Social Cognitive Constructs Did Not Mediate the BEAT Cancer Intervention Effects on Objective Physical Activity Behavior Based on Multivariable Path Analysis.

BACKGROUND: Most breast cancer survivors do not meet physical activity recommendations. Understanding mediators of physical activity behavior change can improve interventions designed to increase physical activity in this at-risk population. PURPOSE: Study aims were to determine the 3-month Better Exercise Adherence after Treatment for Cancer (BEAT Cancer) behavior change intervention effects on social cognitive theory constructs and the mediating role of any changes on the increase in accelerometer-measured physical activity previously reported. METHODS: Post-treatment breast cancer survivors (N = 222) were randomized to BEAT Cancer or usual care. Assessments occurred at baseline, 3 months (M3), and 6 months (M6). Adjusted linear mixed model analysis of variance determined intervention effects on walking self-efficacy, outcome expectations, goal setting, and perceived barrier interference at M3. Path analysis determined mediation of intervention effects on physical activity at M6 by changes in social cognitive constructs during the intervention (i.e., baseline to M3). RESULTS: BEAT Cancer significantly improved self-efficacy, goals, negative outcome expectations, and barriers. Total path analysis model explained 24 % of the variance in M6 physical activity. There were significant paths from randomized intervention group to self-efficacy (ß = 0.15, p < .05) and barriers (ß = -0.22, p < .01). Barriers demonstrated a borderline significant association with M6 physical activity (ß = -0.24, p = .05). No statistically significant indirect effects were found. CONCLUSIONS: Although BEAT Cancer significantly improved social cognitive constructs, no significant indirect effects on physical activity improvements 3 months post-intervention were observed (NCT00929617).

Effects of the BEAT Cancer physical activity behavior change intervention on physical activity, aerobic fitness, and quality of life in breast cancer survivors: a multicenter randomized controlled trial.

Most breast cancer survivors (BCS) are not meeting recommended physical activity guidelines. Here, we report the effects of the Better Exercise Adherence after Treatment for Cancer (BEAT Cancer) behavior change intervention on physical activity, aerobic fitness, and quality of life (QoL). We randomized 222 post-primary treatment BCS to the 3-month intervention (BEAT Cancer) or usual care (UC). BEAT Cancer combined supervised exercise, face-to-face counseling, and group discussions with tapering to home-based exercise. Assessments at baseline, immediately post-intervention (month 3; M3), and 3 months post-intervention (month 6; M6) included accelerometer and self-reported physical activity, submaximal treadmill test, and QoL [Functional Assessment of Cancer Therapy (FACT)-Breast scale]. Adjusted linear mixed-model analyses demonstrated significant effects of BEAT Cancer compared to UC on weekly minutes of ≥ moderate intensity physical activity at M3 by accelerometer [mean between group difference (M) = +41; 95 % confidence interval (CI) = 10-73; p = 0.010] and self-report (M = +93; CI = 62-123; p < 0.001). Statistical significance remained at M6 for self-reported physical activity (M = +74; CI = 43-105; p < 0.001). BEAT Cancer participants were significantly more likely to meet physical activity recommendations at both time points [accelerometer M3 adjusted odds ratio (OR) = 2.2; CI = 1.0-4.8 and M6 adjusted OR = 2.4; CI = 1.1-5.3; self-report M3 adjusted OR = 5.2; CI = 2.6-10.4 and M6 adjusted OR = 4.8; CI = 2.3-10.0]. BEAT Cancer significantly improved fitness at M6 (M = +1.8 ml/kg/min; CI = 0.8-2.8; p = 0.001) and QoL at M3 and M6 (M = +6.4; CI = 3.1-9.7; p < 0.001 and M = +3.8; CI = 0.5-7.2; p = 0.025, respectively). The BEAT Cancer intervention significantly improved physical activity, fitness, and QoL with benefits continuing 3 months post-intervention.

Inflammation and psychosocial factors mediate exercise effects on sleep quality in breast cancer survivors: pilot randomized controlled trial.

