Risk factors for wheezing in infants born in Cuba

Fungal populations in the bedroom dust of children in Havana, Cuba, and its relationship with environmental conditions

The study of the fungal community composition in house dust is useful to assess the accumulative exposure to fungi in indoor environments. The objective of this research was to characterize the fungal diversity of house dust and its association with the environmental conditions of bedrooms. For this, the dust was collected from 41 bedrooms of children between the ages of 8 and 9 with a family history of asthma, residents of Havana, Cuba. The fungal content of each sample was determined by two methods: plate culture with malt extract agar and by direct microscopy. An ecological analysis was carried out from the fungal diversity detected. To describe the factors associated with the fungi detected, bivariate logistic regression was used. Through direct microscopy, between 10 and 2311 fragments of hyphae and spores corresponding mainly to Cladosporium, Coprinus, Curvularia, Aspergillus/Penicillium, Xylariaceae, and Periconia were identified. Through the culture, 0-208 CFU were quantified, where Aspergillus, Cladosporium, and Penicillium predominated. The culturability evidenced the differences between the quantification determined by both methods. A positive relationship was found between the type of cleaning of the furniture, the presence of trees in front of the bedroom, indoor relative humidity, indoor temperature, the presence of air conditioning, and natural ventilation with specific spore types and genera. The use of two different identification methods allowed to detect a greater fungal diversity in the residences evaluated. Monitoring the exposure to these fungal allergens in childhood can help to prevent sensitization in the allergic child, the development of asthma, and other respiratory diseases.

Prevalence and risk factors for wheeze, decreased forced expiratory volume in 1 s and bronchoconstriction in young children living in Havana, Cuba: a population-based cohort study

OBJECTIVES

Asthma has not been extensively studied in low-income and middle-income countries, where risk factors and access to treatment may differ from more affluent countries. We aimed to identify the prevalence of asthma and local risk factors in Havana, Cuba.

SETTING

Four municipalities in Havana, Cuba.

PARTICIPANTS

A population-based cohort study design of young children living in Havana, Cuba. Children were recruited from primary care centres at age 12-15 months.

PRIMARY AND SECONDARY OUTCOME MEASURES

Data on wheeze in the past 12 months, asthma treatment and environmental exposures collected regularly until the age of 6 years, when forced expiratory volume in 1 s (FEV₁) and reversibility to aerosolised salbutamol were also measured.

RESULTS

1106 children provided data at the age of 6 years old. The prevalence of wheeze in the previous 12 months was 422 (38%), and 294 (33%) of the study population had bronchodilatation of 12% or more in FEV₁ after administration of inhaled salbutamol. In the previous 12 months, 182 (16%) of the children had received inhaled corticosteroids, 416 (38%) salbutamol inhalers and 283 (26%) a course of systemic steroids.Wheeze in the first year and a family history of asthma were both positively associated with bronchodilatation to inhaled salbutamol (1.94%; 95% CI 0.81 to 3.08 and 1.85%; CI 0.14 to 3.57, respectively), while paracetamol use in the first year was associated with wheeze at 6 years (OR 1.64, 95% CI 1.14 to 2.35). There were large differences in FEV₁, bronchodilatation and risk of wheeze across different geographical areas.

CONCLUSIONS

Asthma is common in young children living in Havana, and the high prevalence of systemic steroids administrated is likely to reflect the underuse of regular inhaled corticosteroids. If replicated in other comparable low-income and middle-income countries, this represents an important global public health issue.

Prevalence of and factors associated with Helicobacter pylori infection in preschoolers in Havana, Cuba: A population-based study

INTRODUCTION

Helicobacter pylori (H. pylori) infection is usually acquired in childhood. In Cuba, its study in pediatric ages is a little explored field.

AIM

To identify the prevalence of the infection and its associated risk factors in 3-year-old children in Havana.

