Medication adherence and persistence in severe obstructive sleep apnea

Correlation between positive airway pressure and medication adherence: the healthy user effect

STUDY OBJECTIVES

Despite the efficacy of positive airway pressure (PAP) for the treatment of obstructive sleep apnea, adherence remains challenging and negatively affects assessments of effectiveness. It is unclear whether low adherence is due to intolerance of PAP or whether this reflects overall adherence with medical therapy. We sought to correlate PAP use with medication adherence to determine whether poor adherence with PAP was specific to this treatment or represented global compliance with medical therapy.

METHODS

A total of 600 consecutive patients with obstructive sleep apnea were treated with PAP. Objective measures of PAP use were correlated with medication adherence. We included all chronically used medications, defined as medications used daily for at least 90 days prior to PAP initiation. Medication use was verified using an electronic health record. PAP adherence ("regular use") was defined as PAP use for ≥ 4 hours/night on ≥ 70% of nights. Medication adherence was defined as > 70% of pills taken as prescribed.

RESULTS

Complete records were available for 566 patients; 361 (63.8%) used chronic medications. The cohort was primarily men (90.3%, age 44.6 ± 10.2 years) with moderate obstructive sleep apnea (apnea-hypopnea index, 18.1 ± 13.9 events/h). In patients on chronic medications, PAP was used 55.8% of nights and 37.7% were regular users. Patients who were adherent with medications used PAP more hours/night (5.4 vs 4.6, P < .001) and were more likely to have regular PAP use compared with those nonadherent with medications (P = .04).

CONCLUSIONS

Adherence with PAP correlated with adherence to chronic medications. Low PAP adherence may reflect an individual's global adherence to medical care. This association may lead to better identification of patients who benefit from targeted therapy to improve overall health care adherence.

CITATION

Lettieri MJ, Warren WA, Walter RJ, Lettieri CJ. Correlation between positive airway pressure and medication adherence: the healthy user effect. J Clin Sleep Med. 2024;20(7):1087-1092.

Association Between Healthy Behaviors and Health Care Resource Use With Subsequent Positive Airway Pressure Therapy Adherence in OSA

BACKGROUND

The healthy adherer effect has gained increasing attention as potential source of bias in observational studies examining the association of positive airway pressure (PAP) adherence with health outcomes in OSA.

RESEARCH QUESTION

Is adherence to PAP associated with healthy behaviors and health care resource use prior to device prescription?

STUDY DESIGN AND METHODS

Data from the IRSR Pays de la Loire Sleep Cohort were linked to health administrative data to identify proxies of heathy behaviors, including adherence to cardiovascular (CV) drugs (medical possession ratio), cancer screening tests, influenza vaccination, alcohol and smoking consumption, and drowsiness-related road accidents during the 2 years preceding PAP onset in patients with OSA. Multivariable regression analyses were conducted to evaluate the association of heathy behaviors with subsequent PAP adherence. Health care resource use was evaluated according to subsequent PAP adherence.

RESULTS

We included 2,836 patients who had started PAP therapy between 2012 and 2018 (65% of whom were PAP adherent with mean daily use ≥ 4 h/night). Being adherent to CV active drugs (medical possession ratio ≥ 80%) and a person who does not smoke were associated with a higher likelihood of PAP adherence (OR, 1.43; 95% CI, 1.15-1.77 and OR, 1.37; 95% CI, 1.10-1.71, respectively). Patients with no history of drowsiness-related road accidents were more likely to continue PAP (OR, 1.39; 95% CI, 1.04-1.87). Patients who were PAP adherent used less health care resources 2 years before PAP initiation than patients who were nonadherent (mean number of outpatient consultations: 19.0 vs 17.2, P = .003; hospitalization days: 5.7 vs 5.0; P = .04; ED visits: 30.7% vs 24.0%, P = .0002, respectively).

INTERPRETATION

Patients who adhere to PAP therapy for OSA were more health-seeking and used less health care resources prior to device initiation than patients who were nonadherent. Until the healthy adherer effect associated with PAP adherence is better understood, caution is warranted when interpreting the association of PAP adherence with CV health outcomes and health care resource use in nonrandomized cohorts.

Obstructive sleep apnea hypopnea syndrome in ancient traditional Chinese medicine

In western medicine, obstructive sleep apnea hypopnea syndrome (OSAHS) is an increasingly serious public health hazard, which is exacerbated by the obesity epidemic and an aging population. Ancient medical literature of traditional Chinese medicine (TCM) also recorded OSAHS-like symptoms but described the disease from a completely distinct theoretical perspective. The earliest records of snoring in ancient China can be traced back 2500 years. In TCM, the pathogenesis of OSAHS can be attributed mainly to turbid phlegm and blood stasis. Various TCM prescriptions, herbal medicines, and external therapy have also been proposed for the prevention and therapy of OSAHS. Some of these strategies are still used in current clinical practice. This review highlights historical characterizations of OSAHS and the theory of TCM and also explores its therapy in TCM, which may shed light on future OSAHS research. This is the first systematic English review of the role of TCM in the treatment of OSAHS.

Statins Restore Endothelial Protection against Complement Activity in Obstructive Sleep Apnea: A Randomized Clinical Trial

Rationale: Increased cardiovascular risk in obstructive sleep apnea (OSA) persists after continuous positive airway pressure (CPAP) and alternative therapies are needed. Impaired endothelial protection against complement is a cholesterol-dependent process that initiates endothelial inflammation in OSA, which increases cardiovascular risk. Objectives: To investigate directly whether lowering cholesterol improves endothelial protection against complement and its proinflammatory effects in OSA. Methods: Newly diagnosed patients with OSA (n = 87) and OSA-free controls (n = 32) participated. Endothelial cells and blood were collected at baseline, after 4 weeks of CPAP therapy, and again after 4 weeks of 10 mg atorvastatin versus placebo using a randomized, double-blind, parallel-group design. Primary outcome was the proportion of a complement inhibitor, CD59, on the endothelial cell plasma membrane in OSA patients after 4 weeks of statins versus placebo. Secondary outcomes were complement deposition on endothelial cells and circulating levels of its downstream proinflammatory factor, angiopoietin-2, after statins versus placebo. Results: Baseline expression of CD59 was lower, whereas complement deposition on endothelial cells and levels of angiopoietin-2 were greater, in patients with OSA compared with controls. CPAP did not affect expression of CD59 or complement deposition on endothelial cells in patients with OSA, regardless of adherence. Compared with placebo, statins increased expression of endothelial complement protector CD59 and lowered complement deposition in patients with OSA. Good CPAP adherence was associated with increased angiopoietin-2 levels, which was reversed by statins. Conclusions: Statins restore endothelial protection against complement and reduce its downstream proinflammatory effects, suggesting a potential approach to reduce residual cardiovascular risk after CPAP in patients with OSA. Clinical trial registered with www.clinicaltrials.gov (NCT03122639).

