Trust in scientific information mediates associations between conservatism and coronavirus responses in the U.S., but few other nations.

U.S.-based research suggests conservatism is linked with less concern about contracting coronavirus and less preventative behaviors to avoid infection. Here, we investigate whether these tendencies are partly attributable to distrust in scientific information, and evaluate whether they generalize outside the U.S., using public data and recruited representative samples across three studies (Ntotal = 34,710). In Studies 1 and 2, we examine these relationships in the U.S., yielding converging evidence for a sequential indirect effect of conservatism on compliance through scientific (dis)trust and infection concern. In Study 3, we compare these relationships across 19 distinct countries. Although the relationships between trust in scientific information about the coronavirus, concern about coronavirus infection, and compliance are consistent cross-nationally, the relationships between conservatism and trust in scientific information are not. These relationships are strongest in North America. Consequently, the indirect effects observed in Studies 1-2 only replicate in North America (the U.S. and Canada) and in Indonesia. Study 3 also found parallel direct and indirect effects on support for lockdown restrictions. These associations suggest not only that relationships between conservatism and compliance are not universal, but localized to particular countries where conservatism is more strongly related to trust in scientific information about the coronavirus pandemic.

Prospective audit of cross-sectional imaging and radiation exposure in general surgical patients.

INTRODUCTION: Most patients admitted with an acute surgical problem undergo some imaging during their in-patient stay. As computed tomography (CT) scanning becomes more readily available, it is becoming the mainstay of assessment. Recent studies have commented on the potential adverse effects of early cross-sectional imaging. This audit aimed to determine the use of early cross-sectional imaging and associated radiation dose in an acute surgical cohort. PATIENTS AND METHODS: Data from 500 acute surgical patients were prospectively collected over a 3-month period. CT scans were undertaken, the effect on subsequent diagnostic and management decisions and the potential associated risks were evaluated. RESULTS: Almost 40% of subjects underwent CT scanning. Of these, 20% did not alter management and could be deemed unnecessary. The radiation exposure equated to an age- and gender-specific risk of fatal cancer induction between 1 in 1675 and 1 in 7130. CONCLUSIONS: Early-cross sectional imaging provides a valuable diagnostic adjunct. Decisions to expose patients to potentially hazardous radiation need to acknowledge the anticipated benefits versus risks.

Prefrontal and hippocampal contributions to visual associative recognition: interactions between cognitive control and episodic retrieval.

The ability to recover episodic associations is thought to depend on medial-temporal lobe mnemonic mechanisms and frontal lobe cognitive control processes. The present study examined the neural circuitry underlying non-verbal associative retrieval, and considered the consequences of successful retrieval on cognitive control demands. Event-related fMRI data were acquired while subjects retrieved strongly or weakly associated pairs of novel visual patterns in a two-alternative forced choice associative recognition paradigm. Behaviorally, successful retrieval of strongly associated relative to weakly associated pairs was more likely to be accompanied by conscious recollection of the pair's prior co-occurrence. At the neural level, right ventrolateral prefrontal cortex (VLPFC) and hippocampus were more active during successful retrieval of Strong than of Weak associations, consistent with a role in visual associative recollection. By contrast, Weak trials elicited greater activation in right anterior cingulate cortex (ACC), which may detect conflict between the similarly familiar target and foil stimuli in the absence of recollection. Consistent with this interpretation, stronger ACC activity was associated with weaker hippocampal and stronger right dorsolateral PFC (DLPFC) responses. Thus, recollection of relevant visual associations (hippocampus and VLPFC) results in lower levels of mnemonic conflict (ACC) and decreased familiarity-based monitoring demands (DLPFC). These findings highlight the interplay between cognitive control and episodic retrieval.

Effects of testosterone and progressive resistance training in eugonadal men with AIDS wasting. A randomized, controlled trial.

