Impact of micronutrients on respiratory infections

The Impact of Malnutrition on the Developing Lung and Long-Term Lung Health: A Narrative Review of Global Literature

Worldwide, over 2 billion children under the age of 5 experience stunting, wasting, or are underweight. Malnutrition contributes to 45% of all deaths in this age group (approximately 3.1 million deaths) [1]. Poverty, food insecurity, suboptimal feeding practices, climate change, and conflict are all contributing factors. Malnutrition causes significant respiratory problems, including increased risk of respiratory infections, impaired lung function, and increased risk of subsequent adult respiratory disease, including asthma, COPD, and lung cancer. Childhood malnutrition not only has serious consequences for children's health but it also has numerous consequences on wellbeing and educational attainment. Childhood malnutrition is a complex and multifaceted problem. However, by understanding and addressing the underlying causes, and investing in prevention and treatment programs, it is possible to maximize children's health and wellbeing on a global scale. This narrative review will focus on the impact of childhood malnutrition on lung development, the consequent respiratory disease, and what actions can be taken to reduce the burden of malnutrition on lung health.

The effect of undernutrition on sputum culture conversion and treatment outcomes among people with multidrug-resistant tuberculosis: a systematic review and meta-analysis

OBJECTIVES

We aimed to evaluate the effect of undernutrition on sputum culture conversion and treatment outcomes among people with multidrug-resistant tuberculosis (MDR-TB).

METHODS

We searched for publications in the Medline, Embase, Scopus, and Web of Science databases. We conducted a random-effect meta-analysis to estimate the effects of undernutrition on sputum culture conversion and treatment outcomes. Hazard ratio (HR) for sputum culture conversion and odds ratio (OR) for end-of-treatment outcomes, with 95% CI, were used to summarize the effect estimates. Potential publication bias was checked using funnel plots and Egger's tests.

RESULTS

Of the 2358 records screened, 63 studies comprising a total of 31,583 people with MDR-TB were included. Undernutrition was significantly associated with a longer time to sputum culture conversion (HR 0.7, 95% CI 0.6-0.9, I² = 67·1%), and a higher rate of mortality (OR 2.8, 95% CI 2.1-3.6, I² = 21%) and unsuccessful treatment outcomes (OR 1.8, 95% CI 1.5-2.1, I² = 70%). There was no significant publication bias in the included studies.

CONCLUSION

Undernutrition was significantly associated with unsuccessful treatment outcomes, including mortality and longer time to sputum culture conversion among people with MDR-TB. These findings have implications for supporting targeted nutritional interventions alongside standardized TB drugs.

Vitamin D3 in acute respiratory infections in patients under five years old (Cartagena de Indias, Colombia)

Background and Aim. Low serum levels of 25-hydroxyvitamin D3 are associated with an increased risk of Acute Respiratory Infection (ARI) that is among the most important causes of morbidity and mortality in children under 5 years old. We describe the clinical behavior of acute respiratory infections in patients under five years ago in one sanitary institution in Colombia after VD3 supplementation. Material and Methods. A case series was conducted on 38 patients of both genders aged less to 5 years ago was included. Participants were supplied 50,000 units of VD3 orally each month for three months. The number of events, consultations for emergency services, and hospitalization due to acute respiratory infections (ARIs) before and after VD3 administration were described. Results. The average age of the participants was 25.81 ± 17.50 months. The average clinical ARIs per month was 4.02 (95% CI 3.64-4.40) before VD3 administration. Fewer episodes at the end of the three cycles was found at 2.23/month (95% CI 1.81-2.65; p=0.0230). The average consultations for emergency services during the three months before VD3 administration was 2.15 (95% CI 1.77-2.53). After three months of treatment, the average use of emergency services decreased to 0.52 (95% CI 0.37-0.72; p=0.0180). After the administration of the three doses of VD3, only one patient required hospitalization (2.63%; : 0.026 (IC95% 0.02-0.03; p=0.0368)). Conclusions. The administration of vitamin D3 could have a benefit in decreasing the number of episodes, emergencies, and hospitalization for ARI in children under five years old. Trial studies are required to determine this potential benefit.

Prognostic Role of Malnutrition Diagnosed by Bioelectrical Impedance Vector Analysis in Older Adults Hospitalized with COVID-19 Pneumonia: A Prospective Study

Background: Little is known on the clinical relevance of the nutritional status and body composition of patients hospitalized with SARS-CoV-2 infection. The aim of our study was to assess the prevalence of malnutrition in patients with COVID-19 pneumonia using bioelectrical impedance vector analysis (BIVA), and to evaluate the relationship of their nutritional status with the severity and outcome of disease. Methods: Among 150 consecutive patients who were hospitalized with COVID-19 pneumonia, 37 (24.3%) were classified as malnourished by BIVA, and were followed-up for 60 days from admission. Outcome measures were differences in the need for invasive mechanical ventilation, in-hospital mortality, and the duration of hospital stay in survivors. Results: During 60 days of follow-up, 10 (27%) malnourished patients and 13 (12%) non-malnourished patients required invasive mechanical ventilation (p = 0.023), and 13 (35%) malnourished patients and 9 (8%) non-malnourished patients died (p < 0.001). The average duration of the hospital stay in survivors was longer in patients with malnutrition (18.2 ± 15.7 vs. 13.2 ± 14.8 days, p < 0.001). In survival analyses, mechanical ventilation free (log-rank 7.887, p = 0.050) and overall (log-rank 17.886, p < 0.001) survival were significantly longer in non-malnourished than malnourished patients. The Cox proportional ratio showed that malnutrition was associated with an increased risk of mechanical ventilation (HR 4.375, p = 0.004) and death (HR 4.478, p = 0.004) after adjusting for major confounders such as age, sex, and BMI. Conclusions: Malnutrition diagnosed with BIVA was associated with worse outcomes in hospitalized patients with COVID-19 pneumonia.

