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

Long-term cohort study of patients presenting with hypercapnic respiratory failure

OBJECTIVE

We sought to describe the long-term prognosis for a population-based cohort of people with hypercapnic respiratory failure (HRF) and the associations between underlying diagnoses and the risks of death and rehospitalisation.

METHODS

We performed a historical cohort study of all persons with HRF in the Liverpool local government area in New South Wales, Australia, in the 3-year period from 2013 to 2015. Cohort members were identified using arterial blood gas results from Liverpool Hospital demonstrating pH ≤7.45 and PaCO2 >45 mm Hg within 24 hours of presentation. Linked health data were obtained from statewide registries with a minimum follow-up period of 6 years. The primary outcomes were time to death from any cause and the standardised mortality ratio (SMR) which compares the observed to the expected number of deaths in the same population. Secondary outcomes were time to rehospitalisation and the associations between death and/or hospitalisation and underlying diagnoses.

RESULTS

The cohort comprised 590 adults aged between 15 and 101 years. Overall, 415 (70.3%) participants died in the follow-up period. Among those who survived the index admission, the probability of survival at 1, 3 and 5 years was 81%, 59% and 45%, respectively. The overall SMR was 9.2 (95% CI 7.6 to 11.0), indicating a near 10-fold risk of death than otherwise expected for age. Most (91%) survivors experienced rehospitalisation, with median (IQR) time to readmission of 3.9 (1.2-10.6) months. Congestive cardiac failure and neuromuscular disease were associated with an increased risk of death, whereas chronic obstructive pulmonary disease and sleep disordered breathing increased the risk of rehospitalisation.

CONCLUSIONS

HRF is associated with poor survival and high risk of rehospitalisation in the 5 years following an index event. The underlying disease appears to have some influence on overall survival and subsequent hospitalisations.

The economic cost of obstructive sleep apnea: A systematic review

Obstructive sleep apnea (OSA) is a common disease associated with a high prevalence of costly comorbidities and accidents that add to the disease's economic impact. Although more attention has been focused on OSA in recent years, no previous systematic reviews have synthesized findings from existing studies that provide estimates of the economic cost of OSA. This study aims to summarize the findings of existing studies that provide estimates of the cost of OSA. Two bibliographic databases, PubMed and Scopus, were used to identify articles on the costs of OSA. The systematic literature review identified 5,938 publications, of which 31 met the inclusion criteria. According to the results, adjusted for inflation and converted to euros, the annual cost per patient ranged from €236 (the incremental cost of OSA) for New Zealand to €28,267 for the United States. The total annual cost per patient in Europe ranged from €1,669 to €5,186. OSA causes a significant burden on society, and OSA-related costs increase many years before the diagnosis and remain elevated for a long time after the diagnosis. Despite some well-conducted studies, the cost estimates for OSA are uncertain and specific to the context in which the study was conducted.

Association between adherence to continuous positive airway pressure treatment and cost among medicare enrollees

OBJECTIVE

To analyze the cost associated with sleep apnea and effects of continuous positive airway pressure (CPAP) treatment on costs among fee-for-service Medicare beneficiaries.

METHODS

Retrospective cohort design using 5% Medicare claims between 2006 and 2010. Medicare beneficiaries with and without sleep apnea diagnosis between 2007 and 2008 were identified and followed retrospectively for 2 years pre-index-date and 2 years post-index-date. We defined CPAP fill as at least one durable medical equipment claim for CPAP in 6-month period. At least three CPAP fills was defined as "full adherence," and one or two CPAP fills was "partial adherence." We used interrupted time series and generalized linear log-link models to study the association between sleep apnea, CPAP treatment, and costs. To minimize bias, we used propensity score and instrumental variables approach.

RESULTS

Sleep apnea was associated with higher costs (odds ratio [OR] = 1.60; 95% confidence interval [CI] = 1.58, 1.63) compared to those without sleep apnea. Almost half of those with sleep apnea received CPAP treatment. Interrupted time series analysis indicated post level increase in mean monthly cost for full CPAP adherence group, partial CPAP adherence group and no-CPAP group. However, the increase was smallest for the full CPAP adherence group. Full CPAP adherence was associated with lower change in cost (OR = 0.92; 95% CI = 0.88, 0.97) compared to the no-CPAP group.

CONCLUSIONS

Medicare beneficiaries with sleep apnea experience increased cost. Full adherence to CPAP treatment for sleep apnea was associated with lower increase in cost. These findings emphasize the need to effectively identify and treat sleep apnea in Medicare patients.

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.

Tratamiento del síndrome de apnea-hipopnea obstructiva del sueño (SAHOS) con presión positiva en la vía aérea (PAP)

Para el tratamiento de cualquier enfermedad es necesario un adecuado manejo multidisciplinar e involucrar al paciente en la mejor opción que se requiera a largo plazo; la falta de tratamiento de los pacientes implica una enorme carga para el sistema sanitario y la sociedad. En la actualidad, existen diferentes tratamientos para los pacientes con síndrome de apnea-hipopnea obstructiva del sueño (SAHOS); el de mayor elección, después de descartar anomalías anatómicas susceptibles de cirugía, es el PAP (presión positiva en vía aérea). Las indicaciones para terapia con PAP incluyen pacientes con índice de apnea-hipopnea (IAH) ≥15 eventos/hora o ≥5 y ≤14 eventos/hora y quejas de somnolencia diurna excesiva, deterioro cognitivo, trastorno del afecto o insomnio, hipertensión arterial documentada, enfermedad arterial coronaria o historia de evento cerebrovascular. Es importante recordar que el IAH debe basarse en sueño ≥2 horas de registro polisomnográfico. Hay diferentes modalidades de tratamiento con PAP y se debe intervenir para buscar mejorar la adherencia al dispositivo, principal limitante para alcanzar la eficacia en el tratamiento. El impacto del tratamiento del SAHOS ha sido investigado, pero la mayoría de los estudios reportados son de carácter observacional.