Search

Among infectious diseases, pneumonia is the greatest cause of mortality in children less than 5 years old. Approximately 27% of Beijing's 3-8 year-old children have had pneumonia at least once. The sole reservoir of pneumonia pathogens is the human nasopharynx. We investigated associations and interactions among two kinds of environmental risk factors: i) airborne pathogens, namely closed bedroom window and shared bedroom and ii) pollutants, namely traffic pollution and environmental tobacco smoke (ETS). We evaluated breastfeeding's (BF) protective value against childhood pneumonia. The database consists of responses to a questionnaire in a cross-sectional study. Crude and adjusted Odds Ratios were assessed independently for each risk factor. Combinations of the studied risk factors were analyzed using multivariate logistic regression. Risk factors were evaluated for interactions on the additive scale using the metrics Relative Excess Risk due to Interaction (RERI), Attributable Proportion (AP) and Synergy Index (S). All independent risk factors were significant for children's pneumonia. We also found evidence of possible synergistic interaction between pairs of risk factors that was stronger when one of the risk factors was a closed bedroom window. Remarkably, window opening was associated with reduced risk of pneumonia for children living near heavy traffic pollution. Longer duration BF was more protective than shorter, and exclusive BF was more protective than partial BF against childhood pneumonia. In conclusion, low ventilation (closed bedroom windows), shared bedroom, ETS, and traffic exposure were associated with increased risk of pneumonia. Exclusive BF for more than six months had the greatest protective value against pneumonia. • Closed bedroom window was associated with risk of childhood pneumonia in Beijing. • Shared bedroom, ETS and traffic pollution were also associated with pneumonia risk. • Closed bedroom window can interact synergistically with all other risk factors. • Exclusive Breastfeeding more than six months was most protective against pneumonia. [ABSTRACT FROM AUTHOR]

From October 2010 to April 2012, we conducted a cross‐sectional study of associations between household environments and childhood health among preschool children in eight Chinese cities. Here, we analyze associations of early household renovation with preterm birth (PTB), low birthweight (LBW), term low birthweight (Term‐LBW), and small for gestational age (SGA). Parents responded to questions about household renovation and their children's gestational age and birthweight. In the multivariate logistic regression analyses, household renovation in the year before pregnancy was significantly associated with LBW (sample size: N = 25 813; adjusted odds ratio (OR) with 95% confidence intervals (CIs): 1.23, 1.01‐1.50) and Term‐LBW (N = 24 823; 1.29, 1.01‐1.67). Household renovation during pregnancy was significantly associated with PTB (N = 25 202; 1.28, 1.01‐1.69). These significant associations were also found in the two‐level (city‐child) logistic regression analyses and in the sensitivity analyses among 21 009 children with complete data in all studied variates. Stronger associations were found in certain subgroups. Our findings indicate that household renovation within one year before pregnancy might be a risk factor for LBW and Term‐LBW, while household renovation during pregnancy could be a risk factor for PTB. [ABSTRACT FROM AUTHOR]

Objectives: To compare the proportion of Beijing children who have ever had pneumonia (%Pneumonia) to those in other locations, and to estimate by how much national vaccine coverage with Pneumococcal Conjugate Vaccine (PCV) and Haemophilus Influenzae Type b (Hib) could reduce Beijing %Pneumonia. Methods: %Pneumonia was obtained for each age group from 1 to 8 years inclusive from 5,876 responses to a cross-sectional questionnaire. Literature searches were conducted for world-wide reports of %Pneumonia. Previous vaccine trials conducted worldwide were used to estimate the pneumococcal (S. pneumoniae) and Hib (H. influenzae) burdens and %Pneumonia as well as the potential for PCV and Hib vaccines to reduce Beijing children’s %Pneumonia. Findings: The majority of pneumonia cases occurred by the age of three. The cumulative %Pneumonia for 3–8 year-old Beijing children, 26.9%, was only slightly higher than the 25.4% for the discrete 3 year-old age group, similar to trends for Tianjin (China) and Texas (USA). Beijing’s %Pneumonia is disproportionally high relative to its Gross National Income (GNI) per capita, and markedly higher than %Pneumonia in the US and other high GNI per capita countries. Chinese diagnostic guidelines recommend chest X-ray confirmation while most other countries discourage it in favor of clinical diagnosis. Literature review shows that chest X-ray confirmation returns far fewer pneumonia diagnoses than clinical diagnosis. Accordingly, Beijing’s %Pneumonia is likely higher than indicated by raw numbers. Vaccine trials suggest that national PCV and Hib vaccination could reduce Beijing’s %Pneumonia from 26.9% to 19.7% and 24.9% respectively. Conclusion: National PCV and Hib vaccination programs would substantially reduce Beijing children’s pneumonia incidence. [ABSTRACT FROM AUTHOR]

