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• Helminthiasis in children is positively associated with asthma. • The extent of helminth infestation is not associated with asthma. • Trichiuris trichura but no other helminths are associated with asthma. The association between helminthiasis and asthma remains inconclusive but can only be investigated in counties where helminthiasis is transitioning from a high to low burden. We investigated this association using data from a childhood respiratory cohort in Sri Lanka. A case-control study was nested within a population-based cohort of children aged 6-14 years in Sri Lanka. The stool samples of 190 children with asthma and 190 children without asthma were analyzed to assess the burden of helminth infestation. Logistic regression models were fitted to investigate the association of gastrointestinal helminth species with asthma. Helminthiasis in children with and without asthma was 23.3% (n = 44) and 15.3% (n = 23), respectively. Those with asthma were more likely to have helminthiasis (odds ratio 3.7; 95% confidence interval 1.7, 7.7; P = 0.001), particularly with Trichiuris trichura (odds ratio 4.5; 95% confidence interval 1.6, 12.3; P = 0.004). Helminth eggs per gram of feces were not associated with asthma (P >0.05). Our findings demonstrate a positive association between T. trichura infestation and asthma and point to the need to fully characterize this association to understand the likely immunological mechanism that drives it. This association highlights an important public health intervention in countries where these infestations are still prevalent, affecting 24% of the population worldwide. [ABSTRACT FROM AUTHOR]

Despite substantial disease burden, existing evidence on the risk factors for obstructive sleep apnea (OSA) have been derived primarily from cross-sectional studies without determining temporality. Therefore, we aimed to systematically synthesize the literature on longitudinal risk factors for sleep study-assessed OSA and questionnaire-assessed probable OSA from cohort studies in the general adult population settings. We systematically searched Embase and Medline (on OVID) databases. Eleven studies met the inclusion criteria. Meta-analyses were not conducted due to methodological heterogeneity of exposure and outcome measurements. There was consistent evidence that weight gain was associated with incident (n = 2) and greater severity (n = 2) of OSA. One study each observed an association of higher baseline body-mass index, male sex, asthma, a specific genetic polymorphism in rs12415421 , and insulin resistance/hyperglycemia, with incident OSA. Long-term exposure to ambient air pollution (NO 2 , n = 1) was associated with OSA, and menopausal transitions (n = 1) with higher apnea-hypopnea index. There were no eligible studies on long-term smoking or alcohol use. In conclusion, approximately 10% increase in weight, especially in males, might alert clinicians to consider potential or worsening OSA. Large, well-designed longitudinal studies are needed to consolidate knowledge on other associations with OSA development, especially on potentially modifiable risk factors. [ABSTRACT FROM AUTHOR]

This review aimed to examine the relationship between surgical weight loss and obstructive sleep apnoea (OSA) severity (i.e., apnoea-hypopnoea index [AHI]), and how this relationship is altered by the various respiratory events scoring (RES) criteria used to derive the AHI. A systematic search of the literature was performed up to December 2017. Before-and-after studies were considered due to a paucity of randomised controlled trials (RCTs) available to be reviewed in isolation. Primary outcomes included pre- and post-surgery AHI and body mass index (BMI). Secondary outcomes included sleep study type and RES criteria. Meta-analysis was undertaken where possible. Overall, surgical weight loss resulted in reduction of BMI and AHI, however, OSA persisted at follow-up in the majority of subjects. There was high between-study heterogeneity which was largely attributable to baseline AHI and duration of follow-up when analysed using meta-regression. There was insufficient data to evaluate the impact of different RES criteria on OSA severity. Therefore, more RCTs are needed to verify these findings given the high degree of heterogeneity and future studies are strongly encouraged to report the RES criteria used to enable fair and uniform comparisons of the impact of any intervention on OSA severity. [ABSTRACT FROM AUTHOR]

