Oxidative and carbonyl stress in pregnant women with obstructive sleep apnea.

PURPOSE: Pregnant women are particularly susceptible to sleep-disordered breathing. Obstructive sleep apnea (OSA) in pregnancy is associated with poor pregnancy and fetal outcomes. Oxidative stress caused by intermittent hypoxemia and reoxygenation may impact pregnancy health. We hypothesize that pregnant women with OSA have a pronounced oxidative stress profile. METHODS: A case-control study was performed to study oxidative stress markers in the serum of pregnant women with or without OSA. Patients with OSA were identified between 2003 and 2009. Contemporaneous controls were pregnant subjects without apnea, gasping, or snoring around the time of delivery. Serum markers of oxidative and carbonyl stress were measured by spectrophotometric/fluorometric methods. Multiple linear regression analysis was used with a model including age, body mass index at delivery, history of diabetes, and gestational age. RESULTS: Serum samples from 23 OSA cases and 41 controls were identified. Advanced oxidation protein products, a marker for oxidative stress, and advanced glycation end products (AGEs), a marker for carbonyl stress, were significantly lower in women with OSA than in controls (p value <0.0001). Total antioxidant capacity was higher in women with OSA in comparison to controls (p value <0.0001). The difference in AGEs remained significant even after adjusting for confounders. CONCLUSION: Contrary to our hypothesis, the results of this study suggest that pregnant women with OSA have higher antioxidant capacity and lower oxidative and carbonyl stress markers compared to controls, suggesting a possible protective effect of intermittent hypoxia. Whether OSA in pregnancy impacts oxidative stress differently than OSA in the general population remains to be confirmed.

Effect of Fecal Microbiota Transplantation on Recurrence in Multiply Recurrent Clostridium difficile Infection: A Randomized Trial.

BACKGROUND: To date, evidence for the efficacy of fecal microbiota transplantation (FMT) in recurrent Clostridium difficile infection (CDI) has been limited to case series and open-label clinical trials. OBJECTIVE: To determine the efficacy and safety of FMT for treatment of recurrent CDI. DESIGN: Randomized, controlled, double-blind clinical trial. (ClinicalTrials.gov: NCT01703494). SETTING: Two academic medical centers. PATIENTS: 46 patients who had 3 or more recurrences of CDI and received a full course of vancomycin for their most recent acute episode. INTERVENTION: Fecal microbiota transplantation with donor stool (heterologous) or patient's own stool (autologous) administered by colonoscopy. MEASUREMENTS: The primary end point was resolution of diarrhea without the need for further anti-CDI therapy during the 8-week follow-up. Safety data were compared between treatment groups via review of adverse events (AEs), serious AEs (SAEs), and new medical conditions for 6 months after FMT. Fecal microbiota analyses were performed on patients' stool before and after FMT and also on donors' stool. RESULTS: In the intention-to-treat analysis, 20 of 22 patients (90.9%) in the donor FMT group achieved clinical cure compared with 15 of 24 (62.5%) in the autologous FMT group (P = 0.042). Resolution after autologous FMT differed by site (9 of 10 vs. 6 of 14 [P = 0.033]). All 9 patients who developed recurrent CDI after autologous FMT were free of further CDI after subsequent donor FMT. There were no SAEs related to FMT. Donor FMT restored gut bacterial community diversity and composition to resemble that of healthy donors. LIMITATION: The study included only patients who had 3 or more recurrences and excluded those who were immunocompromised and aged 75 years or older. CONCLUSION: Donor stool administered via colonoscopy seemed safe and was more efficacious than autologous FMT in preventing further CDI episodes. PRIMARY FUNDING SOURCE: National Institute of Diabetes and Digestive and Kidney Diseases.

Placenta-secreted circulating markers in pregnant women with obstructive sleep apnea.

AIMS: Obstructive sleep apnea (OSA) is associated with placenta-mediated adverse clinical outcomes. We aimed at comparing placenta-secreted proteins, such as first and second trimester Down syndrome screening markers which have been linked to preeclampsia, and markers of angiogenesis in pregnant women with OSA, and pregnant controls at low risk for OSA. METHODS: A case-control study of pregnant women with OSA and controls at low risk for OSA was performed. Levels of first and second trimester markers were reported as multiple of median (MoM), and adjusted for body mass index (BMI). Stored samples were tested for markers of angiogenesis and adjusted for gestational age, BMI, and chronic hypertension. RESULTS: A total of 24 women with OSA and 166 controls had screening markers. BMI was higher in cases compared to controls, P=0.01. MoM levels of placenta associated plasma protein-A (PAPP-A) were significantly lower in cases versus controls, even after adjusting for BMI (0.52 IQR 0.48 vs. 1.01 IQR 0.63, P=0.009). The ratio of soluble vascular endothelial growth factor receptor 1 to placental growth factor was significantly higher in cases than controls, even after adjusting for confounders (4.42 IQR 2.52 vs. 2.93 IQR 2.01, P=0.009). CONCLUSION: Circulating placenta-secreted glycoproteins and markers of angiogenesis are altered in pregnant women with OSA.