MATERIALS AND METHODS

An analytic, cross-sectional, epidemiologic analysis was conducted on 1,274 children belonging to the cohort of participants in the Natural History of Wheezing in Cuba study (HINASIC for its Spanish acronym) that were 3 years of age and provided a stool sample. H. pylori infection was identified by determining the H. pylori antigen (Ag) in stool, utilizing the commercial Spinreact kit, from Spain. The data were collected through a questionnaire applied by the researchers that included sociodemographic, environmental, and lifestyle variables, as well as infection from other parasites. Prevalence and the prevalence ratio with a 95% confidence interval were calculated and the dichotomous logistic regression analysis was employed.

RESULTS

The prevalence of positive H. pylori Ag was 5%. Sleeping together was the risk factor found (PR:1.27; 95% CI: 1.03-1.50). Protective factors were drinking water from water delivery trucks (PR: 0.16; 95% CI: 0.04-0.72) and living in a nuclear family unit (PR: 0.94; 95% CI: 0.85-0.99).

CONCLUSIONS

The prevalence of H. pylori infection in early childhood places Havana in an intermediate position at the international level. To control the infection, causal studies should be conducted and opportune interventions implemented.

Colostrum immunoglobulins and oxidative capacity may be affected by infant sex and maternal age and parity

Background/aim

The aims of this study were to determine the levels of the total antioxidant status (TAS), the total oxidant status (TOS), the oxidative stress index (OSI), and the concentration of immunoglobulin A (IgA) and M (IgM) in colostrum, and evaluate relationships between these parameters and maternal age, maternal parity, and infant sex.

Materials and methods

The analysis was performed in serum samples of colostrum which were collected from 90 mothers on the first day of lactation between 10:00 and 12:00 AM.

Results

The measurements established that no significant association existed between the TAS level of colostrum and parity, maternal age, or infant sex. However, mothers 18 to 30 years of age had significantly lower colostrum TOS and OSI levels compared with mothers older than 30 years of age. IgA and IgM values of the colostrum of primiparous mothers were significantly higher than those of multiparous mothers, whereas no correlations existed with the age of the mother. Additionally, significantly higher colostrum IgA and IgM values were observed in female infants fed colostrum compared with male infants.

Conclusion

In conclusion, sex-based hormonal changes in mothers during pregnancy may be associated with the different colostral immunoglobulin levels for male and female infants.

The association between dengue immunoglobulin G titres with previous clinical dengue infection and white cell counts in Cuban children: A population-based study

Background

The prevalence of dengue infection is increasing globally. There are few prospective population-based surveillance studies of the immunological and inflammatory consequences of exposure to dengue virus in young children.

Objective

To study the association between serologically confirmed prior medical diagnosis of dengue infection and blood measures of systemic inflammation with dengue virus immunoglobulin G levels.

Methods

A population-based study of healthy three-year old children living in Havana, Cuba.

Results

865 individuals provided a blood sample. Fourteen (1.6%) had a prior medical diagnosis of dengue infection, and 851 individuals had no prior medical diagnosis. There was no difference in the serum immunoglobulin G titres between these groups (Mann-Whitney test, p = 0.49). Total white cell count, blood neutrophil and eosinophil counts were linearly associated with a dengue immunoglobulin G value above the median value.

Conclusions

There was no difference between the dengue immunoglobulin G titres in young children who had previously had clinically proven dengue infection compared to those who had no diagnosis of prior infection. This may be a consequence of a relatively high prevalence of sub-clinical infection. A higher dengue immunoglobulin G level was positively associated with a range of inflammatory biomarkers, although these data cannot demonstrate a causal association.

Mora‐Faife E, García‐García G, del Valle‐Infante I, Gómez‐Marrero L, Britton J, Fogarty AW. The association of low birth weight with serum C reactive protein in 3-year-old children living in Cuba: A population-based prospective study

OBJECTIVE

Low birthweight is associated with a decreased risk of childhood leukemia and an increased risk of both cardiovascular disease and all-cause mortality in adult life. Possible biological mediators include systemic innate immunity and inflammation. We tested the hypothesis that birthweight was inversely associated with serum high sensitivity C reactive protein assay (hsCRP), a measure of both innate immunity and systemic inflammation.