Positive Airway Pressure Adherence, Mortality, and Cardiovascular Events in Patients with Sleep Apnea

Rationale: Randomized controlled trials showed no effect of positive airway pressure (PAP) therapy for obstructive sleep apnea (OSA) on cardiovascular (CV) risk. However, patient selection and low PAP adherence preclude the generalization of their data to clinical samples. Objectives: To evaluate the association between hours of PAP use, mortality, and CV morbidity in real-life conditions. Methods: Data from the Pays de la Loire Cohort were linked to health administrative data to identify incident major adverse cardiovascular events (MACEs; a composite outcome of mortality, stroke, and cardiac diseases) in patients with OSA who were prescribed PAP. Cox proportional hazards analyses were conducted to evaluate the association between MACEs and quartiles of average daily PAP use over the study period. Measurements and Main Results: After a median follow-up of 6.6 years, 961 of 5,138 patients experienced MACEs. Considering nonadherent patients (0-4 h/night) as the reference group, adjusted hazard ratios (95% confidence intervals) for MACEs were 0.87 (0.73-1.04) for the 4-6 h/night group, 0.75 (0.62-0.92) for the 6-7 h/night group, and 0.78 (0.65-0.93) for the ⩾7 h/night group (P = 0.0130). Sensitivity analyses using causal inference approaches confirmed the association of PAP use with MACEs. The association was stronger in male patients (P value for interaction = 0.0004), patients without overt CV disease at diagnosis (P < 0.0001), and those belonging to the excessively sleepy symptom subtype (P = 0.060). Conclusions: These real-life clinical data demonstrate a dose-response relationship between PAP adherence and incident MACEs in OSA. Patient support programs may help improve PAP adherence and CV outcomes in patients with OSA.

Impact of Healthcare Non-Take-Up on Adherence to Long-Term Positive Airway Pressure Therapy

Background: The effectiveness of positive airway pressure therapies (PAP) is contingent on treatment adherence. We hypothesized that forgoing healthcare may be a determinant of adherence to PAP therapy.

Research Question: The objectives were: (i) to assess the impact of forgoing healthcare on adherence to PAP in patients with Chronic Respiratory Failure (CRF) and patients with Obstructive Sleep Apnea Syndrome (OSAS); (ii) to compare forgoing healthcare patterns in these two chronic conditions.

Study design and methods: Prospective cohort of patients with OSAS or CRF, treated with PAP therapies at home for at least 12 months. At inclusion, patients were asked to fill-in questionnaires investigating (i) healthcare forgone, (ii) deprivation (EPICES score), (iii) socio-professional and familial status. Characteristics at inclusion were extracted from medical records. PAP adherence was collected from the device's built-in time counters. Multivariable logistic regression models were used to assess the associations between healthcare forgone and the risk of being non-adherent to CPAP treatment.

Results: Among 298 patients included (294 analyzed); 33.7% reported forgoing healthcare. Deprivation (EPICES score > 30) was independently associated with the risk of non-adherence (OR = 3.57, 95%CI [1.12; 11.37]). Forgoing healthcare had an additional effect on the risk of non-adherence among deprived patients (OR = 7.74, 95%CI [2.59; 23.12]). OSAS patients mainly forwent healthcare for financial reasons (49% vs. 12.5% in CRF group), whereas CRF patients forwent healthcare due to lack of mobility (25%, vs. 5.9 % in OSAS group).

Interpretation: Forgoing healthcare contributes to the risk of PAP non-adherence particularly among deprived patients. Measures tailored to tackle forgoing healthcare may improve the overall quality of care in PAP therapies.

Clinical Trial Registration: The study protocol was registered in ClinicalTrials.gov, identifier: NCT03591250.

Prevalence and predictors of medication non-adherence among people living with multimorbidity: a systematic review and meta-analysis

OBJECTIVES

This systematic review aimed to describe medication non-adherence among people living with multimorbidity according to the current literature, and synthesise predictors of non-adherence in this population.

METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses. PubMed, EMBASE, CINAHL and PsycINFO were searched for relevant articles published in English language between January 2009 and April 2019. Quantitative studies reporting medication non-adherence and/or predictors of non-adherence among people with two or more chronic conditions were included in the review. A meta-analysis was conducted with a subgroup of studies that used an inclusive definition of multimorbidity to recruit participants, rather than seeking people with specific conditions. Remaining studies reporting prevalence and predictors of non-adherence were narratively synthesised.

RESULTS

The database search produced 10 998 records and a further 75 were identified through other sources. Following full-text screening, 178 studies were included in the review. The range of reported non-adherence differed by measurement method, at 76.5% for self-report, 69.4% for pharmacy data, and 44.1% for electronic monitoring. A meta-analysis was conducted with eight studies (n=8949) that used an inclusive definition of multimorbidity to recruit participants. The pooled prevalence of non-adherence was 42.6% (95% CI: 34.0 - 51.3%, k=8, I²=97%, p<0.01). The overall range of non-adherence was 7.0%-83.5%. Frequently reported correlates of non-adherence included previous non-adherence and treatment-related beliefs.

CONCLUSIONS

The review identified a heterogeneous literature in terms of conditions studied, and definitions and measures of non-adherence used. Results suggest that future attempts to improve adherence among people with multimorbidity should determine for which conditions individuals require most support. The variable levels of medication non-adherence highlight the need for more attention to be paid by healthcare providers to the impact of multimorbidity on chronic disease self-management.

PROSPERO REGISTRATION NUMBER

CRD42019133849.

Randomized clinical trials of cardiovascular disease in obstructive sleep apnea: understanding and overcoming bias

Three recent randomized control trials (RCTs) found that treatment of obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) did not reduce rates of future cardiovascular events. This article discusses the biases in these RCTs that may explain their negative results, and how to overcome these biases in future studies. First, sample selection bias affected each RCT. The subjects recruited were not patients typically presenting for treatment of OSA. In particular, subjects with excessive sleepiness were excluded due to ethical concerns. As recent data indicate that the excessively sleepy OSA subtype has increased cardiovascular risk, subjects most likely to benefit from treatment were excluded. Second, RCTs had low adherence to therapy. Reported adherence is lower than found clinically, suggesting it is in part related to selection bias. Each RCT showed a CPAP benefit consistent with epidemiological studies when restricting to adherent patients, but was underpowered. Future studies need to include sleepy individuals and maximize adherence. Since it is unethical and impractical to randomize very sleepy subjects to no therapy, alternative designs are required. Observational designs using propensity scores, which are accepted by FDA for studies of medical devices, provide an opportunity. The design needs to ensure covariate balance, including measures assessing healthy user and healthy adherer biases, between regular users of CPAP and non-users. Sensitivity analyses can evaluate the robustness of results to unmeasured confounding, thereby improving confidence in conclusions. Thus, these designs can robustly assess the cardiovascular benefit of CPAP in real-world patients, overcoming biases in RCTs.

Value-based sleep and breathing: health economic aspects of obstructive sleep apnea

Obstructive sleep apnea (OSA) is a common and costly medical condition. Untreated OSA is associated with numerous and well-documented adverse health consequences including depression, diabetes, cardiovascular disease, and premature death. In addition to these health consequences, untreated OSA is also associated with substantial costs borne by patients, payers, the health system, and society at large. Perhaps more importantly, evidence suggests that OSA treatment is associated with positive economic benefit. The purpose of this brief review is to introduce economic aspects of OSA, including the potential economic benefit of OSA treatment.