This study evaluated the prevalence and risk factors for asthma, allergy and related symptoms; and breastfeeding patterns and durations for 5479 Beijing children aged 3–6. Parents of children in randomly selected kindergartens wrote responses to a questionnaire used previously. The study aimed to evaluate trends in the prevalence of asthma and related illnesses, and to determine whether “more” breastfeeding, defined as exclusive, > 6 months, was associated with reduced prevalence. Asthma has increased in this age group between 1990 and 2011, with the steepest increase in the last 2–3 years. Of the total, 14.2% (779) children were breastfed exclusively for > 6 months. The efficacy of “more” breastfeeding was tested in a subset with two strong risk factors, positive family history (for asthma and/or allergy) and male gender. “More” breastfeeding was found to be significantly protective (aOR 0.42, P < 0.05) for this subset against Doctor-diagnosed asthma (D-asthma). Protection that did not reach statistical significance was also found for this subset against Wheeze ever, Cough at night, Rhinitis ever, Doctor-diagnosed rhinitis (D-rhinitis) and Eczema. The greatest protective effects were found for girls with no family history of asthma or allergy, reaching statistical significance for Wheeze ever (aOR 0.48, P < 0.01), Cough at night (aOR 0.47, P < 0.01), D-asthma (aOR 0.14, P < 0.01) and Rhinitis ever (aOR 0.67, P < 0.05). “More” breastfeeding was not consistently associated with either a protective or risk effect for Eczema. [ABSTRACT FROM AUTHOR]

In 1958, Edelman and colleagues empirically showed plasma sodium concentration ([Na+]p) to be primarily a function of the sum of exchangeable sodium and potassium (E) divided by total body water (TBW). Based on Edelman’s equation, Nguyen and Kurtz derived an equation to show how [Na+]p changes as a function of TBW, change in TBW (ΔTBW), and change in the sum of exchangeable sodium and potassium (ΔE). Using the Nguyen-Kurtz equation, the present study examines the sensitivity of [Na+]p to these parameters: [Na+]p is very sensitive to ΔTBW and moderately sensitive to ΔE, and is modulated by TBW. For example, for a person with 50L TBW, a net increase of 1L water lowers [Na+]p by 3.2 mEq/L, but for a person with 25L TBW it lowers [Na+]p by 6.3 mEq/L (assuming initial [Na+]p is 140 mEq/L). In each case, a loss of 159 mEq of sodium plus potassium (roughly equivalent to 1.5 teaspoons of table salt) would be required to produce the same effect as the net increase of 1L water. The present review demonstrates why fluid overload predominates over electrolyte loss in the aetiology of exercise-associated hyponatraemia (EAH), and why the excretion of electrolyte-dilute urine is highly effective in correcting EAH (nonetheless, loss of sodium and potassium is significant in long events in warm weather). Sports drinks will, if overconsumed, result in hyponatraemia. Administration of a sports drink to an athlete with fluid overload hyponatraemia further lowers [Na+]p and increases fluid overload. Administration of either a sports drink or normal (0.9%) saline increases fluid overload. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Are Large Amounts of Sodium Stored in an Osmotically Inactive Form During Sodium Retention? Balance Studies in Freely Moving Dogs," published in the previous issue.

The Huai River and Qingling Mountain divide (H-Q) divide China into north and south with respect to public policies for building construction and operation practises. China's building energy efficiency standard mandates that air exchange rates be 0.5 h − 1 north of the H-Q divide and 1 h − 1 south of the divide. China's heating policy allows space heating systems only north of the H-Q divide. Consequently, indoor temperature and humidity differ considerably between north and south. A theoretical model using indoor temperature, humidity, and air change rate was developed to predict indoor formaldehyde concentrations. Data for 39 cities were obtained from 42 studies. There was good agreement between the literature and modelling in a theoretical reference room. The United States Environmental Protection Agency (U.S.EPA) model was applied to estimate cancer risk from formaldehyde exposure indoors. The median indoor formaldehyde concentration for renovation ever from 2002 to 2015 in Chinese cities was 125 μg/m 3 , which is higher than the WHO threshold, 100 μg/m 3 . The median indoor formaldehyde concentrations in the north were higher than in the south (0.5 times higher for dwellings renovated within the past year and 0.2 times higher for renovation ever), driven by the much higher northern winter concentrations (40–1320%). The U.S.EPA model predicts that the lifetime formaldehyde related cancer risk for people living north of the H-Q divide is 1.2 times greater than for people living south. This can be partly explained by greater indoor exposure to formaldehyde for Chinese living north of the H-Q divide. [ABSTRACT FROM AUTHOR]