METHODS

Data on birthweight and current anthropometric measures along with a range of exposures were collected at 1 and 3 years of age in a population-based cohort study of young children living in Havana, Cuba. A total of 986 children aged 3-years-old provided blood samples that were analyzed for serum hsCRP levels.

RESULTS

Nearly 49% of children had detectable hsCRP levels in their serum. Lower birthweight was linearly associated with the natural log of hsCRP levels (beta coefficient -0.70 mg L-1 per kg increase in birthweight, 95% CI: -1.34 to -0.06). This was attenuated but still present after adjustment for the child's sex and municipality (-0.65 mg L-1 per kg birthweight; 95% CI: -1.38 to +0.08). There were no associations between growth from birth or anthropometric measures at 3 years and systemic inflammation.

CONCLUSIONS

Birthweight was inversely associated with serum hsCRP levels in children aged 3 years living in Cuba. These observations provide a potential mechanism that is present at the age of 3 years to explain the association between low birthweight and both decreased childhood leukemia and increased cardiovascular disease in adults.

The Danish National Database for Asthma: establishing clinical quality indicators

Asthma is one of the most common chronic diseases worldwide affecting more than 300 million people. Symptoms are often non-specific and include coughing, wheezing, chest tightness, and shortness of breath. Asthma may be highly variable within the same individual over time. Although asthma results in death only in extreme cases, the disease is associated with significant morbidity, reduced quality of life, increased absenteeism, and large costs for society. Asthma can be diagnosed based on report of characteristic symptoms and/or the use of several different diagnostic tests. However, there is currently no gold standard for making a diagnosis, and some degree of misclassification and inter-observer variation can be expected. This may lead to local and regional differences in the treatment, monitoring, and follow-up of the patients. The Danish National Database for Asthma (DNDA) is slated to be established with the overall aim of collecting data on all patients treated for asthma in Denmark and systematically monitoring the treatment quality and disease management in both primary and secondary care facilities across the country. The DNDA links information from population-based disease registers in Denmark, including the National Patient Register, the National Prescription Registry, and the National Health Insurance Services register, and potentially includes all asthma patients in Denmark. The following quality indicators have been selected to monitor trends: first, conduction of annual asthma control visits, appropriate pharmacological treatment, measurement of lung function, and asthma challenge testing; second, tools used for diagnosis in new cases; and third, annual assessment of smoking status, height, and weight measurements, and the proportion of patients with acute hospital treatment. The DNDA will be launched in 2016 and will initially include patients treated in secondary care facilities in Denmark. In the nearby future, the database aims to include asthma diagnosis codes and clinical data registered by general practitioners and specialised practitioners as well.

Population-based weight loss and gain do not explain trends in asthma mortality in Cuba: A prospective study from 1964 to 2014

BACKGROUND

The increase in prevalence of obesity is a possible risk factor for asthma in developed countries. As the people of Cuba experienced an acute population-based decrease in weight in the 1990s, we tested the hypothesis that national weight loss and subsequent weight gain was associated a reciprocal changes in asthma mortality.

METHODS

Data were obtained on mortality rates from asthma and COPD in Cuba from 1964 to 2014, along with data on prevalence of obesity for this period. Joinpoint analysis was used to identify inflexion points in the data.

RESULTS

Although the prevalence of obesity from 1990 to 1995 decreased from 14% to 7%, over the same time period the rate of asthma mortality increased from 4.5 deaths per 100,000 population to 5.4 deaths per 100,000 population. In 2010, the obesity prevalence subsequently increased to 15% in 2010, while the asthma mortality rate dropped to 2.3 deaths per 100,000 population. The optimal model for fit of asthma mortality over time gave an increasing linear association from 1964 to 1995 (95% confidence interval for inflexion point: 1993 to 1997), followed by a decrease in asthma mortality rates from 1995 to 1999 (95% confidence interval for inflexion point: 1997 to 2002).