Vitamin D deficiency as the risk of respiratory tract infections in the institutionalized elderly: A prospective 1-year cohort study

BACKGROUND & AIMS

Respiratory tract infections (RTIs) are one of the major causes of morbidity and mortality in the elderly. Since vitamin D is known to play important roles in immunity, and its deficiency has been reported to be prevalent in the elderly, we have studied the relationship between serum 25-hydroxyvitamin D [25(OH)D] level, which is the most reliable marker for vitamin D status, and the incidence of RTIs in the institutionalized elderly by a prospective observational study.

METHODS

From 208 Japanese subjects aged 60 and older fulfilling the inclusion criteria, 148 subjects remained after propensity score matching. Data were obtained from the medical records including their age, gender, histories of co-morbidities and medications, the incidence of acute RTIs including pneumonia. Measurement of serum 25(OH)D level and assessment of nutrients intake including vitamin D were done at baseline. Cox's proportional hazard analysis was performed to assess the significant predictors for RTIs during the follow-up period.

RESULTS

The median observation duration was 354.2 days, and the incidence of RTIs was 75.8 person-years. Subjects with RTIs had significantly lower serum 25(OH)D concentration, and a higher prevalence of vitamin D deficiency (25(OH)D < 10 ng/mL). Cox's proportional hazard analysis revealed that vitamin D deficiency was a significant predictor for RTIs.

CONCLUSIONS

Our results suggested that vitamin D deficiency was a significant predictor for an increased incidence of RTIs in institutionalized elderly, and the necessity of vitamin D supplementation for the prevention of RTIs was considered.

Food and COVID-19: Preventive/Co-therapeutic Strategies Explored by Current Clinical Trials and in Silico Studies

Foods, food ingredients, and their balanced consumption are recognized to have an important role in achieving or maintaining a state of wellbeing by acting as carriers of functional components and bioactive molecules. However, the potential contribution of foods to consumers' health has so far only been partially exploited. The rapidly evolving scenario of the coronavirus disease 2019 (COVID-19) pandemic is stimulating profound reflection on the relationships between food and the etiological agent, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, the status of knowledge regarding food as a possible defense/co-therapeutic strategy against the SARS-CoV-2 coronavirus is considered through the discussion of two main current lines of research. One line of research relates to the role of micronutrients, food components, and diets in the strengthening of the immune system through clinical trials; formulations could be developed as immune system enhancers or as co-adjuvants in therapies. The other line of research relates to investigation of the chemical interactions that specific food compounds can have with host or virus targets so as to interfere with the viral infective cycle of SARS-CoV-2. This line requires, as a first step, an in silico evaluation to discover lead compounds, which may be further developed through drug-design studies, in vitro and in vivo tests, and, finally, clinical trials to obtain therapeutic molecules. All of these promising strategies promote the role of food in preventive/co-therapeutic strategies to tackle the COVID-19 pandemic.

Adjunctive vitamin A and D during pulmonary tuberculosis treatment: a randomized controlled trial with a 2 × 2 factorial design

BACKGROUND AND OBJECTIVE

Vitamin A and D have immunoregulatory effects and may improve the response to pulmonary tuberculosis treatment. The interaction of vitamin A and D on pulmonary tuberculosis treatment has not been studied. The objective is to investigate the effects of adjunctive supplementation of vitamin A, D and their interaction on the outcome of pulmonary tuberculosis treatment, primarily time to sputum smear conversion.

METHODS

We conducted a randomized controlled trial with a 2 × 2 factorial design in Qingdao, China. Eight hundred patients were enrolled to receive standard pulmonary tuberculosis therapy alone (control), or together with vitamin A (2000 IU d^-1), or vitamin D (400 IU d^-1) or a combination of vitamin A (2000 IU d^-1) and D (400 IU d^-1) during the intensive-phase of pulmonary tuberculosis treatment.

RESULTS

761 patients were included in the tuberculosis symptom analysis; 521 patients with positive baseline sputum smear results were included in the sputum smear analysis. The allocation to vitamin A or D did not significantly influence the time to sputum smear conversion [vitamin A: adjusted hazard ratio: 1.021, 95% CI: (0.821, 1.271); vitamin D: adjusted hazard ratio: 0.949, 95% CI: (0.760, 1.185)]. No significant interaction was observed between vitamin A and D supplementation (p = 0.660). Vitamin D supplementation significantly relieved the tuberculosis symptoms as indicated by decreased TBscore [mean difference: -0.2, 95% CI: (-0.4, 0)] in week 2 to 4.

