Effect of fatty acid profiles in varying recipes of ready-to-use therapeutic foods on neurodevelopmental and clinical outcomes of children (6-59 months) with severe wasting: a systematic review.

CONTEXT: In 2020, 13.6 million children under 5 years suffered from severe acute malnutrition (SAM)/wasting. Standard ready-to-use therapeutic foods (RUTFs) improve polyunsaturated fatty acid (PUFA) status but contain suboptimal amounts of omega-3 (n-3) PUFAs with unbalanced n-6-to-n-3 PUFA ratios. OBJECTIVES: The aim was to compare the effects of RUTFs with different essential fatty acid contents on PUFA status, neurodevelopmental, and clinical outcomes (mortality, comorbidities, and recovery) of children with severe wasting. DATA SOURCES: Twelve databases, trial repositories, and article references with no publication limitations. DATA EXTRACTION: Ten studies from randomized, quasi, and cluster-randomized controlled trials providing RUTFs as home treatment to children 6-59 months with SAM/wasting were included. DATA ANALYSIS: Plasma phospholipid eicosapentaenoic acid content was higher in children receiving RUTF with altered essential fatty acid contents compared with standard RUTF (0.20 [0.15-0.25], P < 0.00001). Docosahexaenoic acid (DHA) status only improved in children receiving RUTF with added fish oil (0.33 [0.15-0.50], P = 0.0003). The Malawi Developmental Assessment tool (MDAT) global development and problem-solving assessment scores were higher in global assessment and gross motor domains in children receiving added fish oil compared with standard formulation (0.19 [0.0-0.38] and 0.29 [0.03-0.55], respectively). Children receiving high-oleic-acid RUTF (lowering the n-6:n-3 PUFA ratio of the RUTF) with or without fish oil had significantly higher scores in social domains compared with those receiving the standard formulation (0.16 [0.00-0.31] and 0.24 [0.09-0.40]). Significantly higher mortality risk was found in children receiving a standard formulation compared with RUTF with a lower n-6:n-3 PUFA ratio (0.79 [0.67-0.94], P = 0.008). CONCLUSION: Although lowering n-6:n-3 PUFA ratios did not increase plasma DHA, it improved specific neurodevelopmental scores and mortality due to lower linoleic acid (high-oleic-acid peanuts), higher alpha-linolenic acid (altered oil), or both. Additional preformed n-3 long-chain PUFAs (fish oil) with RUTF improved the children's DHA status, neurodevelopmental outcomes, and weight-for-height z score. More research is needed regarding cost, availability, stability, acceptability, and the appropriate amount of n-3 long-chain PUFAs required in RUTFs for the best clinical outcomes. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42022303694.

Effectiveness and safety of tenofovir alafenamide in children and adolescents living with HIV: a systematic review.

INTRODUCTION: Tenofovir alafenamide (TAF) is approved for paediatric use in fixed-dose combination tablets, but efficacy and safety data in children are limited. We conducted a systematic review on the efficacy/effectiveness and safety of TAF in infants, children and adolescents living with HIV. METHODS: We searched MEDLINE, Embase, the Cochrane Library, clinical trial registries, reference lists and relevant conferences to identify literature published January 2009-March 2021. We included clinical trials and observational studies assessing the efficacy/effectiveness or safety of TAF through ≥6 months of treatment in participants aged 0-19 years. RESULTS AND DISCUSSION: Overall 3626 abstracts and 371 full papers were screened. Four single-arm, innovator-funded trials (341 participants) and a pooled analysis of those trials were identified. All four trials included treatment-experienced and virally suppressed children or adolescents. One trial also included treatment-naïve adolescents with baseline viral load >1000 copies/ml. The risk of bias was rated as low in one study and unclear in the other three owing to missing data on study design (all conference presentations). At 48 weeks, 92% (46/50) of treatment-naïve participants were virally suppressed (one trial). Among treatment-experienced participants with viral load at 48 weeks, 214 of 224 participants were virally suppressed. Across the studies, one grade 3/4 adverse event was considered drug-related (intermediate uveitis). There were three discontinuations for adverse events (grade 2 anxiety and insomnia, grade 1 iridocyclitis [drug-related] and grade 1 pulmonary tuberculosis [unrelated to treatment]). One accidental death occurred across the four studies. In the pooled analysis of 223 participants, the median change in bone mineral density z-score (height- and age-adjusted) from baseline to 48 weeks was -0.12 (interquartile range [IQR] -0.46, 0.17) to 0.05 (IQR not reported) for spine, and -0.09 (IQR -0.33, 0.07) to 0.09 (IQR not reported) for total body less head. Weight-for-age z-scores increased by 0.25 from baseline to 48 weeks. CONCLUSIONS: Four single-arm trials were identified in this systematic review, with initial evidence suggesting good viral suppression and no obvious safety concerns in children and adolescents on TAF-containing regimens over 24-48 weeks. However, further comparative and longer-term safety data are needed in children and adolescents, including on weight and metabolic changes.