BACKGROUND: Substantial loss of muscle mass occurs among men with AIDS wasting. OBJECTIVE: To investigate the independent effects of testosterone therapy and progressive resistance training in eugonadal men with AIDS wasting. DESIGN: Randomized, controlled trial. SETTING: University hospital. PATIENTS: 54 eugonadal men with AIDS wasting (weight < 90% ideal body weight or weight loss > 10%). INTERVENTION: In a 2 x 2 factorial design, patients were assigned to receive testosterone enanthate (200 mg/wk) or placebo injections and progressive resistance training (three times weekly) or no training for 12 weeks. MEASUREMENTS: Cross-sectional muscle area and other indices of muscle mass. RESULTS: Cross-sectional muscle area increased in response to training compared with nontraining (change in arm muscle mass, 499 +/- 349 mm2 vs. 206 +/- 264 mm2 [P = 0.004]; change in leg muscle mass, 1106 +/- 854 mm2 vs. 523 +/- 872 mm2 [P = 0.045]) and in response to testosterone therapy compared with placebo (change in arm muscle mass, 512 +/- 371 mm2 vs. 194 +/- 215 mm2 [P< 0.001]; change in leg muscle mass, 1,236 +/- 881 mm2 vs. 399 +/- 729 mm2 [P = 0.002]). Levels of high-density lipoprotein cholesterol decreased in response to testosterone therapy compared with placebo (-0.03 +/- 0.13 mmol/L vs. 0.05 +/- 0.13 mmol/L [-1 +/- 5 mg/dL vs. 2 +/- 5 mg/dL]; P= 0.011) and increased in response to training compared with nontraining (0.05 +/- 0.13 mmol/L vs. 0.00 +/- 0.16 mmol/L [2 +/- 5 mg/dL vs. 0 +/- 6 mg/dL]; P = 0.052). CONCLUSIONS: In contrast to anabolic therapies that may have adverse effects on metabolic variables, supervised exercise effectively increases muscle mass and is associated with significant positive health benefits in eugonadal men with AIDS wasting.

Comparison of total body potassium with other techniques for measuring lean body mass in men and women with AIDS wasting.

BACKGROUND: Lean body mass is an important predictor of survival and functional status in patients with AIDS wasting. The bias between different techniques for assessing body composition in AIDS wasting is not known. DESIGN: We compared total body potassium (TBK) with fat-free mass (FFM) determined by dual-energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA), and skinfold-thickness measurement (SKF) in 132 patients (63 men, 69 women) with AIDS wasting (weight < 90% of ideal body weight, or weight loss > 10% of original, or both). None of the subjects exhibited clinical lipodystrophy. Comparisons were made by using different BIA equations. RESULTS: Lean body mass determined by DXA was highly correlated with TBK in men (r = 0.79, P: < 0.0001) and women (r = 0.84, P: < 0.0001). FFM(BIA) and FFM(DXA) were significantly different (P: < 0.01 in men and P: < 0.0001 in women). The difference between FFM(DXA) and FFM(BIA) was significantly greater with greater weight and body fat, particularly in HIV-infected women (r = -0.39, P: = 0.001 for weight; r = -0.60, P: < 0.0001 for fat). The comparability of FFM and fat mass determined by DXA and BIA was dependent on the specific BIA equation used. Among men, no single BIA equation was more highly predictive of fat mass and FFM in comparison with DXA. CONCLUSIONS: The differences between DXA, BIA, and SKF in the determination of fat mass and FFM are significant in patients with AIDS wasting. BIA overestimates FFM compared with DXA in those with greater body fat. Standard BIA equations may not accurately estimate FFM and fat mass in men and women with AIDS wasting.

Health effects of depleted uranium on exposed Gulf War veterans.