OBJECTIVE: To improve mechanistic understanding, this pilot randomized controlled trial examined mediators of an exercise intervention effects on sleep in breast cancer survivors (BCS). METHODS: Forty-six postmenopausal BCS (≤Stage II, off primary treatment) were randomized to a 3-month exercise intervention or control group. Intervention included 160 min/week of moderate intensity aerobic walking, twice weekly resistance training (resistance bands), and six discussion groups (to improve adherence). Blinded assessments at baseline and post-intervention included sleep disturbance (PSQI and PROMIS®), objective sleep quality (accelerometer), serum cytokines, accelerometer physical activity, cardiorespiratory fitness, body composition, fatigue, and psychosocial factors. Mediation was tested using Freedman-Schatzkin difference-in-coefficients tests. RESULTS: When compared with control, the intervention group demonstrated a significant increase in PSQI sleep duration (i.e., fewer hours of sleep/night) (d = 0.73, p = .03). Medium to large but non-significant standardized effect sizes were noted for PSQI daytime somnolence (d = -0.63, p = .05) and accelerometer latency (d = -0.49, p = .14). No statistically significant mediators were detected for PSQI sleep duration score or accelerometer latency. Daytime somnolence was mediated by tumor necrosis factor-alpha (mediated 23% of intervention effect, p < .05), interleukin (IL)-6:IL-10 (16%, p < .01), IL-8:IL-10 (26%, p < .01), and fatigue (38%, p < .05). Mediating or enhancing relationships for several of the sleep outcomes were noted for accelerometer physical activity, PROMIS® fatigue, exercise social support, and/or physical activity enjoyment. CONCLUSIONS: Inflammation and psychosocial factors may mediate or enhance sleep response to our exercise intervention. Further study is warranted to confirm our results and translate our findings into more effective interventions aimed at improving sleep quality in BCS.

Physical activity and health outcomes three months after completing a physical activity behavior change intervention: persistent and delayed effects.

PURPOSE: We previously reported the effectiveness of a 12-week physical activity behavior change intervention for breast cancer survivors postintervention with this report, aiming to determine delayed and/or persistent effects 3 months after intervention completion. METHODS: Forty-one sedentary women with stage I, II, or IIIA breast cancer currently receiving hormonal therapy were randomly assigned to receive the 12-week Better Exercise Adherence after Treatment for Cancer intervention or usual care. Assessments occurred at baseline, postintervention, and 3 months postintervention. RESULTS: Weekly minutes of greater than or equal to moderate intensity physical activity measured by accelerometer showed a significant group by time interaction (F = 3.51; P = 0.035; between group difference in the mean change from baseline to 3 months postintervention, 100.1 minute, P = 0.012). Significant group by time interactions also showed sustained improvements from baseline to 3 months postintervention in strength (F = 3.82; P = 0.027; between group difference, 11.2 kg; P = 0.026), waist-to-hip ratio (F = 3.36; P = 0.041; between group difference, -0.04; P = 0.094), and social well-being (F = 4.22; P = 0.023; between group difference, 3.9; P = 0.039). A delayed reduction in lower extremity dysfunction 3 months postintervention was noted (F = 3.24; P = 0.045; between group difference in the mean change from postintervention to 3 months follow-up; P = -7.6; P = 0.015). No group by time effect was noted for fitness, body mass index, percent fat, bone density, total quality of life (Functional Assessment of Cancer Therapy-General), fatigue, endocrine symptoms, cognitive function, or sleep. CONCLUSIONS: The intervention resulted in sustained improvements in physical activity, strength, central adiposity, and social well-being with lower extremity function benefits appearing 3 months after intervention completion. Testing translation in a multisite study is warranted.

Characteristics of smokers calling a national reactive telephone helpline.