Effectiveness and safety of dolutegravir and raltegravir for treating children and adolescents living with HIV: a systematic review.

INTRODUCTION: Globally about 1.7 million children were living with HIV in 2020. Two integrase strand transfer inhibitors, dolutegravir and raltegravir, are increasingly used in children. We conducted a systematic review to assess the effectiveness and safety of dolutegravir and raltegravir in children and adolescents living with HIV, aged 0-19 years. METHODS: Sources included MEDLINE, Embase, the Cochrane Library, clinical trial registries, abstracts from key conferences and reference list searching. Observational studies and clinical trials published January 2009-March 2021 were eligible. Outcomes included efficacy/effectiveness (CD4 counts and viral load) and/or safety outcomes (mortality, grade 3/4 adverse events and treatment discontinuation) through 6 months or more post-treatment initiation. Risk of bias was assessed using previously published tools appropriate for the study design. Narrative syntheses were conducted. RESULTS AND DISCUSSION: In total, 3626 abstracts and 371 papers were screened. Eleven studies, including 2330 children/adolescents, reported data on dolutegravir: one randomized controlled trial (RCT; low risk of bias), one single-arm trial (unclear risk of bias) and nine cohort studies (three low risk of bias, two unclear risk and four high risk). Ten studies, including 649 children/adolescents receiving raltegravir, were identified: one RCT (low risk of bias), one single-arm trial (low risk of bias) and eight cohort studies (four low risk of bias, three unclear risk and one high risk). Viral suppression levels in children/adolescents at 12 months were high (>70%) in most studies assessing dolutegravir (mostly second- or subsequent-line, or mixed treatment lines), and varied from 42% (5/12) to 83% (44/53) at 12 months in studies assessing raltegravir (mostly second- or subsequent-line). Across all studies assessing dolutegravir or raltegravir, grade 3/4 adverse events (clinical and/or laboratory) were reported in 0-50% of subjects, few resulted in discontinuation, few were drug related and no deaths were attributed to either drug. CONCLUSIONS: These reassuring findings suggest that dolutegravir and raltegravir are effective and safe as preferred regimens in children and adolescents living with HIV. With the rollout of dolutegravir in paediatric populations already underway, it is critical that data are collected on safety and effectiveness in infants, children and adolescents, including on longer-term outcomes, such as weight and metabolic changes.

The health policy response to COVID-19 in Malawi.