A small group of Gulf War veterans possess retained fragments of depleted uranium (DU) shrapnel, the long-term health consequences of which are undetermined. We evaluated the clinical health effects of DU exposure in Gulf War veterans compared with nonexposed Gulf War veterans. History and follow-up medical examination were performed on 29 exposed veterans and 38 nonexposed veterans. Outcome measures employed were urinary uranium determinations, clinical laboratory values, and psychiatric and neurocognitive assessment. DU-exposed Gulf War veterans with retained metal shrapnel fragments are excreting elevated levels of urinary uranium 7 years after first exposure (range 0.01-30.7 microg/g creatinine vs 0.01- 0.05 microg/g creatinine in the nonexposed). The persistence of the elevated urine uranium suggests on-going mobilization from a storage depot which results in a chronic systemic exposure. Adverse effects in the kidney, a presumed target organ, are not present at this time, though other effects are observed. Neurocognitive examinations demonstrated a statistical relationship between urine uranium levels and lowered performance on computerized tests assessing performance efficiency. Elevated urinary uranium was statistically related to a high prolactin level (>1.6 ng/ml; P=0.04). More than 7 years after first exposure, DU-exposed Gulf War veterans with retained metal fragments continue to excrete elevated concentrations of urinary uranium. Effects related to this are subtle perturbations in the reproductive and central nervous systems.

Quantitative assessment of cross-sectional muscle area, functional status, and muscle strength in men with the acquired immunodeficiency syndrome wasting syndrome.

The acquired immunodeficiency syndrome wasting syndrome (AWS) in men is characterized by the loss of lean body mass out of proportion to weight. Although the wasting syndrome has been thought to contribute to reduced functional capacity, the relationships among lean body mass, muscle size, functional status, and regional muscle strength have not previously been investigated in this population. In this study, 24 eugonadal men with the AWS (weight <90% of the ideal body weight or weight loss >10% from preillness maximum) underwent determination of body composition by dual energy x-ray absorptiometry (DXA), 40K isotope analysis, urinary creatinine excretion, and quantitative computed tomographic analysis of cross-sectional muscle areas of the midarm and thigh. Overall exercise functional capacity was evaluated using the 6-min walk test, and performance of upper and lower extremities was determined with the quantitative muscle function test. Subjects were 37 +/- 1 yr of age and weighed 95.5 +/- 3.0% of ideal body weight, with a body mass index of 21.9 +/- 0.7 kg/m2 and an average weight loss of 15 +/- 1%. The mean CD4 count among the subjects was 354 +/- 70 cells/mm3, and viral load was 58,561 +/- 32,205 copies. Sixty-two percent of subjects were receiving protease inhibitor therapy. The subjects demonstrated 90% of the expected muscle mass by the creatinine height index method. Overall performance status on the Karnofsky scale was highly correlated to weight (r = 0.51; P = 0.018; by body mass index), lean body mass (r = 0.46; P = 0.036; by DXA), and body cell mass (r = 0.47; P = 0.037; by 40K isotope analysis). Cross-sectional muscle area of the upper extremity was the best predictor (P < 0.001) of Karnofsky score, accounting for 52% of the variability in a stepwise regression analysis. Upper body muscle strength was most significantly predicted by lean body mass (by DXA; r2 = 0.78; P < 0.0001), whereas lower body strength and performance on the 6-min walk test were best predicted by lower extremity cross-sectional muscle area (r2 = 0.70; P < 0.0001 and r2 = 0.26; P = 0.030, respectively). These data demonstrate that cross-sectional muscle area is highly predictive of functional status and muscle strength in men with the AWS.

Effects of androgen administration in men with the AIDS wasting syndrome. A randomized, double-blind, placebo-controlled trial.

