Mannitol challenge testing for asthma in a community cohort of young adults.

BACKGROUND AND OBJECTIVE: Mannitol challenge testing is an established tool for clinical asthma diagnosis, and can be performed outside of specialized respiratory laboratories. Despite applicability in both clinical and non-clinical populations, with different pre-test asthma probabilities, differences in diagnostic properties have not been well explored. This study aimed to quantify the diagnostic utility of mannitol challenge testing for asthma in a community cohort and a symptomatic wheezing subset of this cohort. METHODS: During the 22-year follow-up of the Western Australian Pregnancy (Raine) Cohort, 772 participants (384 males) completed mannitol challenge and skin prick testing and respiratory health questionnaires, of whom 148 reporting wheeze in the past 12 months were included in a wheezing subset. RESULTS: Responsiveness to mannitol had low sensitivity (19%) and high specificity (97%) to identify current asthma in the complete cohort, with positive and negative predictive values (PPV and NPV) of 45% and 92%, respectively. Within the wheezing subset, sensitivity (19%) and specificity (94%) remained similar, but PPV increased to 79%, and NPV decreased to 52%. CONCLUSION: Our findings support previously reported high specificity and good PPV for mannitol challenge testing in symptomatic wheezing populations, and highlight the need for caution when interpreting mannitol test results in non-clinical populations.

The prevalence of symptoms of depression and anxiety, and the level of life stress and worry in New Zealand Maori and non-Maori women in late pregnancy.

OBJECTIVE: To describe the prevalence of symptoms of depression and anxiety, and the level of life stress and worry in late pregnancy for Maori and non-Maori women. METHODS: In late pregnancy, women completed a questionnaire recording their prior history of mood disorders; self-reported current depressive symptoms (⩾13 on the Edinburgh Postnatal Depression Scale), current anxiety symptoms (⩾6 on the anxiety items from the Edinburgh Postnatal Depression Scale), significant life stress (⩾2 items on life stress scale) and dysfunctional worry (>12 on the Brief Measure of Worry Scale). RESULTS: Data were obtained from 406 Maori women (mean age = 27.6 years, standard deviation=6.3 years) and 738 non-Maori women (mean age = 31.6 years, standard deviation=5.3 years). Depressive symptoms (22% vs 15%), anxiety symptoms (25% vs 20%), significant life stress (55% vs 30%) and a period of poor mood during the current pregnancy (18% vs 14%) were more prevalent for Maori than non-Maori women. Less than 50% of women who had experienced ⩾2 weeks of poor mood during the current pregnancy had sought help. Being young was an independent risk factor for depressive symptoms, significant life stress and dysfunctional worry. A prior history of depression was also consistently associated with a greater risk of negative affect in pregnancy. CONCLUSION: Antenatal mental health requires at least as much attention and resourcing as mental health in the postpartum period. Services need to specifically target Maori women, young women and women with a prior history of depression.

Maternal sleep disturbances in late pregnancy and the association with emergency caesarean section: A prospective cohort study.

OBJECTIVES: To investigate the association between measures of sleep quality, sleep duration and sleep disorder symptoms in late pregnancy and likelihood of emergency caesarean section. DESIGN: Population-based prospective cohort study SETTING: New Zealand PARTICIPANTS: 310 Maori (Indigenous New Zealanders) and 629 non-Maori women MEASUREMENTS: Multivariable logistic regression models were used to investigate the association between type of delivery (emergency caesarean section vs. spontaneous vaginal delivery) and self-reported sleep duration, sleep quality and sleep-related symptoms, (e.g. snoring, breathing pauses during sleep, legs twitching/jerking) in the third trimester of pregnancy. Models were adjusted by ethnicity (ref=non-Maori), age (ref=16-19 y), parity (ref=nulliparous), clinical indicators (any vs. none), area deprivation (ref=least deprived quintile), BMI and for some models smoking. RESULTS: Women who reported poor quality sleep as measured by the General Sleep Disturbance Scale in later pregnancy had almost twice the odds of delivering via emergency caesarean than women with good sleep quality (OR=1.98, 95% CI 1.18-3.31). Reporting current breathing pauses during sleep (OR=3.27, 95% CI 1.38-7.74) or current snoring (OR=1.65, 95% CI 1.00-2.72) were also independently associated with a higher likelihood of an emergency caesarean. Short sleep duration and leg twitching/jerking were not independently associated with emergency caesarean section in this study. CONCLUSIONS: Supporting healthy sleep during pregnancy could be a novel intervention to reduce the risks associated with emergency caesarean section. Research on the effectiveness of sleep interventions for reducing caesarean section risk is required.