Malawi declared a state of national disaster due to the COVID-19 pandemic on 20th March 2020 and registered its first confirmed coronavirus case on the 2 April 2020. The aim of this paper was to document policy decisions made in response to the COVID-19 pandemic from January to August 2020. We reviewed policy documents from the Public Health Institute of Malawi, the Malawi Gazette, the Malawi Ministry of Health and Population and the University of Oxford Coronavirus Government Response Tracker. We found that the Malawi response to the COVID-19 pandemic was multisectoral and implemented through 15 focused working groups termed clusters. Each cluster was charged with providing policy direction in their own area of focus. All clusters then fed into one central committee for major decisions and reporting to head of state. Key policies identified during the review include international travel ban, school closures at all levels, cancellation of public events, decongesting workplaces and public transport, and mandatory face coverings and a testing policy covering symptomatic people. Supportive interventions included risk communication and community engagement in multiple languages and over a variety of mediums, efforts to improve access to water, sanitation, nutrition and unconditional social-cash transfers for poor urban and rural households.

Household air pollution and under-five mortality in sub-Saharan Africa: an analysis of 14 demographic and health surveys.

BACKGROUND: Globally, over four million deaths are attributed to exposure to household air pollution (HAP) annually. Evidence of the association between exposure to HAP and under-five mortality in sub-Saharan Africa (SSA) is insufficient. We assessed the association between exposure to HAP and under-five mortality risk in 14 SSA countries. METHODS: We pooled Demographic and Health Survey (DHS) data from 14 SSA countries (N = 164376) collected between 2015 and 2018. We defined exposure to HAP as the use of biomass fuel for cooking in the household. Under-five mortality was defined as deaths before age five. Data were analyzed using mixed effects logistic regression models. RESULTS: Of the study population, 73% were exposed to HAP and under-five mortality was observed in 5%. HAP exposure was associated with under-five mortality, adjusted odds ratio (OR) 1.33 (95% confidence interval (CI) [1.03-1.71]). Children from households who cooked inside the home had higher risk of under-five mortality compared to households that cooked in separate buildings [0.85 (0.73-0.98)] or outside [0.75 (0.64-0.87)]. Lower risk of under-five mortality was also observed in breastfed children [0.09 (0.05-0.18)] compared to non-breastfed children. CONCLUSIONS: HAP exposure may be associated with an increased risk of under-five mortality in sub-Saharan Africa. More carefully designed longitudinal studies are required to contribute to these findings. In addition, awareness campaigns on the effects of HAP exposure and interventions to reduce the use of biomass fuels are required in SSA.

Levels of knowledge regarding malaria causes, symptoms, and prevention measures among Malawian women of reproductive age.

BACKGROUND: Malawi is a malaria-endemic country and approximately 6 million cases are reported annually. Improving knowledge of malaria causes and symptoms, and the overall perception towards malaria and its preventive measures is vital for malaria control. The current study investigated the levels of knowledge of the causes, symptoms and prevention of malaria among Malawian women. METHODS: Data from the 2017 wave of the Malawi Malaria Indicator Survey (MMIS) were analysed. In total, 3422 women of reproductive age (15-49 years) were sampled and analysed. The levels of women's knowledge about: (1) causes of malaria; (2) symptoms of malaria; and, (3) preventive measures were assessed. The tertiles of the composite score were used as the cut-offs to categorize the levels of knowledge as 'low', 'medium' and 'high'. Multinomial logistic regression models were constructed to assess the independent factors while taking into account the complex survey design. RESULTS: Approximately 50% of all respondents had high levels of knowledge of causes, symptoms and preventive measures. The high level of knowledge was 45% for rural women and 55% for urban dwellers. After adjusting for the a wide range of factors, women of age group 15-19 years adjusted odds ratio ((aOR): 2.58; 95% Confidence Interval (CI) 1.69-3.92), women with no formal education (aOR: 3.73; 95% CI 2.20-6.33), women whose household had no television (aOR: 1.50; 95% CI 1.02-2.22), women who had not seen/heard malaria message (aOR: 1.53; 95% CI 1.20-1.95), women of Yao tribe (aOR: 1.95; 95% CI 1.10-3.46), and women from rural areas had low levels of knowledge about the causes of malaria, symptoms of malaria and preventive measures. Additionally, the results also showed that women aged 15-19 years (beta [ß] = - 0.73, standard error [SE] = 0.12); P < .0001, women with no formal education (ß = - 1.17, SE = 0.15); P < .0001, women whose household had no radio (ß = - 0.15, SE = 0.0816); P = 0.0715 and women who had not seen or heard malaria message (ß = - 0.41, SE = 0.07); P < .0001 were likely to have a lower knowledge score. CONCLUSIONS: The levels of malaria knowledge were reported to be unsatisfactory among adult women, underscoring the need to scale up efforts on malaria education. Beside insecticide-treated bed nets (ITNs) and prompt diagnosis, malaria can be best managed in Malawi by increasing knowledge of malaria causes, and symptoms especially for younger women, women with no formal education, women whose households have no media, women from Yao tribes, and rural dwellers.