BACKGROUND: Development of successful anabolic strategies to reverse the loss of lean body mass is of critical importance to increase survival in men with the AIDS wasting syndrome. Hypogonadism, an acquired endocrine deficiency state characterized by loss of testosterone, occurs in more than half of all men with advanced HIV disease. It is unknown whether testosterone deficiency contributes to the profound catabolic state and loss of lean body mass associated with the AIDS wasting syndrome. OBJECTIVE: To investigate the effects of physiologic testosterone administration on body composition, exercise functional capacity, and quality of life in androgen-deficient men with the AIDS wasting syndrome. DESIGN: Randomized, double-blind, placebo-controlled study. SETTING: University medical center. PATIENTS: 51 HIV-positive men (age 42 +/- 8 years) with wasting (body weight < 90% of ideal body weight or weight loss > 10% of baseline weight) and a free testosterone level less than 42 pmol/L (normal range for men 18 to 49 years of age, 42 to 121 pmol/L [12.0 to 35.0 pg/mL]). INTERVENTION: Patients were randomly assigned to receive testosterone enanthate, 300 mg, or placebo intramuscularly every 3 weeks for 6 months. MEASUREMENTS: Change in fat-free mass was the primary end point. Secondary clinical end points were weight, lean body mass, muscle mass, exercise functional capacity, and change in perceived quality of life. Virologic variables were assessed by CD4 count and viral load. RESULTS: Compared with patients who received placebo, testosterone-treated patients gained fat-free mass (-0.6 kg and 2.0 kg; P = 0.036), lean body mass (0.0 kg and 1.9 kg; P = 0.041), and muscle mass (-0.8 kg and 2.4 kg; P = 0.005). The changes in weight, fat mass, total-body water content, and exercise functional capacity did not significantly differ between the groups. Patients who received testosterone reported benefit from the treatment (P = 0.036), feeling better (P = 0.033), improved quality of life (P = 0.040), and improved appearance (P = 0.021). Testosterone was well tolerated in all patients. CONCLUSIONS: Physiologic testosterone administration increases lean body mass and improves quality of life among androgen-deficient men with the AIDS wasting syndrome.

Quality control of spirometry testing in the registry for patients with severe alpha1-antitrypsin deficiency. alpha1-Antitrypsin Deficiency Registry Study Group.

As part of the multicenter National Heart, Lung, and Blood Institute registry of patients with severe deficiency of alpha1-antitrypsin with 1,129 enrollees, this report describes measures undertaken to achieve high-quality FEV1 measurements, the rates of satisfying reproducibility and acceptability criteria, and clinical features of participants unable to achieve reproducible FEV1 values at baseline. Spirograms were performed both before and after an inhaled bronchodilator in enrollees followed up at 37 participating clinical centers. Using a reproducibility criterion of < 100 mL or 5% (whichever greater), high reproducibility rates for FEV1 measurements at baseline were observed for both prebronchodilator (95.0% of 1,090 sessions) and postbronchodilator measurements (95.7% of 1,077 sessions). Using the more recently published reproducibility criterion of < or = 200 mL, reproducibility rates were even higher. Eighty-four percent of clinical centers submitted FEV1 values that satisfied reproducibility criteria for at least 90% of spirograms. Also, the mean coefficient of variation for prebronchodilator FEV1 values measured over serial visits separated by up to 9 months was 5.6% for participants with baseline FEV1 55 to 90% predicted. This degree of reproducibility is similar to that observed in the Lung Health Study. Rates of satisfying acceptability criteria for prebronchodilator spirograms were lower, almost universally (98% of tests) due to failure to achieve end-of-test criteria (which usually required 15 s of expiration in this population with mean FEV1 = 42.6+/-29.6% [SD] predicted). Multivariate logistic regression models show that clinical correlates of failure to achieve reproducible prebronchodilator FEV1 efforts include symptoms of chronic wheeze, chronic cough, and chronic phlegm, and the degree of airflow obstruction. We conclude that highly reproducible FEV1 measurements are achievable in a population with severe airflow obstruction despite the additional challenges posed by testing in multiple centers on a variety of spirometers. Furthermore, the difficulty of satisfying end-of-test criteria in a large cohort with severe airflow obstruction did not preclude achieving high rates of reproducibility for FEV1 measurements. Finally, our study confirms prior observations that failure to achieve reproducible efforts is associated with the presence of pulmonary symptoms and the degree of airflow obstruction. Thus, excluding patients with nonreproducible FEV1 efforts from epidemiologic studies would bias results by including only healthier participants.