Snoring and markers of fetal and placental wellbeing.

INTRODUCTION: Snoring, the symptom of partial airway obstruction during sleep, is a common complaint during pregnancy and is associated with adverse perinatal outcomes. Mechanisms underlying this association have not been studied. We investigated the relationship between snoring in pregnancy and maternal serum markers of feto-placental wellbeing. METHODS: We conducted a secondary analysis of a cross sectional study designed to investigate perinatal outcomes of sleep-disordered breathing. Women admitted for delivery were systematically selected and answered a questionnaire about snoring using the Multivariable Apnea Prediction Index. Participants who had screening markers measured were included and divided into snorers and non -snorers. Markers measured included first and second trimester Down syndrome screening markers, reported as multiples of the median (MoM). An additional analysis was performed with snorers categorized as acute or chronic snorers based on duration of snoring in relation to pregnancy. RESULTS: While significant differences were noted in co-morbid maternal medical conditions between snorers and non-snorers, there were no significant differences in the neonatal outcomes assessed between the two groups. No significant differences were noted in any of the first trimester (PAPP-A) or second trimester (AFP, uE3, hCG, inhibin-A) markers between snorers and non-snorers, p > 0.25. In addition, no significant differences in marker levels were noted between acute and chronic snorers. CONCLUSION: Snoring is not associated with alterations in the markers of fetal or placental wellbeing tested here and suggests that there are alternative mechanisms underlying the association between snoring and adverse perinatal outcomes.

Serum Progesterone Levels in Pregnant Women with Obstructive Sleep Apnea: A Case Control Study.

BACKGROUND: Pregnancy is a risk factor for sleep disordered breathing, including obstructive sleep apnea (OSA). Progesterone, one of the key hormones in pregnancy, a known respiratory drive stimulant, increases ventilation and may protect against OSA. We aimed to examine the relationship between circulating progesterone and OSA, after accounting for body weight and gestational age. METHODS: A case control study was conducted of pregnant women with OSA and those at low risk for the disorder. Cases were identified by ICD-9 code and review of medical record. Controls were identified if they scored zero (never) for snoring, apnea, and gasping on the multivariable apnea prediction index questionnaire immediately following delivery. Subjects with available stored first and/or second trimester residual serum samples were then included in this study and serum analyzed for progesterone. Raw progesterone levels were adjusted for the effects of gestational age and maternal weight. RESULTS: Twenty-seven cases and 64 controls with available serum were identified. Women with OSA had greater maternal weight and higher rates of related comorbidities, compared to controls. Progesterone levels correlated positively with gestational age and negatively with greater weight. Progesterone levels, adjusted for gestational age and maternal weight and expressed as multiples of median (MoM), were significantly lower in OSA cases compared to controls in both the first trimester (MoM = 0.71, confidence interval [95% CI] 0.60-0.83) relative to the MoM in controls of 1.00. In the second trimester levels were also lower in OSA cases (MoM = 0.84, 95% CI 0.73-0.96) compared to the MoM of 1.00 in controls. CONCLUSIONS: Progesterone levels, after accounting for weight and gestational age, were lower in women with OSA than controls. Progesterone may play a protective role against OSA.

Obstructive sleep apnea is associated with alterations in markers of fetoplacental wellbeing.

BACKGROUND: Obstructive sleep apnea (OSA) has been associated with adverse fetal outcomes in some studies. Second trimester Down syndrome screening markers reflect fetal and fetoplacental wellbeing. We aimed to compare markers of fetal and feto-placental wellbeing in women with OSA and low risk controls. METHODS: A retrospective case-control study of pregnant women with OSA and available second trimester markers was performed. Controls were screened for sleep disordered breathing (SDB) at the time of delivery using a questionnaire. Women at low risk for OSA were selected. Marker levels were adjusted for gestational age and race and reported as multiples of median and later adjusted for body mass index (BMI). RESULTS: Twenty-four OSA cases and 166 controls were identified. Women with OSA had a higher mean BMI when compared to controls (37.1 ± 12.7 versus 24.1 ± 5.1, p = 0.03). Estriol (uE3) multiples of the median (MoM) levels were lower in women with OSA compared to controls, even after adjusting for BMI, 0.74 (interquartile range (IQR) 0.45) versus 1.06 (IQR 0.38), respectively, p = 0.026. Once adjusted for BMI, alpha feto-protein (AFP) MoM levels were no longer significantly different in women with OSA compared to controls. CONCLUSION: OSA is associated with reduced serum uE3 levels, independently of BMI, possibly indicating fetal distress.