CONCLUSIONS

Adjunctive supplementation of vitamin A and/or D did not improve the time to smear conversion in pulmonary tuberculosis patients. However vitamin D supplementation significantly improved tuberculosis symptoms during the first month of pulmonary tuberculosis treatment.

Undernutrition and Tuberculosis: Public Health Implications

Almost 800 million people are chronically undernourished worldwide, of whom 98% are in low- and middle-income countries where tuberculosis is endemic. In many tuberculosis-endemic countries, undernutrition is a driver of tuberculosis incidence and associated with a high population attributable fraction of tuberculosis and poor treatment outcomes. Data suggest that undernutrition impairs innate and adaptive immune responses needed to control Mycobacterium tuberculosis infection and may affect responses to live vaccines, such as BCG. Given its impact on tuberculosis, addressing undernutrition will be a vital component of the World Health Organization End TB strategy. This narrative review describes the effect of undernutrition on the immune response, vaccine response, and tuberculosis incidence, severity, and treatment outcomes.

Influence of vitamin D deficiency on T cell subsets and related indices during spinal tuberculosis

The present study investigated the effects of vitamin D deficiency on T cell subsets in patients with spinal tuberculosis. In addition, the influence of vitamin D deficiency was investigated on the expression of cytokines IL-1β, IL-6 and TNF-α in intervertebral disc lesions of patients. One hundred and seventeen patients with spinal tuberculosis who received operative treatment in the Department of Orthopedics in Wuhan City Third Hospital from March 2012 to March 2015 were collected. The patients were divided depending upon vitamin D content into the control group (64 cases, vitamin D content <25 nmol/l) and experimental group (53 cases, vitamin D content >50 nmol/l). Immunofluorescence method was applied to determine the content of T cell subsets in both groups of patients. Intervertebral disc lesion tissues of two groups of patients were obtained during surgery then treated with HE staining and immunohistochemical staining. The values of average optical density obtained under light microscope were observed as the expression quantities of IL-1β, IL-6 and TNF-α, to explore the relationship between vitamin D and the expression of cytokines. When vitamin D is lacking, the expression of T lymphocyte subsets in patients with spinal tuberculosis significantly decreased. Compared with experimental group, the difference was statistically significant (P<0.05). Further, the expression of cytokines IL-1β, IL-6 and TNF-α in intervertebral disc lesion tissues of patients with spinal tuberculosis were significantly higher than those of patients with spinal tuberculosis whose vitamin D content was normal (P<0.05). In the control group, vitamin D content was negatively correlated with the expression of IL-1β, IL-6 and TNF-α. The expression of T lymphocyte subsets in patients with vitamin D deficiency was significantly reduced, and the immune function decreased. The expression of IL-1β, IL-6 and TNF-α in lesions were significantly higher than those of patients with normal vitamin D content. In addition, the lower the content of vitamin D was, the more active the expression of inflammatory factors were, which was not conducive to the recovery of tuberculosis lesions.

Nutritional status, exclusive breastfeeding and management of acute respiratory illness and diarrhea in the first 6 months of life in infants from two regions of Indonesia

BACKGROUND

Infant morbidity and mortality rates remain high in Indonesia, with acute respiratory illnesses (ARI) and diarrhea the leading two health problems in children under 5 years. We aimed to describe the nutritional status, feeding practice and case management of ARI and diarrhea of infants from two regions of Indonesia during the first 6 months of life.

METHODS

This study was an observational study conducted in parallel to an immunogenicity and efficacy trial of an oral rotavirus vaccine (RV3-BB) in the Klaten and Yogyakarta regions, Indonesia. Mothers were interviewed at 3 time points: within the first 6 days of their infant's life, and at 8-10 and 22-24 weeks of age. Questions asked included pregnancy history, infant nutritional status, feeding status and health of infants within up to 2 weeks prior to the assessment.

RESULTS

Between February 2013 and January 2014, 233 mother-infant pairs were recruited. 60% (136/223) of infants were exclusively breastfed (EBF) until 6 months of age with the strongest support for EBF reported by mothers themselves 70% (101/223) and 25% (36/223) from their partners. At 6 months, 6% (14/223) of infants were underweight and severely underweight; 4% (8/ 223) wasted and severely wasted; and 12% (28/223) were stunted and severely stunted. Non-recommended medication use was high, with 54% (21/39) of infants with reported cough within 2 weeks of an assessment receiving cough medication, 70% (27 /39) an antihistamine, 26% (10/39) a mucolytic and 15% (6 /39) an oral bronchodilator. At age 22-24 week, infants with reported diarrhea within 2 weeks of an assessment had low use of oral rehydration solutions (ORS) (3/21;14%) and zinc therapy (2/ 21;10%).

CONCLUSION

In this unique observational study, breastfeeding rates of 60% at 6 months were below the Indonesian national target of >75%. Adherence to WHO guidelines for management of ARI and diarrhea was poor, with high use of non-recommended cough medications and oral bronchodilators in the first 6 months of life and low use of ORS and zinc therapy. Ongoing education of primary health care workers and parents regarding management of common illness is needed in Indonesia.