CONCLUSIONS

These national data do not support the hypothesis that population-based changes in weight are associated with asthma mortality. Other possible explanations for the large decreases in asthma mortality rates include changes in pollution or better delivery of medical care over the same time period.

What have studies of non-industrialized countries told us about the cause of allergic disease?

The increase in allergic diseases that was observed in countries that had experienced rapid economic growth since the mid-20th century initiated a search for environmental exposures that may explain these phenomena that continues to the present day. Societies that are in the earlier stages of the process of industrialization provide an opportunity to compare the initial stages of economic development and the lifestyle changes that may accompany this, with other communities whose way of life may not have changed appreciably for centuries. These studies have consistently demonstrated higher levels of allergic disease in the relatively affluent populations compared with those who maintain a more traditional lifestyle. Environmental changes that have emerged from these studies that may modify the risk of allergic disease include microbial exposures including parasite infection, pollution, diet and obesity. In addition, food and drug allergies represent a neglected area of research in these countries that may be causing a relatively high burden of disease.

Epidemiological aspects of and risk factors for wheezing in the first year of life

OBJECTIVE:

To determine, in a sample of infants, the prevalence of and risk factors for occasional wheezing (OW) and recurrent wheezing-wheezy baby syndrome (WBS).

METHODS:

Parents of infants (12-15 months of age) completed the International Study of Wheezing in Infants questionnaire.

RESULTS:

We included 1,269 infants residing in the city of Blumenau, Brazil. Of those, 715 (56.34%) had a history of wheezing, which was more common among boys. The prevalences of OW and WBS were 27.03% (n = 343) and 29.31% (n = 372), respectively. On average, the first wheezing episode occurred at 5.55 ± 2.87 months of age. Among the 715 infants with a history of wheezing, the first episode occurred within the first six months of life in 479 (66.99%), and 372 (52.03%) had had three or more episodes. Factors associated with wheezing in general were pneumonia; oral corticosteroid use; a cold; attending daycare; having a parent with asthma or allergies; mother working outside the home; male gender; no breastfeeding; and mold. Factors associated with WBS were a cold; physician-diagnosed asthma; ER visits; corticosteroid use; pneumonia; bronchitis; dyspnea; attending daycare; bronchodilator use; having a parent with asthma; no breastfeeding; mother working outside the home; and a dog in the household.

CONCLUSIONS:

The prevalence of wheezing in the studied population was high (56.34%). The etiology was multifactorial, and the risk factors were intrinsic and extrinsic (respiratory tract infections, allergies, attending daycare, and early wheezing). The high prevalence and the intrinsic risk factors indicate the need and the opportunity for epidemiological and genetic studies in this population. In addition, mothers should be encouraged to prolong breastfeeding and to keep infants under six months of age out of daycare.

Prevalence and risk factors for wheezing in Salvador, Brazil: a population-based study

BACKGROUND

Wheezing is one of the most frequent causes of visit to emergency rooms among children. However, data on wheezing burden are mostly provided at healthcare setting, and particularly only for infants.

AIMS

We sought to estimate the prevalence of wheezing in children under 4 years and to assess potential risk factors in the community.

DESIGN

This was a cross-sectional analysis of a population-based cohort study.

METHODS

The sample comprised children aged <4 years living in Salvador, Brazil. Data were collected via home visits when the parents/guardians were interviewed. Data were recorded on standardized forms.