Peak expiratory flow from maximum expiratory flow volume curves in a community population: cross-sectional and longitudinal analyses.

The data from a longitudinal population study in Tucson, Arizona, were used to describe the development and decline with age of the peak expiratory flows (PEF) from maximum expiratory flow-volume (MEFV) curves derived using a computer-linked pneumotachometer. Subjects had performed at least one technically acceptable MEFV test in 9 of the first 11 surveys (1972-1989). There were 2,724 subjects with adequate MEFV curves, and thus PEF, in the first survey, but only 1315 in the 11th survey. The subjects were stratified based on responses to questionnaires into nonsmoking healthy subjects and others. The PEF were analysed cross-sectionally and longitudinally using data from the 6th-11th surveys (1979-1989). For longitudinal analysis, the reference population had 397 males with 1,153 observations, and 534 females with 1,700 observations. The resulting equations were compared, evaluating differences between the longitudinal and cross-sectional equations, and between reference and nonreference longitudinal populations. The results show that there were effort-dependent effects in absolute values of PEF, even after editing. Nevertheless, as with most MEFV measures in reference populations, PEF had an early increase in the rate of development, followed by a plateau phase, followed by a constant rate of decline. The ages at which changes in growth rates of PEF occurred differed by gender. The longitudinal data in adults showed a less steep decline with age compared to the cross-sectional data, as found previously for the other MEFV variables. Males in the nonreference group did not reach the same maximum level and had a steeper decline throughout adult life than did males in the reference group; females were similar. Asthmatics of both genders had slightly greater declines compared to the other nonreference subjects.

Loss of lean body and muscle mass correlates with androgen levels in hypogonadal men with acquired immunodeficiency syndrome and wasting.

The acquired immunodeficiency syndrome (AIDS) wasting syndrome (AWS) is a devastating complication of human immunodeficiency virus infection characterized by a disproportionate decrease in lean body mass. The pathogenesis of the AWS is unknown, but recent data suggest that endogenous secretion of the potent anabolic hormone, testosterone; is decreased in 30-50% of men with AIDS. However, it is unknown whether decreased androgen levels are associated with decreased lean body mass and/or functional decreases in muscle strength and aerobic capacity in hypogonadal men with the AWS. In addition, testosterone is known to have stimulatory effects on GH secretion, and the loss of these effects on the GH-insulin-like growth factor I (IGF-I) axis may be an additional mechanism of decreased lean body mass in this population. Twenty hypogonadal subjects (free-testosterone < 12 pg/mL) with weight loss > 10% of preillness weight or absolute weight < 90% ideal body weight (IBW) were enrolled in the study. None of the subjects were receiving Megace. Lean body mass and fat-free mass were determined by potassium-40 isotope analysis (40K) and dual-energy x-ray absorptiometry, respectively, and analyzed with respect to gonadal function by linear regression analysis. Muscle mass was determined by urinary creatinine excretion, and exercise functional capacity was assessed by a 6-min walk test, a sit-to-stand test, and a timed get-up-and-go test. Results also were compared with gonadal function by regression analysis. IGF-I and mean overnight GH levels, determined from frequent sampling (q20 min from 2000-0800 h), were compared with results obtained from age- and sex-matched normal controls. Subjects were 26-58 yr of age (39 +/- 7 yr, mean +/- SD) with a CD4 cell count of 150 +/- 186 cells/mm3. Serum levels of FSH were elevated in 30% of the subjects. Muscle mass was significantly reduced, compared with expected mass for height (23.3 +/- 5.5 vs. 29.3 +/- 1.7 kg, P = 0.0001) and was decreased disproportionately to weight (77% of expected value for muscle mass vs. 93% of expected value for weight). Free-testosterone levels were correlated with total body potassium (R = 0.45, P < 0.05) and muscle mass (R = 0.45, P < 0.05). Total-testosterone levels were correlated with exercise functional capacity (R = 0.64, P = 0.01 for the sit-to-stand test and R = 0.53, P < 0.05 for the 6-min walk test). Mean GH levels were significantly increased (3.03 +/- 1.76 vs. 0.90 +/- 0.37 ng/mL, P < 0.001) and IGF-I levels decreased (167 +/- 66 vs. 225 +/- 69 ng/mL, P < 0.01), compared with age- and sex-matched eugonadal controls. GH levels were inversely correlated with caloric intake (R = -0.60, P = 0.02) and percent fat mass by dual-energy x-ray absorptiometry (R = 0.58, P = 0.02). Six additional hypogonadal subjects receiving Megace for AIDS wasting were analyzed separately. Nutritional status and parameters of body composition were compared in the Megace and non-Megace-treated subjects. No significant differences in caloric intake, lean body mass, fat mass, or muscle mass were demonstrated. These data demonstrate that changes in body composition, including loss of lean body and muscle mass, and deterioration in exercise functional capacity are highly correlated with androgen levels in hypogonadal men with the AWS. Furthermore, our data demonstrate significantly increased GH levels and decreased IGF-I in association with low weight in this population. These data suggest that androgen deficiency combined with classical GH resistance may contribute to the critical loss of lean body and muscle mass in hypogonadal men with the AWS. These data are the first to link muscle and lean body wasting with progressive gonadal dysfunction among the large percentage of men with AIDS wasting who are hypogonadal. This demonstrates the need for additional studies to determine the efficacy of gonadal steroid replacement to increase lean body mass in this population.

