Risk factors for ventilatory impairment among middle-aged and elderly men. The Normative Aging Study

Atopy in people aged 40 years and over: Relation to airflow limitation

BACKGROUND

Previous studies have reached conflicting conclusions about the role of atopy as a risk factor for COPD. In part, this is attributable to variation in the definitions of airflow limitation and the treatment of people with asthma.

OBJECTIVE

To establish whether there is any independent association between atopy and post-bronchodilator airflow limitation in the general population aged 40 years and over.

METHODS

A cross-sectional survey was conducted in a general population sample of 2415 people aged 40 years and over in Australia. A history of ever being diagnosed with asthma was elicited by questionnaire. Atopy was defined as any skin prick test weal to common aeroallergens ≥4 mm. Airflow limitation was defined as post-bronchodilator spirometric (FEV₁ /FVC) ratio <lower limit of normal. Analyses were adjusted for potential confounding due to age, sex, smoking, race and socio-economic status.

RESULTS

The prevalence of atopy, ever diagnosed asthma and post-bronchodilator airflow obstruction was 44.8%, 19.3% and 7.5%, respectively. In the population as a whole, atopy was associated with lower FEV₁ (adjusted difference -0.068L, 95% confidence interval (CI) -0.104 to -0.032), FVC (adj. difference -0.043L, 95% CI -0.086 to -0.0009) and post-bronchodilator FEV₁/FVC ratio (adj. difference -0.011, 95% CI -0.017 to -0.0055). The effect of atopy on lung function was no longer apparent when participants who reported ever diagnosed asthma were excluded (FEV₁ -0.011L, [95% CI -0.05 to 0.028L], FVC -0.012L [95% CI -0.060 to 0.036] and FEV₁/FVC ratio -0.0012 [95% CI -0.0072 to 0.0047L]).

CONCLUSION AND CLINICAL RELEVANCE

The apparent association between atopy and post-bronchodilator airflow limitation in the general population appears to be explained by the association between atopy and having ever diagnosed asthma and the effect of asthma on lung function.

Serum tocopherol levels and vitamin E intake are associated with lung function in the normative aging study

BACKGROUND & AIMS

The results of studies assessing relationships between vitamin E intake and status and lung function are conflicting. This study aimed to evaluate the effect of vitamin E intake and serum levels of tocopherol isoforms on lung function in a cross-sectional sample of 580 men from the Normative Aging Study, a longitudinal aging study.

METHODS

Regression models were used to look at associations of serum tocopherol isoform levels and vitamin E intake with lung function parameters after adjustment for confounders. Vitamin E intake was measured using a food frequency questionnaire and serum levels of γ, α, and δ-tocopherol levels were measured using high-performance liquid chromatography.

RESULTS

After adjustment for potential confounders, serum γ-tocopherol had a significant inverse association with forced vital capacity (β = -0.10, p = 0.05). Alpha and δ-tocopherol were not associated with any lung function parameter. After classifying COPD status according to Global Initiative for Obstructive Lung Disease (GOLD) stage criteria, serum levels of δ-tocopherol were lower in participants with more severe COPD (p = 0.01). Serum levels of δ-tocopherol were also lower in participants with greater levels of smoking (p = 0.02). Both vitamin E intake (β = 0.03, p = 0.02; β = 0.03, p = 0.01) and use of vitamin E supplements (β = 0.05, p = 0.03; β = 0.06. p = 0.02) were positively associated with FEV1 and FVC, after adjusting for confounders. Subjects who took vitamin E supplements had significantly higher α-tocopherol levels (p < 0.0001) and lower γ-tocopherol levels (p < 0.0001) than non-users.

CONCLUSION

In this study, there is a positive association between dietary vitamin E intake and lung function, and evidence of an inverse relationship between serum levels of γ-tocopherol and lung function.

Physiologic changes associated with violence and abuse exposure: an examination of related medical conditions

Although the extant evidence is replete with data supporting linkages between exposure to violence or abuse and the subsequent development of medical illnesses, the underlying mechanisms of these relationships are poorly defined and understood. Physiologic changes occurring in violence- or abuse-exposed individuals point to potentially common biological pathways connecting traumatic exposures with medical outcomes. Herein, the evidence describing the long-term physiologic changes in abuse- and violence-exposed populations and associated medical illnesses are reviewed. Current data support that (a) specific neurobiochemical changes are associated with exposure to violence and abuse; (b) several biological pathways have the potential to lead to the development of future illness; and (c) common physiologic mechanisms may moderate the severity, phenomenology, or clinical course of medical illnesses in individuals with histories of exposure to violence or abuse. Importantly, additional work is needed to advance our emerging understanding of the biological mechanisms connecting exposure to violence and abuse and negative health outcomes.

Association between lung function and cognition among children in a prospective birth cohort study

OBJECTIVES

To examine the relationship between lung function and cognition among children in the Maternal-Infant Smoking Study of East Boston, a prospective cohort of women and children enrolled before 20 weeks of gestation. A number of studies have demonstrated a relationship between lung function and cognition among adults, but this relationship has not been studied among children.

METHODS

At 6 years of age, children completed lung function tests. At 9 years of age, the Wide Range Assessment of Memory and Learning (WRAML) and Kaufman Brief Intelligence Test (K-BIT) were administered. Linear regression was used to assess the relationship between cognition and lung function.