Vit D deficiency is a possible risk factor in ARS

Vitamin D deficiency is effective in the development of acute rhinosinusitis and prolongation of inflammation by increasing inflammation in the sinonasal epithelium. Vitamin D deficiency is important in the development of bone barriers that prevent the complication of acute rhinosinusitis. Although Vitamin D levels may be a variable risk factor for various respiratory tract disorders, there are limited data on the role in sinonasal infections. Our aim was to investigate the association of 25-hydroxy-vitamin D (25OHD) levels with acute rhinosinusitis (ARS) and preseptal cellulitis complications. The type of the study is prospective case-control study. Fifteen patients in the pediatric age group with ARS-induced preseptal cellulitis complication were identified as Group 1, fifteen patients with ARS and without complication were identified as Group 2, and fifteen healthy volunteers were identified as Group 3. Serum 25OHD levels (nmol/l) were measured in addition to routine blood tests at the first admission of patients participating in the study. Statistical analysis was performed between groups. The ages of the cases ranged from 1 to 14 years with a mean of 5.62 ± 3.42 years. 55.6% of the cases (n = 25) were male; 44.4% (n = 20) were female children. As a result of classification in which vitamin D levels were compared with normal values, there was a statistically significant difference according to the presence of ARS (Group-1 and Group 2) and absence of ARS (Group-3) (p < 0.05). A statistically significant difference was also found between Group 1 and Group-3 (p < 0.05). Statistically significant difference between Group 1 and Group 3 suggests that lack of vitamin D predisposes to the complication of preseptal cellulitis. Comparison of Group 1 and 2 with Group 3 (normal subjects) suggests that Vit D has a protective effect against developing sinusitis.

Association between serum vitamin D, retinol and zinc status, and acute respiratory infections in underweight and normal-weight children aged 6–24 months living in an urban slum in Bangladesh

We conducted a longitudinal assessment in 466 underweight and 446 normal-weight children aged 6–24 months living in the urban slum of Dhaka, Bangladesh to determine the association between vitamin D and other micronutrient status with upper respiratory tract infection (URI) and acute lower respiratory infection (ALRI). Incidence rate ratios of URI and ALRI were estimated using multivariable generalized estimating equations. Our results indicate that underweight children with insufficient and deficient vitamin D status were associated with 20% and 23–25% reduced risk of URI, respectively, compared to children with sufficient status. Underweight children, those with serum retinol deficiency were at 1·8 [95% confidence interval (CI) 1·4–2·4] times higher risk of ALRI than those with retinol sufficiency. In normal-weight children there were no significant differences between different vitamin D status and the incidence of URI and ALRI. However, normal-weight children with zinc insufficiency and those that were serum retinol deficient had 1·2 (95% CI 1·0–1·5) times higher risk of URI and 1·9 (95% CI 1·4–2·6) times higher risk of ALRI, respectively. Thus, our results should encourage efforts to increase the intake of retinol-enriched food or supplementation in this population. However, the mechanisms through which vitamin D exerts beneficial effects on the incidence of childhood respiratory tract infection still needs further research.

Association of Vitamin D Status and Acute Rhinosinusitis: Results From the United States National Health and Nutrition Examination Survey 2001-2006

Although vitamin D status may be a modifiable risk factor for various respiratory ailments, limited data exists regarding its role in sinonasal infections. Our goal was to investigate the association of 25-hydroxyvitamin D (25OHD) levels with acute rhinosinusitis (ARS) in a large, nationally representative sample of non-institutionalized individuals from the United States. In this cross-sectional study of individuals ≥ 17 years from the National Health and Nutrition Examination Survey 2001-2006, we used multivariable regression analysis to investigate the association of 25OHD levels with ARS, while adjusting for season, demographics (age, sex, race, and poverty-to-income ratio), and clinical data (smoking, asthma, chronic obstructive pulmonary disease, diabetes mellitus, and neutropenia). A total of 3921 individuals were included in our analyses. Median 25OHD level was 22 (interquartile range 16-28) ng/mL. Overall, 15.8% (95% confidence interval [CI] 14.4-17.7) of participants reported ARS within the 24 hours leading up to their survey participation. After adjusting for season, demographics, and clinical data, 25OHD levels were associated with ARS (odds ratio 0.88, 95% CI 0.78-0.99 per 10 ng/mL). When vitamin D status was dichotomized, 25OHD levels < 20 ng/mL were associated with 33% higher odds of ARS (odds ratio 1.33, 95% CI 1.03-1.72) compared with levels ≥ 20 ng/mL. Our analyses suggest that 25OHD levels are inversely associated with ARS. Randomized, controlled trials are warranted to determine the effect of optimizing vitamin D status on the risk of sinonasal infections.

Modeling historical tuberculosis epidemics among Canadian First Nations: effects of malnutrition and genetic variation

Late 19th century epidemics of tuberculosis (TB) in Western Canadian First Nations resulted in peak TB mortality rates more than six times the highest rates recorded in Europe. Using a mathematical modeling approach and historical TB mortality time series, we investigate potential causes of high TB mortality and rapid epidemic decline in First Nations from 1885 to 1940. We explore two potential causes of dramatic epidemic dynamics observed in this setting: first, we explore effects of famine prior to 1900 on both TB and population dynamics. Malnutrition is recognized as an individual-level risk factor for TB progression and mortality; its population-level effects on TB epidemics have not been explored previously. Second, we explore effects of heterogeneity in susceptibility to TB in two ways: modeling heterogeneity in susceptibility to infection, and heterogeneity in risk of developing disease once infected. Our results indicate that models lacking famine-related changes in TB parameters or heterogeneity result in an implausibly poor fit to both the TB mortality time series and census data; the inclusion of these features allows for the characteristic decline and rise in population observed in First Nations during this time period and confers improved fits to TB mortality data.