PURPOSE: Although reactive telephone helplines for quitting smoking are increasingly popular in the United States, the characteristics of callers using this resource have not been adequately studied. The objective of this study was to describe the characteristics of the current smokers calling a national reactive telephone helpline (i.e., study population). DESIGN AND SETTING: In this cross-sectional study, information was obtained from eligible participants telephonically. SUBJECTS: The study included 890 adult current smokers who were new callers to a national reactive helpline. MEASURES: The information collected included selected demographic and smoking-related characteristics. ANALYSIS: The proportions of the above characteristics were analyzed. RESULTS: There was a significant overepresentation of blacks, non-Hispanics, women, and urban residents, as well as poorer, older, less educated, and heavier smokers in the study population (p < .01 for all comparisons). CONCLUSIONS: Reactive telephone helplines may be preferentially used by population segments who are disadvantaged or smoke heavily and thus are in greatest need for assistance. These helplines may therefore fill a much-needed niche in the marketplace of smoking cessation strategies.

Acute anhydrous ammonia injury from accidents during illicit methamphetamine production.

BACKGROUND: Anhydrous ammonia (AA), a chemical commonly used in agriculture, is a key component in illicit methamphetamine production. Although injuries associated with AA exposure are well studied, AA injuries associated with incidents during illicit methamphetamine production have not been adequately described in the literature. OBJECTIVE: This study better characterizes AA injuries occurring in an agricultural region where illicit methamphetamine production is common. METHODS: We performed a cross-sectional study based on a chart review of 49 patients who were admitted to a tertiary hospital in Illinois with known or suspected exposures to chemical agents. Indices of morbidity were compared between injuries resulting from exposure to AA and injuries from other chemicals, and between AA injuries from incidents during illicit methamphetamine production and AA injuries from other causes. RESULTS: AA was the most common cause of chemical injury (41%; n=20/49). Incidents during illicit methamphetamine production were the most common cause of AA injury (75%; n=15/20). AA injury was associated with significantly greater morbidity compared to non-AA chemical injury. In addition, methamphetamine-related AA injury was associated with significantly greater morbidity compared to non-methamphetamine-related AA injury. CONCLUSION: Chemical burns during illicit methamphetamine production were the most common cause of both chemical and AA-related injury in our agricultural population and these injuries were associated with greater morbidity during hospitalization.

Sex- and race-related differences among smokers using a national helpline are not explained by socioeconomic status.

The bases for sex- and race-related differences in smoking behavior are not well understood. Studying the difference in smoking behavior among population segments may allow for effective utilization of resources towards quitting and help understand the cause of existing smoking-related disparities. Our objective was to evaluate whether sex- and race-related differences in smoking behavior were explained by socioeconomic status (SES), using a population of smokers that called a national reactive telephone helpline. This cross-sectional study evaluated 990 new callers to a helpline. Information on demographics and smoking behavior was collected by a telephone interview. Statistical techniques included t test, Chi square and regression analyses. Women and black smokers had lower SES than men and white smokers, respectively. Women smokers had lower rates of tobacco exposure and were more likely to be tempted to smoke by environmental cues. Blacks also had lower rates of tobacco exposure and reported a higher confidence in their ability to quit. Both men and black smokers were less likely to have used other methods of quitting before calling the helpline. These differences persisted after adjusting for SES. This study demonstrates that sex- and race-related differences in smoking among helpline callers are not explained by SES.

Asthma, allergy, and airway hyperresponsiveness are not linked to the beta(2)-adrenoceptor gene.