RESULTS

Of 1534 children, mean age was 21 ± 14 months (minimum 3 days; maximum 47 months; 6% <2 months); 780 (51%) were males and 501 [33%; 95% confidence interval (95% CI): 30-35%] reported wheezing in the last 12 months. Among wheezers, 321 (64%) had occasional wheezing. Overall, 180 (12%; 95% CI: 10-14%) had recurrent wheezing and 157 (10%; 95% CI: 9-12%) had asthma. For children in the first, second, third and fourth year of life wheezing was reported in 23, 41, 34 and 37%, respectively. Mother atopic-related disease was independently associated with recurrent wheezing (AdjPR[95% CI]: 1.54 [1.12-2.11]) and asthma (AdjPR[95% CI]: 1.54 [1.10-2.16]). Smoker at home (AdjPR[95% CI]: 1.34 [1.07-1.67]) and low birth weight (AdjPR[95%CI]: 1.38 [1.05-1.81]) were independently associated with occasional wheezing.

CONCLUSIONS

One-third of under 4 years reported wheezing; history of mother's atopic-related disease was an independent risk factor for recurrent wheezing and asthma; smoker at home and low birth weight were independent risk factors for occasional wheezing.

What are the main environmental exposures associated with elevated IgE in Cuban infants? A population-based study

OBJECTIVE

Immunoglobulin E (IgE) plays a key role in allergy disease pathogenesis, but little is known about the environmental factors associated with higher IgE levels in infants. The aim of this study was to determine the risk factors for elevated serum total IgE infants living in Havana.

METHODS

Eight hundred and seventy-seven infants provided blood samples. Data on allergic disease symptoms and a wide range of exposures were collected.

RESULTS

The median IgE was 35 IU/ml (interquartile range 13-96). The risk of having an IgE level above the median was higher for children who had been breastfed for 4 months or more (adjusted odds ratio (OR) 1.28; 95% confidence interval (CI): 1.02-1.61) and for children who reported cockroaches in their home (OR 1.30; 95% CI: 1.03-1.63). The risk was lower for children whose mother was in paid employment (OR 0.73; 95% CI: 0.54-0.97 compared with those who did not), for children living in homes where gas and electricity were used for cooking (OR 0.45; 95% CI: 0.32-0.62 compared with electricity only) and for children with domestic pets at birth (OR 0.83; 95% CI: 0.70-1.00). There was no association between paracetamol use and serum IgE levels.

CONCLUSIONS

Associations between gas fuel use and maternal employment indicate that IgE levels in early life are lower in children who may be living in relative affluence. The discrepancy in the effect of early exposure to pets or cockroaches may reflect differences in these allergens, or be confounded by relative affluence. Further investigation of this cohort will determine how these effects translate into the expression of allergic disease in later life.

Risk factors for eczema in infants born in Cuba: a population-based cross-sectional study

Background

There is a concern that allergic disease in childhood is higher than expected in Cuba. The aim of this study was to determine the risk factors for eczema of infants aged 12–15 months living in Havana.

Methods

We used a cross-sectional epidemiological study design. Data on eczema symptoms and a wide range of lifestyle factors were collected by researcher administered questionnaires.

Results

Data were collected on 1956 children (96% response rate), of whom 672 (34%) were reported as having had eczema. Independent risk factors for eczema included young maternal age (adjusted odds ratio (OR) 0.98 per additional year of age; 95% confidence interval (CI) 0.97-0.99), child’s weight (OR 1.13 per additional kg; 95% CI: 1.03-1.25), insect sting allergy (OR 2.11; 95% CI: 1.33-3.35), rodents in the home (OR 1.39; 95% CI: 1.10-1.76), attendance at childcare facilities (OR 1.34: 95% CI: 1.05-1.70) and self-reported mould in the home (OR 1.23; 95% CI: 1.07-1.41). Infant exposure to paracetamol was associated with an increased risk of eczema even after adjustment for wheeze (OR 1.22; 95% CI: 1.03-1.46).

Conclusion

Despite a very different culture and environment, the consistency of these findings with those from more economically developed countries suggests potential causal associations. The association with paracetamol, even after adjustment for wheeze, suggests that intervention studies are required in young infants, to ascertain if this commonly used anti-pyretic medication increases allergic disease.