Prevalence of Obstructive Sleep Apnoea Among Patients Admitted for Bariatric Surgery. A Prospective Multicentre Trial

BACKGROUND

Obesity has become one of the greatest public health concerns worldwide and is known to be the most important risk factor for obstructive sleep apnoea (OSA). Prevalence of OSA has increased over the last two decades, but it is estimated that the majority of cases still remain undiagnosed. The aim of this study was to investigate the prevalence of OSA in Finnish bariatric surgery candidates.

METHODS

In this prospective multicentre study, standard overnight cardiorespiratory recording was conducted in 197 consecutive patients from three different hospitals. A sleep questionnaire was also administered. Anthropometric and demographic measurements included age, weight, body mass index (BMI) and waist and neck circumference.

RESULTS

Altogether, 71 % of the patients were diagnosed with OSA. The prevalence was higher in males (90 %) than in females (60 %) (p < 0.001). In OSA patients' group, the mean neck and waist circumference was larger (p < 0.001) and the body weight higher (p < 0.01) than in non-OSA group. When separating patients by gender, a significant difference remained only concerning neck circumference in female patients.

CONCLUSIONS

OSA is very common among bariatric surgery patients, especially in men. Considering this and the increased long-term morbidity and mortality generally related to OSA, a routine screening for OSA seems indicated in bariatric patients, particularly men.

Obstructive sleep apnea: the effect of bariatric surgery after 12 months. A prospective multicenter trial

BACKGROUND

Obstructive sleep apnea (OSA) is a highly prevalent sleep disorder, particularly in bariatric patients. It is known to be tightly linked with metabolic abnormalities and cardiovascular morbidity. Obesity is the most noteworthy individual risk factor for OSA. The aim of this study was to investigate the effect of a laparoscopic Roux-en-Y gastric bypass (LRYGB) on OSA one year after surgery.

METHODS

In this prospective multicenter study standard overnight cardiorespiratory recording was conducted 12 months after bariatric surgery in 132 patients who had OSA in the baseline recording prior to the operation. The main outcome measures were changes in the prevalence of OSA and apnea-hypopnea index (AHI). In addition, the changes in anthropometric and demographic measurements including weight, body mass index (BMI), and waist and neck circumference were evaluated. A sleep symptom questionnaire was administered at baseline and at 12 months.

RESULTS

The prevalence of OSA decreased from 71% at baseline to 44% at 12 months after surgery (p < 0.001). OSA was cured in 45% and cured or improved in 78% of the patients, but moderate or severe OSA still persisted in 20% of the patients after the operation. De novo OSA occurred in eight percent of the patients, and total AHI decreased from 27.8 events/h to 9.9 events/h (p < 0.001).

CONCLUSIONS

LRYGB is effective in treating OSA. However, the findings demonstrate that a postoperative cardiorespiratory recording is needed in order to identify the patients with persistent moderate to severe OSA after the operation.

CLINICAL TRIAL REGISTRATION

ClinalTrials.gov; No.: NCT01080404; URL: www.clinicaltrials.gov.

Validation of a symptom-score questionnaire and long- term results of endoscopic dacryocystorhinostomy

BACKGROUND

Endoscopic dacryocystorhinostomy (EN-DCR) is a commonly used procedure in the treatment of nasolacrimal duct obstruction (NLDO). However, there is no generally accepted disease-specific questionnaire for assessing outcomes.

METHODOLOGY

We conducted a prospective study to initially validate a Nasolacrimal Duct Obstruction Symptom Score questionnaire(NLDO-SS) and to evaluate the long-term success of EN-DCR procedures. Seventy-six patients (86 eyes) were evaluated in follow-up visits at 1-8 years after EN-DCR. The patients completed the NLDO-SS questionnaire twice, first, at home and, second,after receiving information from the otorhinolaryngologist, during the visit. The surgical outcome was considered successful if the irrigation succeeded and if the patient symptoms were relieved as assessed with the NLDO-SS.

