Biomedical subjects

Stefano Guerra

Publications and source records attributed to Stefano Guerra.

18 recordsLinked to original sources

PubMed2005

Outcome of asthma and wheezing in the first 6 years of life: follow-up through adolescence.

RATIONALE: The effect of early life wheezing on respiratory function and continued symptoms through adolescence has not been fully described. Using data from a population-based birth cohort in Tucson, Arizona, we previously described four phenotypes based on the occurrence of wheezing lower respiratory illnesses before age 3 yr and active wheeze at age 6 yr: never wheezers (n = 425), transient early wheezers (n = 164), persistent wheezers (n = 113), and late-onset wheezers (n = 124). OBJECTIVE: We sought to determine the prognosis for these phenotypes, with reference to lung function and symptoms, through adolescence. METHODS: Current wheeze was assessed by questionnaire, lung function was measured by conventional spirometry, and atopy was determined by skin prick tests. RESULTS: The prevalence of atopy and wheeze by age 16 yr was similar for never and transient wheezers and for persistent and late-onset wheezers. Both transient early, and persistent wheezers had significantly lower FEF(25-75) (-259 ml/s, p < 0.001, and -260 ml/s, p = 0.001, respectively), FEV1 (-75 ml, p = 0.02, and -87 ml, p = 0.03, respectively), and FEV1:FVC ratio (-1.9%, p = 0.002, and -2.5%, p = 0.001, respectively) through age 16 yr compared with never wheezers. Late-onset wheezers had levels of lung function similar to those of never wheezers through age 16 yr. There was no significant change in lung function among subjects with any of the four phenotypes, relative to their peers, from age 6 to 16 yr. CONCLUSION: Patterns of wheezing prevalence and levels of lung function are established by age 6 yr and do not appear to change significantly by age 16 yr in children who start having asthma-like symptoms during the preschool years.

Adolescent↗

PubMed2005

Obstructive sleep apnea and ischemic heart disease in southwestern US veterans: implications for clinical practice.

This study describes associations between obstructive sleep apnea (OSA), intake of food rich in antioxidant nutrients, and ischemic heart disease (IHD) in military veterans. Subjects were male veterans (n=211), 54 to 85 years of age, and enrolled in primary care clinics at the Southern Arizona Veterans Affairs Health Care System (SAVAHCS), Tucson, AZ. Measures included the SAVAHCS Minority Vascular Center Questionnaire, the Sleep Heart Health Study Sleep Habits Questionnaire, the Arizona Food Frequency Questionnaire, height, weight, and blood pressure. Veterans with OSA were significantly more likely to be obese, to have elevated systolic blood pressure and physician-diagnosed IHD, more likely to undergo coronary angiography, and less likely to consume foods rich in cardioprotective antioxidants compared to veterans without OSA. After adjusting for confounding variables, the association between OSA and IHD remains significant [adjusted OR=2.99, confidence interval (CI)=1.07-8.42]. These data reinforce the importance of recognizing OSA within the veterans affairs health care system and suggest that early detection of OSA may improve veterans' health and well-being and reduce associated medical costs.

Aged↗

PubMed2005

Association of atopy and eczema with polymorphisms in T-cell immunoglobulin domain and mucin domain-IL-2-inducible T-cell kinase gene cluster in chromosome 5 q 33.

