Edwin Trevathan

Association between long-term air pollution and increased blood pressure and hypertension in China.

Several studies have investigated the short-term effects of ambient air pollutants in the development of high blood pressure and hypertension. However, little information exists regarding the health effects of long-term exposure. To investigate the association between residential long-term exposure to air pollution and blood pressure and hypertension, we studied 24 845 Chinese adults in 11 districts of 3 northeastern cities from 2009 to 2010. Three-year average concentration of particles with an aerodynamic diameter ⩽10 µm (PM10), sulfur dioxide (SO2), nitrogen dioxides (NO2), and ozone (O3) were calculated from monitoring stations in the 11 districts. We used generalized additive models and 2-level logistic regressions models to examine the health effects. The results showed that the odds ratio for hypertension increased by 1.12 (95% confidence interval [CI], 1.08–1.16) per 19 &mgr;g/m3 increase in PM10, 1.11 (95% CI, 1.04–1.18) per 20 &mgr;g/m3 increase in SO2, and 1.13 (95% CI, 1.06–1.20) per 22 &mgr;g/m3 increase in O3. The estimated increases in mean systolic and diastolic blood pressure were 0.87 mm Hg (95% CI, 0.48–1.27) and 0.32 mm Hg (95% CI, 0.08–0.56) per 19 &mgr;g/m3 interquartile increase in PM10, 0.80 mm Hg (95% CI, 0.46–1.14) and 0.31 mm Hg (95% CI, 0.10–0.51) per 20 &mgr;g/m3 interquartile increase in SO2, and 0.73 mm Hg (95% CI, 0.35–1.11) and 0.37 mm Hg (95% CI, 0.14–0.61) per 22 &mgr;g/m3 interquartile increase in O3. These associations were only statistically significant in men. In conclusion, long-term exposure to PM10, SO2, and O3 was associated with increased arterial blood pressure and hypertension in the study population.

Clinical, neurological, and electrophysiological features of nodding syndrome in Kitgum, Uganda: an observational case series

BACKGROUND Nodding syndrome is an unexplained illness characterised by head-bobbing spells. The clinical and epidemiological features are incompletely described, and the explanation for the nodding and the underlying cause of nodding syndrome are unknown. We aimed to describe the clinical and neurological diagnostic features of this illness. METHODS In December, 2009, we did a multifaceted investigation to assess epidemiological and clinical illness features in 13 parishes in Kitgum District, Uganda. We defined a case as a previously healthy child aged 5-15 years with reported nodding and at least one other neurological deficit. Children from a systematic sample of a case-control investigation were enrolled in a clinical case series which included history, physical assessment, and neurological examinations; a subset had electroencephalography (EEG), electromyography, brain MRI, CSF analysis, or a combination of these analyses. We reassessed the available children 8 months later. FINDINGS We enrolled 23 children (median age 12 years, range 7-15 years) in the case-series investigation, all of whom reported at least daily head nodding. 14 children had reported seizures. Seven (30%) children had gross cognitive impairment, and children with nodding did worse on cognitive tasks than did age-matched controls, with significantly lower scores on tests of short-term recall and attention, semantic fluency and fund of knowledge, and motor praxis. We obtained CSF samples from 16 children, all of which had normal glucose and protein concentrations. EEG of 12 children with nodding syndrome showed disorganised, slow background (n=10), and interictal generalised 2·5-3·0 Hz spike and slow waves (n=10). Two children had nodding episodes during EEG, which showed generalised electrodecrement and paraspinal electromyography dropout consistent with atonic seizures. MRI in four of five children showed generalised cerebral and cerebellar atrophy. Reassessment of 12 children found that six worsened in their clinical condition between the first evaluation and the follow-up evaluation interval, as indicated by more frequent head nodding or seizure episodes, and none had cessation or decrease in frequency of these episodes. INTERPRETATION Nodding syndrome is an epidemic epilepsy associated with encephalopathy, with head nodding caused by atonic seizures. The natural history, cause, and management of the disorder remain to be determined. FUNDING Division of Global Disease Detection and Emergency Response, US Centers for Disease Control and Prevention.