RESULTS

The diagnostic accuracy of the NLDO-SS was 84%, sensitivity 82%, specificity 85%, positive predictive value 58%, negative predictive value 95%, odds ratio 26, risk ratio 11 and usefulness index 0.55. Cronbach's alpha was 0.85, and the test-retest reliability coefficient was 0.87. The long-term success rate after EN-DCR was 79%.

CONCLUSION

The NLDO-SS iss a feasible clinical tool in assessing the success of EN-DCR. The success rate was found to decrease EN-DCR at long-term follow-up.

Coronary heart disease mortality in relation to dietary, lifestyle and biochemical risk factors in the countries of the Seven Countries Study: a secondary dataset analysis

BACKGROUND

The present study explored coronary heart disease (CHD) mortality rates in 2011 in countries that participated in the Seven Countries Study (SCS) in relation to several dietary and anthropometric/biochemical risk factors. Special focus was given to Crete and the Ionian Islands.

METHODS

This was a cross-sectional study of secondary analysis of databases using data from the World Health Organization, the Food and Agriculture Organization database and the Greek National Cadaster and Cartography Organization. Geographically weighted regression was applied to identify the high-risk regions in relation to the significant factors.

RESULTS

Crete, the Ionian Islands and Japan had the lowest mortality rates (28.9, 30.1 and 31.2 deaths/100,000 people, respectively) in contrast to Serbia/Montenegro that presented the highest rates (105.1 deaths/100,000 people). Diet, physical inactivity and hypertension were found to be the most significant factors in the model (P < 0.05). Regions of no risk were Crete, Ionian Islands and Japan (exponent B = 0.65; 95% confidence interval = 0.293-0.942; P < 0.001), whereas Serbia/Montenegro and Finland were identified as high-risk areas with a 2.97-fold higher probability for CHD mortality (95% confidence interval = 1.736-4.028; P < 0.001).

CONCLUSIONS

Observed patterns of CHD mortality and related factors may be helpful for appropriate management by health planners when aiming to reduce its prevalence, particularly in high-risk areas.

The impact of pharyngeal fat tissue on the pathogenesis of obstructive sleep apnea

PURPOSE

Obesity is the most important risk factor for obstructive sleep apnea (OSA); however, the exact underlying mechanisms are still not fully understood. The aim of this study was to examine the morphology of upper airways in overweight habitual snorers and in mild OSA patients. Furthermore, the associations between weight loss, parapharyngeal fat pad area and OSA were assessed in a 1-year randomised, controlled follow-up study originally conducted to determine the effects of lifestyle changes with weight reduction as a treatment of OSA.

METHODS

Thirty-six overweight adult patients with mild OSA [apnea-hypopnea index (AHI) 5-15 events/h] and 24 weight-matched habitual snorers (AHI < 5 events/h) were included in the study. All patients underwent nocturnal cardiorespiratory recordings and multislice computed tomography (CT) of parapharyngeal fat pad area, the smallest diameter and area in naso-, oro- and hypopharynx, the smallest diameter and area of the whole pharyngeal airway, the distance from the hyoid bone to the mandibular plane and to cervical tangent as well as the distance between mandibular symphysis and cervical spine. In addition, OSA patients were further randomised to receive either an active 1-year lifestyle intervention with an early weight loss programme or routine lifestyle counselling. After 1 year, the cardiorespiratory recordings and CT scans were repeated.

RESULTS

The pharyngeal fat pad area was significantly larger, and the distance from the hyoid bone to cervical spine was longer in patients with OSA than in habitual snorers (p = 0.002 and p = 0.018, respectively). The multiple regression analysis showed that besides a large pharyngeal fat pad area and a long distance from the cervical spine to hyoid bone, also a short distance from the mandibular symphysis to cervical tangent increased a risk to OSA. During the 1-year follow-up in OSA patients, the pharyngeal fat pad area and AHI decreased significantly in the intervention group (p = 0.003 and p < 0.001, respectively).

CONCLUSIONS

In the early stages of OSA, the pharyngeal fat pad seems to play an important role in the development of disease in overweight patients. Furthermore, weight reduction by lifestyle intervention-based programme reduces both central obesity and pharyngeal fat pads, resulting in an improvement of OSA.