Chinese Herbs Medicine Huatan Huoxue Prescription for obstructive sleep apnea hypopnea syndrome as complementary therapy: A protocol for a systematic review and meta-analysis

OBJECTIVE

The aim of this systematic review and meta-analysis is to assess effectiveness and safety of Chinese Herbs Medicine Huatan Huoxue Prescription (HTHXP) as complementary therapy in treating bronchiectasis.

METHODS

The following databases will be searched: Embase, Cochrane, PubMed, China National Knowledge Infrastructure, Wan Fang, and VIP database from their inception to April 1, 2020. We performed and completed meta-analysis and methodologic evaluation by Review Manager 5.3.3 and statas 12.0 software. Study selection, data extraction, quality assessment, and assessment of risk bias will be performed by 2 reviewers independently. Odds ratios and correlative 95% confidence intervals will be calculated to present the association between the HTHXP and western medicine treatment using Review Manager version 5.3 when there is sufficient available data.

RESULTS

The results will be disseminated through a peer-reviewed journal publication.

CONCLUSION

These systematic review findings will summarize up-to-date evidence for that HTHXP is more effective and safe as adjunctive treatment for patients with bronchiectasis.

ETHICS AND DISSEMINATION

Ethics approval and patient consent are not required as this study is a systematic review based on published articles.

PROSPERO REGISTRATION NUMBER

INPLASY202050079.

Effect of dapagliflozin on obstructive sleep apnea in patients with type 2 diabetes: a preliminary study

Objective

The aim of this case-control study was to assess the efficacy of dapagliflozin combined with metformin for type-2 diabetes mellitus (T2DM) with obstructive sleep apnea hypopnea syndrome (OSAHS).

Methods

A total of 36 patients with newly-diagnosed T2DM and OSAHS were randomized divided into two groups. Eighteen OSAHS patients with T2DM, who were treated with dapagliflozin and metformin, were assigned as the dapagliflozin group. These patients were given dapagliflozin and metformin for 24 weeks between February 2017 and February 2018. Another 18 OSAHS patients with T2DM, who were treated with glimepiride and metformin for 24 weeks, were assigned as the control group. Fasting plasma glucose (FPG) level, postprandial blood glucose (PPG), hemoglobin A1C (HbA1c), fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), blood lipids, body mass index (BMI), blood pressure, apnea-hypopnea index (AHI), minimum oxygen saturation (LSpO₂), and Epworth Somnolence Scale (ESS) score were measured before and at 24 weeks after the initiation of treatment.

Results

In the dapagliflozin group, triglyceride (TG), systolic pressure (SBP) and diastolic pressure (DBP) significantly decreased following treatment, while high-density lipoprotein cholesterol (HDL-C) significantly increased (P < 0.05). Furthermore, a reduction in AHI, an increase in LSpO₂ and a decrease in ESS score were observed in the dapagliflozin group (P < 0.05), but not in the control group. Moreover, blood glucose, HbA1c, HOMA-IR, and BMI significantly decreased in these two groups, and the decrease was more significant in the dapagliflozin group.

Conclusion

These present results indicate that dapagliflozin can significantly reduce glucose, BMI, blood pressure and AHI, and improve hypoxemia during sleep and excessive daytime sleepiness, which thereby has potential as an effective treatment approach for OSAHS.

What is the remaining status of adaptive servo-ventilation? The results of a real-life multicenter study (OTRLASV-study) : Adaptive servo-ventilation in real-life conditions

BACKGROUNDS

As a consequence of the increased mortality observed in the SERVE-HF study, many questions concerning the safety and rational use of ASV in other indications emerged. The aim of this study was to describe the clinical characteristics of ASV-treated patients in real-life conditions.

METHODS

The OTRLASV-study is a prospective, 5-centre study including patients who underwent ASV-treatment for at least 1 year. Patients were consecutively included in the study during the annual visit imposed for ASV-reimbursement renewal.

RESULTS

177/214 patients were analysed (87.57% male) with a median (IQ25-75) age of 71 (65-77) years, an ASV-treatment duration of 2.88 (1.76-4.96) years, an ASV-usage of 6.52 (5.13-7.65) hours/day, and 54.8% were previously treated via continuous positive airway pressure (CPAP). The median Epworth Scale Score decreased from 10 (6-13.5) to 6 (3-9) (p < 0.001) with ASV-therapy, the apnea-hypopnea-index decreased from 50 (38-62)/h to a residual device index of 1.9 (0.7-3.8)/h (p < 0.001). The majority of patients were classified in a Central-Sleep-Apnea group (CSA; 59.3%), whereas the remaining are divided into an Obstructive-Sleep-Apnea group (OSA; 20.3%) and a Treatment-Emergent-Central-Sleep-Apnea group (TECSA; 20.3%). The Left Ventricular Ejection Fraction (LVEF) was > 45% in 92.7% of patients. Associated comorbidities/etiologies were cardiac in nature for 75.7% of patients (neurological for 12.4%, renal for 4.5%, opioid-treatment for 3.4%). 9.6% had idiopathic central-sleep-apnea. 6.2% of the patients were hospitalized the year preceding the study for cardiological reasons. In the 6 months preceding inclusion, night monitoring (i.e. polygraphy or oximetry during ASV usage) was performed in 34.4% of patients, 25.9% of whom required a subsequent setting change. According to multivariable, logistic regression, the variables that were independently associated with poor adherence (ASV-usage ≤4 h in duration) were TECSA group versus CSA group (p = 0.010), a higher Epworth score (p = 0.019) and lack of a night monitoring in the last 6 months (p < 0.05).

CONCLUSIONS

In real-life conditions, ASV-treatment is often associated with high cardiac comorbidities and high compliance. Future research should assess how regular night monitoring may optimize devices settings and patient management.

TRIAL REGISTRATION

The OTRLASV study is registered on ClinicalTrials.gov (Identifier: NCT02429986 ) on 1 April 2015.

Increased Incidence of Stroke, but Not Coronary Heart Disease, in Elderly Patients With Sleep Apnea

Background and Purpose—

The influence of age on the relationship between obstructive sleep apnea (OSA) and the incidence of hard cardiovascular events remains controversial. We sought to analyze the relationship between OSA and the incidence of stroke and coronary heart disease in a large cohort of elderly patients, as well as to investigate the role of continuous positive airway pressure (CPAP) treatment in these associations.

Methods—

Post hoc analysis of a prospective observational study of consecutive patients ≥65 years studied for OSA suspicion at 2 Spanish University Hospitals. Patients with an apnea-hypopnea index (AHI) <15 were the reference group. OSA was defined by an AHI ≥15 and classified as untreated (CPAP not prescribed or compliance <4 hours/day), mild-moderate (AHI 15–29), untreated severe (AHI ≥30), and CPAP-treated (AHI ≥15 and CPAP compliance ≥4 hours/day).

