Age at bacille Calmette–Guérin vaccination and risk of allergy and asthma

BACKGROUND: It has been proposed that early age at bacille Calmette-Guérin (BCG) vaccination protects against the development of allergy. OBJECTIVE: To study whether early age at BCG vaccination was associated with a decreased risk of atopy, allergic rhinitis, and asthma compared to BCG vaccination at later ages in childhood. METHODS: The occurrence of atopy, allergic rhinitis, and asthma was studied in nearly 2000 women participating in the Danish National Birth Cohort study. Detailed information on age at BCG vaccination (age 0-15 years) was available from school health records. Atopic status was assessed serologically by a specific response to 11 common inhalant allergens using serum samples obtained from the women during the period 1997-2001. Information on allergic rhinitis and asthma was available from telephone interviews. RESULTS: Approximately 85% of the women had been BCG-vaccinated. Age at BCG vaccination was not associated with risk of atopy, allergic rhinitis, or asthma. The odds ratio of atopy, allergic rhinitis, and asthma associated with being vaccinated during the first year of life was 1.05 (95% CI 0.71-1.56), 1.42 (95% CI 0.85-2.36), and 1.71 (95% CI 0.91-3.20), respectively, compared with being vaccinated at the age of 7 years. Adjustment for birth cohort, sibship size, age of the woman's mother at birth, and social class in childhood did not affect the results. CONCLUSION: Our findings suggest that age at BCG vaccination in childhood does not influence the development of allergy or asthma.     

Association of active and passive smoking with allergic disorders in pregnant Japanese women: baseline data from the Osaka Maternal and Child Health Study.

BACKGROUND: Evidence remains inconclusive as to whether smoking is a risk factor for allergic disorders in adults. OBJECTIVE: To investigate the relationship between active and passive smoking exposure and allergic disorders in pregnant Japanese women. METHODS: This cross-sectional study included 1,002 pregnant women. Participants were classified as having asthma after the age of 18 years if they had used an asthma medication at any time after reaching the age of 18 years. Current atopic eczema and allergic rhinitis (including cedar pollinosis) were defined as being present if participants had received any drug treatment during the previous 12 months. Adjustment was made for age; gestation; parity; family history of asthma, atopic eczema, and allergic rhinitis; indoor domestic pets; family income; education; and the mite antigen level in house dust. RESULTS: Current smoking, but not environmental tobacco smoke exposure, was independently related to an increased prevalence of asthma after the age of 18 years (adjusted odds ratio [OR], 2.66; 95% confidence interval [CI], 1.30-5.38). A significant positive association of current passive smoking exposure at home (adjusted OR, 1.89; 95% CI, 1.10-3.30) and at work (adjusted OR, 2.50; 95% CI, 1.29-4.76) with the prevalence of current allergic rhinitis was observed, whereas no measurable association with active smoking exposure was found. Neither active nor passive smoking was statistically significantly related to the prevalence of current atopic eczema. CONCLUSIONS: These findings suggest that active smoking and environmental tobacco smoke exposure may increase the likelihood of asthma and allergic rhinitis, respectively, in pregnant Japanese women.     

Menstrual irregularity and asthma and lung function

BACKGROUND: Oligomenorrhea was associated with more asthma (Respiratory Health in Northern Europe study), but a possible association with lung function has not been investigated previously. OBJECTIVE: To investigate whether oligomenorrhea was related to lung function and asthma, and whether body mass index and physical activity modified associations. METHODS: Women age 28 to 44 years (n = 1631) participating in the European Community Respiratory Health Survey were included. Women who were taking exogenous sex hormones, were pregnant, or had recently given birth were excluded. RESULTS: Long or irregular menstrual cycles were reported by 313 women (19%). Oligomenorrhea was significantly associated with more asthma symptoms (odds ratio [OR], 1.76; 95% CI, 1.29-2.40), allergic asthma (OR, 2.46; 95% CI, 1.43-4.23), and lower forced vital capacity (FVC; adjusted difference, 63 mL; 95% CI, -124 to -1). When excluding women using asthma medication, very lean women, or women exercising daily, these associations remained significant. Effects of oligomenorrhea were additive to those of body mass index (BMI) on asthma and FVC. Asthma symptoms increased significantly with BMI. FVC and FEV(1) increased with BMI until 25 kg/m(2) and thereafter decreased with increasing BMI. Excluding women exercising daily, asthma symptoms increased significantly with decreasing physical activity (OR, 1.09; 95% CI, 1.001-1.19) per category of physical activity) independently of oligomenorrhea. Among women exercising daily, oligomenorrhea predicted very high risk for asthma symptoms (OR, 12.6; 95% CI, 3.7-43). CONCLUSION: Women with oligomenorrhea have reduced lung function and more asthma, particularly allergic asthma, independent of BMI and physical activity. Airways pathology may have not only a hormonal but also a metabolic component. CLINICAL IMPLICATIONS: Women with oligomenorrhea should be investigated with regard to asthma and lung function. Underlying metabolic disturbance should be considered in asthma.     