Early childhood respiratory symptoms and the subsequent diagnosis of asthma.

BACKGROUND: Respiratory symptoms are frequent in very young children, and the relation of these symptoms to later asthma in some of these children is unknown. OBJECTIVE: The aim of the study was to describe the natural history of respiratory symptoms in a community-based sample of young children who were prospectively observed for as long as 11 years. METHODS: Subjects were participants in the Tucson Epidemiologic Study of Airways Obstructive Disease. They were under 5 years of age at enrollment and were studied by means of a parent-administered mail survey instrument every 1 to 2 years for 3 to 11 years. RESULTS: Among subjects younger than 1 year of age, no single respiratory symptom, such as cough or wheeze only with colds, significantly increased the risk of a subsequent diagnosis of asthma. Among 1- and 2-year-olds, however, those with wheeze only with colds and those with attacks of shortness of breath with wheeze were more likely to be diagnosed with asthma later when compared with children without those symptoms (odds ration = 2.1; p < 0.05 for wheeze only with colds). At ages 3 to 4 years, symptoms were even more strongly associated with subsequent asthma (odds ratio = 7.2; p < 0.0001 for attacks of shortness of breath with wheeze). CONCLUSION: Although respiratory symptoms reported by parents very early in life are not significantly associated with future asthma, those symptoms that begin at or persist through ages 3 to 4 years are.

Rates of decline in lung function among subjects who restart cigarette smoking.

Several studies have demonstrated that smokers who are able to break the habit generally experience reductions in respiratory symptoms and improvement in pulmonary function; however, far less attention has been given to smokers who are unsuccessful in their attempts at quitting. Recent reports have suggested that these subjects (restarters) may have steeper rates of decline in pulmonary function than subjects never attempting to quit smoking. In this study, we compared rates of decline in FEV1 between restarters and subjects who remained current, ex-smokers, or never-smokers throughout the observation period. The results showed that, in both sexes, subjects who attempt to quit the habit and then restart have significantly steeper rates of decline in their FEV1 than subjects who continue smoking uninterrupted. Female restarters also have significantly steeper rates of decline in FEV1 than ex-smokers. These effects were independent of the amount smoked and respiratory diseases.

The relationship between parental and children's serum IgE and asthma.