RESULTS

The sample of 165 children included 53% girls and 52% Hispanic. Mean (+/- standard deviation) forced expiratory volume in 1 second (FEV (1)) was 1.26 +/- 0.2 L; mean forced vital capacity (FVC) was 1.37 +/- 0.2 L. In multivariate regression, a 1% increase from expected FEV(1) was associated with increases in the matrices and composite subscales of the K-BIT (p < .05), and in the verbal and learning subscales of the WRAML (p < .10). FVC was associated with increases in the composite and matrices subscale of the KBIT and in the visual and learning subscales of the WRAML (all p < .05).

CONCLUSION

Increased lung function was associated with increased cognitive development among children after adjusting for tobacco exposure, birthweight, and peak blood lead. Lung and cognitive function may operate under common regulatory processes and thus have shared vulnerabilities to a host of environmental factors during development.

Violence exposure, a chronic psychosocial stressor, and childhood lung function

OBJECTIVE

Chronic psychosocial stressors, including violence, and neuropsychological and behavioral development in children as well as physiologic alterations that may lead to broader health effects.

METHODS

We studied the relationship between violence and childhood lung function in a prospective birth cohort of 313 urban children (age range = 6-7 years). Mothers reported on their child's lifetime exposure to community violence (ETV) and interparental conflict in the home (Conflict Tactics Scale (CTS)) within 1 year of the lung function assessment.

RESULTS

In linear regression analyses, adjusting for maternal education, child's age, race, birthweight, tobacco smoke exposure, and medical history, girls in the highest CTS verbal aggression tertile had a 5.5% (95% confidence interval (CI) = -9.6, -1.5) decrease in percent predicted forced expiratory volume (FEV(1)) and a 5.4% (95% CI = -9.7, -1.1) decrease in forced vital capacity (FVC) compared with girls in the lowest tertile. The CTS verbal aggression subscale was associated with lung function among boys in the same direction, albeit this was not statistically significant. Boys in the highest ETV tertile had a 3.4% (95% CI = -8.0, 1.1) lower FEV(1) and 5.3% lower FVC (95% CI = -10.2, -0.4) compared with boys in the lowest tertile. The ETV score was not a significant predictor of girls' lung function.

CONCLUSIONS

Interparental conflict, specifically verbal aggression, and ETV were associated with decreased childhood lung function independent of socioeconomic status, tobacco smoke exposure, birthweight, and respiratory illness history. Gender differences were noted based on the type of violence exposure, which may warrant further exploration.

Inflammation and remodelling in the ageing airway

WHAT WE NEED TO KNOW: What changes occur in atopic and non-atopic airway inflammation in asthma with increasing age? What is the relationship between wound healing and airway remodelling in older subjects? What is the response to anti-inflammatory therapy in older subjects? What is the basis of the "overlap syndrome" with chronic obstructive pulmonary disease in older people with asthma, in whom smoking contributes to airway disease? WHAT WE NEED TO DO: Identify the contribution of immunological mechanisms to asthma in ageing. Determine the extent to which airway remodelling plays a role in airflow obstruction in older people, specifically reversible components. Reduce the impact of smoking in young people with asthma.

Risk factors for the development of chronic obstructive pulmonary disease

Cigarette smoking clearly has been shown to be the major environmental risk factor predisposing to the development of COPD. Occupational exposures to dust and fumes, air pollution, passive smoke exposure, childhood respiratory infections, and diet may also contribute. Airway hyperresponsiveness is a risk factor for the development of decline in FEV1, but its role in the development of COPD remains uncertain. Alpha1-antitrypsin deficiency is an important genetic risk factor for COPD in the small minority of COPD patients who inherit this deficiency. Other genetic factors are likely involved but have not yet been identified. Elucidation of additional genetic risk factors may provide useful insights into the pathogenesis of COPD. Potential interactions between the various environmental and genetic risk factors may be extremely important in determining the variable development of COPD.

Total serum IgE and FEV1 by respiratory symptoms and obstructive lung disease in adults of a Norwegian community

BACKGROUND

The importance of total serum IgE level on lung function impairment has not been established in a general population.

OBJECTIVE

The aim of this cross-sectional community study was to examine the relationship between total serum IgE and level of lung function in adults, and whether this relationship differed by sex, age, smoking habits or by respiratory symptoms and disease status.

METHODS

A stratified random sample of 18-73 year old adults from the general population were invited to spirometry and serum analyses of total and specific IgE. Of 1512 subjects invited, 82% met and performed complete examinations.

RESULTS

Increasing level of total serum IgE was related to reduced lung function (P < 0.01) given as sex, age, and height standardized residuals of one second forced expiratory volume (SFEV1). Subjects with total serum IgE in the highest vs the lowest tertile had a mean SFEV1 of -0.28, corresponding to age and height adjusted FEV1 differences of 120 and 150 mL in women and men, respectively. The relationship between IgE and lung function impairment did not differ significantly by sex, age or smoking habits. In subjects with obstructive lung disease increasing level of total serum IgE was more negatively associated with lung function level than in subjects with respiratory symptoms alone. No relationship was observed in asymptomatic subjects. This was confirmed in a multiple linear regression analysis adjusting for sex, age, smoking habits and lifetime smoking consumption showing that SFEV1 was predicted by an interaction between total serum IgE level and symptom and disease status (P < 0.01). This interaction remained after excluding subjects (n = 105) having specific IgE antibodies.

CONCLUSION

Increasing total serum IgE level was associated with progressively lower lung function in a general adult population after taking other predictors of impaired spirometric lung function into account, though dependent on the subjects' respiratory symptom and disease status. Variation in prevalences of respiratory symptoms and obstructive lung disease in previous examined populations may thus explain conflicting observations of the association between total IgE and airflow impairment.