Pet-keeping in childhood and adult asthma and hay fever: European community respiratory health survey

BACKGROUND: Whether pet-keeping early in life protects against or promotes allergy remains unclear. OBJECTIVE: Our aim was to examine the effects of childhood pet-keeping on adult allergic disease in a large international population-based study, including information on sensitization, adult pet-keeping, and pet prevalence in the populations. METHODS: We used information from structured interviews (n = 18,530) and specific IgE to common aeroallergens in blood samples (n = 13,932) from participants in the European Community Respiratory Health Survey (ECRHS) to analyze the associations between keeping pets and adult asthma and hay fever. RESULTS: Keeping cats in childhood was associated with asthma only among atopic subjects, an association that varied between centers (P =.002) and was stronger where cats where less common (< 40% cats: odds ratio(wheeze) [OR(wheeze)] = 1.84, 95% CI = 1.31-2.57; 40%-60% cats: OR(wheeze) = 1.33, 95% CI = 1.10-1.61; > or =60% cats: OR(wheeze) = 0.98, 95% CI = 0.73-1.33). Dogs owned in childhood or adulthood were associated with asthma among nonatopic subjects (childhood: OR(wheeze) = 1.28, 95% CI = 1.13-1.46; adulthood: OR(wheeze) = 1.31, 95% CI = 1.14-1.51; both: OR(wheeze) = 1.69, 95% CI = 1.40-2.04). In atopic subjects, those who had owned dogs in childhood had less hay fever (OR = 0.85; 95% CI = 0.73-0.98) and no increased risk of asthma (OR(wheeze) = 1.01, 95% CI = 0.87-1.17). Respiratory symptoms were more common in subjects who had owned birds during childhood (OR(wheeze) = 1.12; 95% CI = 1.02-1.23) independent of sensitization. CONCLUSIONS: The effects of pet-keeping in childhood varied according to the type of pet, the allergic sensitization of the individual, and the wider environmental exposure to allergen. Cats owned in childhood were associated with more asthma in sensitized adults who grew up in areas with a low community prevalence of cats. Dogs owned in childhood seemed to protect against adult allergic disease but promote nonallergic asthma.     

Time to pregnancy and multiple births

BACKGROUND: Mothers of multiples are alleged to be more fecund than mothers of singletons. Some authors have suggested monitoring twinning rates for assessing temporal changes in a population's reproductive health. METHODS: Using a nested case-control design, we estimated the odds of a multiple birth in relation to fecundity in the US Collaborative Perinatal Project inclusive of 8546 pregnant women who reported a known time-to-pregnancy (TTP) upon enrolment in the cohort, 1959-1966. Case mothers comprised 81 women giving birth to twins/triplets; control mothers comprised 243 women giving birth to singletons matched to case mothers on maternal age at a ratio of 3:1. The odds ratio (OR) for a multiple birth within 6 months of trying adjusting for maternal age and prior pregnancies was estimated using logistic regression. Discrete time Cox regression analysis was also utilized to estimate the fecundability OR. RESULTS: Women with a TTP of 6 months [OR=1.95; 95% confidence interval (95% CI)=1.09-3.51]. Excluding pregnancies after 13+ months resulted in a loss of precision (OR=2.14; 95% CI=0.90-5.04). CONCLUSIONS: These data support higher fecundity among mothers of multiples than mothers of singletons.     