BACKGROUND: The T-cell immunoglobulin domain and mucin domain (TIM) gene family and the gene for IL-2-inducible T-cell kinase (ITK), located in chromosome 5 q 33 and potentially involved in the T-cell proliferation and differentiation, are good candidate genes for allergic diseases. OBJECTIVE: We assessed the role of polymorphisms in the TIM family genes and ITK in atopy, eczema, and asthma. METHODS: Twenty-one polymorphisms in the TIM-ITK gene cluster were genotyped in 564 children enrolled in the Tucson Children's Respiratory Study. Skin prick tests to common allergens were performed at age 6.1 years (n=508), age 10.8 years (n=539), and age 16.6 years (n=424). Asthma and eczema were assessed by questionnaire at these 3 points. Averaged relative risks were estimated. RESULTS: One 15-bp insertion/deletion in exon 4 of TIM 1 was significantly related to atopy and eczema (relative risk associated with carrying at least 1 rare allele=1.24 [1.07--1.45], P=.005; and 1.43 [1.01--2.01], P=.004, respectively). The 3 tested single nucleotide polymorphisms (SNPs) in TIM 3 were significantly related to atopy and eczema. One of them, at position +4259 calculated from the translation start site, predicts a putative change in the amino acid sequence of the protein, and was the most strongly related to atopy (relative risk=1.28 [1.12--1.47]; P=.0003). SNPs in the 5' genomic region in ITK, which show moderate linkage disequilibrium with those in TIM 3, had an independent effect on atopy. None of the polymorphisms studied was related to asthma. CONCLUSION: Our findings support a potential role for SNPs in TIM 1, TIM 3, and ITK, independent of each other, in allergic diseases.

Adolescent↗

PubMed2005

The relation of rhinitis to recurrent cough and wheezing: a longitudinal study.

BACKGROUND: Recurrent cough can be a clinical manifestation of rhinitis. However, it remains unclear if the association between rhinitis and recurrent cough among children is independent of asthma. OBJECTIVE: The aim of the present study was to determine, in a large longitudinal cohort, whether rhinitis is significantly associated with recurrent cough alone, wheezing alone, or the combination of both symptoms during childhood. METHODS: We investigated determinants of recurrent cough, with or without wheezing, using longitudinal data from the Tucson Children's Respiratory Study. Among the 1246 subjects originally enrolled, 1024 children completed at least one questionnaire between the ages of 6 and 18 years and were included in the present study. In any survey, wheezing was defined as at least one wheezing episode during the past year and recurrent cough as two or more coughing episodes lasting at least 1 week without a cold during the past year. Generalized estimating equations were used to determine significant risk factors. RESULTS: After adjusting for sex, skin test reactivity and parental asthma, both rhinitis (OR = 2.47 CI = 1.84, 3.30) and sinusitis (OR = 1.54 CI = 1.11, 2.14) were associated with an increased risk of recurrent cough plus wheezing. The OR associated with rhinitis were significantly reduced for subjects reporting only recurrent cough or only wheezing (OR = 1.43, CI = 1.03, 1.99; and OR = 1.30, CI = 1.07, 1.58, respectively). Recurrent cough and wheezing, when examined independently, showed different patterns of risk factors. CONCLUSION: We found rhinitis to be an independent risk factor for both recurrent cough and wheezing during childhood. Different pathways may be involved in the association of rhinitis with recurrent cough and wheezing.

Adolescent↗

PubMed2005

Overlap of asthma and chronic obstructive pulmonary disease.

PURPOSE OF REVIEW: Asthma and chronic obstructive pulmonary disease (COPD) are both defined by the presence of airflow obstruction, but they present distinguishing differences in terms of both risk factors and clinical phenotypes. Yet it is quite common in the clinical setting to observe patients with asthma showing COPD-like phenotypes, and vice versa, making it a priority to search for optimal prevention, treatment, and management strategies for these cases of coexisting lung obstructive diseases. RECENT FINDINGS: Recent studies have provided further evidence of strong epidemiologic and clinical links between asthma and COPD. Adult subjects with active asthma are as much as 12 times more likely to acquire COPD over time than subjects with no active asthma. Signs identifying patients with asthma predisposed to developing COPD may already be present at the early stages of the disease, a finding with potential implications for prevention of COPD. In addition to spirometry and other pulmonary function tests (such as measurements of residual volume and diffusing capacity of the lung for carbon monoxide), recent evidence suggests that the assessment of type and degree of airway remodeling and the evaluation of inflammatory markers might prove useful in the future to characterize phenotypically patients with coexisting asthma and COPD. SUMMARY: The nature of the association between asthma and COPD remains unclear and open to discussion. Further research is required to develop effective management algorithms for patients with multiple obstructive lung diseases, determine to what extent early treatment and optimal management of asthma may protect against progression into COPD, and identify genetic markers of individual susceptibility to specific lung disease phenotypes and pharmacologic treatments.