Breastfeeding as a modifier of the respiratory effects of air pollution in children.

Background: Breastfeeding and air pollution are both important factors for respiratory symptoms and asthma in children. Few studies have examined possible interaction between them on respiratory outcomes. Methods: We studied 31,049 Chinese children, ages 2–14 years old, from 25 elementary schools and 50 kindergartens in the Seven Northeastern Cities during 2008–2009. Parents or guardians completed questionnaires about the children’s histories of respiratory conditions, risk factors, and feeding methods. Three-year average concentrations of particles with an aerodynamic diameter ⩽10 µm, sulfur dioxide, nitrogen dioxides, and ozone were calculated from monitoring stations in 25 study districts. We used two-level logistic regressions to examine the effects of exposure, controlling for covariates. Results: Association of air pollution with childhood respiratory conditions was modified by breastfeeding. Compared with children who had been breastfed, those who were not exhibited consistently stronger effects of air pollution. Among non-breastfed children, odds ratios (ORs) per 10 µg/m3 increase in nitrogen dioxide were 1.40 (95% confidence interval = 1.19–1.64) for cough, 1.41 (1.16–1.71) for phlegm, 1.17 (1.00–1.36) for current wheeze, and 1.25 (1.07–1.46) for doctor-diagnosed asthma. For breastfed children, the ORs were 1.25 (1.09–1.43) for cough, 1.15 (0.99–1.34) for phlegm, 0.97 (0.87–1.08) for current wheeze, and 1.17 (1.05–1.32) for doctor-diagnosed asthma. Breastfeeding was more protective among younger children. Breastfeeding was also associated with reduced effects of passive smoke exposure in children. Conclusion: Breastfeeding is associated with smaller associations between air pollution and respiratory conditions in children, suggesting that breastfeeding reduces susceptibility to the respiratory effects of pollutants.

Air pollution associated hypertension and increased blood pressure may be reduced by breastfeeding in Chinese children: The Seven Northeastern Cities Chinese Children's Study

BACKGROUND Little is known about the association between air pollution and hypertension among children, and no studies report whether breastfeeding modifies this association in children. METHODS Nine thousand three hundred fifty-four Chinese children, ages 5-17 years old, from 24 elementary schools and 24 middle schools in the Seven Northeastern Cities during 2012-2013 were evaluated. The weight, height, and BP were measured. Four-year average concentrations of particles with an aerodynamic diameter of ≤10 μm (PM10), sulfur dioxide (SO2), nitrogen dioxides (NO2), ozone (O3), and carbon monoxide (CO) were calculated from monitoring stations. Two-level regression analysis was used to examine the effects, controlling for covariates. RESULTS The results showed that associations existed between hypertension and pollutants. The odds ratios for hypertension ranged from 1.12 per 46.3 μg/m3 increase for O3 (95% confidence interval [CI], 1.10-1.13) to 1.68 per 30.6 μg/m3 increase for PM10 (95% CI, 1.53-1.86). The increases in mean diastolic BP ranged from 0.58 mm Hg per 46.3 μg/m3 increase for O3 (95% CI, 0.52-0.63 mm Hg) to 2.89 mm Hg per 563.4 μg/m3 increase for CO (95% CI: 2.53-3.24 mm Hg). The increase in systolic BP ranged from 0.50 mm Hg per 46.3 μg/m3 increase for O3 (95% CI: 0.43-0.57 mm Hg) to 2.10 mm Hg per 30.6 μg/m3 increase for PM10 (95% CI, 1.73-2.47 mm Hg). Compared with children who had been breastfed, non-breastfed children exhibited consistently stronger effects. CONCLUSION Study findings indicate that high levels of PM10, SO2, NO2, O3, and CO are associated with increased arterial BP and hypertension among the children. Breastfeeding may reduce the risk.