Effect of maternal HIV and malaria infection on pregnancy and perinatal outcome in Zimbabwe

OBJECTIVE: To investigate the effect of isolated or concomitant infection with malaria and HIV on pregnancy and neonatal outcome. METHODS: Data were collected on pregnant women admitted during the rainy seasons in the obstetric division of a district referral hospital in northern Zimbabwe in 2000 and 2001. The effects of malaria and HIV infection were determined by multivariate analysis. RESULTS: The prevalence of HIV seropositivity and symptomatic malaria in 986 pregnant women was 8.3% and 14.7%, respectively. HIV-infected women were more likely to develop malaria attacks during pregnancy than seronegative women (odds ratio [OR] = 3.96, 95% confidence interval (CI): 2.42-6.46). Malaria and HIV infections were associated with increased risk of stillbirth (OR = 4.74, 95% CI: 1.34-16.78) and preterm delivery (OR = 4.10, 95% CI: 2.17-7.75), respectively. They were independently associated with increased risk of low birth weight (malaria: OR = 10.09, 95% CI: 6.50-15.65; HIV: OR = 3.16, 95% CI: 1.80-5.54) and very low birth weight (malaria: OR = 5.04, 95% CI: 1.00-25.43; HIV: OR = 10.74, 95% CI: 2.12-54.41), low Apgar score (malaria: OR = 4.45, 95% CI: 1.42-13.94; HIV: OR = 5.94, 95% CI: 1.66-21.30), and fetal growth restriction (malaria: OR = 3.98, 95% CI: 2.51-6.30; HIV: OR = 4.07, 95% CI: 2.40-6.92). Dual infection with malaria and HIV was associated with increased risk of maternal, perinatal, and early infant death. CONCLUSIONS: Women with single HIV or malaria infection have a significantly increased risk of adverse outcomes of pregnancy and childbirth. Dual infection has additional detrimental effects on maternal and infant survival in an area where HIV and malaria coexist.     

Risk of Pregnancy Complications and Low Birth Weight Offsprings in Korean Women With Rheumatic Diseases: A Nationwide Population-Based Study

BackgroundTo determine the risk of pregnancy complications and adverse offspring outcomes in Korean women with rheumatic diseases (RDs).MethodsWomen aged 20–44 years with pregnancies ending in delivery were identified from the National Health Insurance Service-National Health Information Database (2009–2016). Women with RD including systemic lupus erythematosus (SLE), seropositive rheumatoid arthritis (SPRA), and ankylosing spondylitis (AS) (n = 4,284) were age-matched with controls (n = 26,023). Outcome variables included threatened abortion (TA), preterm birth (PB), preeclampsia/eclampsia (PE/E), intrauterine growth retardation (IGR), urinary tract infection, low birth weight (LBW) offsprings, and offspring death within 1 year of birth.ResultsWomen with RDs had increased risks for cesarean section delivery (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.4–1.6), TA (OR, 1.4; 95% CI, 1.2–1.5), PB (OR, 2.4; 95% CI, 1.9–3.2), PE/E (OR, 4.4; 95% CI, 3.3–5.9), and IGR (OR, 2.4; 95% CI, 2.0–3.1) than the controls. The risk of pregnancy complications was increased in SLE and SPRA pregnancies but not in AS pregnancies. Offsprings of women with RDs had an increased risk of LBW (OR, 4.0; 95% CI, 3.2–4.9). The offspring mortality rate within 1 year of birth was higher in women with RDs (6.2/10,000 persons) than in the controls (4.9/10,000 persons).ConclusionWomen with RDs are at a risk of developing pregnancy complications, and the risk of LBW offsprings and offspring death within 1 year of birth is increased in these women. Therefore, this population requires special attention during their childbearing years.     

Rhinitis therapy and the prevention of hospital care for asthma: a case-control study

BACKGROUND: Although clinical trials have demonstrated that rhinitis therapy improves subjective and objective measures of asthma, it is uncertain whether treatment of allergic rhinitis significantly affects the frequency of asthma exacerbations. OBJECTIVE: The objective of this study was to determine whether treatment with intranasal corticosteroids and/or second-generation antihistamines is associated with changes in rates of asthma exacerbations resulting in emergency room visits and/or hospitalizations in patients with asthma and allergic rhinitis. METHODS: This was a nested, case-control study. RESULTS: Treatment with either nasal corticosteroids or second-generation antihistamines was associated with a lower risk of asthma-related emergency room treatment and hospitalization (adjusted odds ratio [OR], 0.51; 95% CI, 0.34 to 0.77 and 0.34, 0.18 to 0.62, respectively). Patients who used nasal corticosteroids had a significantly lower risk of both asthma-related emergency room treatment and hospitalization (adjusted OR, 0.75; 95% CI, 0.62 to 0.91 and 0.56, 0.42 to 0.76, respectively), whereas there was a trend toward lower risk of emergency room treatment and hospitalization in patients who used second-generation antihistamines (adjusted OR, 0.88; 95% CI, 0.62 to 1.26 and 0.68, 0.40 to 1.14, respectively). Combined treatment with both medications was associated with a further lowering of the risk of both emergency room treatment and hospitalization (adjusted OR, 0.37; 95% CI, 0.19 to 0.73 and 0.22, 0.07 to 0.63). CONCLUSIONS: In patients with asthma, treatment of concomitant allergic rhinitis was associated with significant reductions in risk of emergency room treatment and hospitalization for asthma.     