This paper examines the familial aggregation of physician-diagnosed asthma in relation to the age- and sex-standardized total serum IgE levels of children and their parents in a sample of the general population in Tucson, Arizona, that has been followed in a longitudinal study for over 20 yr. There were 591 nuclear families containing 1,177 children who provided information about the presence or absence of a physician diagnosis of asthma. The serum IgE data were less complete: both parents and one or more of their children in 251 of the nuclear families, containing 468 children, had serum IgE levels measured. There was a very strong tendency for asthmatic patients to have asthmatic children, but only a small part of this appeared to be related to the familial aggregation of total serum IgE. In the absence of an asthmatic parent, there was a slight but significantly higher prevalence of asthma in children of whom both parents had IgE levels in the highest tertile. Very high rates of children's asthma depended on there being an asthmatic parent who also had at least moderate levels of serum IgE. It was also shown that asthmatic children have considerably higher total IgE levels than would be expected on the basis of their parents' IgE levels alone. The data appear compatible with several familial-aggregation hypotheses and a strong environmental influence determining which children are likely to develop asthma. We speculate that the inflammation in the airways of asthmatic patients itself tends to increase the serum IgE level, possibly secondary to mediators that it generates.

Relation of the course of bronchial responsiveness from age 9 to age 15 to allergy.

Bronchial responsiveness to methacholine was measured in a birth cohort of New Zealand children at ages 9, 11, 13, and 15. Overall bronchial hyperresponsiveness (BHR) decreased with age. While the response at age 9 was significantly related to responsiveness, symptom severity, and low lung function at age 15, these relationships were much closer when bronchial response levels after age 9 were taken into account. Also, among children who were unresponsive to methacholine at age 15, those with previous BHR had more frequent wheeze and lower lung function than those whose previous tests were all unresponsive. Both the overall tendency to BHR and the tendency to retain BHR were closely related to high serum IgE levels (determined at age 11) and to positive allergy skin tests (determined at age 13). These evidences of allergy, closely related to the severity and course of methacholine response, appeared to be important determinants of the frequency of wheeze and the degree of impairment of lung function at the end of follow-up. In view of the variability in BHR, a single estimate of bronchial responsiveness taken at an arbitrary point in time may not be an accurate index of the overall tendency to BHR.

Adverse effects of eosinophilia and smoking on the natural history of newly diagnosed chronic bronchitis.

BACKGROUND: Little is known about risk factors for the progression of disease in individuals with newly developed chronic bronchitis (CB). In addition to the effects of smoking, there was specific clinical and epidemiologic interest in the importance of traits such as eosinophilia and wheezing, more commonly associated with asthma, in the progression of this disease. METHODS: We evaluated adult individuals with and without diagnosed CB longitudinally in a representative community population in Tucson, Ariz. These subjects were followed up for 13 years since 1972. Because we were interested in CB specifically, those with diagnoses of emphysema and asthma were removed from the data set. Initial level of FEV1 (%FEV1) and slopes in FEV1 were corrected for covariates and other important variables. RESULTS: As expected, persistent and newly diagnosed CB was significantly more common in current and ex-smokers. Furthermore, initial lung function was lower, and decline in FEV1 was steeper in smokers with persistent and newly diagnosed CB. Newly diagnosed cases had steeper declines in FEV1 (-6.84 mL/yr below grand mean of -11.18 mL/yr) than normal subjects (+0.95 mL/yr). The incidence rate of newly diagnosed CB was significantly higher in those with eosinophilia (13.7%) than without eosinophilia (6.7%). Finally, new cases with eosinophilia had similar initial %FEV1 (95.4 +/- 1%) but much larger declines in function than new cases without eosinophilia: -24.5 versus -16.6 mL/yr. Adverse effects of wheeze were largely explained by smoking and eosinophilia. CONCLUSION: Eosinophilia is an important aspect of CB in addition to smoking, and it should be considered in its evaluation. The presence of eosinophilia in newly diagnosed CB, with or without wheeze, may warn the clinician of the possibility of a rapid decline in FEV1.