Asthma↗

PubMed2005

Relation of beta2-adrenoceptor polymorphisms at codons 16 and 27 to persistence of asthma symptoms after the onset of puberty.

BACKGROUND: It has long been recognized that many children with asthma outgrow the disease after the onset of puberty, but little is known about genetic factors influencing this outcome. OBJECTIVES: The aim of the present study was to determine whether the polymorphisms at codons 16 and 27 of the beta2-adrenoceptor are significant predictors of the persistence of asthma during adolescence. DESIGN AND PARTICIPANTS: We used data from the prospective Tucson Children's Respiratory Study. Children were genotyped for the polymorphisms at codons 16 and 27. The presence of wheezing/asthma was assessed by questionnaire from age 6 years up to the reported onset of puberty (prepubertal period) and after the onset of puberty up to age 16 years (adolescence). RESULTS: Among children who wheezed in the prepubertal period (n = 168), subjects homozygous for Gly at codon 16 were at significantly increased risk for persistent wheezing after puberty, as compared with carriers of the other genotypes (relative risk [RR], 1.43; 95% confidence interval [CI], 1.06 to 1.92; p = 0.019). This relation was present among boys (RR, 2.17; 95% CI, 1.41 to 3.36) but not girls (RR, 0.85; 95% CI, 0.55 to 1.30), and increased linearly according to the frequency of wheezing episodes after the onset of puberty. These findings persisted after adjusting for ethnicity and other potential confounders and after selecting only white children. The polymorphism at codon 27 showed no relation with risk for persistent wheezing. CONCLUSIONS: This study provides evidence for a strong gender-specific effect of the Gly16 polymorphism on the persistence of asthma after the onset of puberty.

Adolescent↗

PubMed2004

Persistence of asthma symptoms during adolescence: role of obesity and age at the onset of puberty.

Little is known about rates and predictors of remission of childhood asthma after the onset of puberty. We used data collected at ages 6, 8, 11, 13, and 16 years from the Tucson Children's Respiratory Study, a population-based birth cohort. The onset of puberty was defined as the age of appearance of the first pubertal signs as reported by parents. Information on wheezing both before and after onset of puberty (mean +/- SD follow-up from onset of puberty, 4.2 +/- 1 year) was available for 781 children. Of these, 166 had asthma (either frequent wheezing or a physician-confirmed diagnosis plus any wheezing) in at least one survey before puberty. In this group, 58% of the children (97 of 166) reported the presence of wheezing after the onset of puberty (unremitting asthma). In contrast, only 30% (39 of 131) of the children with infrequent wheezing before puberty experienced wheezing episodes after the onset of puberty (unremitting wheezing). In addition to frequent wheezing before puberty, obesity, early onset of puberty, active sinusitis, and skin test sensitization were significant and independent predictors of unremitting asthma after the onset of puberty. Our findings from a population-based longitudinal cohort challenge the commonly held view that asthma usually remits during adolescence.

Adolescent↗

PubMed2004

Parental asthma as a risk factor for the development of early skin test sensitization in children.

BACKGROUND: Recent epidemiologic evidence has challenged the paradigm suggesting a direct causal relationship between allergic sensitization and asthma. OBJECTIVE: We sought to investigate the role of a familial predisposition for asthma in the development of atopy in children. METHODS: Subjects were participants in the Tucson Children's Respiratory Study. Skin tests to aeroallergens were performed in parents and in children at ages 6, 11, and 16 years. Parents were considered asthmatic if they reported physician-confirmed asthma. Parents were divided into 4 phenotypes on the basis of skin sensitization (Skt+ or Skt-) and asthma status (As+ or As-): Skt-/As-, Skt-/As+, Skt+/As-, and Skt+/As+. RESULTS: Children's allergic sensitization differed among parental phenotypes at all ages (P <.0001). Children in the Skt+/As- and Skt+/As+ groups were significantly more likely to be allergic than children in the Skt-/As- group at all ages. Among children with allergic parents, those with at least one parent with asthma were significantly more likely to have positive skin test responses than those with nonasthmatic parents at age 6 years (52.4% vs 37.4%, P <.005) and 11 years (70.1% vs 55.6%, P <.005) but not at age 16 years (82.3% vs 75.1%, P =.180). Results were independent of wheezing in the child and of the characteristics of atopy in parents. The Skt-/As+ group had too few subjects for meaningful comparisons. CONCLUSION: Among children of atopic parents, parental asthma is a risk factor for allergic sensitization in early childhood. The strong association between allergic sensitization and asthma is at least in part explained by an increased susceptibility to allergen sensitization in subjects predisposed to asthma.