The impact of climate and traffic-related NO2 on the prevalence of asthma and allergic rhinitis in Italy

BACKGROUND: Environmental factors are likely to be involved in explaining the wide geographical variation in asthma and atopic diseases that has been documented in many recent epidemiological studies. AIM: To evaluate to what extent climate and outdoor NO2 pollution can explain the geographical variation in the prevalence of asthma and allergic rhinitis, and to estimate the relative risk for exposure to different levels of these two factors. METHODS: The impact of climate and long-term exposure to nitrogen dioxide (NO2) pollution on asthma and allergic rhinitis was assessed in a cross-sectional study, carried out during 1998 to 2000 on young adults aged 20 to 44 years (n = 18 873), living in 13 areas from two different Italian climatic regions (subcontinental and Mediterranean). RESULTS: Mediterranean areas had a significantly higher prevalence of asthma-like symptoms (P < 0.001), higher annual mean temperature (16.2 degrees C vs. 12.9 degrees C), lower temperature range (16.0 C degrees vs. 22.1 degrees C) and lower NO2 levels (31.46 microg/m3 vs. 57.99 microg/m3) than subcontinental ones. Mediterranean climate was associated with an increased risk of wheeze (OR = 1.23; 95% CI 1.13 to 1.35), tightness in the chest (OR = 1.21; 95% CI 1.11 to 1.33), shortness of breath (OR = 1.21; 95% CI 1.08 to 1.36) and asthma attacks (OR = 1.19; 95% CI 1.07 to 1.31). After adjusting for climate, an increase of 18.3 microg/m3 in NO2 levels moderately increased the risk of asthma attacks (OR = 1.13; 95% CI 0.98 to 1.32), tightness in the chest (OR = 1.11; 95% CI 0.98 to 1.26) and wheeze (OR = 1.11; 95% CI 0.96 to 1.28). When the levels of outdoor NO2 exposure rose, the prevalence of allergic rhinitis increased significantly in the Mediterranean region (OR = 1.38; 95% CI 1.12 to 1.69), but not in the subcontinental one (OR = 1.03; 95% CI 0.83 to 1.28). CONCLUSION: Our results show that the prevalence of asthma increases when annual mean temperature increases and temperature range decreases. Furthermore, climate interacts with NO2 outdoor exposure, increasing the risk for allergic rhinitis in people exposed to high stable temperatures. A long-term role for the effect of traffic pollution on asthma is also suggested.     

Relevance of the hygiene hypothesis to early vs. late onset allergic rhinitis

Introduction The hygiene hypothesis proposes that reduced exposure to infections in early life increases the risk of developing allergic conditions including allergic rhinitis. We examined the association between markers of the hygiene hypothesis and allergic rhinitis that developed before 7 years of age and allergic rhinitis that developed after 7 years of age. Methods The Tasmanian Longitudinal Health Study (TAHS) is a population‐based cohort (n=8583) study of respiratory disease. Participants have been followed from 7 to 44 years of age. Information on potential risk factors, allergies and respiratory symptoms was collected longitudinally. Using multi‐nomial logistic regression, exposure to siblings, infections, tonsillectomy and farm residence during childhood were examined as risk factors for allergic rhinitis that developed before or after 7 years of age. All analyses were adjusted for gender, maternal and paternal atopy, mother's age at participant's birth, paternal socio‐economic status in 1968 and personal socio‐economic status in 2004. Results Greater cumulative exposure to siblings before the age of 2 years was strongly inversely associated with early onset allergic rhinitis (<1 year sib exposure: OR=0.6, 95% CI 0.3–1.0; 1–3 years sib exposure: OR=0.6, 95% CI 0.4–0.9; >3 years sib exposure: OR=0.4, 95% CI 0.3–0.8) less so with later onset allergic rhinitis. The risk of early onset allergic rhinitis decreased with increasing viral infections (OR=0.7, 95% CI 0.5–0.9) during childhood. Having a tonsillectomy before 7 years of age increased the risk of early onset allergic rhinitis (OR=1.7, 95% CI 1.2–2.5). None of these factors was associated with later onset allergic rhinitis. Conclusions Exposures relevant to the hygiene hypothesis were important predictors for the development of early onset but less so for later onset allergic rhinitis. The exact mechanisms by which siblings and infections protect against allergic rhinitis are unclear. The stronger findings for earlier onset allergic rhinitis suggest that family structure and infections have most impact on disease risk in early life. Further research should focus on early onset allergic rhinitis when exploring causal explanations for any sibling effect.     