Mortality in middle-aged men with obstructive sleep apnea in Finland

INTRODUCTION

Obstructive sleep apnea (OSA) has been associated with an elevated rate of cardiovascular mortality. However, this issue has not been investigated in patients with elevated proneness to cardiovascular diseases. Our hypothesis was that OSA would have an especially adverse effect on the risk of cardiovascular mortality in Finnish individuals exhibiting elevated proneness for coronary heart diseases.

METHODS

Ambulatory polygraphic recordings from 405 men having suspected OSA were retrospectively analyzed. The patients were categorized regarding sleep disordered breathing into a normal group (apnea hypopnea index (AHI) < 5, n = 104), mild OSA group (5 ≤ AHI < 15, n = 100), and moderate to severe OSA group (AHI ≥ 15, n = 201). In addition, basic anthropometric and health data were collected. In patients who died during the follow-up period (at least 12 years and 10 months), the primary and secondary causes of death were recorded.

RESULTS

After adjustment for age, BMI, and smoking, the patients with moderate to severe OSA suffered significantly (p < 0.05) higher mortality (hazard ratio 3.13) than their counterparts with normal recordings. The overall mortality in the moderate to severe OSA group was 26.4 %, while in the normal group it was 9.7 %. Hazard ratio for cardiovascular mortality was 4.04 in the moderate to severe OSA and 1.87 in the mild OSA group.

CONCLUSIONS

OSA seems to have an especially adverse effect on the cardiovascular mortality of patients with an elevated genetic susceptibility to coronary heart diseases. When considering that all our patients had possibility of continuous positive airway pressure treatment and our reference group consisted of patients suffering from daytime somnolence, the hazard ratio of 4.04 for cardiovascular mortality in patients with moderate to severe disease is disturbingly high.

Total duration of apnea and hypopnea events and average desaturation show significant variation in patients with a similar apnea-hypopnea index

Obstructive sleep apnea (OSA) is commonly diagnosed based on the apnea-hypopnea index (AHI). Presently, novel indices were introduced for sleep apnea severity: total duration of sleep apnea and hypopnea events (TAHD%) and a combined index including duration and severity of the events (TAHD% × average desaturation). Two hundred and sixty-seven subjects were divided based on their AHI into four categories (normal, mild, moderate, severe OSA). In the most severe cases TAHD% exceeded 70% of the recorded time. This is important as excessive TAHD% may increase mortality and cerebro-vascular complications. Moreover, simultaneous increase in duration and frequency of apnea and hypopnea events leads to a paradoxical situation where AHI cannot increase along severity of the disease. Importantly, the combined index including duration and severity of the events showed significant variation between patients with similar apnea-hypopnea indices. To conclude, the present results suggest that the novel parameters could give supplementary information to AHI when diagnosing the severity of OSA.

Effect of weight loss on inflammation in patients with mild obstructive sleep apnea

BACKGROUND AND AIMS

Inflammation may be one mediating mechanism for cardiovascular diseases in obstructive sleep apnea (OSA). However, little is known about subclinical inflammation or the effect of lifestyle intervention on inflammation in early stages of OSA. The aim of this substudy of an existing randomized controlled trial, with post hoc analyses, was to determine the impact of lifestyle changes aimed at weight reduction on inflammatory biomarkers in overweight patients with mild OSA.

METHODS AND RESULTS

Patients were randomized to supervised intensive lifestyle intervention group (N=28) or to control group (N=31), which received routine lifestyle advices. Circulating concentrations of pro- and anti-inflammatory mediators were measured before and after the 1-year intervention. The concentrations of two pro-inflammatory mediators, high-sensitivity C-reactive protein (hsCRP) and interleukin (IL)-6, decreased significantly in both groups. Although the changes in inflammatory biomarkers favored the supervised lifestyle intervention, the only significant reduction observed between the groups was for the anti-inflammatory IL-1 receptor antagonist (IL-1RA). The change in hsCRP was associated with apnea-hypopnea index, and improving night-time oxygen saturation was related to tumor necrosis factor alpha. IL-1RA and IL-6 were associated with insulin metabolism.