STUDY OBJECTIVES: To exclude genetic linkage between the beta(2)-adrenoceptor gene and asthma, allergy, and methacholine airway hyperresponsiveness. DESIGN: The current study used six distinct intragene markers within the beta(2)-adrenoceptor gene, and evaluated genetic linkage between the beta(2)-adrenoceptor and asthma, allergy, or methacholine airway hyperresponsiveness in eight multiplex families. PATIENTS: Forty-nine members of eight multiplex families with a high incidence of asthma. INTERVENTIONS: Phenotypes were characterized by history, physical examination, skin testing, pulmonary function tests, and methacholine inhalational challenge. Genetic loci were identified using restriction fragment length polymorphisms, denaturing gradient gel electrophoresis, and restriction enzyme digest of polymerase chain reaction-amplified fragments of the beta(2)-adrenoceptor gene. MEASUREMENTS AND RESULTS: Nonparametric analysis using computer analysis software found no evidence for linkage between these markers within the beta(2)-adrenoceptor gene and asthma. Parametric exclusion analysis using a dominant inheritance model resulted in large negative lod scores (- 6.74, - 19.44, and - 49.9, respectively) for tight linkage between asthma, allergy, or methacholine airway hyperresponsiveness and these polymorphic markers. CONCLUSIONS: These results indicate that asthma, allergy, and methacholine airway hyperresponsiveness are not linked to a dominant beta(2)-adrenoceptor gene with strong effect in these eight families with an inherited pattern of asthma.

Exploring social cognitive theory constructs for promoting exercise among breast cancer patients.

Physical activity during breast cancer treatment can significantly reduce treatment-related fatigue and improve quality of life. Unfortunately, the majority of women with breast cancer either do not exercise at all or exercise below recommended levels. Little is known about how to enhance physical activity among breast cancer patients. The social cognitive theory, a useful framework for the design of physical activity interventions, has not been studied among breast cancer patients. Our study purpose was to explore physical activity knowledge, attitudes, and behaviors among breast cancer patients during adjuvant therapy utilizing social cognitive theory constructs in preparation for a larger, survey study and future intervention research. Twelve breast cancer patients attended 1 of 3 focus group sessions. Focus group questions were based on the social cognitive theory constructs of self-efficacy, environment, behavioral capability, expectations, expectancies, self-control and performance, observational learning, and reinforcement. The focus group participants generally felt confident in their ability to exercise during treatment if fatigue, time management, and social networking were addressed. The majority of participants had not been given information related to exercise by their physicians during treatment. The participants felt that exercise was more beneficial than harmful during treatment, with the 2 most important benefits identified as reduced fatigue and the potential for improved survival. The use of reinforcements by participants was minimal. The participants consistently expressed the desire for education and guidance by knowledgeable staff during an exercise program. Walking was the most acceptable exercise modality. Social cognitive theory may be a useful framework for future study of exercise behavior among breast cancer patients and measurement of constructs related to this theory should be included in such studies. Future exercise intervention studies should consider the unique barriers and program preferences of breast cancer patients while focusing on self-efficacy, outcome expectations/ expectancies, observational learning, and reinforcements.

Biobehavioral factors mediate exercise effects on fatigue in breast cancer survivors.

PURPOSE: This study aimed to examine mediators of fatigue response to an exercise intervention for breast cancer survivors in a pilot randomized controlled trial. METHODS: Postmenopausal breast cancer survivors (n = 46; ≤stage 2), off primary treatment, and reporting fatigue and/or sleep dysfunction were randomized to a 3-month exercise intervention (160 min·wk of moderate-intensity aerobic walking, twice weekly resistance training with resistance bands) or control group. Six discussion group sessions provided behavioral support to improve adherence. Fatigue, serum cytokines, accelerometer physical activity, cardiorespiratory fitness, sleep dysfunction, and psychosocial factors were assessed at baseline and 3 months. RESULTS: The exercise intervention effect sizes for fatigue were as follows: fatigue intensity d = 0.30 (P = 0.34), interference d = -0.38 (P = 0.22), and general fatigue d = -0.49 (P = 0.13). Using the Freedman-Schatzkin difference-in-coefficients tests, increase in fatigue intensity was significantly mediated by interleukin 6 (IL-6) (82%), IL-10 (94%), IL-6/IL-10 (49%), and tumor necrosis factor-α (TNF-α):IL-10 (78%) with reduced sleep dysfunction increasing the relationship between intervention and fatigue intensity rather than mediating intervention effects (-88%). Decrease in fatigue interference was mediated by sleep dysfunction (35%), whereas IL-10 and pro-anti-inflammatory cytokine ratios increased the relationship between intervention and interference (-25% to -40%). The reduction in general fatigue was significantly mediated by minutes of physical activity (76%), sleep dysfunction (45%), and physical activity enjoyment (40%), with IL-10 (-40%) and IL-6/IL-10 (-11%) increasing the intervention-fatigue relationship. In the intervention group, higher baseline fatigue, anxiety, depression, and perceived exercise barrier interference predicted a greater decline in fatigue interference and/or general fatigue during the intervention. CONCLUSIONS: Biobehavioral factors mediated and enhanced intervention effects on fatigue, whereas psychosocial factors predicted fatigue response. Further study is warranted to confirm our results and to improve understanding of relationships that mediate and strengthen the intervention-fatigue association.

