Role of primary care in the follow-up of patients with obstructive sleep apnoea undergoing CPAP treatment: a randomised controlled trial.

OBJECTIVE: To evaluate whether follow-up of patients with obstructive sleep apnoea (OSA) undergoing CPAP treatment could be performed in primary care (PC) settings. DESIGN: Non-inferiority, randomised, prospective controlled study. SETTINGS: Sleep unit (SU) at the University Hospital and in 8 PC units in Lleida, Spain. PARTICIPANTS: Patients with OSA were randomised to be followed up at the SU or PC units over a 6-month period. MAIN OUTCOMES MEASURED: The primary outcome was CPAP compliance at 6 months. The secondary outcomes were Epworth Sleep Scale (ESS) score, EuroQoL, patient satisfaction, body mass index (BMI), blood pressure and cost-effectiveness. RESULTS: We included 101 patients in PC ((mean±SD) apnoea-hypopnoea index (AHI) 50.8±22.9/h, age 56.2±11 years, 74% male) and 109 in the SU (AHI 51.4±24.4/h, age 55.8±11 years, 77% male)). The CPAP compliance was (mean (95% CI) 4.94 (4.47 to 5.5) vs 5.23 (4.79 to 5.66) h, p=0.18) in PC and SU groups, respectively. In the SU group, there were greater improvements in ESS scores (mean change 1.79, 95% CI +0.05 to +3.53, p=0.04) and patient satisfaction (-1.49, 95% CI -2.22 to -0.76); there was a significant mean difference in BMI between the groups (0.57, 95% CI +0.01 to +1.13, p=0.04). In the PC setting, there was a cost saving of 60%, with similar effectiveness, as well as a decrease in systolic blood pressure (-5.32; 95% CI -10.91 to +0.28, p=0.06). CONCLUSIONS: For patients with OSA, treatment provided in a PC setting did not result in worse CPAP compliance compared with a specialist model and was shown to be a cost-effective alternative. TRIAL REGISTRATION NUMBER: Clinical Trials NCT01918449.

Effects of adenotonsillectomy on plasma inflammatory biomarkers in obese children with obstructive sleep apnea: A community-based study.

BACKGROUND: Obesity and obstructive sleep apnea syndrome (OSA) are highly prevalent and frequently overlapping conditions in children that lead to systemic inflammation, the latter being implicated in the various end-organ morbidities associated with these conditions. AIM: To examine the effects of adenotonsillectomy (T&A) on plasma levels of inflammatory markers in obese children with polysomnographically diagnosed OSA who were prospectively recruited from the community. METHODS: Obese children prospectively diagnosed with OSA, underwent T&A and a second overnight polysomnogram (PSG) after surgery. Plasma fasting morning samples obtained after each of the two PSGs were assayed for multiple inflammatory and metabolic markers including interleukin (IL)-6, IL-18, plasminogen activator inhibitor-1 (PAI-1), monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase-9 (MMP-9), adiponectin, apelin C, leptin and osteocrin. RESULTS: Out of 122 potential candidates, 100 obese children with OSA completed the study with only one-third exhibiting normalization of their PSG after T&A (that is, apnea-hypopnea index (AHI) ≤1/hour total sleep time). However, overall significant decreases in MCP-1, PAI-1, MMP-9, IL-18 and IL-6, and increases in adropin and osteocrin plasma concentrations occurred after T&A. Several of the T&A-responsive biomarkers exhibited excellent sensitivity and moderate specificity to predict residual OSA (that is, AHI⩾5/hTST). CONCLUSIONS: A defined subset of systemic inflammatory and metabolic biomarkers is reversibly altered in the context of OSA among community-based obese children, further reinforcing the concept on the interactive pro-inflammatory effects of sleep disorders such as OSA and obesity contributing to downstream end-organ morbidities.

Central sleep apnea is associated with increased risk of ischemic stroke in the elderly.