Results—

859 and 794 elderly patients were included in the stroke and coronary heart disease analyses, respectively. The median (interquartile range) follow-up was 72 (50–88.5) and 71 (51.5–89) months, respectively. Compared with the reference group, the fully adjusted hazard ratios for the incidence of stroke were 3.42 (95% CI, 1.37–8.52), 1.02 (95% CI, 0.41–2.56), and 1.76 (95% CI, 0.62–4.97) for the untreated severe OSA group, CPAP-treated group, and untreated mild-moderate OSA group, respectively. No associations were shown between any of the different OSA groups and coronary heart disease incidence.

Conclusions—

The incidence of stroke, but not coronary heart disease, is increased in elderly patients with untreated severe OSA. Adequate CPAP treatment may reduce this risk.

Effects of Adaptive Servoventilation Therapy for Central Sleep Apnea on Health Care Utilization and Mortality: A Population-Based Study

STUDY OBJECTIVES

Adaptive servoventilation (ASV) is the suggested treatment for many forms of central sleep apnea (CSA). We aimed to evaluate the impact of treating CSA with ASV on health care utilization.

METHODS

In this population-based study using the Rochester Epidemiology Project database, we identified patients over a 9-year period who were diagnosed with CSA (n = 1,237), commenced ASV therapy, and had ≥ 1 month of clinical data before and after ASV initiation. The rates of hospitalizations, emergency department visits (EDV), outpatient visits (OPV) and medications prescribed per year (mean ± standard deviation) in the 2 years pre-ASV and post-ASV initiation were compared.

RESULTS

We found 309 patients (68.0 ± 14.6 years, 80.3% male, apnea-hypopnea index 41.6 ± 26.5 events/h, 78% with cardiovascular comorbidities, 34% with heart failure) who met inclusion criteria; 65% used ASV ≥ 4 h/night on ≥ 70% nights in their first month. The overall 2-year mortality rate was 9.4% and CSA secondary to cardiac cause was a significant risk factor for mortality (hazard ratio 1.81, 95% CI 1.09-3.01, P = .02). Comparing pre-ASV and post-ASV initiation, there was no change in the rate of hospitalization (0.72 ± 1.63 versus 0.79 ± 1.44, P = .46), EDV (1.19 ± 2.18 versus 1.26 ± 2.08, P = .54), OPV (31.59 ± 112.42 versus 13.60 ± 17.36, P = .22), or number of prescribed medications (6.68 ± 2.0 versus 5.31 ± 5.86, P = .06). No differences in these outcomes emerged after accounting for adherence to ASV, CSA subtype and comorbidities via multiple regression analysis (all P > .05).

CONCLUSIONS

Our cohort of patients with CSA was quite ill and the use of ASV was not associated with a change in health care utilization.

Sleep Apnea, the Risk of Developing Heart Failure, and Potential Benefits of Continuous Positive Airway Pressure (CPAP) Therapy

Background

Whether there is an association between sleep apnea (SA) and the risk of developing heart failure (HF) is unclear. Furthermore, it has never been established whether continuous positive airway pressure (CPAP) therapy can prevent development of HF. We aimed to investigate SA patients’ risk of developing HF and the association of CPAP therapy.

Methods and Results

Using nationwide databases, the entire Danish population was followed from 2000 until 2012. patients with SA receiving and not receiving CPAP therapy were identified and compared with the background population. The primary end point was first‐time hospital contact for HF and adjusted incidence rate ratios of HF were calculated using Poisson regression models. Among 4.9 million individuals included, 40 485 developed SA during the study period (median age: 53.4 years, 78.5% men) of whom 45.2% received CPAP therapy. Crude rates of HF were increased in all patients with SA relative to the background population. In the adjusted model, the incidence rate ratios of HF were increased in the untreated SA patients of all ages, compared with the background population. Comparing the CPAP‐treated patients with SA with the untreated patients with SA showed significantly lower incidence rate ratios of HF among older patients.

Conclusions

In this nationwide cohort study, SA not treated with CPAP was associated with an increased risk of HF in patients of all ages. Use of CPAP therapy was associated with a lower risk of incident HF in patients >60 years of age, suggesting a protective effect of CPAP therapy in the elderly.

Effect of sodium glucose cotransporter 2 inhibitors on obstructive sleep apnea in patients with type 2 diabetes

Obstructive sleep apnea syndrome (OSAS) is often associated with metabolic disorders such as obesity and type 2 diabetes and may contribute to cardiovascular events. A novel class of antidiabetic drugs, the sodium glucose cotransporter 2 inhibitors (SGLT2i) reduce body weight (BW), although there is limited data on their impact on OSAS. We therefore evaluated the effect of SGLT2i on OSAS in patients with type 2 diabetes. The presented study was a retrospective design in 18 patients with type 2 diabetes with OSAS (4 males, age range 39-81 yr) administrated a SGLT2i. HbA1c, BW, body mass index (BMI), blood pressure (BP) and apnea hypopnea index (AHI) were evaluated before and after SGLT2i administration. The relationships between the reduction in AHI and the other variables were examined using Pearson correlation analysis. We have got result that SGLT2i reduced AHI from 31.9 ± 18.0 to 18.8 ± 11.5 events per hr (p = 0.003). HbA1c, BW and BMI decreased significantly, whereas BP did not. The Pearson correlation analysis showed a significant relationship between the reduction in AHI and pre-administration of AHI. In conclusion, SGLT2i reduced not only HbA1c, BW and BMI but also AHI significantly and therefore has potential as an effective treatment of OSAS.

Variability of breathing during wakefulness while using CPAP predicts adherence

BACKGROUND AND OBJECTIVE

The standard therapy for obstructive sleep apnoea (OSA) is continuous positive airway pressure (CPAP) therapy. However, long-term adherence remains at ~50% despite improvements in behavioural and educational interventions. Based on prior work, we explored whether regularity of breathing during wakefulness might be a physiologic predictor of CPAP adherence.

METHODS

Of the 117 consecutive patients who were diagnosed with OSA and prescribed CPAP, 79 CPAP naïve patients were enrolled in this prospective study. During CPAP initiation, respiratory signals were collected using respiratory inductance plethysmography while wearing CPAP during wakefulness in a seated position. Breathing regularity was assessed by the coefficient of variation (CV) for breath-by-breath estimated tidal volume (V_T ) and total duration of respiratory cycle (Ttot). In a derivation group (n = 36), we determined the cut-off CV value which predicted poor CPAP adherence at the first month of therapy, and verified the validity of this predetermined cut-off value in the remaining participants (validation group; n = 43).

RESULTS

In the derivation group, the CV for estimated V_T was significantly higher in patients with poor adherence than with good adherence (median (interquartile range): 44.2 (33.4-57.4) vs 26.0 (20.4-33.2), P < 0.001). The CV cut-off value for estimated V_T for poor CPAP adherence was 34.0, according to a receiver-operating characteristic (ROC) curve. In the validation group, the CV value for estimated V_T >34.0 confirmed to be predicting poor CPAP adherence (sensitivity, 0.78; specificity, 0.83).

