Environmental management of asthma in clinical practice: Results from the 2012 National Ambulatory Medical Care Survey

Background

The National Asthma Education and Prevention Program guidelines emphasize environmental control as an integral part of asthma management; however, limited national-level data exist on how clinicians implement environmental control recommendations.

Objective

We analyzed data on clinicians' self-reported use of recommended environmental control practices in a nationally representative sample (n = 1645) of primary care physicians, asthma specialists, and advanced practice providers from the National Asthma Survey of Physicians, a supplemental questionnaire to the 2012 National Ambulatory Medical Care Survey.

Methods

We examined clinician and practice characteristics as well as clinicians' decisions and strategies regarding environmental trigger assessment and environmental control across provider groups. Regression modeling was used to identify clinician and practice characteristics associated with implementation of guideline recommendations.

Results

A higher percentage of specialists assessed asthma triggers at home, school, and/or work than primary care or advanced practice providers (almost always: 53.6% vs 29.4% and 23.7%, respectively, P < .001). Almost all clinicians (>93%) recommended avoidance of secondhand tobacco smoke, whereas recommendations regarding cooking appliances (eg, proper ventilation) were infrequent. Although assessment and recommendation practices differed between clinician groups, modeling results showed that clinicians who reported almost always assessing asthma control were 5- to 6-fold more likely to assess environmental asthma triggers. Use of asthma action plans was also strongly associated with implementation of environmental control recommendations.

Conclusions

Environmental assessment and recommendations to patients varied among asthma care providers. High adherence to other key guideline components, such as assessing asthma control, was associated with environmental assessment and recommendation practices on environmental control.

Serum antioxidant vitamins and respiratory morbidity and mortality: a pooled analysis

BACKGROUND

Oxidative stress plays a key role in the pathogenesis of respiratory diseases; however, studies on antioxidant vitamins and respiratory outcomes have been conflicting. We evaluated whether lower serum levels of vitamins A, C, D, and E are associated with respiratory morbidity and mortality in the U.S. adult population.

METHODS

We conducted a pooled analysis of data from the 1988-1994 and 1999-2006 National Health and Nutrition Examination Survey (participants aged ≥ 20 years). We estimated covariate-adjusted odds ratios (aOR) per interquartile decrease in each serum vitamin level to quantify associations with respiratory morbidity, and covariate-adjusted hazard ratios (aHR) to quantify associations with respiratory mortality assessed prospectively through 2015. Vitamin supplementation and smoking were evaluated as potential effect modifiers.

RESULTS

Lower serum vitamin C increased the odds of wheeze among all participants (overall aOR: 1.08, 95% CI: 1.01-1.16). Among smokers, lower serum α-tocopherol vitamin E increased the odds of wheeze (aOR: 1.11, 95% CI: 1.04-1.19) and chronic bronchitis/emphysema (aOR: 1.13, 95% CI: 1.03-1.24). Conversely, lower serum γ-tocopherol vitamin E was associated with lower odds of wheeze and chronic bronchitis/emphysema (overall aORs: 0.85, 95% CI: 0.79-0.92 and 0.85, 95% CI: 0.76-0.95, respectively). Lower serum vitamin C was associated with increased chronic lower respiratory disease (CLRD) mortality in all participants (overall aHR: 1.27, 95% CI: 1.07-1.51), whereas lower serum 25-hydroxyvitamin D (25-OHD) tended to increase mortality from CLRD and influenza/pneumonia among smokers (aHR range: 1.33-1.75). Mortality from influenza/ pneumonia increased with decreasing serum vitamin A levels in all participants (overall aHR: 1.21, 95% CI: 0.99-1.48). In pooled analysis, vitamin C deficiency and 25-OHD insufficiency were associated with mortality from influenza/pneumonia, increasing mortality risk up to twofold.

CONCLUSIONS

Our analysis of nationally representative data on over 34,000 participants showed that lower serum levels of vitamins A, C, D, and α-tocopherol vitamin E are associated with increased respiratory morbidity and/or mortality in U.S. adults. The results underscore the importance of antioxidant vitamins in respiratory health.

Use of National Asthma Guidelines by Allergists and Pulmonologists: A National Survey

BACKGROUND

Little is known about specialist-specific variations in guideline agreement and adoption.

OBJECTIVE

To assess similarities and differences between allergists and pulmonologists in adherence to cornerstone components of the National Asthma Education and Prevention Program's Third Expert Panel Report.

METHODS

Self-reported guideline agreement, self-efficacy, and adherence were assessed in allergists (n = 134) and pulmonologists (n = 99) in the 2012 National Asthma Survey of Physicians. Multivariate models were used to assess if physician and practice characteristics explained bivariate associations between specialty and "almost always" adhering to recommendations (ie, ≥75% of the time).

RESULTS

Allergists and pulmonologists reported high guideline self-efficacy and moderate guideline agreement. Both groups "almost always" assessed asthma control (66.2%, standard error [SE] 4.3), assessed school/work asthma triggers (71.3%, SE, 3.9), and endorsed inhaled corticosteroids use (95.5%, SE 2.0). Repeated assessment of the inhaler technique, use of asthma action/treatment plans, and spirometry were lower (39.7%, SE 4.0; 30.6%, SE 3.6; 44.7%, SE 4.1, respectively). Compared with pulmonologists, more allergists almost always performed spirometry (56.6% vs 38.6%, P = .06), asked about nighttime awakening (91.9% vs 76.5%, P = .03) and emergency department visits (92.2% vs 76.5%, P = .03), assessed home triggers (70.5% vs 52.6%, P = .06), and performed allergy testing (61.8% vs 21.3%, P < .001). In multivariate analyses, practice-specific characteristics explained differences except for allergy testing.