Multilevel analysis of factors associated with unmet need for family planning among Malawian women.

BACKGROUND: Malawi has a high fertility rate which is also characterized by a relatively high prevalence of unmet need for contraception. However, little is known about the influence of individual- and community- level characteristics on unmet need in Malawi. This study examined the individual- and community- level factors associated with unmet need for family planning (FP) among Malawian women. METHODS: Data from the 2015-16 Malawi demographic and health survey were used to analyze 15, 931 women. The association between individual- and community- level factors and unmet need was assessed using multilevel binary logistic regression models. RESULTS: The prevalence of total unmet need was 21.0%. Women aged ≥35 years were more likely to have total unmet need [adjusted odds ratio (aOR) = 1.19, 95% confidence interval (CI) = 1.04-1.35] compared with those aged 15-24 years. Women who were married [aOR = 0.41, 95% CI = 0.35-0.48], and those employed [aOR = 0.78, 95% CI = 0.71-0.85] were associated with less likelihood of having total unmet need compared with unmarried, and unemployed women, respectively. At community-level, women from communities with a high percentage of women from rich households [aOR = 0.81, 95% CI = 0.67-0.96], and those from communities with a middle and high percentage of educated women [aOR = 0.86, 95% CI = 0.76-0.96 and aOR = 0.81, 95% CI = 0.70-0.93, respectively] were less likely to have total unmet need for FP compared with those from communities with low percentages of rich and educated women, respectively. The proportional change in variance showed that about 36.0% of total variations in the odds of unmet need across the communities were explained by both individual- and community-level factors. Moreover, the intraclass correlation showed that about 3.0% of the total variation remained unexplained even after controlling for both individual- and community-level factors. CONCLUSION: Both individual- and community- level factors influenced unmet need for FP in Malawi. Public health practitioners should conduct community profiling and consider individual and community factors when designing FP programs.

Nasal DNA methylation profiling of asthma and rhinitis.

BACKGROUND: Epigenetic signatures in the nasal epithelium, which is a primary interface with the environment and an accessible proxy for the bronchial epithelium, might provide insights into mechanisms of allergic disease. OBJECTIVE: We aimed to identify and interpret methylation signatures in nasal epithelial brushes associated with rhinitis and asthma. METHODS: Nasal epithelial brushes were obtained from 455 children at the 16-year follow-up of the Dutch Prevention and Incidence of Asthma and Mite Allergy birth cohort study. Epigenome-wide association studies were performed on children with asthma, rhinitis, and asthma and/or rhinitis (AsRh) by using logistic regression, and the top results were replicated in 2 independent cohorts of African American and Puerto Rican children. Significant CpG sites were related to environmental exposures (pets, active and passive smoking, and molds) during secondary school and were correlated with gene expression by RNA-sequencing (n = 244). RESULTS: The epigenome-wide association studies identified CpG sites significantly associated with rhinitis (n = 81) and AsRh (n = 75), but not with asthma. We significantly replicated 62 of 81 CpG sites with rhinitis and 60 of 75 with AsRh, as well as 1 CpG site with asthma. Methylation of cg03565274 was negatively associated with AsRh and positively associated with exposure to pets during secondary school. DNA methylation signals associated with AsRh were mainly driven by specific IgE-positive subjects. DNA methylation related to gene transcripts that were enriched for immune pathways and expressed in immune and epithelial cells. Nasal CpG sites performed well in predicting AsRh. CONCLUSIONS: We identified replicable DNA methylation profiles of asthma and rhinitis in nasal brushes. Exposure to pets may affect nasal epithelial methylation in relation to asthma and rhinitis.