CONCLUSION

At the initiation of therapy, breathing regularity during wakefulness while wearing CPAP is an objective predictor of short-term CPAP adherence.

Treatment and prevention of inflammatory responses and oxidative stress in patients with obstructive sleep apnea hypopnea syndrome using Chinese herbal medicines

The present study aimed to investigate the therapeutic effects of Chinese herbal medicines for the treatment and prevention of inflammatory responses and oxidative stress in obstructive sleep apnea hypopnea syndrome (OSAHS). A total of 60 patients with OSAHS were randomly divided into two groups (n=30/group): The experimental group, who received the conventional treatment + oral administration of the traditional Chinese herbal formula, Jiawei Di Tan Tang; and the control group, who received the conventional treatment only. OSAHS patients were included in the current study if they presented with snoring and had an apnea-hypopnea index (AHI) of >30 in a polysomnography study, without comorbidities. The therapeutic course lasted 12 weeks in both groups. Alterations to the mean clinical symptom score, Epworth sleepiness scale (ESS) and AHI scores, lowest nocturnal blood oxygen saturation (SaO2) and the serum levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin (IL)-6, tumor necrosis factor (TNF)-α and C-reactive protein (CRP) prior to and following treatment were observed. The mean clinical symptom score was significantly decreased in the experimental group post-treatment compared with the control group (P<0.05). In addition, the clinical symptoms in the experimental group were significantly improved following treatment compared with pre-treatment symptoms (P<0.05). Furthermore, the ESS and AHI scores, lowest nocturnal SaO2 and serum levels of SOD, MDA, IL-6, TNF-α and CRP were significantly improved in the experimental group post-treatment compared with the control group (P<0.05). These parameters in the experimental group were also significantly improved post-treatment compared with those pre-treatment (P<0.05). The results of the present study suggested that oral administration of the traditional Chinese herbal formula Jiawei Di Tan Tang was able to attenuate oxidative stress and inflammatory responses in patients with OSAHS, and thus may relieve their clinical symptoms.

Healthcare Use in Individuals with Obesity and Chronic Hypoxemia Treated for Sleep Disordered Breathing

STUDY OBJECTIVES

To determine if treatment of obstructive sleep apnea (OSA) and obesity hypoventilation syndrome (OHS) among patients with chronic hypoxemia is associated with reduced healthcare utilization.

METHODS

We performed a retrospective cohort study of 129 obese, hypoxemic patients who underwent polysomnography and were prescribed positive airway pressure (PAP) therapy. During a 2-year follow-up period we examined the associations between adherence to PAP therapy and rates of hospitalization, emergency room (ER) visits, and outpatient visits.

RESULTS

Severe OSA and OHS were common, as were hypertension, cardiovascular, and pulmonary disease. Forty-nine percent of patients were adherent with PAP therapy. Compared to patients who were not adherent to PAP therapy, adherent patients had significantly lower rates of all-cause hospitalization (incident rate ratio [IRR]:0.55, 95% CI 0.33, 0.93) after adjustment for age, sex and hospitalisation rates prior to treatment. Adjustment for additional comorbidities attenuated this association (IRR: 0.61, 95% CI 0.35, 1.06). Adherence with PAP therapy was associated with lower odds of frequent hospitalization (odds ratio 0.23, 95% CI 0.07, 0.73). There were no significant differences in the rates of ER or outpatient visits between adherent and non-adherent patients.

CONCLUSIONS

Adherence with PAP treatment in patients with chronic hypoxemia and chronic medical disorders is associated with reduced rates of hospitalization, which has significant benefit both for patients and the healthcare system.

Treatment of Sleep Disordered Breathing Liberates Obese Hypoxemic Patients from Oxygen

Background

Obese hypoxemic patients have a high prevalence of sleep disordered breathing (SDB). It is unclear to what extent treatment of SDB can improve daytime hypoxemia.

Methods

We performed a retrospective cohort study of obese hypoxemic individuals, all of whom underwent polysomnography, arterial blood gas analysis, and subsequent initiation of positive airway pressure (PAP) therapy for SDB. Patients were followed for one year for change in partial pressure of arterial oxygen and the need for supplemental oxygen.

Results

One hundred and seventeen patients were treated with nocturnal PAP and had follow-up available. Adherence to PAP was satisfactory in 60%, and was associated with a significant improvement in daytime hypoxemia and hypercapnea; 56% of these patients were able to discontinue supplemental oxygen. Adherence to PAP therapy and the baseline severity of OSA predicted improvement in hypoxemia, but only adherence to PAP therapy predicted liberation from supplemental oxygen.

Conclusions

The identification and treatment of SDB in obese hypoxemic patients improves daytime hypoxemia. It is important to identify SDB in these patients, since supplemental oxygen can frequently be discontinued following treatment with PAP therapy.

Treatment of OSA reduces the risk of repeat revascularization after percutaneous coronary intervention

BACKGROUND

The impact of OSA treatment with CPAP on percutaneous coronary intervention (PCI) outcomes remains largely unknown.

METHODS

Between 2002 and 2012, we identified 390 patients with OSA who had undergone PCI. OSA was diagnosed through in-laboratory sleep studies and defined by an apnea-hypopnea index ≥ 5 events/h. The cohort was divided into three groups: (1) moderate-severe OSA successfully treated with CPAP (n = 128), (2) untreated moderate-severe OSA (n = 167), and (3) untreated mild OSA (n = 95). Main outcomes included repeat revascularization, major adverse cardiac events (MACEs) (ie, death, nonfatal myocardial infarction, repeat revascularization), and major adverse cardiac or cerebrovascular events (MACCEs). The median follow-up period was 4.8 years (interquartile range, 3.0-7.1).

RESULTS

The untreated moderate-severe OSA group had a higher incidence of repeat revascularization than the treated moderate-severe OSA group (25.1% vs 14.1%, P = .019). There were no differences in mortality (P = .64), MACE (P = .33), and MACCE (P = .76) among the groups. In multivariate analysis adjusted for potential confounders, untreated moderate-severe OSA was associated with increased risk of repeat revascularization (hazard ratio, 2.13; 95% CI, 1.19-3.81; P = .011).

CONCLUSIONS

Untreated moderate-severe OSA was independently associated with a significant increased risk of repeat revascularization after PCI. CPAP treatment reduced this risk.

All-cause mortality from obstructive sleep apnea in male and female patients with and without continuous positive airway pressure treatment: a registry study with 10 years of follow-up

BACKGROUND

More information is needed about the effect on mortality of continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea (OSA), especially in women.

METHODS

We employed a historical cohort study design, using data from 25,389 patients with a diagnosis of OSA selected from the Danish National Patient Registry for the period 1999-2009. We used Cox proportional hazard function to evaluate the all-cause mortality from OSA in middle-aged and elderly males and females who were treated, or not, with CPAP.