CONCLUSION

Weight loss resulted in reductions in concentrations of some pro- and anti-inflammatory mediators in overweight patients with mild OSA, overall favoring the supervised lifestyle intervention. These findings suggest that more intensive treatment of obesity in OSA patients might be well-justified.

Accuracy of automatic analysis of ambulatory recordings of nocturnal breathing disorders is significantly instrumentation dependent

Obstructive sleep apnoea (OSA) is generally diagnosed with ambulatory recordings. Although reliability of automated analysis has been investigated, suitability of one single analysis software for use with different devices is unclear. Here, validity of automatic analysis of recordings with two ambulatory devices and reliability of automatic analysis in detection of mixed and central apnoeas are investigated through 100 and 167 recordings with Venla and Embletta devices, respectively. Recordings were analysed automatically with Somnologica 3.2 and compared to manual analysis. Significant differences were seen between devices in classification of the severity of OSA when automatic analysis was applied. 65.4% and 11.4% of patients with mild obstructive sleep apnoea received false negative diagnosis with Venla and Embletta, respectively. Further, as automatic analysis was seen to have major difficulty in detection and classification of central and mixed apnoeas, manual analysis is suggested when these forms of disease are suspected.

Sleep-disordered breathing is related to an increased risk for type 2 diabetes in middle-aged men, but not in women--the FIN-D2D survey

AIM

To determine the association between sleep-disordered breathing (SDB) and obesity, diabetes and glucose intolerance among middle-aged men and women in Finland.

METHODS

A multicentre, population-based, cross-sectional survey in Finland. A total of 1396 men and 1500 women aged 45-74 years participated in the survey between 2004 and 2005. The study subjects underwent a health examination including an oral glucose tolerance test and filled a questionnaire describing their sleep habits.

RESULTS

Middle-aged men with SDB had an increased prevalence of diabetes and abnormal glucose tolerance. These associations were not found among middle-aged women. After adjustments for age, body mass index, smoking and central nervous system-affecting medication, SDB was independently associated with diabetes and glucose intolerance in men, but not in women.

CONCLUSION

Middle-aged men with SDB have an independent risk of type 2 diabetes. However, both diabetes and SDB exhibit a strong association with obesity and especially with central obesity, reflecting increased visceral fat. In clinical practice especially male patients with diabetes should always be asked about habitual snoring and about possible sleep apnoea.

Parenteral ketoprofen for pain management after adenoidectomy: comparison of intravenous and intramuscular routes of administration

BACKGROUND

Different parenteral routes of administration of NSAIDs such as ketoprofen have not been properly compared in children. This study was designed to compare the analgesic efficacy of intravenous and intramuscular ketoprofen for pain management in children after day-case adenoidectomy.

METHODS

A total of 120 children, aged 1-9 years, who were scheduled to undergo adenoidectomy, were randomized to receive ketoprofen 2 mg/kg either intravenously with intramuscular placebo (n = 40) or ketoprofen 2 mg/kg intramuscularly with intravenous placebo (n = 40), or both intravenous and intramuscular placebo (n = 40) at induction of anesthesia. The study design was prospective and double-blind with parallel groups. Pain was assessed at rest and during swallowing using the Maunuksela pain scale during 3 h after surgery, and fentanyl i.v. was given for rescue analgesia.

RESULTS

Children in the Placebo group needed significantly more doses of fentanyl (72 doses) than either children in the intravenous group (47 doses) or children in the intramuscular group (51 doses) (P = 0.021). In addition, a higher proportion of children in the Placebo group than in the two ketoprofen groups (P = 0.03) demanded rescue analgesic. No difference in the need for rescue analgesia or in pain scores was found between the two ketoprofen groups. Children in the intravenous group had less pain than children in the Placebo group. The difference was significant during swallowing at 1 h after surgery (P = 0.046) and for the worst pain observed during swallowing for 3 h after surgery (P = 0.022). There were no differences between the three groups with respect to operation times, amount of perioperative bleeding, or rate or extent of adverse events.

CONCLUSION

The efficacy of intravenous and intramuscular ketoprofen was similar, and they both differed from placebo.

