Prognostic factors associated with small for gestational age babies in a tertiary care hospital of Western Nepal: A cross-sectional study

BACKGROUND

Small for gestational age (SGA) is common among newborns in low-income countries like Nepal and has higher immediate mortality and morbidities.

OBJECTIVES

To study the prevalence and prognostic factors of SGA babies in Western Nepal.

METHODS

A cross-sectional study (November 2016-October 2017) was conducted in a tertiary care hospital in Western Nepal. Socio-demographic, lifestyle factors including diet, and exposures including smoking and household air pollution in mothers who delivered newborns appropriate for gestational age (AGA), SGA and large for gestational age (LGA) were recorded. Logistic regression was carried out to find the odds ratio of prognostic factors after adjusting for potential confounders.

RESULTS

Out of 4000 delivered babies, 77% (n = 3078) were AGA, 20.3% (n = 813) were SGA and 2.7% (n = 109) were LGA. The proportion of female-SGA was greater in comparison to male-SGA (n = 427, 52.5% vs n = 386, 47.5%). SGA babies were born to mothers who had term, preterm, and postterm delivery in the following proportions 70.1%, 19.3%, and 10.6%, respectively. The average weight gain (mean ± SD) by mothers in AGA pregnancies was 10.3 ± 2.4 kg, whereas in SGA were 9.3 ± 2.4 kg. In addition to low socioeconomic status (OR 1.9, 95% CI 1.1, 3.2), other prognostic factors associated with SGA were lifestyle factors such as low maternal sleep duration (OR 5.1, CI 3.6, 7.4) and monthly or less frequent meat intake (OR 5.0, CI 3.2, 7.8). Besides smoking (OR 8.8, CI 2.1, 36.3), the other major environmental factor associated with SGA was exposure to household air pollution (OR 5.4, 4.1, 6.9) during pregnancy. Similarly, some of the adverse health conditions associated with a significantly higher risk of SGA were anemia, oligohydramnios, and gestational diabetes.

CONCLUSIONS

SGA is common in Western Nepal and associated with several modifiable prognostic factors.

The burden of chronic respiratory diseases in adults in Nepal: A systematic review

While chronic lung disease causes substantial global morbidity and mortality, global estimates have primarily been based on broad assumptions. Specific country data from low-income countries such as Nepal are limited. This review assessed primary evidence on chronic respiratory disease burden among adults in Nepal. A systematic search was performed in June 2019 (updated May 2020) for studies through nine databases. High levels of heterogeneity deemed a narrative synthesis appropriate. Among 27 eligible studies identified, most were low-moderate quality with cross-sectional and retrospective study design. Chronic lung diseases identified were chronic obstructive pulmonary disease (COPD), asthma, bronchiectasis and restrictive lung diseases. Studies were categorised as: (i) community-based, (ii) hospital-based and (iii) comorbidity-related and disease burden. Reported disease prevalence varied widely (COPD, 1.67-14.3%; asthma, 4.2-8.9%). The prevalence of airflow obstruction was higher among rural dwellers (15.8%) and those exposed to household air pollution from domestic biomass burning as opposed to liquid petroleum gas users (Odds Ratio: 2.06). Several comorbidities, including hypertension and diabetes mellitus added to the disease burden. The review shows limited literature on lung disease burden in Nepal. Publications varied in terms of overall quality. Good quality research studies with prospective cohorts related to respiratory conditions are required.

Clinico-radiological Observations in Meconium Aspiration Syndrome

Introduction: To understand and report the prevalence of meconium aspiration syndrome and the clinico-radiological features in a tertiary care hospital of western Nepal. Methods: An observational study carried out for a year in 2014-15 in all babies with MAS. Clinical and radiological profiles of MAS in relation to gender, gestational age, mode of delivery, birth weight, Apgar score, thickness of meconium, age at admission and the immediate outcome were studied. Results: Out of 584 admitted newborns (male=389; female=186) during the study period, 78 (13.4%) had meconium aspiration syndrome with male: female ratio of 1.2:1. Majority of babies admitted to NICU had thick meconium [n=52 (66.7%)]. There was no statistical significant difference in various parameters such as Apgar score at 1 and 5 minutes, respiratory distress, birth asphyxia, duration of oxygen use, MAS severity and chest x-ray in those with thick MAS compared to thin. Among all newborns with MAS, 59% (n=46) had abnormal radiological findings with over two-folds in those with thick MAS (71.7%)] compared to thin (28%). Hyperinflation (47.8%), diffuse patchy infiltration (37%), consolidation (21.7%) collapse (8.7%), right lung fissure (6.5%) and pneumothorax (8.7%) were the abnormal radiological findings seen in MAS babies. The odds of having APGAR score at 1 minute at least 7 or more was twice unlikely in those having thick meconium compared to thin (P=0.02) Conclusions: Thick meconium is relatively common with more significant abnormal radiological findings and low Apgar score.