Role of nutrition in performance enhancement and postexercise recovery

A number of factors contribute to success in sport, and diet is a key component. An athlete's dietary requirements depend on several aspects, including the sport, the athlete's goals, the environment, and practical issues. The importance of individualized dietary advice has been increasingly recognized, including day-to-day dietary advice and specific advice before, during, and after training and/or competition. Athletes use a range of dietary strategies to improve performance, with maximizing glycogen stores a key strategy for many. Carbohydrate intake during exercise maintains high levels of carbohydrate oxidation, prevents hypoglycemia, and has a positive effect on the central nervous system. Recent research has focused on athletes training with low carbohydrate availability to enhance metabolic adaptations, but whether this leads to an improvement in performance is unclear. The benefits of protein intake throughout the day following exercise are now well recognized. Athletes should aim to maintain adequate levels of hydration, and they should minimize fluid losses during exercise to no more than 2% of their body weight. Supplement use is widespread in athletes, with recent interest in the beneficial effects of nitrate, beta-alanine, and vitamin D on performance. However, an unregulated supplement industry and inadvertent contamination of supplements with banned substances increases the risk of a positive doping result. Although the availability of nutrition information for athletes varies, athletes will benefit from the advice of a registered dietician or nutritionist.

Vitamin D status and acute respiratory infection: cross sectional results from the United States National Health and Nutrition Examination Survey, 2001-2006

Vitamin D is a promising, though under-explored, potential modifiable risk factor for acute respiratory infections (ARIs). We sought to investigate the association of vitamin D status with ARI in a large, nationally-representative sample of non-institutionalized individuals from the United States. We analyzed 14,108 individuals over 16 years of age in the National Health and Nutrition Survey (NHANES) 2001-2006 in this cross-sectional study. We used locally weighted scatterplot smoothing (LOWESS) to depict the relationship between increasing 25-hydroxyvitamin D (25OHD) levels and ARI. We then performed a multivariable regression analysis to investigate the association of 25OHD levels with ARI, while adjusting for known confounders. The median serum 25OHD level was 21 (IQR 15-27) ng/mL. Overall, 4.8% (95% CI: 4.5-5.2) of participants reported an ARI within 30 days before their participation in the national survey. LOWESS analysis revealed a near-linear relationship between vitamin D status and the cumulative frequency of ARI up to 25OHD levels around 30 ng/mL. After adjusting for season, demographic factors, and clinical data, 25OHD levels <30 ng/mL were associated with 58% higher odds of ARI (OR 1.58; 95% CI: 1.07-2.33) compared to levels ≥30 ng/mL. Among the 14,108 participants in NHANES 2001-2006, 25OHD levels were inversely associated with ARI. Carefully designed, randomized, controlled trials are warranted to determine the effect of optimizing vitamin D status on the risk of ARI.

Effect of micronutrient supplementation on treatment outcomes in children with intrathoracic tuberculosis: a randomized controlled trial

BACKGROUND

Micronutrients play an important role in immune function. To our knowledge, there have been no comprehensive studies on the role of micronutrient supplementation in children with tuberculosis.

OBJECTIVE

We assessed the effect of micronutrient supplementation in children treated with antituberculosis therapy (ATT).

DESIGN

A randomized, double-blind, placebo-controlled trial that used a 2 × 2 factorial design was undertaken at 2 teaching hospitals in Delhi. Children with newly diagnosed intrathoracic tuberculosis were enrolled, and they received ATT together with daily supplementation for 6 mo with either zinc alone, micronutrients without zinc, micronutrients in combination with zinc, or a placebo. Main outcomes were weight gain and an improvement in a chest X-ray (CXR) lesion assessed at 6 mo of treatment.

RESULTS

A total of 403 children were enrolled and randomly assigned. A microbiological diagnosis of tuberculosis was confirmed in 179 children (44.4%). The median (95% CI) increase in weight-for-age z score at 6 mo was not significantly different between subjects who received micronutrients [0.75 (0.66, 0.84)] and those who did not receive micronutrients [0.76 (0.67, 0.85)] and between subjects who received zinc [0.76 (0.68, 0.85)] and those who did not receive zinc [0.75 (0.66, 0.83)]. An improvement in CXR was observed in 285 children, but there was no difference between those receiving zinc and no zinc or between those receiving micronutrients and no micronutrients after 6 mo of ATT. However, children who received micronutrients had a faster gain in height over 6 mo than did those who did not receive micronutrients (height-for-age z score Δ = 0.08; P = 0.014).

CONCLUSIONS

Micronutrient supplementation did not modify the weight gain or clearance of lesions on CXR in children with intrathoracic tuberculosis. However, micronutrient supplementation during treatment may improve height gain in children with intrathoracic tuberculosis. This trial was registered at clinicaltrials.gov as NCT00801606.