Longitudinal evaluation of the association between pulmonary function and total serum IgE.

The role of immunoglobulin E (IgE) in the development and course of impaired ventilatory function and chronic obstructive pulmonary disease (COPD) required further study. This role has been examined in the longitudinal Tucson Epidemiological Study of Airways Obstructive Disease, which started in 1972. The association between IgE and longitudinal changes in pulmonary function measures was examined in subjects in the community population sample in Tucson who had an initial age of 35 or more. There were a total of 1,533 such subjects with lung function tests over the 20 yr period who also had IgE determinations. A significant inverse association was found between total serum IgE and FEV1/FVC that was independent of smoking and asthma status. The finding was statistically separate from the relation with age in all but elderly current smokers (age > 55). The magnitude of this effect in nonasthmatic subjects was relatively small. For asthmatic subjects, however, the inverse association was larger in both current and never smokers. Subjects excluded from the current analysis either did not have an IgE measurement and/or had no pulmonary function values after 35 yr of age. These findings suggest that higher IgE levels may indicate the presence of a disease process that may involve inflammation and/or other mechanisms related to IgE production, which impair lung function over time. However, in this study we were not able to account for possible parental or inheritance contributions to increases in total IgE, which have been shown to be important.

Relations of bronchial responsiveness to allergy skin test reactivity, lung function, respiratory symptoms, and diagnoses in thirteen-year-old New Zealand children.

BACKGROUND: Many factors have been found to relate univariately to bronchial responsiveness (BR), but their independent relationships are often unclear because many are interrelated. OBJECTIVE: The purpose of this study was to present a multivariate analysis of the closeness of the association of various factors that are related univariately to BR, including allergy skin tests. METHODS: The results of methacholine challenge were transformed into a continuous variable (BRindex), which has a nearly Gaussian distribution. With stepwise multiple regression, the closeness of the association of the independent variables with BRindex was evaluated. RESULTS: Of the 11 skin tests applied, four showed independent relationships to BRindex (mite, cat, dog, and Aspergillus species). The sizes of these skin test reactions were correlated with BRindex, and their sum appeared to maximize the overall correlation of allergy skin tests with BRindex (r = 0.516). The lowness of the ratio of forced expiratory volume in 1 second to vital capacity and of percent predicted forced expiratory volume in 1 second added significantly to the skin tests in correlating with BRindex, (multiple r = 0.621). Adding diagnoses and symptoms increased the multiple r to 0.685. CONCLUSIONS: The size of the reactions to the four skin tests noted above showed much closer correlations with BR than total serum IgE had shown at age 11, and the relationship was present in asthmatic and nonasthmatic subjects.

Relationships between total serum IgE, atopy, and smoking: a twenty-year follow-up analysis.

BACKGROUND: A number of cross-sectional studies have demonstrated that higher levels of IgE are found in subjects who currently smoke cigarettes and/or who are atopic and that IgE levels decline with age. OBJECTIVE: This report examines the interactions among atopic status, smoking, and IgE with longitudinal data and methods. METHODS: Subjects were participants in the Tucson Epidemiological Study of Airways Obstructive Disease and were 6 years of age and older. Total serum IgE measures and allergen skin test results were obtained during three surveys spanning a period of up to 20 years. RESULTS: The results showed no significant gender differences between nonatopic nonsmoking subjects, who were considered the reference group. Nonatopic current smokers had IgE levels similar to those of the reference subjects initially, but IgE levels did not decline with age at the same rate as in the reference subjects, causing significant differences at older ages. There was a significant relationship between number of cigarettes smoked and IgE level. CONCLUSIONS: Atopy and smoking are both associated with elevated total serum IgE levels. Although the exact mechanism for elevated IgE levels in smokers is not known, the significant dose relationship is suggestive of a causal association.