OBJECTIVES: Sleep apnea/hypopnea syndrome is a well-recognized independent risk factor for stroke in middle-aged population, but controversy remains in older subjects. We examined the possible association between different respiratory parameters and risk of stroke in a prospective population-based cohort of 394 stroke-free elderly subjects. MATERIAL AND METHODS: Fully overnight polysomnography was performed at baseline. Over the 6 year follow-up period, 20 ischemic strokes occurred. Differences in stroke-free survival between subjects according to central apnea index (CAI) were assessed. RESULTS: We just observed association with incident ischemic stroke on central sleep apnea (CSA) episodes. Obstructive sleep apnea, time passed under 90% oxygen saturation, or arousal index were not associated. The event-free survival was lowest in the highest CAI group. This association was independent of any other vascular risk factors. CONCLUSIONS: CSA is the specific respiratory event associated with stroke in the elderly. Additionally, CSA could be a marker of silent brain ischemia, as a sign of disturbed regulation of central respiratory mechanisms, tentatively of ischemic origin.

Early treatment of obstructive apnoea and stroke outcome: a randomised controlled trial.

The aim of the present study was to assess the impact of nasal continuous positive airway pressure (nCPAP) in ischaemic stroke patients followed for 2 yrs. Stroke patients with an apnoea-hypopnoea index ≥ 20 events·h⁻¹ were randomised to early nCPAP (n = 71; 3-6 days after stroke onset) or conventional treatment (n = 69). The Barthel Index, Canadian Scale, Rankin Scale and Short Form-36 were measured at baseline, and at 1, 3, 12 and 24 months. The percentage of patients with neurological improvement 1 month after stroke was significantly higher in the nCPAP group (Rankin scale 90.9 versus 56.3% (p < 0.01); Canadian scale 88.2 versus 72.7% (p < 0.05)). The mean time until the appearance of cardiovascular events was longer in the nCPAP group (14.9 versus 7.9 months; p = 0.044), although cardiovascular event-free survival after 24 months was similar in both groups. The cardiovascular mortality rate was 0% in the nCPAP group and 4.3% in the control group (p = 0.161). Early use of nCPAP seems to accelerate neurological recovery and to delay the appearance of cardiovascular events, although an improvement in patients' survival or quality of life was not shown.

[The availability in Spanish public hospitals of resources for diagnosing and treating sleep apnea-hypopnea syndrome]. / El síndrome de apneas-hipopneas durante el sueño en España. Disponibilidad de recursos para su diagnóstico y tratamiento en los hospitales del Estado español.

INTRODUCTION AND OBJECTIVE: Sleep apnea-hypopnea syndrome is associated with an overall deterioration in the patients health and affects between 1 and 2 million people in Spain. The objective of the present study was to evaluate the diagnostic and therapeutic resources available in Spain for dealing with this problem in terms of both infrastructure and human resources. METHODS: We selected 461 general hospitals, 457 (99.1%) of which answered a questionnaire in the course of a telephone interview. RESULTS: At the time of response, 219 hospitals (47.5%) reported performing sleep studies. Conventional polysomnography was available in 53% of those hospitals, respiratory polygraphy was used in 42%, and oximetry in 5%. In 47% of the hospitals, continuous positive airway pressure was titrated empirically in most cases; the number of patients being treated with CPAP was 109,752, that is, 269 per 100,000 population in Spain. CONCLUSIONS: The level of resources available for diagnosing and treating sleep apnea-hypopnea syndrome, although improving, is clearly still inadequate. Currently, only 0.49 polysomnograph and 0.72 polygraph machines are available per 100,000 population, whereas 1 and 3 machines, respectively, are deemed necessary. Only 5% to 10% of the affected population has been diagnosed, and in 47% of the hospitals interviewed continuous positive airway pressure is not properly titrated. These results should be a clarion call to the health authorities to take the appropriate steps to address this health problem.

[Validation study of a polygraphic screening device (BREAS SC20) in the diagnosis of sleep apnea-hypopnea syndrome]. / Estudio de validez de un equipo de poligrafía respiratoria (BREAS SC-20) para el diagnóstico del síndrome de apneas-hipopneas durante el sueño.