Respiratory risks from household air pollution in low and middle income countries

A third of the world's population uses solid fuel derived from plant material (biomass) or coal for cooking, heating, or lighting. These fuels are smoky, often used in an open fire or simple stove with incomplete combustion, and result in a large amount of household air pollution when smoke is poorly vented. Air pollution is the biggest environmental cause of death worldwide, with household air pollution accounting for about 3·5-4 million deaths every year. Women and children living in severe poverty have the greatest exposures to household air pollution. In this Commission, we review evidence for the association between household air pollution and respiratory infections, respiratory tract cancers, and chronic lung diseases. Respiratory infections (comprising both upper and lower respiratory tract infections with viruses, bacteria, and mycobacteria) have all been associated with exposure to household air pollution. Respiratory tract cancers, including both nasopharyngeal cancer and lung cancer, are strongly associated with pollution from coal burning and further data are needed about other solid fuels. Chronic lung diseases, including chronic obstructive pulmonary disease and bronchiectasis in women, are associated with solid fuel use for cooking, and the damaging effects of exposure to household air pollution in early life on lung development are yet to be fully described. We also review appropriate ways to measure exposure to household air pollution, as well as study design issues and potential effective interventions to prevent these disease burdens. Measurement of household air pollution needs individual, rather than fixed in place, monitoring because exposure varies by age, gender, location, and household role. Women and children are particularly susceptible to the toxic effects of pollution and are exposed to the highest concentrations. Interventions should target these high-risk groups and be of sufficient quality to make the air clean. To make clean energy available to all people is the long-term goal, with an intermediate solution being to make available energy that is clean enough to have a health impact.

Short- and long-term efficacy of prednisolone for first acute rhinovirus-induced wheezing episode

Background

Rhinovirus-induced wheezing is an important risk factor for recurrent wheezing. There are no randomized controlled trials on the effect of systemic corticosteroids in patients with this disease.

Objective

We sought to study the short- and long-term effects of prednisolone treatment of the first acute, moderate-to-severe, rhinovirus-induced wheezing episode in young children.

Methods

After confirming rhinovirus from nasopharyngeal aspirate by using PCR, 79 children with a first wheezing episode at age 3 to 23 months were randomized to receive oral prednisolone (first dose of 2 mg/kg, followed by 2 mg/kg/d in 2 divided doses for 3 days) or placebo. The trial was double blind throughout the 12-month follow-up. The primary outcomes were long term: new physician-confirmed wheezing episode within 2 months, number of physician-confirmed wheezing episodes within 12 months, and initiation of regular controller medication for asthma symptoms within 12 months. The primary interaction analysis examined rhinovirus load.

Results

Seventy-four patients completed the study (mean age, 13 months; 28% atopic). Long-term outcomes did not differ between groups (all P ≥ .30). For short-term outcomes, the prednisolone group had less cough, rhinitis, noisy breathing, severe breathing difficulties, and nocturnal respiratory symptoms at home within 2 weeks (all P < .05). The 25 children with greater than 7000 rhinovirus copies/mL (most sensitive cutoff) benefitted from prednisolone in terms of less risk of physician-confirmed recurrence within 2 and 12 months compared with placebo (both P < .05).

Conclusions

Prednisolone cannot be routinely recommended for all young children experiencing their first acute, moderate-to-severe, rhinovirus-induced wheezing episode. Prednisolone might be beneficial in a subgroup of children with high viral loads.

Risk factors and outcomes for pandemic H1N1 influenza compared with seasonal influenza in hospitalized children in China

OBJECTIVE

To compare clinical features and outcomes of children hospitalized in China with pandemic (p)H1N1 between 2009 and 2010 versus seasonal influenza A between 2008 and 2009.

METHODS

Systematic review of laboratory-confirmed admissions to the Children's Hospital, Soochow University (Suzhou, China).

RESULTS

Seventy-five children younger than 14 years of age were admitted with pH1N1, 70 with H3N2 and three with seasonal H1N1. With pH1N1, the mean age was older (36 months versus seven months), the length of stay was longer (nine days versus seven days), underlying conditions were more common (29% versus 15%), anemia was more common (11% versus 0%) (P<0.05), with trends toward more secondary bacterial pneumonia and intensive care unit care, compared with seasonal influenza. Two of the 75 children with pH1N1 died versus no deaths in children with seasonal influenza. None of the children had received pH1N1, seasonal influenza, conjugated pneumococal or Haemophilus influenzae b vaccines.

CONCLUSION

In China, children hospitalized with pH1N1 influenza differed from case series in Canada, Argentina and the United States, suggesting that locale, background and health care system influenced the presentation and outcomes of pandemic and seasonal influenza.

Low serum 25-hydroxyvitamin D level: an independent risk factor for tuberculosis?

BACKGROUND & AIMS

Vitamin D deficiency has been associated with an increased risk of tuberculosis (TB). Low serum vitamin D levels may also be associated with poor nutritional status in TB patients. Therefore, this study aimed at evaluating the association between low serum vitamin D level and TB, regardless of other nutritional factors.

METHODS

Baseline serum 25-hydroxyvitamin D (25(OH)D3) levels in TB patients were measured before treatment and 1 year after treatment onset using liquid chromatography-tandem mass spectrometry, and were compared with 25(OH)D3 levels in controls. Nutritional parameters were also measured in all subjects.