The author reflects on the study which examines the effects of ibuprofen on serum electrolyte concentrations after an ultradistance running race. He refers the findings of the study to the previous studies which shows that the more an athlete weighs at end of an event with his/her weight at the start, the lower is the [Na+]p. He rejected the study's conclusion which states that weight gain does not put an individual at risk for hyponatremia.

The last two decades have witnessed rapid urbanization and economic growth accompanied by severe indoor air pollution of volatile organic compounds (VOCs) in China. However, indoor VOC pollution across China has not been well characterized and documented. This study is a systematic review of field measurements of eight target VOCs (benzene, toluene, xylenes, acetaldehyde, p‐dichlorobenzene, butadiene, trichloroethylene, and tetrachloroethylene) in residences, offices, and schools in China from 2000 to 2021. The results show that indoor pollution of benzene, toluene, and xylenes has been more serious in China than in other countries. Spatiotemporal distribution shows lower indoor VOC levels in east and south‐east regions and a declining trend from 2000 to 2021. Moving into a dwelling more than 1 year after decoration and improving ventilation could significantly reduce exposure to indoor VOCs. Reducing benzene exposure is urgently needed because it is associated with greater health risks (4.5 × 10−4 for lifetime cancer risk and 8.3 for hazard quotient) than any other VOCs. The present study enriches the database of indoor VOC levels and provides scientific evidence for improving national indoor air quality standards as well as estimating the attributable disease burden caused by VOCs in China. [ABSTRACT FROM AUTHOR]

Exposure to volatile organic compounds (VOCs) indoors is thought to be associated with several adverse health effects. However, we still lack concentration–response (C‐R) relationships between VOC levels in civil buildings and various health outcomes. For this paper, we conducted a systematic review and meta‐analysis of observational studies to summarize related associations and C‐R relationships. Four databases were searched to collect all relevant studies published between January 1980 and December 2017. A total of 39 studies were identified in the systematic review, and 32 of these were included in the meta‐analysis. We found that the pooled relative risk (RR) for leukemia was 1.03 (95% CI: 1.01–1.05) per 1 μg/m3 increase of benzene and 1.25 (95%CI: 1.14–1.37) per 0.1 μg/m3 increase of butadiene. The pooled RRs for asthma were 1.08 (95% CI: 1.02–1.14), 1.02 (95% CI: 1.00–1.04), and 1.04 (95% CI: 1.02–1.06) per 1 μg/m3 increase of benzene, toluene, and p‐dichlorobenzene, respectively. The pooled RR for low birth weight was 1.12 (95% CI: 1.05–1.19) per 1 μg/m3 increase of benzene. Our findings provide robust evidence for associations between benzene and leukemia, asthma, and low birth weight, as well as for health effects of some other VOCs. [ABSTRACT FROM AUTHOR]

During 2010‐2012, we surveyed 40,010 3‐ to 6‐year‐old children in seven Chinese cities (Beijing, Taiyuan, Urumqi, Shanghai, Nanjing, Changsha, and Chongqing). Their parents reported information on household renovation, including the timing of renovation and the choice of materials for walls and floors in the child's room, and the incidence of their child's rhinitis. Multivariate and two‐level (city‐child) logistic regression analyses yielding adjusted odds ratios (AOR) with 95% confidence intervals were performed. Sensitivity analyses stratifying data for location and economic level were also performed. About 48.0% of the children had ever had allergic rhinitis, 41.2% had current allergic rhinitis, and 9.0% had had doctor‐diagnosed rhinitis. Exposure to household renovation during early lifetime (birth to 1‐year‐old) had an AOR of 1.43 (1.04‐1.9) for allergic rhinitis. The incidence of allergic rhinitis was significantly different in children exposed to different floor and wall covering materials. Floor or wall covering material composed of organic materials significantly increased the risk of childhood allergic rhinitis compared with tile flooring or lime wall covering. Oil paint had an AOR of 1.66 (1.28‐2.14) for diagnosed rhinitis compared with lime wall covering. Adding new furniture the year before pregnancy was associated with an AOR of 1.18 (1.10‐1.27) and 1.18 (1.11‐1.25) for lifetime and current rhinitis. Solid wood or tiles/ceramic as floor materials, and using wallpaper, oil paint, or emulsion panels as wall materials were risk factors for doctor‐diagnosed rhinitis. Sensitivity analyses showed that children living in southern or higher economic level China cities were more likely to have allergic rhinitis with household renovation. [ABSTRACT FROM AUTHOR]