Adolescent↗

PubMed2004

Associations between chemical odor intolerance and sleep disturbances in community-living adults.

OBJECTIVE: To investigate associations between sleep disturbances and chemical odor intolerance (COI), which is the subjective report of feeling ill from common odors, such as carpet glue or pesticides. METHODS: This cross-sectional study consisted of government employees and their family members (n=140; 61% women, mean age=46.3 years) derived from a stratified cluster population living in Pima County, Tucson, AZ. Subjects completed a standard survey that included sleep symptoms, a validated measure of COI, and two questions regarding anxiety and depression. Odds ratios (OR) with 95% confidence intervals (CI) were computed to test the association between COI and sleep symptoms. Stratification according to the Mantel-Haenszel method and logistic regression models were used to test for confounding and/or effect modification. RESULTS: After adjusting for age and gender, subjects with COI were significantly more likely to report difficulty staying asleep (OR=3.06; CI=1.17-8.03), insufficient sleep (OR=3.93; CI=1.43-10.79), and nightmares (OR=3.17; CI=1.14-8.81) compared to persons without COI. Associations between COI, sleep maintenance problems and insufficient sleep were still significant after adjusting for gender and depression; however, the association between COI and nightmares became borderline. CONCLUSIONS: Compared to the non-COI, persons with COI are more likely to report sleep maintenance insomnia and insufficient sleep independent of self-reported depression. Nightmares appear to be related more to depression than to COI.

Adhesives↗

PubMed2004

The differential effect of genetic variation on soluble CD14 levels in human plasma and milk.

PROBLEM: The protein CD14 is a pattern recognition receptor for bacterial lipopolysaccharide (LPS). Whether genetic variation has the same influence on soluble CD14 (sCD14) levels in human plasma and milk remains to be determined. METHOD OF STUDY: We measured sCD14 levels in plasma during pregnancy (n = 196) and in milk in the postpartum (n = 152) for women genotyped for the single nucleotide polymorphisms (SNPs) at positions -1619, -550, and -159 from the transcription start site of the CD14 gene. RESULTS: Plasma- and milk-sCD14 levels differed significantly both by CD14/-1619 and CD14/-550 genotypes and by haplotypes. Most interestingly, sCD14 levels were regulated differentially by the same genetic variants in plasma and milk, with the CD14/-550T allele and the corresponding are ATC haplotype associated with high sCD14 in milk but low sCD14 in plasma. A correlation between sCD14 levels in plasma and milk was absent (r = 0.091, P = NS). CONCLUSIONS: Our findings suggest the existence of cell-specific regulation mechanisms of CD14 gene expression.

Adult↗

PubMed2004

Asthma as a risk factor for COPD in a longitudinal study.

BACKGROUND: For several years, asthma and COPD have been regarded as distinct entities, with distinct clinical courses. However, despite distinctive physiologic features at the time of diagnosis, and different risk factors, the two diseases over time may develop features that are quite similar. STUDY OBJECTIVE: To evaluate the association between physician-diagnosed asthma and the subsequent development of COPD in a cohort of 3,099 adult subjects from Tucson, AZ. DESIGN AND METHODS: A prospective observational study. Participants completed up to 12 standard respiratory questionnaires and 11 spirometry lung function measurements over a period of 20 years. Survival curves (with time to development of COPD as the dependent variable) were compared between subjects with asthma and subjects without asthma at the initial survey. RESULTS: Subjects with active asthma (n = 192) had significantly higher hazard ratios than inactive (n = 156) or nonasthmatic subjects (n = 2751) for acquiring COPD. As compared with nonasthmatics, active asthmatics had a 10-times-higher risk for acquiring symptoms of chronic bronchitis (95% confidence interval [CI], 4.94 to 20.25), 17-times-higher risk of receiving a diagnosis of emphysema (95% CI, 8.31 to 34.83), and 12.5-times-higher risk of fulfilling COPD criteria (95% CI, 6.84 to 22.84), even after adjusting for smoking history and other potential confounders. CONCLUSIONS: Physician-diagnosed asthma is significantly associated with an increased risk for CB, emphysema, and COPD.