RESULTS

In total, 165 active pulmonary TB patients and 197 controls were included in the study. Significantly higher prevalence of 25(OH)D3 insufficiency (<20 ng/mL) and deficiency (<10 ng/mL) in TB patients was showed compared to controls. Serum 25(OH)D3 levels and nutritional parameters were significantly lower in untreated TB patients than in controls. One year after TB treatment onset, nutritional parameters significantly increased; however, serum 25(OH)D3 levels in TB patients showed no significant improvement compared to baseline.

CONCLUSIONS

These results suggest that a low serum 25(OH)D3 level might be a risk factor for TB, independent of nutritional status.

The association between vitamin D status and recurrent wheezing

OBJECTIVE

To investigate association between vitamin D status and recurrent wheezing in infants.

METHODS

Thirty infants with recurrent wheezing and 45 healthy, similar aged infants without any history of acute or chronic illness were included in the study. The clinical features of infants were recorded and serum 25-hydroxyvitamin D [25(OH)D] levels were measured. Data analysis was performed using SPSS 13 package program.

RESULTS

The mean value of 25 (OH) D vitamin levels were 22.1 ± 8.9 IU/L and 18.8 ± 11 IU/L for the control and recurrent attack group respectively. Seventy-three percent of subjects with recurrent wheezing had vitamin D levels in the deficient range (<20 ng/ml) and 48.9 % had vitamin D levels under < 20 ng/ml in the control group. The percentage of insufficient vitamin D levels (<30 ng/ml) were 90 and 77.8 for the patient and control group respectively. Eight patients had extremely deficient vitamin D (<10 ng/ml) levels. There was no statistical significance between the groups in terms of the distribution of 25 (OH)D level.

CONCLUSIONS

The present study did not demonstrate significant association between vitamin D status and recurrent wheezing in the infants.

Serum 25-hydroxyvitamin D concentrations and waning pneumococcal antibody titers among individuals with atopy

Serum 25-hydroxyvitamin D (25[OH]D) concentrations are positively associated with pneumococcal antibody titers (PATs) in subjects with atopy or asthma. Little is known about the association of serum 25(OH)D concentrations and the waning of PATs over time in subjects with or without atopy. This study was designed to determine whether serum 25(OH)D concentrations are associated with waning of PATs and if such relationship is modified by atopic conditions. The study was designed as a prospective cohort study, which followed 20 asthmatic patients and 19 individuals without asthma for an average of 12 months. We measured PATs and serum 25(OH)D concentrations at baseline and at a subsequent follow-up visit. Asthma was ascertained by predetermined criteria. The association between serum 25(OH)D concentrations and PATs was determined by Pearson's correlation coefficient and a least square model. Of the 39 children and adults, 21(53%) were male subjects, all were white, and 6 (15%) were children. There was an overall negative correlation between serum 25(OH)D concentrations and the decrease of PATs during follow-up (r = -0.47; p = 0.004), suggesting that higher 25(OH)D concentrations were associated with a reduction in waning of PATs over time. Controlling for follow-up duration and pneumococcal colonization, these trends were significant among asthmatic patients but not in individuals without asthma. Similar trends were observed for individuals with or without other atopic conditions. Serum 25(OH)D concentrations are inversely associated with the waning of PATs over time, especially individuals with asthma and other atopy conditions. These study findings deserve further investigation.

Nutrition and asthma

Over the past four decades, the prevalence of asthma has markedly increased in Westernized countries and countries transitioning to this lifestyle. It has been hypothesized that these increases are a consequence of changing environmental and/or behavioral factors. The modification of dietary habits (ie, decreased intake of fruits/vegetables and increased intake of "Westernized" processed foods) and a decrease in sun exposure have led to decreased intake of antioxidant vitamins and fatty acids and to decreased circulating levels of vitamin D, and have been proposed to explain the rise in asthma prevalence. This article summarizes the main findings on foods and nutrients connected to asthma based on several exhaustive recent reviews on the topic, and examines the evidence for an effect of dietary patterns on asthma. Overall, findings underscore the importance of conducting prospective studies and clinical trials to better understand the role of diet in the etiology of asthma.

Vitamin D: effects on childhood health and disease

Vitamin D is a key nutrient for both healthy children and those with chronic illnesses. Understanding its roles in health and disease has become one of the most important issues in the nutritional management of children. Formal guidelines related to nutrient requirements for vitamin D in healthy children, recommending dietary intakes of 400 IU per day for infants and 600 IU per day for children over 1 year of age, were released by the Institute of Medicine in November 2010. However, application of these guidelines to children with acute and chronic illnesses is less clear. In this Review, we consider major illness categories and specific examples of conditions in children that might be affected by vitamin D. This information can be used in developing both model systems of investigation and clinical trials of vitamin D in children with acute and chronic illnesses.

Randomized trial of vitamin D supplementation and risk of acute respiratory infection in Mongolia

OBJECTIVE

Observational studies suggest that serum levels of 25-hydroxyvitamin D (25[OH]D) are inversely associated with acute respiratory infections (ARIs). We hypothesized that vitamin D supplementation of children with vitamin D deficiency would lower the risk of ARIs.

METHODS

By using cluster randomization, classrooms of 744 Mongolian schoolchildren were randomly assigned to different treatments in winter (January-March). This analysis focused on a subset of 247 children who were assigned to daily ingestion of unfortified regular milk (control; n = 104) or milk fortified with 300 IU of vitamin D(3) (n = 143). This comparison was double-blinded. The primary outcome was the number of parent-reported ARIs over the past 3 months.