Effects of a physical activity behavior change intervention on inflammation and related health outcomes in breast cancer survivors: pilot randomized trial.

BACKGROUND: The goal of this pilot study was to determine the magnitude and direction of intervention effect sizes for inflammatory-related serum markers and relevant health outcomes among breast cancer survivors (BCSs) receiving a physical activity behavior change intervention compared with usual care. METHODS: This randomized controlled trial enrolled 28 stage I, II, or IIIA BCSs who were post-primary treatment and not regular exercisers. Participants were assigned to either a 3-month physical activity behavior change intervention group (ING) or usual care group (UCG). Intervention included supervised aerobic (150 weekly minutes, moderate-intensity) and resistance (2 sessions per week) exercise that gradually shifted to home-based exercise. Outcomes were assessed at baseline and 3 months. RESULTS: Cardiorespiratory fitness significantly improved in the ING versus the UCG (between-group difference = 3.8 mL/kg/min; d = 1.1; P = .015). Self-reported sleep latency was significantly reduced in the ING versus the UCG (between group difference = -0.5; d = -1.2; P = .02) as was serum leptin (between-group difference = -9.0 ng/mL; d = -1.0; P = .031). Small to medium nonsignificant negative effect sizes were noted for interleukin (IL)-10 and tumor necrosis factor (TNF)-α and ratios of IL-6 to IL-10, IL-8 to IL-10, and TNF-α to IL-10, whereas nonsignificant positive effect sizes were noted for IL-6 and high-molecular-weight adiponectin. CONCLUSIONS: Physical activity behavior change interventions in BCSs can achieve large effect size changes for several health outcomes. Although effect sizes for inflammatory markers were often small and not significant, changes were in the hypothesized direction for all except IL-6 and IL-10.

Pilot, randomized trial of resistance exercise during radiation therapy for head and neck cancer.

BACKGROUND: The purpose of this study was to determine the feasibility of a randomized trial of resistance exercise in patients with head and neck cancer receiving radiation. METHODS: Fifteen patients with head and neck cancer receiving radiation were randomized to resistance exercise (using resistance bands) or control group. Resistance exercise occurred at the radiation therapy site (weeks 1-6) and home (weeks 7-12). RESULTS: No serious adverse events occurred related to resistance exercise. Medium to large effect size differences favoring resistance exercise versus control group were noted for perceived fatigue at 6 weeks (smaller increase in fatigue for resistance exercise group; 7.4 vs 15.4, effect size [d] = -0.64), quality of life at 6 weeks (-7.0 vs -14.4, d = 0.52), and chair rise time (seconds) at 6 and 12 weeks (-1.6 vs 0.4, d = -.63 and -1.9 vs 0.1, d = -0.60, respectively). CONCLUSIONS: Resistance exercise is safe and feasible in patients with head and neck cancer receiving radiation; a definitive trial is warranted.

Better exercise adherence after treatment for cancer (BEAT Cancer) study: rationale, design, and methods.

