

Instrumental variables (IVs) for OSA were sourced from the publicly available FinnGen dataset, encompassing 38,998 OSA cases and 336,659 controls. Data on MPO were sourced from a study of 21,758 individuals conducted by the European Bioinformatics Institute (EBI). The primary MR analysis utilized the inverse-variance weighted (IVW) method, with MR-Egger intercept and leave-one-out methods assessing pleiotropy and Cochran's Q test determining heterogeneity.

Results

The IVW analysis indicated a causal relationship between heightened MPO levels and an increased incidence of OSA. Individuals with elevated MPO levels manifested a higher propensity to develop OSA, exhibiting an odds ratio (OR) of 1.075 and a 95% confidence interval (CI) of 1.011-1.143 (p = 0.021). Conversely, the reciprocal analysis unveiled no significant association between OSA and heightened MPO levels (p = 0.643). No directional pleiotropy was identified through the MR-Egger intercept test (p > 0.05).

Conclusion

Our study provides evidence of an association between elevated MPO levels and an increased incidence of OSA. However, OSA does not necessarily lead to elevated MPO levels. When patients present with high MPO levels, screening for OSA may be advisable, considering their clinical characteristics.

Obstructive Sleep Apnea and Smoking Increase the Risk of Cardiovascular Disease: Smoking Cessation Pharmacotherapy

Tobacco smoking has been a recognized risk factor for cardiovascular diseases (CVD). Smoking is a chronic relapsing disease and pharmacotherapy is a main component of smoking cessation. Obstructive sleep apnea (OSA) and smoking both increase the risk of CVD and are associated with significant morbidity and mortality. There are few existing data examining how pharmacological treatment, such as nicotine replacement therapy (NRT), bupropion, and varenicline, affect smokers suffering with OSA and especially their cardiovascular effects. The aim of this review was to evaluate the effects of smoking cessation pharmacotherapy on OSA with a special emphasis on the cardiovascular system. Results: Only small studies have assessed the effect of NRTs on OSA. Nicotine gum administration showed an improvement in respiratory events but with no permanent results. No specific studies were found on the effect of bupropion on OSA, and a limited number evaluated varenicline's effects on sleep and specifically OSA. Varenicline administration in smokers suffering from OSA reduced the obstructive respiratory events, especially during REM. Studies on second-line medication (nortriptyline, clonidine, cytisine) are even more limited. There are still no studies evaluating the cardiovascular effects of smoking cessation medications on OSA patients. Conclusions: Sleep disturbances are common withdrawal effects during smoking cessation but could be also attributed to pharmacotherapy. Smokers should receive personalized treatment during their quitting attempts according to their individual needs and problems, including OSA. Future studies are needed in order to evaluate the efficacy and safety of smoking cessation medications in OSA patients.

Causal analysis between gastro-oesophageal reflux disease and obstructive sleep apnoea

Background

Based on evidence from existing observational research, clarifying the causal relationship between gastro-oesophageal reflux disease (GORD) and obstructive sleep apnoea (OSA) is challenging. Here, Mendelian randomisation, a method based on genetics, was used to provide new evidence for causality.

Methods

Summary statistics from two publicly available genome-wide association studies were used to evaluate the causal relationship between GORD and OSA (the GORD database was used as an exposure variable and the OSA database as an outcome). Inverse variance weighting was used as the main analytical tool in Mendelian randomisation to estimate causal effects. The robustness of the results was evaluated by sensitivity analysis. Possible mediators were evaluated using multivariate Mendelian randomisation.

Results

A statistically significant causal relationship was observed between GORD and OSA (OR 1.597, 95% CI 1.401-1.821, p<0.001), and similar results were observed in weighted median and Mendelian randomisation-Egger regression analyses. No bias was found in the sensitivity analysis of Mendelian randomisation estimation. Multivariate Mendelian randomisation showed that GORD significantly increased the risk of developing OSA, even when the possible mediator was excluded (OR 1.107, 95% CI 1.101-1.212, p<0.001).

Conclusion

Our study confirmed a causal relationship between GORD and OSA and suggests that intervention measures should be taken for patients with GORD to prevent the occurrence of OSA.

The Effect of Cadmium on Sleep Parameters Assessed in Polysomnographic Studies: A Case-Control Study

Cadmium is a heavy metal that accumulates in the body due to environmental and occupational exposure. The main form of environmental exposure to cadmium is related to cigarette smoking. The primary aim of this study was to evaluate the effect of cadmium on numerous sleep parameters with the use of polysomnography. The secondary aim of this study was to investigate if environmental exposure to cadmium is a risk factor for the intensity of sleep bruxism (SB).