Self-reported sleep in late pregnancy in relation to birth size and fetal distress: the E Moe, Mama prospective cohort study.

OBJECTIVES: To explore associations between features of sleep during pregnancy and adverse outcomes for the infant. SETTING: E Moe, Mama is a cohort study in Aotearoa/New Zealand that investigates self-reported sleep and maternal health in late pregnancy and the postpartum period. PARTICIPANTS: Women (N=633; 194 Maori) reported detailed information on their sleep duration, quality, disturbances, disorders (snoring, breathing pauses, twitching legs, restless legs) and daytime sleepiness between 35 and 37 weeks gestation. OUTCOME MEASURES: Birthweight and fetal distress during labour were extracted from medical records. Associations between each sleep variable and small or large for gestational age (SGA/LGA) using customised birthweight centile or fetal distress were estimated using multinomial/logistic regression, controlling for potential confounders. Secondary analyses considered differences in associations between Maori and non-Maori women. RESULTS: There was some indication that breathing pauses (a measure of sleep apnoea) were associated with both SGA (OR 2.8, 95% CI 0.9 to 9.0, p=0.08) and LGA (OR 2.0, 95% CI 0.7 to 5.7, p=0.20), with the association for LGA being stronger when only pregnancy-onset breathing pauses were considered (OR 3.5, 95% CI 1.3 to 9.6, p=0.01). There was also some evidence that pregnancy-onset leg twitching (OR 3.3, 95% CI 1.1 to 10.0, p=0.03) and frequent sleep disturbance due to feeling too hot or too cold (OR 1.7, 95% CI 0.9 to 3.6, p=0.13) were associated with higher risk of fetal distress. Other sleep measures, including snoring, were not associated with SGA, LGA or fetal distress. Many of the associations we observed were considerably stronger in Maori compared with non-Maori women. CONCLUSIONS: We did not find evidence of previously reported associations between snoring and SGA. Our findings tentatively suggest that self-reported breathing pauses and leg twitching in late pregnancy are associated with infant outcomes, and highlight ethnic inequalities.

Prevalence of abnormal sleep duration and excessive daytime sleepiness in pregnancy and the role of socio-demographic factors: comparing pregnant women with women in the general population.

OBJECTIVES: To compare the prevalence of self-reported abnormal sleep duration and excessive daytime sleepiness in pregnancy among Maori (indigenous New Zealanders) and non-Maori women versus the general population, and to examine the influence of socio-demographic factors. METHODS: Self-reported total sleep time (TST) in 24-hrs, Epworth Sleepiness Scale scores and socio-demographic information were obtained from nullipara and multipara women aged 20-46 yrs at 35-37 weeks pregnant (358 Maori and 717 non-Maori), and women in the general population (381 Maori and 577 non-Maori). RESULTS: After controlling for ethnicity, age, socio-economic status, and employment status, pregnant women average 30 min less TST than women in the general population. The distribution of TST was also greater in pregnant women, who were 3 times more likely to be short sleepers (≤6 h) and 1.9 times more likely to be long sleepers (>9 h). In addition, pregnant women were 1.8 times more likely to report excessive daytime sleepiness (EDS). Pregnant women >30 years of age experienced greater age-related declines in TST. Identifying as Maori, being unemployed, and working at night increased the likelihood of reporting abnormal sleep duration across all women population in this study. EDS also more likely occurred among Maori women and women who worked at night. CONCLUSIONS: Pregnancy increases the prevalence of abnormal sleep duration and EDS, which are also higher among Maori than non-Maori women and those who do night work. Health professionals responsible for the care of pregnant women need to be well-educated about the importance of sleep and discuss sleep issues with the women they care for.