It is difficult to evaluate long‐term ventilation and indoor‐outdoor temperature variation on‐site in the birth residence so as to investigate their associations with learning capacity from childhood through adolescence. Here, we conducted a questionnaire‐based retrospective cohort study in ten schools from two northeast China cities with warm summers and severe cold winters when residences had very low air exchange rates. Scores for Chinese, Mathematics, and English in the final exams of the summer semester in June 2018 were collected to evaluate learning capacity. We surveyed 6238 students aged 14.7 (SD: 2.1) years old. Using the 2nd quarter (April‐May‐June) birth as reference, 4th quarter (October‐November‐December) birth consistently was significantly associated with lower scores in Chinese in bivariate (β, 95%CI: −3.2, −4.3 to −2.0) and multivariate (−1.8, −2.4 to −0.8) linear regression analyses. Stratified sub‐analyses showed significant associations for male (−2.4, −3.7 to −1.1), urban (−2.4, −3.4 to −1.4), and primary students (−2.9, −4.5 to −1.4). Since household ventilation and indoor‐outdoor temperature variation had great differences between the 2nd and 4th quarter of year, our results suggest that these two factors in the birth residence could be associated with learning capacity in childhood, especially for male and primary students in northeast China. [ABSTRACT FROM AUTHOR]

Purpose: In the past 60 years, the prevalences of asthma and allergy among children have increased around the world. Neither genetic nor outdoor environmental factors can explain this increase. Methods: We performed a cross-sectional study of 7366 children in Tianjin, China, on associations of home environment and lifestyles with asthma and allergy. Results: The prevalences of diagnosed asthma, rhinitis and eczema among 0- to 8-year-old children in the Tianjin area were 4%, 9% and 39%. Home environment and lifestyle, together with infections, were strong risk factors. For asthma and allergy, the population attributable fraction (PAF) due to modern floors and wall coverings (i.e., laminated wooden floors and painted walls compared to tile floors and lime-coated walls) was 22%. Window condensation in winter and air conditioner use in summer, both of which are proxies for less ventilation, accounted for 7–17% of rhinitis and eczema. Cesarean delivery accounted for 10% of eczema symptoms. We developed a modern life index from appropriate home characteristics and lifestyle and food consumption habits and found it to have a clear dose–response relationship with asthma and allergy in Tianjin children. Conclusions: The results indicate that a "modern" home environment together with a modern lifestyle is associated with increased prevalences of asthma and allergies among children. Appropriate indoor environmental interventions and education of children's caregivers are important in the management of childhood asthma and allergy. [ABSTRACT FROM AUTHOR]

Objectives: We investigated patterns of multimorbidities among asthma, allergies, and respiratory illnesses in preschool children. We investigated multimorbidities of lifetime asthma, allergic rhinitis, eczema, food allergy, pneumonia, and ear infections; and multimorbidities of current (in the last year before the survey) wheeze, dry cough, rhinitis, eczema, and common cold during childhood. We further analyzed whether prevalences of these multimorbidities were due to chance.Methods: A cross-sectional study was conducted in 72 kindergartens of Shanghai, China. Parents of preschool children were surveyed with a modified ISAAC questionnaire. Observed prevalences (OPs), expected prevalences (EPs), absolute excess comorbidities (AECs), and relative excess comorbidities (RECs) of various combinations of illnesses were calculated to indicate whether the combined illnesses were related.Results: We analyzed questionnaires for children aged 4–6 years, whose 13,335 questionnaires were the majority of the total 15,266 returned questionnaires (response rate: 85.3%). The studied illnesses were common. For children who had more than three lifetime or current illnesses, OPs tended to be higher than EPs. Most OPs and EPs were higher in boys than in girls, and were higher in children with a family history of atopy (FHA) than in children without FHA. AECs and RECs between boys and girls as well as between children with and without FHA were substantially different.Conclusions: Our findings suggest that multimorbidities among childhood asthma, allergies, and respiratory illnesses are likely not random, but rather share etiology. Specific patterns of childhood asthma multimorbidities perhaps differ between boys and girls and between children with and without FHA. [ABSTRACT FROM PUBLISHER]