Seeking Health Information Online: Association With Young Australian Women’s Physical,Mental, and Reproductive Health

Background

Relatively little is known about the extent to which young adults use the Internet as a health information resource and whether there are factors that distinguish between those who do and do not go online for health information.

Objective

The aim was to identify the sociodemographic, physical, mental, and reproductive health factors associated with young women’s use of the Internet for health information.

Methods

We used data from 17,069 young women aged 18-23 years who participated in the Australian Longitudinal Study on Women’s Health. Multivariable logistic regression was used to estimate the association between sociodemographic, physical, mental, and reproductive health factors associated with searching the Internet for health information.

Results

Overall, 43.54% (7433/17,069) of women used the Internet for health information. Women who used the Internet had higher odds of regular urinary or bowel symptoms (OR 1.44, 95% CI 1.36-1.54), psychological distress (very high distress: OR 1.24, 95% CI 1.13-1.37), self-reported mental health diagnoses (OR 1.16, 95% CI 1.09-1.23), and menstrual symptoms (OR 1.25, 95% CI 1.15-1.36) than women who did not use the Internet for health information. Internet users were less likely to have had blood pressure checks (OR 0.85, 95% CI 0.78-0.93) and skin cancer checks (OR 0.90, 95% CI 0.84-0.97) and to have had a live birth (OR 0.74, 95% CI 0.64-0.86) or pregnancy loss (OR 0.88, 95% CI 0.79-0.98) than non-Internet users.

Conclusions

Women experiencing “stigmatized” conditions or symptoms were more likely to search the Internet for health information. The Internet may be an acceptable resource that offers “anonymized” information or support to young women and this has important implications for health service providers and public health policy.     

Respiratory illnesses in early life and asthma and atopy in childhood

BACKGROUND: The relation between respiratory illnesses in early life and the development of asthma and atopy in childhood is incompletely understood. OBJECTIVE: We sought to examine the relationship between respiratory illnesses in early life and atopic diseases at school age. METHODS: We performed a prospective birth cohort study of the relationship between respiratory illnesses in the first year of life and asthma, atopy (sensitization to >or=1 allergen), and allergic rhinitis at school age in 440 children with a parental history of atopy. Logistic regression was used to examine the relationship between respiratory illnesses and asthma, atopy, and allergic rhinitis. The relationship between respiratory illnesses in early life and repeated measures of wheezing between the ages of 1 and 7 years was investigated by using a proportional hazards models. RESULTS: Physician-diagnosed croup (adjusted odds ratio [OR], 0.30; 95% CI, 0.12-0.72) and having 2 or more physician-diagnosed ear infections (adjusted OR, 0.58; 95% CI, 0.35-0.98) in the first year of life were inversely associated with atopy at school age. Physician-diagnosed bronchiolitis before age 1 year was significantly associated with asthma at age 7 years (adjusted OR, 2.77; 95% CI, 1.23-6.22). Recurrent nasal catarrh (>or=3 episodes of a runny nose) in the first year of life was associated with allergic rhinitis at age 7 years (adjusted OR, 2.99; 95% CI, 1.03-8.67). CONCLUSION: The relationship between early-life respiratory illnesses and asthma and atopy is complex and likely dependent on the type of infection and immune response it initiates. CLINICAL IMPLICATIONS: Certain respiratory illnesses in early life modify the risk of atopy and asthma at school age.     

Polymorphisms in the IL4 gene, smoking, and rhinoconjunctivitis in Japanese women: The Kyushu Okinawa Maternal and Child Health Study

Epidemiological evidence on the relationship between IL4 single nucleotide polymorphisms (SNPs) and allergic rhinitis is limited. We conducted a case-control study to investigate this issue in young adult Japanese women. Included were 393 women who met the criteria of the International Study of Asthma and Allergies in Childhood (ISAAC) for rhinoconjunctivitis. Controls were 703 women without rhinoconjunctivitis based on the ISAAC criteria who had not been diagnosed with allergic rhinitis and/or asthma by a doctor. Compared with the TT genotype of IL4 SNP rs2227284, the GG genotype, occurring in 10.2% of control subjects, was significantly inversely associated with the risk of rhinoconjunctivitis: the adjusted OR was 0.60 (95% CI: 0.37-0.98). There were no significant relationships between SNP rs2243250, rs2070874, or rs2243290 and rhinoconjunctivitis. None of the haplotypes were significantly related to rhinoconjunctivitis. A significant inverse relationship between the combination of the TG and GG genotypes of SNP rs2227284 and rhinoconjunctivitis was observed in women who had never smoked, but not in those who had ever smoked (P for interaction=0.11). This is the first study to demonstrate a significant relationship between IL4 SNP rs2227284 and rhinoconjunctivitis. Smoking may modify the relationship between SNP rs2227284 and rhinoconjunctivitis.     