We aimed to systematically review the Berlin questionnaire as a screening tool for obstructive sleep apnea. We systematically searched PubMed, Embase, and Scopus databases, reviewed articles reporting the Berlin questionnaire's diagnostic utility as measured against type-1 polysomnography, and performed meta-analyses where possible. Thirty five eligible articles showed that the Berlin questionnaire's diagnostic utility varied by study population, definition of hypopnea used, and apnea-hypopnea index threshold used. It had good sensitivity and specificity for detecting clinically relevant obstructive sleep apnea as well as any obstructive sleep apnea in the sleep clinic population. Despite limited evidence, it showed modest to high sensitivity for detecting clinically relevant obstructive sleep apnea or any obstructive sleep apnea in other clinical and general population subgroups. Its specificity was relatively low. Possible reasons for variability in reported diagnostic utility of the Berlin questionnaire are multifaceted. We conclude that the Berlin questionnaire is useful as a clinical screening test and epidemiological tool in the sleep clinic population. Despite limited evidence, it likely has potential clinical and research utility in other populations. Adopting more consistent methodological definitions and focussing more on the general population and specific clinical populations to determine its usefulness as a clinical or epidemiological screening tool are recommended. [ABSTRACT FROM AUTHOR]

With this systematic review we aimed to determine the prevalence of obstructive sleep apnea (OSA) in adults in the general population and how it varied between population sub-groups. Twenty-four studies out of 3807 found by systematically searching PubMed and Embase databases were included in this review. Substantial methodological heterogeneity in population prevalence studies has caused a wide variation in the reported prevalence, which, in general, is high. At ≥5 events/h apnea-hypopnea index (AHI), the overall population prevalence ranged from 9% to 38% and was higher in men. It increased with increasing age and, in some elderly groups, was as high as 90% in men and 78% in women. At ≥15 events/h AHI, the prevalence in the general adult population ranged from 6% to 17%, being as high as 49% in the advanced ages. OSA prevalence was also greater in obese men and women. This systematic review of the overall body of evidence confirms that advancing age, male sex, and higher body-mass index increase OSA prevalence. The need to a) consider OSA as having a continuum in the general population and b) generate consensus on methodology and diagnostic threshold to define OSA so that the prevalence of OSA can be validly compared across regions and countries, and within age-/sex-specific subgroups, is highlighted. [ABSTRACT FROM AUTHOR]

The objective of this systematic review is to synthesize the evidence on prevalence, polysomnographic findings and clinical outcomes of co-morbid obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) - known as the "overlap syndrome". We systematically searched PubMed on 1 December 2015 using appropriate medical subject headings (MeSH) and text words to capture prevalence studies and comparative studies of any observational design examining the clinical outcomes in patients with co-existent COPD and OSA. We reviewed 591 articles and included 27 in the final review. In total, 21 observational studies (n = 29,341 participants) provided prevalence estimates. Overlap syndrome is not common in the general and hospital population (range: 1.0-3.6%), but is highly prevalent in patients diagnosed with either obstructive sleep apnea (range: 7.6-55.7%) or COPD (range: 2.9-65.9%). Overlap syndrome patients have been shown to have greater nocturnal oxygen desaturation (NOD) (i.e., reduced mean peripheral capillary oxygen saturation (SpO2) and increased sleep time spent with SpO2 < 90% (T90)) and worse sleep quality than patients with only OSA. It is associated with more frequent cardiovascular morbidity, poorer quality of life (QoL), more frequent COPD exacerbation and increased medical costs. This systematic review on overlap syndrome highlights the limitations and knowledge gaps of its prevalence, etiology and underlying pathophysiologic mechanisms related to increased morbidity and mortality. [ABSTRACT FROM AUTHOR]

Recent evidence suggests that air pollution exposure may be a contributing risk factor for obstructive sleep apnea (OSA), however, current evidence is conflicting. This systematic review aims to determine the association between air pollution and OSA in the general population, and examine for potential effect modification by seasonality, temperature and humidity. Five full-text articles were included in the review out of 905 articles found by systematically searching PubMed, Embase and Scopus databases. The included studies were limited to OSA in adults that were conducted in middle to high-income countries. The results highlight heterogeneity in the diagnostic criteria for OSA and method used to assess air pollution exposure. There is some evidence to support a relationship between air pollution exposure and OSA. However, the duration of exposure to different air pollutants including particulate matter (PM2.5 and PM10) and nitric oxides (NO2) in relation to OSA varied across different seasons, temperatures, and countries. This variability of the pollutants across studies warrants a more robust study design using time-series analysis with multiple follow-ups to strengthen the evidence for this relationship before considering its implications. [ABSTRACT FROM AUTHOR]