Adult↗

PubMed2003

Reduced interferon gamma production and soluble CD14 levels in early life predict recurrent wheezing by 1 year of age.

It is unknown whether reduced production of IFNgamma in early life, before any lower respiratory tract illness, is a risk factor for recurrent wheezing in infancy. We followed 238 infants prospectively from birth to 1 year of age. At birth and at 3 months of age, IFNgamma production from polyclonally stimulated peripheral blood mononuclear cells and soluble CD14 (sCD14) levels in plasma were measured. The odds of developing recurrent wheezing (assessed by questionnaire) in the first year of life were up to 4.5 times higher for children in the lowest quartile of IFNgamma production at 3 months (p = 0.0005) and 3.2 times higher for children in the lowest quartile of sCD14 levels at birth (p = 0.004) as compared with children in the other 3 combined quartiles of IFNgamma and sCD14, respectively. Findings were confirmed in the multivariate analysis. IFNgamma production at 3 months and sCD14 levels at birth were correlated (r = 0.188, p = 0.031). Our findings from a longitudinal cohort suggest that impaired IFNgamma production at 3 months and reduced plasma-sCD14 levels at birth significantly increase the risk of developing recurrent wheezing in the first year of life.

Age Factors↗

PubMed2003

TGF-beta in human milk is associated with wheeze in infancy.

BACKGROUND: Cytokines secreted in human milk might play important roles in newborn health and in the development of infant immune responses. We investigated the relationship of the concentration and dose of cytokines in human milk to infant wheeze at 1 year of age. OBJECTIVE: Our objective was to test whether the cytokines in milk could account for some of the apparent protective effect of breast-feeding against wheeze in the first year of life. METHODS: Data on breast-feeding and infant wheeze were collected prospectively from birth to 1 year from 243 mothers participating in the Infant Immune Study in Tucson, Arizona. Breast milk samples obtained at a mean age of 11 days postpartum were assayed by means of ELISA for concentrations of TGF-beta1, IL-10, TNF-alpha, and the soluble form of CD14. The dose of each cytokine was assessed for a relationship with wheeze in bivariate and logistic regression analyses. RESULTS: Increasing duration of breast-feeding was significantly associated with a decreased prevalence of wheeze (P =.039). There was wide variability in levels of each cytokine in milk, as well as variability between women in the amount of each cytokine produced. There was a significant inverse association between the dose of TGF-beta1 received through milk with the percentage of wheeze (P =.017), and the relationship was linear (P =.006). None of the other cytokines showed a linear relationship with wheeze. In multivariate analyses the risk of wheeze was significantly decreased (odds ratio, 0.22; 95% CI 0.05-0.89; P =.034) with increasing TGF-beta1 dose (long breast-feeding and medium-high TGF-beta1 level compared with short breast-feeding and low TGF-beta. CONCLUSION: This analysis shows that the dose of TGF-beta1 received from milk has a significant relationship with infant wheeze, which might account for at least some of the protective effect of breast-feeding against wheeze.

Breast Feeding↗

PubMed2003

A longitudinal study of alpha1-antitrypsin phenotypes and decline in FEV1 in a community population.