RESULTS

Female OSA patients had a lower mortality than males, irrespective of whether they received CPAP treatment. CPAP treatment improved survival, as illustrated by the hazard ratio of 0.62 (P<0.001). This effect was dependent on gender: CPAP had no significant effect on 20- to 39-year-old males and females, but the overall mortality in this age group was small. Survival was increased by CPAP in 40- to 59-year-old and ≥60-year-old males, but no such effect was observed in females. Positive predictors of survival were young age, female gender, higher educational level, and low 3-year prior comorbidity as estimated by the Charlson Comorbidity Index. Negative predictors for survival were male gender, age ≥60 years, no CPAP treatment, prior comorbidity, and low educational level.

CONCLUSION

CPAP therapy is associated with reduced all-cause mortality in middle-aged and elderly males, but no significant effect was found in females.

Effects of obesity on the association between long-term sleep apnea treatment and changes in interleukin-6 levels: the Icelandic Sleep Apnea Cohort

The aim of this study was to evaluate changes in interleukin (IL)-6 and soluble IL-6 receptor levels in obstructive sleep apnea patients and assess the role of positive airway pressure treatment and obesity on these changes. A total of 309 newly diagnosed subjects with sleep apnea from the Icelandic Sleep Apnea Cohort were referred for treatment and reassessed at a 2-year follow-up. Full treatment was defined objectively as use ≥ 4 h day(-1) and ≥ 20 days month(-1). At the 2-year follow-up, there were 177 full users, 44 partial users and 88 non-users. The mean change in biomarker levels from baseline to the 2-year follow-up was assessed in a primary model that included adjustment for baseline biomarker levels, baseline body mass index and change in body mass index, as well as after adjustment for numerous relevant covariates. No significant overall difference in IL-6 level change was found among full, partial and non-users. However, in severely obese patients (body mass index ≥ 35), a significant increase in IL-6 levels during the 2-year period was found in partial and non-users, compared to no change in full users. Results were attenuated in a smaller propensity score matched subsample, although similar trends were observed. No differences were found in soluble IL-6 receptor levels between full users and non-users, after adjustment for confounders. In conclusion, among untreated obese sleep apnea patients, IL-6 levels increase substantially during 2 years, while adherence to positive airway pressure treatment may prevent further increases in this inflammatory biomarker.

Role of sleep apnea and continuous positive airway pressure therapy in the incidence of stroke or coronary heart disease in women

RATIONALE

It is unknown whether obstructive sleep apnea (OSA) may be a risk factor for incident cardiovascular events in women.

OBJECTIVES

We sought to investigate whether OSA increases the incidence of a composite of stroke or coronary heart disease (CHD) in women, and the role of continuous positive airway pressure (CPAP) treatment on this association.

METHODS

This was a prospective, observational study conducted in two Spanish teaching hospitals between 1998 and 2007. Consecutive women referred for suspected OSA and free of previous stroke and CHD were analyzed. Women with an apnea-hypopnea index (AHI) less than 10 comprised the control group, and those with an AHI greater than or equal to 10 were diagnosed with OSA and classified as CPAP-treated (adherence ≥ 4 h/d) or untreated (adherence < 4 h/d or not prescribed). The follow-up ended in December 2010.

MEASUREMENTS AND MAIN RESULTS

A total of 967 women were studied (median follow-up, 6.8 yr; interquartile range, 5.2-8.2). The untreated OSA group showed a greater incidence rate of the composite outcome than the control group (2.19 vs. 0.54 per 100 person-years; P < 0.0005). Compared with the control group, the fully adjusted hazard ratios for the composite outcome incidence were 2.76 (95% confidence interval [CI], 1.35-5.62) for the untreated OSA group, and 0.91 (95% CI, 0.43-1.95) for the CPAP-treated group. When the type of cardiovascular event was separately assessed, untreated OSA showed a stronger association with incident stroke (adjusted hazard ratio, 6.44; 95% CI, 1.46-28.3) than with CHD (adjusted hazard ratio, 1.77; 95% CI, 0.76-4.09).

CONCLUSIONS

In women, untreated OSA is associated with increased incidence of serious cardiovascular outcomes, particularly incident stroke. Adequate CPAP treatment seems to reduce this risk.

Adherence of obstructive sleep apnea syndrome patients to continuous positive airway pressure in a public service✩✩Please cite this article as: Queiroz DLC, Yui MS, Braga AA, Coelho ML, Küpper DS, Sander HH, et al. Adherence of obstructive sleep apnea syndrome patients to continuous positive airway pressure in a public service. Braz J Otorhinolaryngol. 2014;80:126-30.,✩✩✩✩Institution: Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo

Introdução:

Objetivo

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Conclusões

Untreated obstructive sleep apnea and the risk for serious long-term adverse outcomes: a systematic review

BACKGROUND

Reports on the association between obstructive sleep apnea (OSA) and risk of death, cardiovascular (CV) events, diabetes and depression have been inconsistent.

METHODS

We conducted a systematic review of the prognostic value of clinical and polysomnographic (PSG) characteristics of OSA for adverse long-term outcomes of untreated OSA in adult patients. A comprehensive search strategy for prognosis studies, OSA, CV events, mortality, depression and diabetes was developed in collaboration with a medical information specialist. All English language studies, from Jan 1999 to Dec 2011, with longitudinal design in adults with OSA diagnosed by PSG recording, found through Medline, Embase and bibliographies of identified articles, were considered eligible. Quality was assessed using published guidelines.

RESULTS

Among 26 articles, ten evaluated the association of OSA with mortality, 9 with a composite CV outcome, 4 with stroke, 2 with diabetes and 1 with depression. Significant relationships between the apnea-hypopnea index (AHI) and outcomes of interest were reported in 18 studies: seven for all-cause mortality, six for composite CV events, three for stroke, one for diabetes and one for depression. The effect of AHI was attenuated by female gender, older age, absence of daytime sleepiness and higher body mass index. Due to clinical heterogeneity between studies, meta-analyses were not performed.

CONCLUSION

Evidence exists in men for a relationship between OSA and all-cause mortality and a composite CV outcome. Associations between OSA and other outcomes remain uncertain. Among OSA-specific markers, only AHI was a consistent predictor. Other consistent predictors were traditional CV risk factors. Research is required to identify effect modifiers and the predictive ability of various AHI threshold values and hypopnea definitions. An enhanced set of OSA-specific predictors will allow better risk stratification to guide OSA treatment.

Effect of adaptive servoventilation on muscle sympathetic nerve activity in patients with chronic heart failure and central sleep apnea

BACKGROUND

Adaptive servoventilation (ASV) improves cardiac function and sympathetic nerve activity in patients with heart failure (HF). However, the mechanisms underlying these improvements remain obscure.