CONCLUSIONS

Overall, allergists and pulmonologists adhere to the asthma guidelines with notable exceptions, including asthma action plan use and inhaler technique assessment. Recommendations with low implementation offer opportunities for further exploration and could serve as targets for increasing guideline uptake.

Primary care clinician adherence with asthma guidelines: the National Asthma Survey of Physicians

Background and objectives: Although primary care clinicians provide >60% of U.S. asthma care, no nationally representative study has examined variation in adherence among primary care groups to four cornerstone domains of the Expert Panel Report-3 asthma guidelines: assessment/monitoring, patient education, environmental assessment, and medications. We used the 2012 National Asthma Survey of Physicians: National Ambulatory Medical Care Survey to compare adherence by family/general medicine practitioners (FM/GM), internists, pediatricians and Community Health Center mid-level clinicians (CHC). Methods: Adherence was self-reported (n = 1355 clinicians). Adjusted odds of almost always adhering to each recommendation (≥75% of the time) were estimated controlling for clinician/practice characteristics, and agreement and self-efficacy with guideline recommendations. Results: A higher percentage of pediatricians adhered to most assessment/monitoring recommendations compared to FM/GM and other groups (e.g. 71.6% [SE 4.0] almost always assessed daytime symptoms versus 50.6% [SE 5.1]-51.1% [SE 5.8], t-test p < 0.05) but low percentages from all groups almost always performed spirometry (6.8% [SE 2.0]-16.8% [SE 4.7]). Pediatricians were more likely to provide asthma action/treatment plans than FM/GM and internists. Internists were more likely to assess school/work triggers than pediatricians and CHC (environmental assessment). All groups prescribed inhaled corticosteroids for daily control (84.0% [SE 3.7]-90.7% [SE 2.5]) (medications). In adjusted analyses, pediatric specialty, high self-efficacy and frequent specialist referral were associated with high adherence. Conclusions: Pediatricians were more likely to report high adherence than other clinicians. Self- efficacy and frequent referral were also associated with adherence. Adherence was higher for history-taking recommendations and lower for recommendations involving patient education, equipment and expertise.

Respiratory disease in United States farmers

OBJECTIVES

Farmers may be at increased risk for adverse respiratory outcomes compared with the general population due to their regular exposures to dusts, animals and chemicals. However, early life farm exposures to microbial agents may result in reduced risk. Understanding respiratory disease risk among farmers and identifying differences between farmers and other populations may lead to better understanding of the contribution of environmental exposures to respiratory disease risk in the general population.

METHODS

We compared the prevalence of self-reported respiratory outcomes in 43548 participants from the Agricultural Health Study (AHS), a prospective cohort of farmers and their spouses from Iowa and North Carolina, with data from adult participants in the National Health and Nutrition Examination Survey (NHANES) over the same period (2005-2010).

RESULTS

AHS participants had lower prevalences of respiratory diseases (asthma, adult-onset asthma, chronic bronchitis and emphysema), but higher prevalences of current respiratory symptoms (wheeze, cough and phlegm) even after controlling for smoking, body mass index and population characteristics. The overall prevalence of asthma in the AHS (7.2%, 95% CI 6.9 to 7.4) was 52% of that in NHANES (13.8%, 95% CI 13.3 to 14.3), although the prevalence of adult-onset asthma among men did not differ (3.6% for AHS, 3.7% for NHANES). Conversely, many respiratory symptoms were more common in the AHS than NHANES, particularly among men.

CONCLUSIONS

These findings suggest that farmers and their spouses have lower risk for adult-onset respiratory diseases compared with the general population, and potentially higher respiratory irritation as evidenced by increased respiratory symptoms.

Characteristics of allergic sensitization among asthmatic adults older than 55 years: results from the National Health and Nutrition Examination Survey, 2005-2006

BACKGROUND

Approximately 60% to 80% of children and young adults with asthma are sensitized to at least one allergen. In contrast, previous studies from specific subpopulations of older patients with asthma suggest that allergic sensitization is significantly lower in this age group. The prevalence and patterns of IgE-mediated sensitization have not been compared among a broad population of younger and older patients with asthma.

OBJECTIVE

To determine the prevalence and patterns of IgE-mediated sensitization among a broad population of younger and older patients with asthma.

METHODS

Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 2005-2006 to compare IgE-mediated sensitization rates between younger (20-40 years) and older (≥55 years) patients with current asthma. Atopy was defined as a detectable serum IgE to at least 1 allergen in a panel of 19 allergens. The associations among sensitization, current asthma, and asthma control measures (health care use and symptoms) were examined by logistic regression.

RESULTS

In a group of 2,573 patients, either 20 to 40 years of age or 55 years or older, 108 (6.7%) and 43 (4.5%) patients with current asthma were identified, respectively. Allergic sensitization rates among the adults with asthma differed only moderately and not statistically significantly between the age groups; 75.4% of the younger and 65.2% of the older asthmatic patients were sensitized to at least 1 allergen. The association between sensitization and markers of asthma control did not appear to differ among the age groups.

CONCLUSION

Allergic sensitization in older patients with asthma may be more common than previously reported.