BACKGROUND: It is well-known that the homozygous deficiency of alpha(1)-antitrypsin, phenotype PiZZ, is associated with an increased risk of COPD. However, studies evaluating the association between the heterozygous forms of the alpha(1)-antitrypsin phenotype PiMZ and rapid decline in lung function, both in patient and community populations, have yielded conflicting results. STUDY OBJECTIVE: To assess the relationship between alpha(1)-antitrypsin phenotypes and decline in FEV(1) values of 2,016 adult subjects in a community population in Tucson, AZ. DESIGN AND METHODS: Prospective cohort study. Standardized questionnaires and lung function measurements were administered 1.5 to 2 years apart during 12 surveys. RESULTS: The frequency distribution for PiMM, PiMS, and PiMZ phenotypes did not differ significantly by physician-confirmed diagnoses of emphysema, chronic bronchitis, or asthma. There was no statistically significant difference in mean FEV(1) slope values between PiMM, PiMS, and PiMZ phenotypes (-22.5, -21, and -7 mL per year, respectively). After controlling for smoking and other potential confounders, the FEV(1) slope was associated with an initial FEV(1) level and age for the initial questionnaire but not with the different phenotypes. Selecting cutoff values, we identified rapidly declining and nondeclining subgroups, based on the percent predicted changes in FEV(1). They also were not associated with alpha(1)-antitrypsin phenotypes. CONCLUSIONS: We conclude that the data from this longitudinal community study suggest that having the PiMZ phenotype is not a significant risk factor for an accelerated decline in FEV(1).

Adult↗

PubMed2002

Rhinitis as an independent risk factor for adult-onset asthma.

BACKGROUND: For many years, the association between asthma and rhinitis has primarily been attributed to a common allergic background. Recently, it has been suggested that asthma and rhinitis are associated in the absence of atopy. The nature of this association is not well known. OBJECTIVE: The purpose of this study, which was performed in a large, longitudinal community population, was to determine the extent to which rhinitis is an independent risk factor for adult-onset asthma. METHODS: We carried out a nested case-control study from the longitudinal cohort of the Tucson Epidemiologic Study of Obstructive Lung Diseases. One hundred seventy-three incident patients with physician-confirmed asthma were compared with 2177 subjects who reported no asthma or shortness of breath with wheezing. Potential risk factors, including the presence of rhinitis, were assessed before the onset of asthma (patients) or before the last completed survey (control subjects). RESULTS: Rhinitis was a significant risk factor for asthma (crude odds ratio, 4.13; 95% confidence interval, 2.88-5.92). After adjustment for years of follow-up, age, sex, atopic status, smoking status, and presence of chronic obstructive pulmonary disease, the magnitude of the association was reduced but still highly significant (adjusted odds ratio, 3.21; 95% confidence interval, 2.19-4.71). After stratification, rhinitis increased the risk of development of asthma by about 3 times both among atopic and nonatopic patients and by more than 5 times among patients in the highest IgE tertile. Patients with rhinitis with persistent and severe nasal symptoms and a personal history of physician-confirmed sinusitis had an additional increased risk of asthma development. CONCLUSION: We conclude that rhinitis is a significant risk factor for adult-onset asthma in both atopic and nonatopic subjects. The nature of the association between rhinitis and asthma is open to interpretation.

Adult↗

PubMed2002

How accurate is the self-reported diagnosis of chronic bronchitis?

BACKGROUND: Although it is defined as cough and sputum production for at least 3 months per year for at least 2 consecutive years, difficulties exist in the use of the term chronic bronchitis for clinical diagnosis. In particular, the relationship between diagnosis and symptoms has been difficult to ascertain. STUDY OBJECTIVES: To determine, in a large epidemiologic study, the degree to which a new self-reported diagnosis of chronic bronchitis (NCBR) satisfies the symptom criteria for that diagnosis, and to determine the relationship between self-reported physician-confirmed diagnoses and symptom criteria. METHODS: We analyzed data obtained from the Tucson Epidemiologic Study of Obstructive Lung Diseases. Using responses to standardized respiratory questionnaires administered to 4,034 subjects, those with NCBRs were selected and assessed as to whether they met symptom criteria for that diagnosis. Descriptive statistics pertaining to gender, age, and smoking status were obtained. Furthermore, we determined how often symptom criteria were met among a subset of subjects with physician-confirmed self-reported diagnoses. RESULTS: Of 481 subjects with NCBRs, only 56 subjects (11.6%) met the required symptom criteria. Men compared with women and current smokers compared with ex-smokers or neversmokers were more likely to meet symptom criteria. Four hundred fifteen of 481 subjects with NCBRs had physician-confirmed self-reported diagnoses. Of these, only 52 subjects (12.5%) met symptom criteria. Within the subgroup of subjects who met symptom criteria, higher percentages were observed in the older age groups, but this was not statistically significant. CONCLUSION: Only a minority of subjects with NCBRs satisfy the symptom criteria of cough and sputum production for at least 3 months per year for at least 2 consecutive years. This relationship holds true even among those with physician-confirmed self-reported diagnoses.