METHODS

A total of 44 adults underwent a full night of polysomnographic examination. The polysomnograms were assessed according to guidelines set out by the American Academy of Sleep Medicine (AASM). The concentration of cadmium in the blood and urine was determined spectrophotometrically.

RESULTS

The polysomnographic examination confirmed that cadmium, age, male gender and smoking status are independent risk factors for an increase in the apnea-hypopnea index (AHI). Cadmium alters sleep architecture by favoring sleep fragmentation and decreasing the duration of the rapid eye movement (REM) phase of sleep. However, cadmium exposure is not a risk factor for the development of sleep bruxism.

CONCLUSIONS

In summary, this study demonstrates that cadmium affects sleep architecture and is a risk factor for the development of obstructive sleep apnea; however, it does not affect sleep bruxism.

Association between preserved ratio impaired spirometry and sleep apnea in a Chinese community

OBJECTIVE

This study investigated the association between obstructive sleep apnea (OSA) and preserved ratio impaired spirometry (PRISm) in a community population.

METHODS

Baseline data from a prospective cohort study, the Predictive Value of Combining Inflammatory Biomarkers and Rapid Decline of FEV1 for COPD (PIFCOPD), were used for cross-sectional analysis. Participants aged 40-75 years were recruited from the community and their demographic information and medical history were collected. The STOP-Bang questionnaire (SBQ) was used to assess the risk of OSA. Pulmonary function tests were performed using a portable spirometer (COPD-6) and forced expiratory volume in 1 s (FEV1) and 6 s (FEV6) were measured. Routine blood, biochemical, high-sensitivity C-reactive protein (hs-CRP), and interleukin-6 tests were also performed. The pH of the exhaled breath condensate was determined.

RESULTS

A total of 1183 participants were enrolled, of which 221 with PRISm and 962 with normal lung function. The neck circumference, waist-to-hip ratio, hs-CRP concentration, proportion of males, cigarette exposure, number of current smoker, high risk of OSA, and prevalence of nasal and ocular allergy symptoms were significantly higher in the PRISm group than in the non-PRISm group (p < .05). Logistic regression showed that the risk of OSA (odds ratio, 1.883; 95% confidence interval, 1.245-2.848), waist-to-hip ratio, current smoking, and prevalence of nasal allergy symptoms were independently associated with PRISm after correcting for age and sex.

CONCLUSION

These findings showed that OSA prevalence is independently associated with PRISm prevalence. Further studies should confirm the relationship between systemic inflammation in OSA, localized inflammation of the airways, and impaired lung function.

A Prediction Nomogram for Severe Obstructive Sleep Apnea in Snoring Patients: A Retrospective Study

Purpose

Snoring patients, as a high-risk group for OSA, are prone to the combination of severe OSA and face serious health threats. The aim of our study was to develop and validate a nomogram to predict the occurrence of severe OSA in snorers, in order to improve the diagnosis rate and treatment rate in this population.

Patients and Methods

A training cohort of 464 snoring patients treated at our institution from May 2021 to October 2022 was divided into severe OSA and non-severe OSA groups. Univariate and multivariate logistic regression were used to identify potential predictors of severe OSA, and a nomogram model was constructed. An external hospital cohort of 210 patients was utilized as an external validation cohort to test the model. Area under the receiver operating characteristic curve, calibration curve, and decision curve analyses were used to assess the discriminatory power, calibration, and clinical utility of the nomogram, respectively.

Results

Multivariate logistic regression demonstrated that body mass index, Epworth Sleepiness Scale total score, smoking history, morning dry mouth, dream recall, and hypertension were independent predictors of severe OSA. The area under the curve (AUC) of the nomogram constructed from the above six factors is 0.820 (95% CI: 0.782-0.857). The Hosmer-Lemeshow test showed that the model had a good fit (P = 0.972). Both the calibration curve and decision curve of the nomogram demonstrated the corresponding dominance. Moreover, external validation further confirmed the reliability of the predicted nomograms (AUC=0.805, 95% CI: 0.748-0.862).

Conclusion

A nomogram predicting the occurrence of severe OSA in snoring patients was constructed and validated with external data for the first time, and the findings all confirmed the validity of the model. This may help to improve existing clinical decision making, especially at institutions that do not yet have devices for diagnosing OSA.