Risk Factors of Acoustic Neuroma: Systematic Review and Meta-Analysis

PurposeMany epidemiological studies have investigated environmental risk factors for the development of acoustic neuroma. However, these results are controversial. We conducted a meta-analysis of case-control studies to identify any potential relationship between history of noise exposure, smoking, allergic diseases, and risk of acoustic neuroma.ResultsEleven case-control studies were included in our meta-analysis. Acoustic neuroma was found to be associated with leisure noise exposure [odds ratio (OR)=1.33, 95% confidence interval (CI): 1.05–1.68], but not with occupational noise exposure and ever noise exposure (OR=1.20, 95% CI: 0.84–1.72 and OR=1.15, 95% CI: 0.80–1.65). The OR of acoustic neuroma for ever (versus never) smoking was 0.53 (95% CI: 0.30–0.94), while the subgroup analysis indicated ORs of 0.95 (95% CI: 0.81–1.10) and 0.49 (95% CI: 0.41–0.59) for ex-smoker and current smoker respectively. The ORs for asthma, eczema, and seasonal rhinitis were 0.98 (95% CI: 0.80–1.18), 0.91 (95% CI: 0.76–1.09), and 1.52 (95% CI: 0.90–2.54), respectively.ConclusionOur meta-analysis is suggestive of an elevated risk of acoustic neuroma among individuals who were ever exposed to leisure noise, but not to occupational noise. Our study also indicated a lower acoustic neuroma risk among ever and current cigarette smokers than never smokers, while there was no significant relationship for ex-smokers. No significant associations were found between acoustic neuroma and history of any allergic diseases, such as asthma, eczema, and seasonal rhinitis.     

Which aspects of the farming lifestyle explain the inverse association with childhood allergy?

BACKGROUND: Farmers' children have a reduced prevalence of allergic disorders. The specific protective environmental factors responsible are not yet identified. OBJECTIVE: We sought to determine whether farmers' children in the rural county of Shropshire, England, have a reduced risk of atopy and, if so, to identify the factors responsible. METHODS: The Study of Asthma and Allergy in Shropshire was a 2-stage cross-sectional study. In stage 1 a questionnaire to elicit allergic status, diet, and farming exposure was completed by the parents of 4767 children. In stage 2 a stratified subsample of 879 children underwent skin prick testing and measurement of domestic endotoxin. RESULTS: Compared with rural nonfarming children, farmers' children had significantly less current asthma symptoms (adjusted odds ratio (OR), 0.67; 95% CI, 0.49-0.91; P = .01) and current seasonal allergic rhinitis (adjusted OR, 0.50; 95% CI, 0.33-0.77; P = .002) but not current eczema symptoms (adjusted OR, 0.91; 95% CI, 0.68-1.21; P = .53) or atopy (adjusted OR, 0.68; 95% CI, 0.40-1.16; P = .15). In contrast, current unpasteurized milk consumption was associated with significantly less current eczema symptoms (adjusted OR, 0.59; 95% CI, 0.40-0.87; P = .008) and a greater reduction in atopy (adjusted OR, 0.24; 95% CI, 0.10-0.53; P = .001). The effect was seen in all children, independent of farming status. Unpasteurized milk consumption was associated with a 59% reduction in total IgE levels (P < .001) and higher production of whole blood stimulated IFN-gamma (P = .02). CONCLUSION: Unpasteurized milk consumption was the exposure mediating the protective effect on skin prick test positivity. The effect was independent of farming status and present with consumption of infrequent amounts of unpasteurized milk. CLINICAL IMPLICATIONS: Unpasteurized milk might be a modifiable influence on allergic sensitization in children.     