Adolescent↗

PubMed2002

The relation of body mass index to asthma, chronic bronchitis, and emphysema.

BACKGROUND: Recent studies have suggested a relationship between asthma and obesity. Despite these reports, the effect of being underweight or overweight as a risk factor for airway obstructive diseases (AODs) is not clear. OBJECTIVES: To determine whether a relation of body mass index (BMI) to asthma, chronic bronchitis (CB), or emphysema exists (analysis 1), and, if so, whether the association between obesity and asthma is modified by gender (analysis 2). DESIGN: Nested case-control study from the longitudinal cohort of the Tucson Epidemiologic Study of Airways Obstructive Diseases. PATIENTS: Analysis 1: physician-confirmed incident cases of asthma (n = 102), CB (n = 299), or emphysema (n = 72) who denied any prior AODs. Analysis 2: all 169 incident cases of asthma, regardless of any previous AODs, stratified by gender and by other potential effect modifiers. In both analyses, we selected only subjects at least 20 years old who had weight and height measured during the study. MEASUREMENTS: BMI and other risk factors were assessed prior to the onset of the AOD (cases) or prior to the last completed survey (control subjects). RESULTS: A diagnosis of emphysema was significantly associated with a BMI < 18.5 (odds ratio [OR], 2.97; 95% confidence interval [CI], 1.33 to 6.68, when compared to healthy control subjects). A BMI >/= 28 increased the risk of receiving a diagnosis of asthma (OR, 2.10; 95% CI, 1.31 to 3.36) and CB (OR, 1.80; 95% CI, 1.32 to 2.46). About 30% of the patients with asthma and 25% of the patients with CB (vs 16% of the control subjects, p < 0.001) were preobese or obese, regardless whether BMI was assessed before the diagnosis or before the onset of respiratory symptoms. The relation of elevated BMI to asthma was significant only among women. CONCLUSIONS: Patients with emphysema are more likely to be underweight, and patients with CB are more likely to be obese. However, the temporal relationship between abnormal BMI and the onset of COPD is uncertain. Preobese and obese women are at increased risk of acquiring asthma. This relation, particularly if it is causal, has potentially relevant public health implications.

Adult↗

PubMedDate not supplied

On the association between date of birth and pollen sensitization: is age an effect modifier?

An association between date of birth and development of allergy has been proposed by prior research. Yet, the presence of a dose-response relationship or any potential effect modification for this association has not been widely studied. The aims of our study were to investigate whether an association between birth during pollen season and symptomatic sensitization to pollens exists, whether this association is stronger for patients with high rather than low allergic reactivity to pollens, and whether this association is modified by the age of the patients. Among 3318 asthmatic and/or rhinitic outpatients, we selected 805 patients sensitized exclusively to pollens (78 with low reactivity [LR] and 727 with high reactivity [HR]) and 629 patients with negative skin-prick tests (SPT) (control group). The association between being born during pollen season (February-July) and each of the pollen reactivity levels was assessed by estimating the odds ratios (OR). HR pollinosis patients were more likely than SPT negative patients of being born in February-July (OR 1.38, 95% Confidence Intervals (CI) 1.11-1.71). The likelihood of having been born in pollen season significantly increased across the levels of reactivity to pollens (HR > LR > SPT negative). These findings were valid only among patients with an early onset of symptoms. Although the OR for being born in pollen season was 1.91 (95% CI 1.32-2.77) for HR pollinosis patients with onset of symptoms < or = 15 years, it was 1.13 (95% CI 0.87-1.48) for those with later onset of symptoms (test of homogeneity: p = 0.026). Our results suggest that the exposure to allergenic pollens in the first months of life increases the risk of developing clinically relevant sensitization to them, particularly in the first 15 years of life.

Adolescent↗