RESULTS

At baseline, the median serum 25(OH)D level was 7 ng/mL (interquartile range: 5-10 ng/mL). At the end of the trial, follow-up was 99% (n = 244), and the median 25(OH)D levels of children in the control versus vitamin D groups was significantly different (7 vs 19 ng/mL; P < .001). Compared with controls, children receiving vitamin D reported significantly fewer ARIs during the study period (mean: 0.80 vs 0.45; P = .047), with a rate ratio of 0.52 (95% confidence interval: 0.31-0.89). Adjusting for age, gender, and history of wheezing, vitamin D continued to halve the risk of ARI (rate ratio: 0.50 [95% confidence interval: 0.28-0.88]). Similar results were found among children either below or above the median 25(OH)D level at baseline (rate ratio: 0.41 vs 0.57; P(interaction) = .27).

CONCLUSIONS

Vitamin D supplementation significantly reduced the risk of ARIs in winter among Mongolian children with vitamin D deficiency.

Vitamin D in early childhood and the effect on immunity to Mycobacterium tuberculosis

A potential role for vitamin D as a therapeutic immunomodulator in tuberculosis (TB) has been recognised for over 150 years, but has only recently returned to the centre of the research arena due to the increasing awareness of the global vitamin D deficiency epidemic. As early as birth a child is often deficient in vitamin D, which may not only affect their bone metabolism but also modulate their immune function, contributing to the increased susceptibility to many infections seen early in life. Recent studies have begun to explain the mechanisms by which vitamin D affects immunity. Antimicrobial peptides are induced in conjunction with stimulation of innate pattern recognition receptors enhancing immunity to particular infections. In contrast the role of vitamin D within the adaptive immune response appears to be more regulatory in function, perhaps as a mechanism to reduce unwanted inflammation. In this paper we focus on the effect of vitamin D on immunity to TB. Where much of the attention has been paid by past reviews to the role of vitamin D in adult TB patients, this paper, where possible, focuses on research in paediatric populations.

Serum 25-hydroxyvitamin D is associated with enhanced pneumococcal antibody levels in individuals with asthma

Recent studies suggest that vitamin D modulates innate immunity and reduces the risk of microbial infections. Little is known about the role of vitamin D in antipneumococcal immunity in individuals with asthma. We determined the correlation between serum 25-hydroxyvitamin D (25[OH]D) levels and pneumococcal antibody levels in individuals with asthma, atopic dermatitis, or allergic rhinitis, and atopic sensitization status. A cross-sectional study was conducted for 21 subjects with asthma and 23 subjects without asthma. Pearson's correlation coefficient between serum 25(OH)D concentrations and the number of positive serotype-specific antibody levels was calculated among individuals with and without asthma, atopic dermatitis, and/or allergic rhinitis and atopic sensitization status. The overall correlation between serum 25(OH)D concentrations and positive pneumococcal antibody levels in all subjects regardless of asthma was not significant (r = -0.14; p = 0.38). Stratified analysis results showed that there was a positive correlation between serum 25(OH)D concentrations and positive pneumococcal antibody levels in asthmatic patients (r = 0.45; p < 0.05) and an inverse correlation was observed in nonasthmatic patients (r = -0.53; p < 0.05). These trends were similar for subjects with and without atopic dermatitis and/or allergic rhinitis (r = 0.58 and p = 0.008 versus r = -0.63 and p = 0.001). Despite similar trends in the correlation between serum 25(OH)D and pneumococcal antibody concentrations among those with and without atopic sensitization status (r = 0.27 and p = 0.19 versus r = -0.41 and p = 0.08), they did not reach statistical significance. The 25(OH)D may enhance humoral immunity against Streptococcus pneumonia in subjects with atopic conditions but not without atopic conditions. Atopic conditions may have an important effect modifier in the relationship between serum 25(OH)D concentrations and immune function.

Towards prevention of vitamin D deficiency and beyond: knowledge gaps and research needs in vitamin D nutrition and public health

The North American Institute of Medicine (IOM) recently published their report on dietary reference intakes (DRI) for Ca and vitamin D. The DRI committee's deliberations underpinning this most comprehensive report on vitamin D nutrition to date benefited hugely from a much expanded knowledge base in vitamin D over the last decade or more. However, since their release, the vitamin D DRI have been the subject of intense controversy, which is largely due to the persistence of fundamental knowledge gaps in vitamin D. These can be identified at the levels of exposure, metabolism, storage, status, dose-response, function and beneficial or adverse health effects, as well as safe and effective application of intake recommendations at the population level through sustainable food-based approaches. The present review provides a brief overview of the approach used by the IOM committee to revise the DRI for vitamin D and to collate from a number of authoritative sources key knowledge gaps in vitamin D nutrition from the public health perspective. A number of research topics are outlined and data requirements within these are identified and mapped to the risk assessment framework used by the DRI committee. While not intended as an exhaustive list, it provides a basis for organising and prioritising research efforts in the area of vitamin D, which may offer a perspective on the major areas in need of attention. It is intended to be of use to researchers, national policy makers, the public health community, industry groups and other relevant stakeholders including funding institutions.