Most breast cancer survivors do not engage in regular physical activity. Our physical activity behavior change intervention for breast cancer survivors significantly improved physical activity and health outcomes post-intervention during a pilot, feasibility study. Testing in additional sites with a larger sample and longer follow-up is warranted to confirm program effectiveness short and longer term. Importantly, the pilot intervention resulted in changes in physical activity and social cognitive theory constructs, enhancing our potential for testing mechanisms mediating physical activity behavior change. Here, we report the rationale, design, and methods for a two-site, randomized controlled trial comparing the effects of the BEAT Cancer physical activity behavior change intervention to usual care on short and longer term physical activity adherence among breast cancer survivors. Secondary aims include examining social cognitive theory mechanisms of physical activity behavior change and health benefits of the intervention. Study recruitment goal is 256 breast cancer survivors with a history of ductal carcinoma in situ or Stage I, II, or IIIA disease who have completed primary cancer treatment. Outcome measures are obtained at baseline, 3 months (i.e., immediately post-intervention), 6 months, and 12 months and include physical activity, psychosocial factors, fatigue, sleep quality, lower extremity joint dysfunction, cardiorespiratory fitness, muscle strength, and waist-to-hip ratio. Confirming behavior change effectiveness, health effects, and underlying mechanisms of physical activity behavior change interventions will facilitate translation to community settings for improving the health and well-being of breast cancer survivors.

Reduced barriers mediated physical activity maintenance among breast cancer survivors.

To better understand mechanisms of physical activity (PA) behavior change in breast cancer survivors, we examined mediation of a successful PA behavior change intervention by social cognitive theory (SCT) constructs. Our exploratory study randomized 41 breast cancer survivors to receive the 3-month intervention (INT) or usual care (UC). We used the Freedman and Schatzkin approach to examine mediation of intervention effect on PA 3 months postintervention by changes in SCT constructs from baseline to immediately postintervention. Compared with UC, the INT group reported lower barriers interference (mean difference = -7.8, 95% CI [-15.1, -0.4], d = -0.67, p = .04) and greater PA enjoyment (mean difference = 0.7, 95% CI [0, 1.5], d = 0.61, p = .06). Barriers interference mediated 39% (p = .004) of the intervention effect on PA 3 months postintervention. PA enjoyment was not a significant mediator. Reducing barriers to PA partially explained our intervention effect.

"Real-world" effectiveness of reactive telephone counseling for smoking cessation: a randomized controlled trial.

BACKGROUND: Reactive telephone helplines for smoking cessation (where all calls to counselors are smoker initiated) are increasingly used in the United States. However, limited data from randomized controlled trials are available on their effectiveness. The study objective was to evaluate the real-world effectiveness of reactive telephone counseling for smoking cessation using a randomized controlled trial study design. METHODS: The study was implemented during a period from 2003 to 2006 to evaluate a reactive telephone helpline run by the American Lung Association chapter of Illinois-Iowa. The 990 new callers, all adult current smokers who called the helpline, were randomized on their first call into one of the two following groups: a control group that received only mailed self-help literature (n = 496); and a study group that received supplemental live reactive telephone counseling (n = 494). Telephone follow-up was completed at 1, 3, 6, and 12 months after study enrollment by interviewers blinded to group assignment. Seven-day point prevalence rates of self-reported abstinence at follow-up evaluations were compared between the two groups using an intent-to-treat design. RESULTS: The two groups did not differ significantly in baseline demographics and smoking-related behavior. The abstinence rates (ranging between 0.09 and 0.15) were not significantly different between the two groups at 1-, 3-, 6-, and 12-month follow-up evaluations. Post hoc subgroup analysis showed that black callers had lower abstinence rates at the 3- and 12-month follow-up evaluations as compared with white callers. CONCLUSION: Supplemental live, reactive telephone counseling does not provide greater success in smoking cessation than self-help educational materials alone.

A randomized trial to increase physical activity in breast cancer survivors.