OBJECTIVE: To validate the BREAS SC20 (Breas Medical AB, Mölnlyke, Sweden) polygraphic screening device, comparing it with conventional polysomnography (PSG), in the diagnosis of sleep apnea-hypopnea syndrome. A validity study of the diagnostic test was carried out at the sleep clinic of a tertiary hospital. PATIENTS AND METHODS: Seventy patients clinically suspected of sleep apnea-hypopnea syndrome and treated at the sleep laboratory of the Hospital Txagorritxu, Vitoria, Spain, from November, 2001 until August, 2002 were consecutively enrolled in the study. Patient characteristics, comorbidities, and results on the Epworth sleepiness scale were recorded. The apneahypopnea index (AHI) per hour of sleep was determined by PSG; the respiratory events index (REI) per hour of screening was determined by the polygraphic screening device. RESULTS: Sixty studies were valid (77% were men; mean [SD] age: 51.6 [13.2]; body mass index: 30.3 [5]; AHI: 31.0 [27.6]). The intraclass correlation coefficient between the AHI by PSG and the manual REI was 0.92. The mean difference between the AHI and the manual REI was 2.92 (9.75). The area under the receiver operating characteristic curve was 0.924 for the cut point AHI >or =5. The optimal cut point for an AHI > or = 5 was 3.6 in the REI (98% sensitivity). The respiratory screening device correctly classified 90% to 95% of the patients. CONCLUSIONS: The BREAS SC20 is a valid system for identifying patients clinically suspected of sleep apnea-hypopnea syndrome.

[Validity of a portable recording system (MESAM IV) for the diagnosis of sleep apnea syndrome]. / Validez de un sistema de registro portátil (MESAM IV) para el diagnóstico del síndrome de apnea del sueño.

The development of inexpensive tools for diagnosing sleep apnea syndrome (SAS) is a result of the high prevalence of this condition and of the high cost of polysomnograms (PS). MESAM IV is a portable device that records changes in oxygen saturation (SO2), heart rate (HR) and snoring (S). Readings can be automatic or manual, the latter in function of an events index (EI), with a graph of the three variables generated. We carried out a simultaneous study of 51 subjects suspected of having SAS who were referred to the sleep unit by the pneumology outpatient clinic. PS was interpreted manually at 30-sec intervals as recommended by the American Thoracic Society. An apnea/hypoapnea index (AHI) > or = 10/hour of sleep was used as the cutoff point for SAS. Thirty-two (63%) subjects were found to have SAS as indicated by PS. The rate of agreement between AHI and automatic analysis of SO2, HR and S was only moderate (intra-group correlation coefficients -ICC- of 0.50, 0.40, and 0.53, respectively) and was inferior to manual analysis with EI (ICC of 0.77). Assessment of diagnostic efficacy of automatic analysis in terms of sensitivity (SEN), specificity (SPE), positive predictive value (PPV) and negative predictive value (NPV) yielded the following results: SO2 (SEN 94%, SPE 26%, PPV 68% and NPV 71%), HR (SEN 59%, SPE 58%, PPV 70%, NPV 46%); S (SEN 84%, SPE 26%, PPV 66%, NPV 50%). Manual analysis (EI) gave more valid results (SEN 100%, SPE 84%, PPV 91%, NPV 100%). If patients with chronic obstructive lung disease are excluded, however, the results for automatic analysis improve: SEN 100%, SPE 91%, PPV 96%, NPV 100%. These results show that MESAM IV is of great help in diagnosing SAS, allowing better screening for identifying candidates for PS.

[The prognosis of mediastinal lymph node infiltration (N2) in patients with non-small-cell lung carcinoma (NSCLC) who have undergone curative treatment]. / Pronóstico de la infiltración ganglionar mediastínica (N2) en pacientes con carcinoma de pulmón de células no microcelulares (CPCNM) intervenidos con intenciones curativas.

In this prospective study of 148 surgically treated patients with non-small cell carcinoma of the lung (NSCLC) who were followed for 5 to 7 years, we analyzed the prognostic value of mediastinal lymph node invasion (N2) and survival after 5 years depending on different characteristics. Forty-two (28.4%) patients were N2. Survival in this sample was 9%. Twenty-seven T2N2 patients (among whom survival was 13%) were selected from this group and classified according to whether lymph node invasion was intranodal (survival 39%) or extracapsular (survival 5%) (p < or = 0.05). We also evaluated the prognostic value of different ganglionic areas in accordance to the maps suggested by the American Thoracic Society (ATS). There were no survivors for areas 2, 8 and 9, and no patient with invasion of more than two areas lived more than 18 months. Significant differences in survival were found among patients with invasion of areas 10 and 11. We conclude a) that global analysis of N2 is of such little value in predicting survival that surgery is not justified unless screening criteria are applied; b) that extracapsular invasion rules out surgical treatment; c) that the prognostic value of ganglionic areas is not entirely clear, although the prognosis seems to be poorer for invasion of areas 2, 8 and 9 or invasion of more than 2 areas, and d) that invasion of area 10 would appear to be better classified as N2 than as N1.