Timing of secondhand smoke, pet, dampness or mould exposure and lung function in adolescence.

BACKGROUND: The relevance of timing of exposure in the associations of secondhand tobacco smoke (SHS), pets, and dampness or mould exposure with lung function is unclear. We investigated the relevance of timing of these exposures for lung function in adolescence. METHODS: We used data from participants of the Dutch Prevention and Incidence of Asthma and Mite Allergy (PIAMA) cohort with spirometric measurements at ages 12 and 16 years (n=552). Data on residential exposure to SHS, pets, and dampness or mould were obtained by repeated parental questionnaires. We characterised timing of exposure through longitudinal patterns using latent class growth modelling and assessed associations of these patterns with FEV1 and FVC at ages 12 and 16 and FEV1 and FVC growth between ages 12 and 16 using linear regression models. RESULTS: Childhood SHS exposure was associated with reduced FEV1 growth/year (95% CI) (-0.34% (-0.64% to -0.04%)). Late childhood and early life pet exposure was associated with increased FEV1 growth (0.41% (0.14% to 0.67%)) and reduced FVC growth (-0.28% (-0.53% to -0.03%)), respectively, compared with very low exposure. Early life dampness or mould exposure was associated with reduced lung function growth. All time windows of SHS exposure tended to be associated with lower attained lung function and pet exposure tended to be associated with higher FEV1. CONCLUSION: SHS exposure during childhood could lead to reduced lung function growth and lower attained lung function in adolescence. While pet exposure in late childhood may not adversely affect lung function, early childhood pet exposure may slow down FVC growth in adolescence.

Determinants of timely initiation of breast milk and exclusive breastfeeding in Malawi: a population-based cross-sectional study.

Background: Breastfeeding practices such as early initiation of breast milk and exclusive breastfeeding are key to the reduction of childhood morbidity and mortality. Despite the importance of these practices, rates of timely initiation of breastfeeding and exclusive breastfeeding remain suboptimal in many sub-Saharan countries. This study aimed to examine the determinants of early initiation of breastfeeding and exclusive breastfeeding in the first 5 months in Malawi. Methods: This study used the 2015-16 Malawi Demographic and Health Survey data. A total of 6351 children born during the last 24 months and 1619 children aged 0-5 months at the time of the survey were analyzed for early initiation of breastfeeding and exclusive breastfeeding outcomes, respectively. Socio-demographic and socio-economic factors including individual, household and community-level factors were tested for association with early initiation of breastfeeding and exclusive breastfeeding using logistic regression models. Results: The proportion of timely initiation of breast milk and exclusive breastfeeding were 76.9 and 61.2%, respectively. Delivering at a health facility (adjusted odds ratio [aOR] 1.77, 95% confidence interval [CI] 1.10, 2.87), vaginal delivery (aOR 3.15, 95% CI 2.40, 4.13), and singleton births (aOR 1.96, 95% CI 1.20, 3.21) were independent factors associated with the increased likelihood of timely initiation of breastfeeding. Age of children was associated with increased odds of exclusive breastfeeding, with children aged 3-5 months being less likely to be exclusively breastfed (aOR 0.24, 95% CI 0.18, 0.31). Conclusions: Healthcare providers and programs aimed at increasing rates of early initiation of breastfeeding should take into consideration women at risk such as those giving birth through caesarean section, giving birth at home, and having multiple births. Further, women with children aged 3-5 months should be targeted with health promotion interventions for exclusive breastfeeding.

Role of timing of exposure to pets and dampness or mould on asthma and sensitization in adolescence.