PURPOSE: Interventions to increase physical activity among breast cancer survivors are needed to improve health and quality of life and possibly to reduce the risk of disease recurrence and early mortality. Therefore, we report the feasibility and preliminary outcomes of a pilot randomized trial designed to increase physical activity in sedentary breast cancer survivors receiving hormone therapy. METHODS: Forty-one sedentary women on estrogen receptor modulators or aromatase inhibitors for stage I, II, or IIIA breast cancer were randomly assigned to receive a 12-wk multidisciplinary physical activity behavior change intervention or usual care. RESULTS: Recruitment was 34%, intervention adherence was 99%, and complete follow-up data were obtained on 93%. Most participants (93%) were white with mean age of 53 +/- 9 yr. Differences favoring the intervention group were noted for accelerometer physical activity counts (mean difference = 72,103; 95% confidence interval (CI) = 25,383-119,000; effect size (d) = 1.02; P = 0.004), aerobic fitness (mean difference = 2.9; 95% CI = -0.1 to 5.8; d = 0.64; P = 0.058), back/leg muscle strength (mean difference = 12.3; 95% CI = 0.4-15.9; d = 0.81; P = 0.017), waist-to-hip ratio (mean difference = -0.05; 95% CI = -0.01 to -0.08; d = -0.77; P = 0.018), and social well-being (mean difference = 2.0; 95% CI = 0.3-3.8; d = 0.76; P = 0.03). However, the intervention group also reported a greater increase in joint stiffness (mean difference = 1.1; 95% CI = 0.1-2.2; d = 0.70; P = 0.04). CONCLUSIONS: A behavior change intervention for breast cancer survivors based on the social cognitive theory is feasible and results in potentially meaningful improvements in physical activity and selected health outcomes. Confirmation in a larger study is warranted.

Effect of change of reference standard to NHANES III on interpretation of spirometric 'abnormality'.

The American Thoracic Society has recently recommended the use of NHANES III spirometric reference standard in the United States. The objective of this study was to better quantify the well-known 'problem' of the change in interpretation of spirometry, as a consequence of the change from the other commonly used reference standards (Morris, Kory, Crapo, Knudson 1976, and Knudson 1983) to NHANES III. This is a cross-sectional study of spirometries of 1,106 non-Hispanic Caucasian American adults, including 234 subjects with obstructive and 228 subjects with restrictive spirometric 'abnormalities'. A weighted Kappa statistic was used to evaluate the level of agreement between NHANES III and other commonly used reference standards. The level of agreement in assessing the presence of an 'abnormality' was poor to moderate-values of Kappa statistic ranged from 0.13 to 0.46. There was however, good to very good level of agreement in assessing the severity of the 'abnormality'-values of Kappa statistic ranged from 0.61 to 0.91. This study better quantifies the well-known differences in the interpretation of spirometric 'abnormalities' as a consequence of the recommended change of reference standard to NHANES III, which in turn may cause confusion among patients and their treating physicians.

Association of excess weight and degree of airway responsiveness in asthmatics and non-asthmatics.

It is unclear whether obesity is associated with increasing degree of airway responsiveness in asthmatics. In this study, methacholine challenge test results of 1,725 subjects with respiratory symptoms were reviewed. Obesity was associated with asthma with an odds ratio of 1.72 (95% C.I. 1.36, 2.17). Although there was a significant difference in the degree of airway responsiveness between various body mass index categories of non-asthmatics (p = 0.01), no significant difference was noted among asthmatics (p = 0.93). A weakly significant interaction between asthma status and body mass index on the degree of airway responsiveness was noted (p = 0.08).

Obesity is associated with bronchial hyper-responsiveness in women.

The study's objective was to compare the bronchial hyper-responsiveness (BHR) between those with normal and increased weight and evaluate if the association was sex-specific. In this cross-sectional review of methacholine challenge test results of 1,141 adults for evaluation of respiratory symptoms, logistic regression analysis was conducted to adjust for covariates. When compared to normal weight, overweight or obese women showed a higher prevalence of symptomatic BHR with odds ratios of 1.63 (95% C.I. 1.16-2.29). This association was not seen in men, with a significant sex-specific interaction. This study shows a sex-specific association between symptomatic BHR and overweight or obese status.