Pharmacokinetics of ketoprofen following oral and intramuscular administration in young children

OBJECTIVE

The pharmacokinetics of ketoprofen following intramuscular injection or oral tablet was determined in children aged 10-69 months.

METHODS

Ten children received a single intramuscular injection of 1 mg kg(-1) ketoprofen. Six children, weight 12-17 kg, received a 12.5-mg ketoprofen tablet and four children, weight 18-23 kg, received a 25-mg tablet. Venous blood samples were collected at 15 min and 30 min and 1, 2, 4, 6 and 8 h following drug dosing. Plasma ketoprofen levels were measured using a validated high-performance liquid chromatography method.

RESULTS

The maximal plasma concentration of ketoprofen ranged between 3.6 microg ml(-1) and 7.4 microg ml(-1) in the intramuscular group and, following a dose normalisation, between 2.8 microg ml(-1) and 8.2 microg ml(-1) in the tablet group (dose normalised for 1 mg kg(-1)). The rate and extent of absorption of ketoprofen were comparable after intramuscular and oral administration. The relative bioavailability of oral ketoprofen was about 100% of the intramuscular administration. The extrapolated area under the plasma concentration-time curve (AUC0-infinity) ranged between 8.8 microg ml(-1) h and 14.6 microg ml(-1) h in the intramuscular group and between 8.7 microg ml(-1) h and 14.1 microg ml(-1) h in the tablet group (dose-normalised AUC0-infinity). The terminal half-life was comparable in both study groups, ranging between 0.8 h and 2.2 h in the intramuscular group and between 0.9 h and 2.1 h in the tablet group.

CONCLUSION

According to the pharmacokinetic properties determined in this study, there is no justification for using intramuscular administration in awake children.

Pain management after adenoidectomy with ketoprofen: comparison of rectal and intravenous routes

We compared the efficacy of rectally and intravenously administered ketoprofen for pain management after day-case adenoidectomy. Patients (123 children aged 1-9 yr) were allocated randomly to receive on induction of anaesthesia ketoprofen 25 mg rectally with an i.v. placebo, ketoprofen 25 mg i.v. with a rectal placebo, or placebo both i.v. and rectally. The method of anaesthesia and the operative technique were standardized. Postoperative pain was assessed at rest and during swallowing using the Maunuksela pain scale (0=no pain, 10=worst possible pain). Fentanyl 0.5 microg kg(-1) was given as rescue analgesia. There was no significant difference between the two ketoprofen groups in their requirement for rescue analgesics. However, both the proportion of children needing rescue analgesics [55 of 84 children (65%) vs. 33 of 39 children (84%); difference 19%, 95% confidence interval 4-34%, P=0.029] and the number of rescue analgesic doses [mean 1.2 (SD 1.2) vs. 2.2 (1.4); mean difference 0.9, 95% confidence interval 0.4-1.4, P=0.001] were significantly lower among children receiving ketoprofen than in children receiving placebo. Adverse events, duration of operation, perioperative bleeding, pain scores and time of discharge were similar in the three groups.

Comparison of intravenous and oral ketoprofen for postoperative pain after adenoidectomy in children

One hundred children, aged 1-9 yr, undergoing adenoidectomy were randomized to receive ketoprofen 1 mg kg-1 either i.v. with an oral placebo (n = 40) or ketoprofen 1 mg kg-1 orally with an i.v. placebo (n = 40), or both oral and i.v. placebo (n = 20). The study design was prospective and double blind with parallel groups. The pain was assessed at rest and during swallowing using the Maunuksela pain scale (0 = no pain, 10 = worst possible pain) after surgery for 3 h. Fentanyl 0.5 microgram kg-1 i.v. was given for rescue analgesia. Children in the i.v. group needed significantly less doses (1, 1-3; median and 10th/90th percentiles) of rescue analgesic compared with the oral group (2, 1-3; P = 0.024). Of those who needed rescue analgesic, three out of 30 children in the i.v. group required three or more doses of fentanyl compared with 10 out of 28 children in the oral group. There were no differences between the groups with respect to pain scores, operation times, perioperative bleeding or frequency of adverse events.