Poor sleep quality associated with high risk of hypertension and elevated blood pressure in China: results from a large population-based study.

Little information is available concerning the association between sleep quality and blood pressure (BP) in Chinese individuals. This study evaluated the association between sleep quality, as determined by the Pittsburgh sleep quality index (PSQI), and hypertension in a rural Chinese population. Using a multistage cluster and random sampling method, a representative sample of 9404 adults aged 20–93 years in northeastern China was selected from 2012 to 2013. Sleep quality was assessed by PSQI, and trained observers measured BP. A sleep disorder (SD) was diagnosed for any participant with a score of 6 or greater. Overall, 1218 male participants (25.53%) and 1261 female participants (27.22%) were defined as having SDs. Compared with the normal subjects, participants with hypertension had higher global PSQI scores and subscores in all elements. The odds ratios (ORs) of hypertension, systolic hypertension and diastolic hypertension among participants with SDs were 2.38 (95% confidence interval (CI): 2.13–2.65), 2.52 (95% CI: 2.26–2.80) and 1.93 (95% CI: 1.74–2.14) in contrast to the reference group, respectively. The risk for hypertension in poor sleepers with subscores over 0 in all of the elements was significantly increased, with ORs ranging from 1.16 (95% CI: 1.04–2.30) to 3.88 (95% CI: 1.24–12.16). The global PSQI score and its components were associated with hypertension and high BP.

Gender-specific differences of interaction between obesity and air pollution on stroke and cardiovascular diseases in Chinese adults from a high pollution range area: A large population based cross sectional study

BACKGROUND Little information exists regarding the interaction effects of obesity with long-term air pollution exposure on cardiovascular diseases (CVDs) and stroke in areas of high pollution. The aim of the present study is to examine whether obesity modifies CVD-related associations among people living in an industrial province of northeast China. METHODS We studied 24,845 Chinese adults, aged 18 to 74 years old, from three Northeastern Chinese cities in 2009 utilizing a cross-sectional study design. Body weight and height were measured by trained observers. Overweight and obesity were defined as a body mass index (BMI) between 25-29.9 and ≥30 kg/m(2), respectively. Prevalence rate and related risk factors of cardiovascular and cerebrovascular diseases were investigated by a questionnaire. Three-year (2006-2008) average concentrations of particulate matter (PM10), sulfur dioxide (SO2), nitrogen dioxides (NO2), and ozone (O3) were measured by fixed monitoring stations. All the participants lived within 1 km of air monitoring sites. Two-level logistic regression (personal level and district-specific pollutant level) was used to examine these effects, controlling for covariates. RESULTS We observed significant interactions between exposure and obesity on CVDs and stroke. The associations between annual pollutant concentrations and CVDs and stroke were strongest in obese subjects (OR 1.15-1.47 for stroke, 1.33-1.59 for CVDs), less strong in overweight subjects (OR 1.22-1.35 for stroke, 1.07-1.13 for CVDs), and weakest in normal weight subjects (OR ranged from 0.98-1.01 for stroke, 0.93-1.15 for CVDs). When stratified by gender, these interactions were significant only in women. CONCLUSIONS Study findings indicate that being overweight and obese may enhance the effects of air pollution on the prevalence of CVDs and stroke in Northeastern metropolitan China. Further studies will be needed to investigate the temporality of BMI relative to exposure and onset of disease.

Ambient air pollution and the prevalence of obesity in chinese children: The seven northeastern cities study

The association between air pollution and the prevalence of overweight and obesity is evaluated.