BACKGROUND: Pet and dampness or mould exposure are considered risk factors for asthma and sensitization. It is unclear whether timing of exposure to these factors is differentially associated with asthma risk and sensitization in adolescence. OBJECTIVE: We investigated the role of timing of pet and dampness or mould exposure in asthma and sensitization in adolescence. Understanding this role is essential to build targeted prevention strategies. METHODS: We used data from 1871 participants of the Dutch Prevention and Incidence of Asthma and Mite Allergy (PIAMA) cohort. Residential exposure to pets, dampness or mould was assessed by repeated parental questionnaires. We used asthma data from the 17-year questionnaire and sensitization data from the 16-year medical examination. We characterized timing using longitudinal exposure patterns from pregnancy till age 17 using longitudinal latent class growth modelling. We used logistic regression models to analyse associations of exposure patterns with asthma at age 17 and sensitization at age 16. RESULTS: For none of the time windows, exposure to pets and dampness or mould was associated with asthma at age 17, but a lower sensitization risk at age 16 was suggested, for example the odds ratio (95% confidence interval) for sensitization was 0.63 (0.35-1.11) and 0.69 (0.44-1.08) for early life and persistently high pet exposure, respectively, compared with very low exposure. An inverse association was also suggested for sensitization and moderate early childhood dampness or mould exposure (0.71 [0.42-1.19]). CONCLUSION AND CLINICAL RELEVANCE: Different timing of pet and dampness or mould exposure was not associated with asthma, but lower risk of sensitization in adolescence was suggested, which could be partly attributable to reversed causation. Current findings are not sufficient to recommend pet avoidance to prevent allergic disease. More prospective studies are needed to obtain insights that can be used in clinical practice.

Considerations in the use of different spirometers in epidemiological studies.

BACKGROUND: Spirometric lung function measurements have been proven to be excellent objective markers of respiratory morbidity. The use of different types of spirometers in epidemiological and clinical studies may present systematically different results affecting interpretation and implication of results. We aimed to explore considerations in the use of different spirometers in epidemiological studies by comparing forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) measurements between the Masterscreen pneumotachograph and EasyOne spirometers. We also provide a correction equation for correcting systematic differences using regression calibration. METHODS: Forty-nine volunteers had lung function measured on two different spirometers in random order with at least three attempts on each spirometer. Data were analysed using correlation plots, Bland and Altman plots and formal paired t-tests. We used regression calibration to provide a correction equation. RESULTS: The mean (SD) FEV1 and FVC was 3.78 (0.63) L and 4.78 (0.63) L for the Masterscreen pneumotachograph and 3.54 (0.60) L and 4.41 (0.83) L for the EasyOne spirometer. The mean FEV1 difference of 0.24 L and mean FVC difference of 0.37 L between the spirometers (corresponding to 6.3 and 8.4% difference, respectively) were statistically significant and consistent between younger (< 30 years) and older volunteers (> 30 years) and between males and females. Regression calibration indicated that an increase of 1 L in the EasyOne measurements corresponded to an average increase of 1.032 L in FEV1 and 1.005 L in FVC in the Masterscreen measurements. CONCLUSION: Use of different types of spirometers may result in significant systematic differences in lung function values. Epidemiological researchers need to be aware of these potential systematic differences and correct for them in analyses using methods such as regression calibration.

Air pollution exposure and lung function until age 16 years: the PIAMA birth cohort study.