Clinico-radiological Observations in Meconium Aspiration Syndrome

INTRODUCTION

To understand and report the prevalence of meconium aspiration syndrome and the clinico-radiological features in a tertiary care hospital of western Nepal.

METHODS

An observational study carried out for a year in 2014-15 in all babies with MAS. Clinical and radiological profiles of MAS in relation to gender, gestational age, mode of delivery, birth weight, Apgar score, thickness of meconium, age at admission and the immediate outcome were studied.

RESULTS

Out of 584 admitted newborns (male=389; female=186) during the study period, 78 (13.4%) had meconium aspiration syndrome with male: female ratio of 1.2:1. Majority of babies admitted to NICU had thick meconium [n=52 (66.7%)]. There was no statistical significant difference in various parameters such as Apgar score at 1 and 5 minutes, respiratory distress, birth asphyxia, duration of oxygen use, MAS severity and chest x-ray in those with thick MAS compared to thin. Among all newborns with MAS, 59% (n=46) had abnormal radiological findings with over two-folds in those with thick MAS (71.7%)] compared to thin (28%). Hyperinflation (47.8%), diffuse patchy infiltration (37%), consolidation (21.7%) collapse (8.7%), right lung fissure (6.5%) and pneumothorax (8.7%) were the abnormal radiological findings seen in MAS babies. The odds of having APGAR score at 1 minute at least 7 or more was twice unlikely in those having thick meconium compared to thin (P=0.02) Conclusions: Thick meconium is relatively common with more significant abnormal radiological findings and low Apgar score.

Gestational Age Specific Postnatal Growth Curves for Singleton Babies in Tertiary Hospital of Western Nepal

Introduction: Measurement of birth weight (BW), crown heel length (CHL), head circumference (HC) and chest circumference used to assess the intrauterine growth of a baby vary with altitude, race, gender, socio economic status, maternal size, and maternal diseases. The study aimed to construct centile charts for BW, CHL and HC for new born at different gestational ages in western Nepal. Methods:  This was a descriptive cross sectional study done over a period of 15 months in a tertiary care hospital of western Nepal. BW, length, HC and CC were measured within 12-24 hours of birth. Gestational age was estimated from first day of last menstrual period, maternal ultrasonology and New Ballard’s scoring system. Microsoft 2007 Excel and SPSS-16 was used for data analysis. Cole’s Lambda Mu Sigma method was used for constructing centile curves. Results: Out of 2000 babies analysed, 1910 samples were used to construct smoothed intrauterine growth curve of BW, CHL, and HC from 33-42 weeks of gestation. 57.35% (1147) were male, mean gestational age was 38.13 ±2.44 weeks, where 21.5% were preterm and 1.7% post term. The means of BW, CHL, HC and CC were 2744.78 gm, 47.80 cm, 33.18 cm, and 30.20 cm with standard deviations of 528.29, 3.124, 1.78, and 2.35 respectively. These data vary as compared to the Kathmandu data, in case of birth weight for 10th and 90th centiles, and at 90th centile in case of length. Conclusions: This necessitates the update in the existing growth charts and develop in different geographical regions of a country.

Gestational Age Specific Postnatal Growth Curves for Singleton Babies in A Tertiary Hospital of Western Nepal

INTRODUCTION

Measurement of birth weight, crown-heel length, head circumference and chest circumference used to assess the intrauterine growth of a baby vary with altitude, race, gender, socioeconomic status, maternal size, and maternal diseases. The study aimed to construct centile charts for birth weight, crown-heel length and head circumference for new born at different gestational ages in Western Nepal.

METHODS

This was a descriptive cross-sectional study done over a period of 15 months in a tertiary care hospital of Western Nepal. Birth weight, length, head circumference and chest circumference were measured within 12-24 hours of birth. Gestational age was estimated from the first day of last menstrual period and New Ballard's scoring system. Microsoft 2007 Excel and SPSS-16 was used for data analysis. Cole's Lambda Mu Sigma method was used for constructing centile curves.