Mode of delivery and risk of allergic rhinitis and asthma

BACKGROUND: It has been hypothesized that cesarean section might increase the risk of developing allergic disease by depriving the fetus and newborn of exposure to maternal microflora. Furthermore, it has been suggested that complicated modes of delivery might be associated with an increased risk of asthma. OBJECTIVE: The purpose of this investigation was to study whether cesarean section and other complicated modes of delivery are associated with an increased risk of allergic rhinitis or asthma. METHODS: Information on self-reported allergic rhinitis, asthma ever, current asthma, and occupation was obtained from 9722 singleton women born in Denmark during the period 1973-1977 who participated in a national cohort study during the period 1997-2001. For these women, information was available on mode of delivery (spontaneous delivery, cesarean section, vacuum extraction, or other complicated mode of delivery, such as rotation/traction or use of forceps), gestational age, birth weight, and length at birth from the Danish Medical Birth Register. Information on parity and maternal age was obtained from the Danish Civil Registration System. RESULTS: The odds ratios (ORs) of allergic rhinitis were 1.16 (95% CI, 0.90-1.49) for cesarean section and 1.06 (95% CI, 0.85-1.32) for other complicated modes of delivery in comparison with spontaneous delivery. The corresponding ORs of asthma ever were 1.33 (95% CI, 1.02-1.74) and 1.18 (95% CI, 0.94-1.49) for cesarean section and other complicated modes of delivery, respectively, and the ORs of current asthma were 1.22 (95% CI, 0.87-1.73) and 1.26 (95% CI, 0.94-1.68), respectively, in comparison with spontaneous delivery. CONCLUSIONS: Our findings do not support the hypothesis that cesarean section or other complicated modes of delivery are associated with the development of allergic rhinitis. However, there might be a positive association with development of asthma--in particular, for cesarean section--that was not explained by gestational age, birth weight, ponderal index, smallness for gestational age, parity, maternal age, or occupation.     

Randomized trial of vitamin supplements in relation to vertical transmission of HIV-1 in Tanzania

BACKGROUND: Observational studies suggest that poor nutritional status among HIV-infected pregnant women is associated with a higher risk of vertical transmission of HIV. METHODS: We randomized 1083 pregnant women infected with HIV-1 in a double-blind, placebo-controlled trial to examine the effects of supplements of vitamin A and/or multivitamins (excluding vitamin A) using a 2-x-2 factorial design. We report the effects of the supplements on HIV infection defined using polymerase chain reaction (PCR), or death up to 6 weeks postpartum. RESULTS: Of babies in the multivitamin arm 38, (10.1%) were HIV-positive at birth compared with 24 (6.6%) in the no-multivitamin arm (relative risk [RR] = 1.54; 95% CI, 0.94-2.51; p = .08). Of babies born to mothers in the vitamin A arm, 38 (10.0%) were HIV-positive at birth compared with 24 (6.7%) in the no-vitamin A arm (RR, 1.49; 95% CI, 0.91-2.43; p = 0.11). Neither multivitamins nor vitamin A had an effect on HIV status at 6 weeks among those who were HIV-negative at birth (RR = 1.04; 95% CI, 0.65-1.66; p = 0.88) and (RR = 1.30; 95% CI, 0.80-2.09; p = .29, respectively). Similarly, neither supplement was associated with being either HIV-infected or dead at birth (RR, 0.98; 95% CI, 0.76-1.27; p = .89 and RR, 1.01; 95% CI, 0.78-1.31; p = .95, respectively. A beneficial effect of multivitamins on birth weight was limited to babies who were HIV-negative at birth; babies in the multivitamin arm weighed +94 g more compared with those in the no-multivitamin arm (p = .02). Among babies who were HIV-positive at birth, the corresponding difference was -31 g (p = .82). CONCLUSIONS: Vitamin A and multivitamins did not affect the risk of vertical transmission of HIV in utero nor during the intrapartum and early breastfeeding periods. Multivitamins resulted in a significant improvement in birth weight of babies who were HIV-negative at birth but had no effect among those who were HIV-positive. The effect of vitamin supplements on HIV transmission through breastfeeding and on clinical progression of HIV disease is yet to be ascertained.     