[A multivariate prospective study of prognostic factors in non-small-cell lung carcinoma (NSCLC): the results at 5 years]. / Estudio prospectivo multivariante sobre factores pronósticos en el carcinoma de pulmón no microcelular (CPNM): resultados a 5 años.

We present the results of a 5-year prospective study of 153 patients with a diagnosis of bronchogenic carcinoma (BC) who underwent curative surgery. Clinical and anatomical variables were analyzed by multiple regression analysis for prediction of death. Among the anatomical variables, the most significant were the following: stages of anatomical spread (p < or = 0.00000), ganglionic state (p < or = 0.00000), type for surgery (curative or non-curative) (p < or = 0.00000) and state of tumor (p = 0.00012). Significant clinical variables were clinical stage by Feinstein's classification (p = 0.00037), functional capacity (ECOG scale) (p = 0.01196) and tumor size measured conventionally (p = 0.01196). These variables were entered into a multivariate model for prognostic prediction in order to determine the patient's relative risk over time. The best combination of anatomical variables was obtained by associating the stages of spread and ganglionic state (chi 2 = 34.24; p = < 0.00000); the best combination of clinical variables was clinical stage and tumor size (chi 2 = 17.37; p = 0.00023). Thus, although the anatomical variables are more important than clinical ones, the latter have independent prognostic value, are easy to obtain and are available before surgery. They therefore represent an alternative to prognosis based on anatomical spread.

[The role of computed tomography (CT) of the thorax in defining the anatomical extent in bronchogenic carcinoma (BC)]. / Papel de la tomografía computarizada (TC) de tórax en la definición de la extensión anatómica en el carcinoma broncogénico (CB).

A series of 129 carriers of non-small cell bronchogenic carcinoma (BC), in whom computed tomography (CT) of the thorax was performed as part of the preoperative study, are presented. The results of CT were compared with those of thoracotomy in terms of sensitivity (SEN), specificity (SP), positive predictive value (PPV) and negative predictive value (NPV). Thoracic wall (prevalence 0.18): SEN, SP, PPV and NPV were 0.65, 0.92, 0.63 and 0.92, respectively. In peripheral tumors these values were 0.85, 0.90, 0.69 and 0.96, respectively. CT demonstrating invasion of the thoracic wall thus requires confirmation for the purpose of surgical staging. If CT reveals an intact wall, however, surgery may take place immediately. Malignant mediastinal lymph nodes: (prevalence 0.36): SEN, SP, PPV, and NPV were 0.70, 0.89, 0.78 and 0.84, respectively. For peripheral tumors these values were 0.78, 0.93, 0.82 and 0.91, respectively. CT demonstrating malignant mediastinal lymph nodes should be confirmed by mediastinoscopy. If mediastinal malignancy is not observed by CT, thoracotomy may be performed in peripherally located tumors; in centrally located tumors, however, the absence of adenopathy should be confirmed by mediastinoscopy.

[Distribution of pulmonologists and chest surgeons in Spain]. / Distribución de neumólogos y cirujanos torácicos en España.

OBJECTIVE: To study the real situation of respiratory medicine specialists and chest surgeons in the Spanish health service. SUBJECTS AND METHOD: Using the database of the secretary of the Spanish Society of Respiratory Medicine and Chest Surgery (SEPAR) for 1999, we gathered data on 326 Spanish hospitals. We were thus able to ascertain the level of staffing of respiratory medicine and chest surgery departments. The results were expressed as simple percentages showing distribution by age, duties and geographic area. The number of specialists per 100,000 inhabitants in each community was also calculated based on population data provided by the National Statistics Institute for 1997. RESULTS: We studied 1,786 physicians or surgeons (1,245 pneumologists, 185 surgeons and 356 from other specialties). The mean age was 41 9 years for pneumologists, 44 10 years for surgeons and 51 8 years for the others. We observed unequal distribution by geographic area, with a high of 6.66 pneumologists and 0.9 surgeons per 100,000 inhabitants in Asturias and Madrid, respectively and a low of 1.4 pneumologists per 100,000 inhabitants in Murcia and 0 surgeons in Extremadura. CONCLUSIONS: Specialist coverage by pneumologists and chest surgeons is inadequate in many provinces and communities in Spain. The professional market is not saturated, indicating that future specialists can look forward to market demand.