METHODS AND RESULTS

We compared muscle sympathetic nerve activity (MSNA) and cardiorespiratory polygraphy and echocardiography findings at baseline and at 3.5 ± 0.8 months' follow-up in 32 patients with HF (New York Heart Association functional class II or III; ejection fraction <45%) and central sleep apnea (CSA; apnea-hypopnea index [AHI] ≥15/h) who consented (n = 20; ASV group) or declined (n = 12; non-ASV group) to undergo ASV treatment. Compliance with ASV and changes in AHI were determined from data collected by integral counters in devices and from cardiorespiratory polygraphic findings, respectively. Ejection fraction and MSNA significantly changed in the ASV (both P < .001) but not the non-ASV group. Although changes in AHI and MSNA correlated, the average use of ASV did not. In contrast, changes in AHI and the average use of ASV were independent predictors of changes in ejection fraction (both P < .01).

CONCLUSIONS

ASV decreases MSNA and improves cardiac function in association with suppression of CSA in patients with HF.

Retinal and optic nerve evaluation by optical coherence tomography in adults with obstructive sleep apnea-hypopnea syndrome (OSAHS)

OBJECTIVE

To assess the peripapillary retinal nerve fiber layer (RNFL) thickness, optic nerve head (ONH) morphologic parameters, and macular thickness and volume in patients affected by obstructive sleep apnea-hypopnea syndrome (OSAHS).

METHODS

This prospective, observational case-control study consisted of 96 eyes of 50 OSAHS patients (mean age of 50.9 ± 12.4 years, best-corrected visual acuity ≥ 20/20, refractive error less than 3 spherocylindrical diopters, and intraocular pressure <21 mmHg) who were enrolled and compared with 64 eyes of 33 age-matched controls. Peripapillary RNFL thickness, ONH parameters, macular thickness and volume were measured by optical coherence tomography (OCT).

RESULTS

OSAHS patients showed a significant reduction of the nasal quadrant RNFL thickness (74.7 ± 15.8 μm) compared with those values observed in control patients (81.1 ± 16.6 μm, p=0.047, Student's t-test). No differences in peripapillary RNFL thickness were observed when dividing the OSAHS group in accordance with disease severity. Vertical integrated rim area (VIRA) (0.67 ± 0.41 mm(3) in OSAHS vs 0.55 ± 0.29 mm(3) in controls; p=0.043, Student's t-test), horizontal integrated rim width (HIRW) (1.87 ± 0.31 mm(2) in OSAHS vs 1.8 ± 0.25 mm(2) in controls; p=0.039, Student's t-test) and disc area (2.74 ± 0.62 mm(2) in OSAHS vs 2.48 ± 0.42 mm(2) in controls; p=0.002, Student's t-test) showed significant differences, all of them being higher in the OSAHS group. Severe OSAHS had significant higher disc area (2.8 ± 0.7 mm(2)) than controls (2.5 ± 0.4 mm(2); p=0.016, ANOVA test). Temporal inner macular thickness was significantly higher in mild-moderate OSAHS patients (270 ± 12 μm) than in severe OSAHS patients (260 ± 19 μm; p=0.021, ANOVA test).

CONCLUSIONS

OSAHS patients showed decreased peripapillary nasal RNFL thickness, and increased ONH area and volume parameters when they were evaluated by OCT. These findings suggest that neuronal degeneration might be present in the retina of OSAHS patients, as previously observed in some neurodegenerative disorders.

Comorbidities and survival in obstructive sleep apnoea beyond the age of 50

BACKGROUND

Although mortality risk associated with obstructive sleep apnoea (OSA) tends to disappear from the age of 50, it has been suggested that OSA treatment by continuous positive airway pressure (CPAP) improves survival even in older subjects. Life expectancy of subjects with several diseases is worse if OSA coexists. The objectives of this study were to evaluate the relevance of comorbidities in the relationship between OSA and mortality, and in the effect of CPAP on survival, in subjects ≥ 50 years old.

METHODS

Data from 810 patients studied by polysomnography for suspected OSA between 1991 and 2000 were retrospectively evaluated. In 2009, state of survival and use of CPAP were enquired. Three hundred and thirteen subjects were < 50 and 497 were ≥ 50 years at diagnosis.

RESULTS

Age and comorbidities, but not apnoea/hypopnoea index (AHI) or lowest nocturnal arterial oxygen saturation (Nadir SaO(2)), predicted mortality in the whole sample. Nadir SaO(2) was related to mortality among the younger subjects without comorbidities (P = 0·01), but not among the older subjects. In the older patients with an AHI > 30 CPAP treatment was associated with a better survival only if comorbidities coexisted.

CONCLUSIONS

Unlike in younger subjects, in subjects ≥ 50 years old, comorbidities do not mask an effect of OSA on mortality. Among OSA subjects ≥ 50 years old, comorbidities could separate those who may expect an improvement in survival with CPAP treatment from those who may not. Possibly, after the age of 50, OSA per se does not affect survival, but worsens prognosis of subjects with coexisting diseases.

Association between treated and untreated obstructive sleep apnea and risk of hypertension

CONTEXT

Systemic hypertension is prevalent among patients with obstructive sleep apnea (OSA). Short-term studies indicate that continuous positive airway pressure (CPAP) therapy reduces blood pressure in patients with hypertension and OSA.

OBJECTIVE

To determine whether CPAP therapy is associated with a lower risk of incident hypertension.

DESIGN, SETTING, AND PARTICIPANTS

A prospective cohort study of 1889 participants without hypertension who were referred to a sleep center in Zaragoza, Spain, for nocturnal polysomnography between January 1, 1994, and December 31, 2000. Incident hypertension was documented at annual follow-up visits up to January 1, 2011. Multivariable models adjusted for confounding factors, including change in body mass index from baseline to censored time, were used to calculate hazard ratios (HRs) of incident hypertension in participants without OSA (controls), with untreated OSA, and in those treated with CPAP therapy according to national guidelines.

MAIN OUTCOME MEASURE

Incidence of new-onset hypertension.

RESULTS

During 21,003 person-years of follow-up (median, 12.2 years), 705 cases (37.3%) of incident hypertension were observed. The crude incidence of hypertension per 100 person-years was 2.19 (95% CI, 1.71-2.67) in controls, 3.34 (95% CI, 2.85-3.82) in patients with OSA ineligible for CPAP therapy, 5.84 (95% CI, 4.82-6.86) in patients with OSA who declined CPAP therapy, 5.12 (95% CI, 3.76-6.47) in patients with OSA nonadherent to CPAP therapy, and 3.06 (95% CI, 2.70-3.41) in patients with OSA and treated with CPAP therapy. Compared with controls, the adjusted HRs for incident hypertension were greater among patients with OSA ineligible for CPAP therapy (1.33; 95% CI, 1.01-1.75), among those who declined CPAP therapy (1.96; 95% CI, 1.44-2.66), and among those nonadherent to CPAP therapy (1.78; 95% CI, 1.23-2.58), whereas the HR was lower in patients with OSA who were treated with CPAP therapy (0.71; 95% CI, 0.53-0.94).

CONCLUSION

Compared with participants without OSA, the presence of OSA was associated with increased adjusted risk of incident hypertension; however, treatment with CPAP therapy was associated with a lower risk of hypertension.