RESULTS

Out of 2000 babies analysed, 1910 samples were used to construct smoothed intrauterine growth curve of birth weight, crown-heel length, and head circumference from 33-42 weeks of gestation. Among all, 1147 (57.35%) were male and 853 (42.65%) were female, mean gestational age was 38.13±2.44 weeks. The means of birth weight, crown-heel length, head and chest circumference were 2744.78 gm, 47.80 cm, 33.18 cm, and 30.20 cm with standard deviations of 528.29, 3.124, 1.78, and 2.35 respectively.

CONCLUSIONS

This necessitates the update in the existing growth charts and development in different geographical regions of a country.

Patterns of domestic exposure to carbon monoxide and particulate matter in households using biomass fuel in Janakpur, Nepal

Household Air Pollution (HAP) from biomass cooking fuels is a major cause of morbidity and mortality in low-income settings worldwide. In Nepal the use of open stoves with solid biomass fuels is the primary method of domestic cooking. To assess patterns of domestic air pollution we performed continuous measurement of carbon monoxide (CO) and particulate Matter (PM2.5) in 12 biomass fuel households in Janakpur, Nepal. We measured kitchen PM2.5 and CO concentrations at one-minute intervals for an approximately 48-h period using the TSI DustTrak II 8530/SidePak AM510 (TSI Inc, St. Paul MN, USA) or EL-USB-CO data logger (Lascar Electronics, Erie PA, USA) respectively. We also obtained information regarding fuel, stove and kitchen characteristics and cooking activity patterns. Household cooking was performed in two daily sessions (median total duration 4 h) with diurnal variability in pollutant concentrations reflecting morning and evening cooking sessions and peak concentrations associated with fire-lighting. We observed a strong linear relationship between PM2.5 measurements obtained by co-located photometric and gravimetric monitoring devices, providing local calibration factors of 4.9 (DustTrak) and 2.7 (SidePak). Overall 48-h average CO and PM2.5 concentrations were 5.4 (SD 4.3) ppm (12 households) and 417.6 (SD 686.4) μg/m3 (8 households), respectively, with higher average concentrations associated with cooking and heating activities. Overall average PM2.5 concentrations and peak 1-h CO concentrations exceeded WHO Indoor Air Quality Guidelines. Average hourly PM2.5 and CO concentrations were moderately correlated (r = 0.52), suggesting that CO has limited utility as a proxy measure for PM2.5 exposure assessment in this setting. Domestic indoor air quality levels associated with biomass fuel combustion in this region exceed WHO Indoor Air Quality standards and are in the hazardous range for human health.

Development of an occupational airborne chemical exposure matrix

BACKGROUND

Population-based studies of the occupational contribution to chronic obstructive pulmonary disease generally rely on self-reported exposures to vapours, gases, dusts and fumes (VGDF), which are susceptible to misclassification.

AIMS

To develop an airborne chemical job exposure matrix (ACE JEM) for use with the UK Standard Occupational Classification (SOC 2000) system.

METHODS

We developed the ACE JEM in stages: (i) agreement of definitions, (ii) a binary assignation of exposed/not exposed to VGDF, fibres or mists (VGDFFiM), for each of the individual 353 SOC codes and (iii) assignation of levels of exposure (L; low, medium and high) and (iv) the proportion of workers (P) likely to be exposed in each code. We then expanded the estimated exposures to include biological dusts, mineral dusts, metals, diesel fumes and asthmagens.

RESULTS

We assigned 186 (53%) of all SOC codes as exposed to at least one category of VGDFFiM, with 23% assigned as having medium or high exposure. We assigned over 68% of all codes as not being exposed to fibres, gases or mists. The most common exposure was to dusts (22% of codes with >50% exposed); 12% of codes were assigned exposure to fibres. We assigned higher percentages of the codes as exposed to diesel fumes (14%) compared with metals (8%).

CONCLUSIONS

We developed an expert-derived JEM, using a strict set of a priori defined rules. The ACE JEM could also be applied to studies to assess risks of diseases where the main route of occupational exposure is via inhalation.