[Measurement of pulmonary function in laryngectomized patients]. / Medición de la función pulmonar en pacientes laringectomizados.

Comparative study upon clinic, radiological and spirometric parameters in 30 laryngectomees, which were spirometric tested by means of a device either simple, cheap, speed and efficient, designed by the AA. These are the conclusions drown out: 1st. There is a poor correlation clinic-functional in patients with obstructive pathology (which command, in the AA's opinion an exploration of the respiratory function in all laryngectomees). 2nd. On the contrary, there are a good radiological and functional correlation in patients suffering for restrictive disease (here the assessment functional means the quantification of the restrictive process). And 3rd. The laryngectomees show a higher functional affectation and can be expected if related to the age and sex. The explanation is to be found in the intercurrent diseases and also in the infections following the larynx removal.

Plasma levels of neuropeptides and metabolic hormones, and sleepiness in obstructive sleep apnea.

BACKGROUND: Obstructive sleep apnea (OSA) is related to obesity and metabolic disorders. The main clinical symptoms are excessive daytime sleepiness (EDS) and snoring. However, not all patients with OSA manifest EDS. Hypocretin-1, neuropeptide Y, leptin, ghrelin and adiponectin are implicated in both metabolic and sleep regulation, two conditions affected by OSA. We hypothesized that levels of these peptides may be related to EDS in OSA patients. METHODS: We included 132 patients with EDS, as defined by an Epworth Sleepiness Scale (ESS) score ≥ 13 (mean ± SD, 15.7 ± 2.3) and 132 patients without EDS as defined by an ESS score ≤ 9 (6.5 ± 1.9). All patients had an apnea-hypopnea index (AHI) ≥ 20 h(-1). Both groups were matched for gender (males; 83.3% vs. 85.6%), age (50.15 ± 11.2 yrs vs. 50.7 ± 9.9 yrs), body mass index (BMI) (31.8 ± 5.6 kg m(-2) vs. 32.1 ± 4.8 kg m(-2)), and apnea-hypopnea index (AHI) (45.5 ± 19.1 h(-1) vs. 43 ± 19.2 h(-1)). RESULTS: OSA patients with EDS showed significantly higher plasma hypocretin-1 levels (p < 0.001) and lower plasma ghrelin levels (p < 0.001) than OSA patients without EDS. There were no statistically significant differences in neuropeptide Y (p = 0.08), leptin (p = 0.07) and adiponectin (p = 0.72) between the two groups. In the multiple linear regression model ESS score was associated with plasma levels of hypocretin-1, ghrelin and total sleep time. CONCLUSION: Our study shows that EDS in patients with OSA is associated with increased circulating hypocretin-1 and decreased circulating ghrelin levels, two peptides involved in the regulation of body weight, energy balance, sympathetic tone and sleep-wake cycle. This relationship is independent of AHI and obesity (two key phenotypic features of OSA).

The cost-effectiveness of nCPAP treatment in patients with moderate-to-severe obstructive sleep apnoea.

The demand for diagnostic and therapeutic services for obstructive sleep apnoea syndrome (OSAS) showed marked growth during the 1990s. This paper analyses the long-term cost-effectiveness of nasal continuous positive airway pressure (nCPAP) treatment in comparison to conventional null treatment. A Markov model was used to represent the natural history of OSAS based upon published evidence. Utility values came from a survey of OSAS patients. Data on health costs were collected from hospitals in the Basque Country, Spain. The incremental cost-effectiveness ratio of nCPAP treatment is <6,000 Euros per quality-adjusted life year. On disaggregated analysis, nCPAP treatment accounts for 86% of incremental costs; 84% of incremental effectiveness is attributable to improved quality of life. Treatment of obstructive sleep apnoea syndrome with nasal continuous positive airway pressure has a cost-effectiveness that is in line with that of other commonly funded treatments such as antihypertensive drugs. The key clinical benefit of nasal continuous positive airway pressure treatment is improvement in the quality of life of patients with obstructive sleep apnoea syndrome. This benefit is also precisely the one for which the evidence base is strongest. The remaining uncertainties concerning the impact of nasal continuous positive airway pressure on long-term mortality have only a relatively small impact on the economics of treatment.