Evidence for the effects of air pollution exposure on lung function growth into adolescence is scarce. We investigated associations of air pollution exposure with lung function and lung function growth until age 16.We conducted both longitudinal (n=915) and cross-sectional (n=721) analyses of associations of air pollution exposure with forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) growth from ages eight to 16 and FEV1 and FVC at age 16. We estimated residential concentrations of nitrogen dioxide (NO2), "soot" and particulate matter (PMx, where x is the 50% cut-off aerodynamic diameter in µm) with diameters of <2.5 µm (PM2.5), <10 µm (PM10) and 2.5-10 µm (PMcoarse) during the preschool, primary school and secondary school time windows by land use regression models. Associations with (growth in) FEV1 and FVC were analysed by linear (mixed effects) regression.Higher air pollution exposure was associated with reduced FEV1 growth (e.g. adjusted difference -0.26% (95% CI -0.49 to -0.03%) per interquartile range increase in secondary school PM2.5) and lower FEV1 (adjusted difference -2.36% (95% CI -3.76 to -0.94%)), but was not adversely associated with FVC. Associations with FEV1 were stronger in boys than girls and were not modified by asthma status.Higher air pollution exposure may lead to increased airway obstruction, but not reduced lung volume in adolescence.

Maternal biomass smoke exposure and birth weight in Malawi: Analysis of data from the 2010 Malawi Demographic and Health Survey.

BACKGROUND: Use of biomass fuels has been shown to contribute to ill health and complications in pregnancy outcomes such as low birthweight, neonatal deaths and mortality in developing countries. However, there is insufficient evidence of this association in the Sub-Saharan Africa and the Malawian population. We, therefore, investigated effects of exposure to biomass fuels on reduced birth weight in the Malawian population. METHODS: We conducted a cross-sectional analysis using secondary data from the 2010 Malawi Demographic Health Survey with a total of 9124 respondents. Information on exposure to biomass fuels, birthweight, and size of child at birth as well as other relevant information on risk factors was obtained through a questionnaire. We used linear regression models for continuous birth weight outcome and logistic regression for the binary outcome. Models were systematically adjusted for relevant confounding factors. RESULTS: Use of high pollution fuels resulted in a 92 g (95% CI: -320.4; 136.4) reduction in mean birth weight compared to low pollution fuel use after adjustment for child, maternal as well as household characteristics. Full adjusted OR (95% CI) for risk of having size below average at birth was 1.29 (0.34; 4.48). Gender and birth order of child were the significant confounders factors in our adjusted models. CONCLUSIONS: We observed reduced birth weight in children whose mothers used high pollution fuels suggesting a negative effect of maternal exposure to biomass fuels on birth weight of the child. However, this reduction was not statistically significant. More carefully designed studies need to be carried out to explore effects of biomass fuels on pregnancy outcomes and health outcomes in general.

Lifetime secondhand smoke exposure and childhood and adolescent asthma: findings from the PIAMA cohort.

BACKGROUND: Secondhand smoke (SHS) exposure is a modifiable risk factor associated with childhood asthma. Associations with adolescent asthma and the relevance of the timing and patterns of exposure are unclear. Knowledge of critical windows of exposure is important for targeted interventions. METHODS: We used data until age 17 from 1454 children of the Dutch population-based PIAMA birth cohort. Residential SHS exposure was assessed through parental questionnaires completed at ages 3 months, 1-8 (yearly), 11, 14, and 17 years. Lifetime exposure was determined as; a) time window-specific exposure (prenatal, infancy, preschool, primary school, and secondary school); b) lifetime cumulative exposure; c) longitudinal exposure patterns using latent class growth modeling (LCGM). Generalized estimation equations and logistic regression were used to analyze associations between exposure and asthma at ages 4 to 17 years, adjusting for potential confounders. RESULTS: With all three methods, we consistently found no association between SHS exposure and asthma at ages 4 to 17 years e.g. adjusted overall odds ratio (95% confidence interval) 0.67 (0.41-1.12), 1.00 (0.66-1.51) and 0.67 (0.41-1.11) for prenatal maternal active smoking, infancy, and preschool school time window exposures, respectively. CONCLUSION: We assessed lifetime SHS exposure using different methods. Different timing and patterns of SHS exposure were not associated with an increased risk of asthma in childhood and adolescence in our study. More longitudinal studies could investigate effects of lifetime SHS exposure on asthma in adolescence and later life.