Update on sleep and its disorders

Inadequate sleep and sleep disorders have important adverse consequences on multiple systems. This review covers three areas: (a) Genetic determinants of sleep disorders. Common gene variants with small effects have been identified for both restless legs syndrome and narcolepsy with cataplexy. Rare variants with large effects have been found in familial phase advance syndrome and in subjects with short sleep durations. (b) Obstructive sleep apnea (OSA). OSA is an oxidative stress disorder. Prospective cohort studies show an increased risk of cardiovascular events in patients with untreated severe OSA. (c) The impact of sleep disorders on obesity and diabetes. Inadequate sleep results in changes in insulin resistance and in hormone levels leading to increases in appetite. Hence, inadequate sleep is associated with development of obesity. OSA is also an independent risk factor for insulin resistance; treatment of OSA can improve insulin sensitivity.

Treatment experience of people with obstructive sleep apnoea seeking continuous positive airways pressure device provision through community pharmacies – a role for pharmacists?

Objectives

This study aimed to explore the unique experiences of people with obstructive sleep apnoea (OSA) who source their treatment through community pharmacies.

Methods

A qualitative study employing the phenomenological approach was used. In-depth semi-structured interviews with a purposive convenience sample of 20 participants were conducted. Twenty participants were recruited from community pharmacies offering continuous positive airways pressure (CPAP) device provision and a teaching hospital in Sydney, Australia. Interviews were digitally recorded and transcribed verbatim, coded using Nvivo8 software and analysed based on the ‘framework’ method.

Key findings

The quality and delivery of information at diagnosis was reported to have been inappropriate for participants' personal needs. Many barriers emerged in regards to CPAP use, consistent with current literature. Participants' self-reported individual styles, coping practices and health beliefs appeared to be the most influential factors in CPAP uptake and adherence, regardless of mechanical advancements and environmental support. High satisfaction was expressed with CPAP obtainment from pharmacy services listing convenience and good service as notable characteristics.

Conclusions

Community pharmacies have the potential to increase OSA awareness and improve optimal usage of CPAP. Psychosocial based models of adherence intervention could potentially be implemented through CPAP providers, including the community pharmacy, to address some of these factors which impede CPAP adherence.

Predictors of continuous positive airway pressure adherence

Continuous positive airway pressure (CPAP) is the leading treatment for obstructive sleep apnoea (OSA), a prevalent disorder of breathing in sleep strongly associated with obesity. OSA has serious adverse health, social and community effects arising from disturbed breathing, loud snoring, poor quality sleep and cardiovascular sequelae. When used appropriately, CPAP treatment is highly effective in normalising breathing and sleep, improving symptoms and lowering adverse event risk. However, patients do not necessarily accept, tolerate or comply with treatment, with many factors influencing CPAP uptake and longer term use. Although knowledge to address challenges affecting CPAP adherence and CPAP mask and machine technologies continue to improve incrementally, optimising CPAP treatment adherence is an ongoing challenge in sleep medicine.

Factors that influence CPAP adherence: an overview

BACKGROUND

Continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea syndrome (OSAS). Consistent adherence to CPAP improves the patient's longevity and quality of life as well as public safety. However, nonadherence is a significant contributor to the growing burden of untreated OSAS, and is associated with negative consequences for the patient, public safety, and the healthcare system.

OBJECTIVE

The use of CPAP is a classic example of an effective treatment for which adherence is extremely variable. This paper examines a multiplicity of factors that influence CPAP adherence.

FACTORS

These factors are traditionally thought of in terms of patient and equipment variables, but in addition physician, family, healthcare facility, and governmental issues all contribute to CPAP adherence.

DISCUSSION

These factors are reviewed and pragmatic recommendations are made for improving clinical practice.

Outcomes in patients with chronic obstructive pulmonary disease and obstructive sleep apnea: the overlap syndrome

RATIONALE

Patients with chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) (overlap syndrome) are more likely to develop pulmonary hypertension than patients with either condition alone.

OBJECTIVES

To assess the relation of overlap syndrome to mortality and first-time hospitalization because of COPD exacerbation and the effect of continuous positive airway pressure (CPAP) on these major outcomes.

METHODS

We included 228 patients with overlap syndrome treated with CPAP, 213 patients with overlap syndrome not treated with CPAP, and 210 patients with COPD without OSA. All were free of heart failure, myocardial infarction, or stroke. Median follow-up was 9.4 years (range, 3.3-12.7). End points were all-cause mortality and first-time COPD exacerbation leading to hospitalization.

MEASUREMENTS AND MAIN RESULTS

After adjustment for age, sex, body mass index, smoking status, alcohol consumption, comorbidities, severity of COPD, apnea-hypopnea index, and daytime sleepiness, patients with overlap syndrome not treated with CPAP had a higher mortality (relative risk, 1.79; 95% confidence interval, 1.16-2.77) and were more likely to suffer a severe COPD exacerbation leading to hospitalization (relative risk, 1.70; 95% confidence interval, 1.21-2.38) versus the COPD-only group. Patients with overlap syndrome treated with CPAP had no increased risk for either outcome compared with patients with COPD-only.

CONCLUSIONS

The overlap syndrome is associated with an increased risk of death and hospitalization because of COPD exacerbation. CPAP treatment was associated with improved survival and decreased hospitalizations in patients with overlap syndrome.

Adherence to sleep apnea therapy and use of lipid-lowering drugs: a study of the healthy-user effect

BACKGROUND

Evidence that continuous positive airway pressure (CPAP) reduces cardiovascular morbidity comes largely from observational studies. This association may be confounded if CPAP adherents are healthier in ways not measured by investigators. We assessed whether patients adhering to lipid-lowering medications were more adherent to CPAP.

METHODS

This was a retrospective cohort study undertaken at the Philadelphia Veterans Affairs (VA) Medical Center (2005-2006) of consecutive patients on lipid-lowering therapy newly initiating CPAP for obstructive sleep apnea. Adherence to medications dispensed via the VA closed-pharmacy system was measured as the proportion of days covered (>/=80% vs < 80%) in the year prior to CPAP initiation. CPAP adherence was defined as >/= 4 h/d of "mask-on" time, measured electronically daily during the first week of CPAP. We examined the association between medication adherence and CPAP adherence using multivariable logistic regression.

RESULTS

Complete data were available for 117 of 142 (81.5%) subjects. After adjustment for age, race, medical comorbidity, and sleep apnea-related clinical factors, subjects with low medication adherence demonstrated a 40.1% (95% CI, 30.0-51.0) probability of using CPAP >/= 4 h/d compared with 55.2% (95% CI, 46.9-63.1) for subjects with adequate (>/=80%) medication adherence (adjusted for comparison, odds ratio (OR) = 1.8 [95% CI, 1.0-3.3], P = .04). Married patients were more adherent to medications and CPAP; inclusion of this factor reduced to nonsignificance the association of medication and CPAP adherence (OR = 1.6 [95% CI, 0.9-2.8], P = .12).

CONCLUSION

Patients consistently refilling lipid-lowering medications were more adherent to CPAP, suggesting that differences in medication adherence or other health-promoting behaviors should be investigated in future nonrandomized, observational studies linking CPAP adherence and cardiovascular outcomes.