Home Renovation, Family History of Atopy, and Respiratory Symptoms and Asthma Among Children Living in China

OBJECTIVES To investigate the association of indoor air pollution with the respiratory health of children, we evaluated the associations of childrens respiratory symptoms with asthma and recent home renovation. METHODS We conducted a cross-sectional survey in a school recruitment sample of 31,049 children aged 2 to 14 years in 25 districts of 7 cities of northeast China in 2008-2009. The childrens parents completed standardized questionnaires characterizing the childrens histories of respiratory symptoms and illness, recent home renovation information, and other associated risk factors. RESULTS The effects of home renovation in the past 2 years were significantly associated with cough, phlegm, current wheeze, doctor-diagnosed asthma, and current asthma. The associations we computed when combining the status of home renovation and family history of atopy were higher than were those predicted from the combination of the separate effects. However, the interactions between home renovation and family history of atopy on a multiplicative scale were not statistically significant (P>.05). CONCLUSIONS Home renovation is associated with increases in the prevalence of respiratory symptoms and asthma in children. The effects of different renovation materials on child respiratory health should be studied further.

Parental Body Mass Index, Gestational Weight Gain, and Risk of Macrosomia: a Population-Based Case–Control Study in China

BACKGROUND The prevalence of macrosomia has risen markedly worldwide, including in China, during the past two decades. Few epidemiological studies, however, have investigated the risk factors for macrosomia in China. This study was designed to investigate the associations between parental anthropometric characteristics, gestational weight gain (GWG), and risk of macrosomia in China. METHODS This population-based, case-control study in Wuhan, China, included a total of 6341 subjects (870 cases and 5471 controls). Multivariable logistic regression was conducted to calculate odds ratios (OR) and 95% confidence intervals (CI). RESULTS Mothers or fathers who were overweight or obese before pregnancy had an elevated risk of giving birth to a macrosomic infant compared with their normal weight counterparts. Women with GWG above the Institute of Medicine (IOM) recommendation had an adjusted OR of 6.09 [95% CI 5.04, 7.35] for delivering a macrosomic infant compared with women who had GWG within the IOM recommendation. When stratified by maternal pre-pregnancy body mass index (BMI), women who were underweight or normal weight before pregnancy were observed to have a higher risk of macrosomia birth associated with greater GWG. CONCLUSIONS Parental pre-pregnancy overweight/obesity and excessive GWG during pregnancy were highly associated with macrosomia. The association with GWG was most pronounced in mothers who had a normal or underweight pre-pregnancy BMI. Weight control efforts before pregnancy for mothers and fathers as well as control of maternal gain during pregnancy may reduce the risk of macrosomia.

Residential characteristics and household risk factors and respiratory diseases in Chinese women: the Seven Northeast Cities (SNEC) study.

BACKGROUND Few studies have assessed the impact of residential home characteristics and home environmental risk factors on respiratory diseases in Chinese women. Therefore, this study sought to determine the association between residential home features, domestic pets, home renovation and other indoor environmental risk factors with respiratory health outcomes of Chinese women. METHODS This cross-sectional study included a study sample of 30,780 Chinese women aged 23 to 49 from 25 districts of seven cities in Liaoning Province, Northeast China. Information on respiratory health, residential characteristics, and indoor air pollution sources was obtained by a standard questionnaire from the American Thoracic Society. Multivariable logistic regression was used to estimate prevalence odds ratios (POR) and 95% confidence interval (95%CI). RESULTS The odds of respiratory diseases were higher for those who lived near the main road, or near ambient air pollution sources. Pet-keeping was associated with increased odds of chronic bronchitis (POR=1.40; 95%CI: 1.09-1.81) and doctor-diagnosed asthma (POR=2.07; 95%CI: 1.18-3.64). Additionally, humidifier use was associated with increased odds of chronic bronchitis (POR=1.44; 95%CI: 1.07-1.94). Home renovation in recent 2 years was associated with increased likelihood of allergic rhinitis (POR=1.39; 95%CI 1.17-1.64). CONCLUSION Home renovation and residential home environmental risk factors were associated with an increased likelihood of respiratory morbidity among Chinese women.