Farming, rural lifestyle and atopy in adults from southern Germany – results from the MONICA/KORA study Augsburg

BACKGROUND AND OBJECTIVE: The increasing urbanization and the decrease in the numbers of farms in southern Germany might be associated with an increasing prevalence of allergic diseases. We compared the prevalence of allergic diseases in farmers, and rural, suburban and urban residents in the small geographical area of Augsburg in southern Germany. METHODS: In a cross-sectional survey adults, aged 25-75 years selected from the community population register were investigated. Rural, suburban and urban residents were defined by community size and farmers by occupation. Allergic respiratory disorders were assessed by self-administered questionnaires and specific IgE antibodies to five common aeroallergens. RESULTS: In comparison to rural residents the urban population had an increased risk of allergic rhinitis (OR = 1.5; 95% CI: 1.2-1.9), atopic sensitization (OR = 1.2; 95% CI: 1.0-1.4) and sensitization against pollen (OR = 1.5; 95% CI: 1.2-1.9). There was no difference in the risk of asthma (OR = 1.0; 95% CI: 0.6-1.6) and a decreased risk in the sensitization against house dust mite (OR = 0.8; 95% CI: 0.7-1.0). The suburban residents did not differ from urban residents. Farmers had lower risks in allergic rhinitis, atopic sensitization, sensitization against pollen and mites (OR = 0.63; 0.86; 0.51 and 0.80, respectively) than rural non-farming residents, however, these differences were statistically not significant. Reported allergic rhinitis with sensitization to pollen was 2.5 times (95% CI: 1.8-3.6) more prevalent in urban than in rural residents. CONCLUSION: A farming environment and rural lifestyle might be associated with unknown protective factors impacting the prevalence of allergies.     

Allergic rhinitis and asthma comorbidity in a survey of young adults in Italy

BACKGROUND: Several studies have provided evidence of a strong association between asthma and allergic or nonallergic rhinitis, leading to the hypothesis that allergic rhinitis (AR) and asthma represent a continuum of the same disease. AIM: The aims of our study were: (i) to measure the comorbidity of AR and asthma and asthma-like symptoms and (ii) to assess whether asthma, AR, and their coexistence share a common pattern of individual risk factors. METHODS: The subjects are participants from the Italian multicentre, cross-sectional survey on respiratory symptoms in the young adult general population (Italian Study of Asthma in Young Adults, ISAYA). The relationship between individual risk factors and asthma, AR and their coexistence, was studied by means of a multinomial logistic regression. RESULTS: About 60% of asthmatics reported AR. On the other hand, subjects with AR presented an eightfold risk of having asthma compared to subjects without AR. Age was negatively associated with asthma [OR = 0.89, 95% confidence interval (CI): 0.82-0.96], AR (OR = 0.92, 95% CI: 0.86-0.98), and asthma associated with AR (OR = 0.83, 95% CI: 0.79-0.88). The risk of AR without asthma was significantly higher in the upper social classes (OR = 1.23, 95% CI: 1.08-1.39). Active current smoking exposure was positively associated with asthma alone (OR = 1.24, 95% CI: 1.09-1.41) and negatively associated with AR with (OR = 0.69, 95% CI: 0.54-0.88) or without (OR = 0.76, 95% CI: 0.69-0.84) asthma. CONCLUSIONS: Asthma and AR coexist in a substantial percentage of patients; bronchial asthma and AR, when associated, seem to share the same risk factors as AR alone while asthma without AR seems to be a different condition, at least with respect to some relevant risk factors.     

Inverse association between Mycobacterium tuberculosis infection and atopic rhinitis in children

BACKGROUND: The association between Mycobacterium tuberculosis (MTB) infection and atopy remains controversial. AIM: To investigate the association between MTB infection and atopic rhinitis in children living in a high TB incidence area. METHODS: In this cross-sectional study 418 children aged 6-14 years from an established epidemiological research-site in a poor urban community were invited to participate. They were assessed for allergic rhinitis (ISAAC questionnaire) and skin responses to tuberculin and eight environmental allergens. The presence of a BCG scar was documented, intestinal parasites and total and Ascaris lumbricoides-specific IgE levels were measured. Atopic rhinitis was defined, using the new World Allergy Organization (WAO) definition, as reported allergic rhinitis and a positive skin prick test (SPT > or =3 mm) to any allergen. RESULTS: Among the 337 children enrolled 10.4% had allergic rhinitis, 17.5% a positive SPT and 53% a positive tuberculin skin test (TST > or =10 mm). Children with a positive TST were significantly less likely to have recent atopic rhinitis (OR(adjusted) 0.06; 95% CI 0.007-0.5) than those with a negative TST. SPTs were significantly more common in children with negative TST who had recent allergic rhinitis (OR(adj) 34.0; 95% CI 7.6-152.6), but not in children with positive TST and recent allergic rhinitis (OR(adj) 0.6; 95% CI 0.07-5.2). CONCLUSIONS: MTB infection seems to reduce the prevalence of atopic rhinitis, and influences SPT reactivity in children with allergic rhinitis from a high TB incidence area.