Objectives: We investigated associations of breastfeeding (BF) durations and patterns and of timing of other dietary introductions with prevalence of asthma, wheeze, hay fever, rhinitis, pneumonia, and eczema among preschool children.Methods: During April 2011-April 2012, we conducted a cross-sectional study in 72 kindergartens from five districts of Shanghai, China and obtained 13,335 questionnaires of children 4–6-years-old. We used multiple logistic regression models to evaluate the target associations.Results: Compared to children who were never BF, children who were exclusively breastfed 3–6 months had the lowest risk of asthma (adjusted odds ratio and 95% confidence interval: 0.81, 0.72–0.91) and wheeze (0.93, 0.87–0.99); and exclusive BF >6 months was significantly associated with a reduced risk of hay fever (0.93, 0.89–0.97), rhinitis (0.97, 0.94–0.99), pneumonia (0.97, 0.94–0.99), and eczema (0.96, 0.93–0.99). No significant associations were found between time when fruits or vegetables were introduced and the studied diseases. Associations were independent of the child's sex and parent's ownership of the current residence. Longer duration BF was only significantly protective when there was no family history of atopy.Conclusions: This study suggests that heredity, but not sex and socioeconomic status, may negatively impact the effect of BF on childhood airway and allergic diseases. Our findings support China's national recommendation that mothers provide exclusive BF for the first four months, and continue partial BF for more than 6 months. [ABSTRACT FROM AUTHOR]

Background: The prevalence of asthma among Shanghai children has increased over time. This increase might be associated with changes in environmental exposures. Investigation of the time-trend of asthma and current prevalences is essential to understanding the causes. Objective: To estimate the current prevalences of asthma, allergies and other respiratory symptoms among Shanghai preschool children, and to investigate the time-trend of childhood asthma prevalence of from 1990 to 2011. Methods: From April 2011 to April 2012, the CCHH (China, Children, Homes, Health) cross-sectional study was conducted in Shanghai. Questionnaires were distributed to 17,898 parents or guardians of preschool children from 72 kindergartens in 5 districts. Previous similar studies were also summarized by a systematic literature review. Results: From a total of 14,884 questionnaires for 3–7 year old children, prevalences of the following diseases and symptoms were calculated: asthma 10.2%, wheeze (ever) 28.1%, pneumonia (ever) 33.5%, otitis media 11.0%, rhinitis (ever) 54.1%, hay fever 12.2%, eczema (ever) 22.7%, and food allergy 15.7%. Urban children had higher prevalences of most symptoms than suburban children. The prevalence of asthma has increased significantly, almost five-fold, from 2.1% in 1990 to 10.2% in the present study. The prevalence of asthma in boys was higher than in girls in the present study and in all reviewed studies. Conclusions: Asthma, allergy and airway symptoms are common among preschool children in Shanghai. The prevalence of childhood asthma in Shanghai has increased rapidly from 1990 to 2011. [ABSTRACT FROM AUTHOR]

• This study is the first to investigate indoor formaldehyde contribution to ambient. • Residential building materials are a significant source of ambient formaldehyde. • The share of residential emissions to 81 anthropogenic sources was 6.66% (rank 6th). • Residential emission intensities were higher in more urbanized areas. • Building density, building materials, T and RH are influencing factors of emission. This study investigates the contribution of formaldehyde from residential building materials to ambient air in mainland China. Based on 265 indoor field tests in 9 provinces, we estimate that indoor residential sources are responsible for 6.66% of the total anthropogenic formaldehyde in China's ambient air (range for 31 provinces: 1.88–18.79%). Residential building materials rank 6th among 81 anthropogenic sources (range: 2nd–10th for 31 provinces). Emission intensities show large spatial variability between and within regions due to different residential densities, emission characteristics of building materials, and indoor thermal conditions. Our findings indicate that formaldehyde from the indoor environment is a significant source of ambient formaldehyde, especially in urban areas. This study will help to more accurately evaluate exposure to ambient formaldehyde and its related pollutants, and will assist in formulating policies to protect air quality and public health. [ABSTRACT FROM AUTHOR]

The article summarizes the most current information on the prevalence, nature and treatment of exercise-associated hyponatremia (EAH) for medical personnel, athletes and the public to help prevent morbidity and mortality associated with the disorder, as compiled by a panel of 18 international experts at the Second International Exercise-Associated Hyponatremia (EAH) Consensus Development Conference in New Zealand in November 2007. The panel represented seven countries and eight specialties related to exercise physiology, sports medicine, water metabolism and body fluid homeostatis. Included in the summary are EAH classification, treatment protocols and dissemination of advice.