Oxidative potential of smoke from burning wood and mixed biomass fuels

More than half the world's population still rely on burning biomass fuels to heat and light their homes and cook food. Household air pollution, a common component of which is inhalable particulate matter (PM), emitted from biomass burning is associated with increased vulnerability to respiratory infection and an enhanced risk of developing chronic obstructive pulmonary disease. In the light of an emerging hypothesis linking chronic PM exposure during childhood and increased vulnerability to respiratory diseases in adulthood, in a chain of events involving oxidative stress, reduced immunity and subsequent infection, the aim of this study was to characterise the oxidative potential (OP) of PM collected during the burning of wood and mixed biomass, whilst cooking food in the Kathmandu Valley, Nepal. Our assessments were based on the capacity of the particles to deplete the physiologically relevant antioxidants from a validated, synthetic respiratory tract lining fluid (RTLF). Incubation of mixed biomass and wood smoke particles suspensions with the synthetic RTLF for 4 h resulted in a mean loss of ascorbate of 64.76 ± 16.83% and 83.37 ± 14.12% at 50 μg/ml, respectively. Reduced glutathione was depleted by 49.29 ± 15.22% in mixed biomass and 65.33 ± 13.01% in wood smoke particles under the same conditions. Co-incubation with the transition metal chelator diethylenetriaminepentaacetate did not inhibit the rate of ascorbate oxidation, indicating a negligible contribution by redox-active metals in these samples. The capacity of biomass smoke particles to elicit oxidative stress certainly has the potential to contribute towards negative health impacts associated with traditional domestic fuels in the developing world.

Biomass fuel use and the exposure of children to particulate air pollution in southern Nepal

The exposure of children to air pollution in low resource settings is believed to be high because of the common use of biomass fuels for cooking. We used microenvironment sampling to estimate the respirable fraction of air pollution (particles with median diameter less than 4 μm) to which 7-9 year old children in southern Nepal were exposed. Sampling was conducted for a total 2649 h in 55 households, 8 schools and 8 outdoor locations of rural Dhanusha. We conducted gravimetric and photometric sampling in a subsample of the children in our study in the locations in which they usually resided (bedroom/living room, kitchen, veranda, in school and outdoors), repeated three times over one year. Using time activity information, a 24-hour time weighted average was modeled for all the children in the study. Approximately two-thirds of homes used biomass fuels, with the remainder mostly using gas. The exposure of children to air pollution was very high. The 24-hour time weighted average over the whole year was 168 μg/m(3). The non-kitchen related samples tended to show approximately double the concentration in winter than spring/autumn, and four times that of the monsoon season. There was no difference between the exposure of boys and girls. Air pollution in rural households was much higher than the World Health Organization and the National Ambient Air Quality Standards for Nepal recommendations for particulate exposure.

Lung cancer risk and solid fuel smoke exposure: a systematic review and meta-analysis

The aim of this systematic review was to quantify the impact of biomass fuel and coal use on lung cancer and to explore reasons for heterogeneity in the reported effect sizes. A systematic review of primary studies reporting the relationship between solid fuel use and lung cancer was carried out, based on pre-defined criteria. Studies that dealt with confounding factors were used in the meta-analysis. Fuel types, smoking, country, cancer cell type and sex were considered in sub-group analyses. Publication bias and heterogeneity were estimated. The pooled effect estimate for coal smoke as a lung carcinogen (OR 1.82, 95% CI 1.60-2.06) was greater than that from biomass smoke (OR 1.50, 95% CI 1.17-1.94). The risk of lung cancer from solid fuel use was greater in females (OR 1.81, 95% CI 1.54-2.12) compared to males (OR 1.16, 95% CI 0.79-1.69). The pooled effect estimates were 2.33 (95% CI 1.72-3.17) for adenocarcinoma, 3.58 (1.58-8.12) for squamous cell carcinoma and 1.57 (1.38-1.80) for tumours of unspecified cell type. These findings suggest that in-home burning of both coal and biomass is consistently associated with an increased risk of lung cancer.

The non-occupational environment and the lung: opportunities for intervention

Many environmental factors, both indoors and outdoors, can cause or worsen respiratory disease. Although in many cases individuals have little influence over environmental exposures (e.g., weather conditions), there are many (such as environmental tobacco smoke (ETS) and outdoor air pollution) where interventions can improve health. While for environmental exposures such as air pollution, remediation largely devolves to the government, for exposures such as ETS advice to individuals in these settings will confer benefit. Climate change has begun to feature more and more in the context of health but how this may affect pulmonary disease remains debatable. It is possible that heat associated changes in allergen exposures may be more than counterbalanced by potential reductions in cold related exacerbations of diseases such as COPD. An improved assessment of environmental exposures is key in how we approach the effects of the environment on lung disease which would allow better understanding of gene-environment interactions and how remediation might influence population health for the better.