Su-Jau Yang

Overweight/Obesity and Risk of Seasonal Asthma Exacerbations

BACKGROUND Obesity is associated with an increased risk for asthma exacerbations, but whether this risk is related to the season of exacerbation is not known. OBJECTIVE To determine the relationship of increased body mass index (BMI) to the season of asthma exacerbation. METHODS Study subjects were adult (aged 18-65 years) and children (aged 5-17 years) health plan members with persistent asthma in 2008 for whom a BMI measurement was available. BMI categories were normal (<25 kg/m(2)), overweight (25-29.9 kg/m(2)), and obese (≥30 kg/m(2)). Exacerbations were defined as oral corticosteroid dispensings linked to an asthma encounter in the spring, summer, fall, or winter of 2009. RESULTS The cohort included 17,316 adults and 10,700 children. There was a significant (P < .05) linear increase with BMI category in the proportion of adults with exacerbations in every season and in the proportion of children with exacerbations during fall and winter. Relationships of overweight or obesity (vs normal weight) to fall and winter exacerbations remained significant in both adults and children after adjustment for sex and education. In a generalized estimating equation model, both BMI status and season (spring, fall, and winter) were related to exacerbations. Moreover, we noted a significant interaction in adults (P = .03) but not children (P = .97) of the BMI-exacerbation association by season (fall-winter vs spring-summer). CONCLUSION Higher BMI values increased the risk for asthma exacerbations in adults and children with persistent asthma, particularly for fall-winter exacerbations in adults. Potential mechanisms for these findings, including vitamin D status, viral infections, and corticosteroid responsiveness, merit further study.

The Relationship of Asthma Impairment Determined by Psychometric Tools to Future Asthma Exacerbations

BACKGROUND Impairment and risk are considered separate domains of asthma control, but relationships between them are not completely understood. We compared three validated questionnaires reflecting asthma impairment in their ability to predict future exacerbations. METHODS Two thousand six hundred eighty patients with persistent asthma completed a survey that included the Asthma Control Test (ACT), mini-Asthma Quality of Life Questionnaire (mAQLQ), and Asthma Impact Survey (AIS-6), as well as a history of exacerbations in the prior 12 months. An exploratory factor analysis was performed using the questions of the three tools, and individual patient factor scores were calculated. Independent relationships between predictors (tools and factors) and exacerbations the following year captured from administrative data were evaluated. RESULTS Each tool was significantly related (P < .0001) to future exacerbations above and beyond the risk conferred by prior exacerbations (relative risk [RR] = 1.3). When prior exacerbations were included in the model, the three impairment tools provided similar and overlapping information, such that only the mAQLQ entered the model (RR = 1.3; 95% CI, 1.1-1.5). Factor analysis revealed three factors (symptoms, activity, and bother) that were each significantly associated (P < .0001) with future asthma exacerbations. However, only the activity factor was independently related to future exacerbations. CONCLUSIONS Asthma impairment is significantly related to the risk of future exacerbations, but the ACT, mAQLQ, and AIS-6 do not provide independent information from each other in this regard. Interference with activities is the primary subjective component of asthma impairment that is related to the risk of future exacerbations.

The burden of rhinitis in a managed care organization

BACKGROUND Rhinitis is a common health condition, but the extent of the burden in managed care organizations (MCOs) has not been well described. OBJECTIVE To compare medical utilization in a large MCO of patients (1) with vs without rhinitis and (2) with allergic (AR) vs nonallergic (NAR) rhinitis. METHODS Patients 4 years and older with 1 or more encounters with an International Classification of Diseases, Ninth Revision, code for rhinitis and patients treated for rhinitis but without a rhinitis encounter (rhinitis treatment-only group) were identified. Patients seen in allergy departments for rhinitis were categorized as having AR or NAR. RESULTS Of 1,726,084 patients continuously enrolled for all 4 study years, 29% had 1 or more encounters for rhinitis (15%) or were treated for rhinitis (14%). Compared with patients without rhinitis, those with rhinitis encounters were significantly more likely to have encounters for asthma (odds ratio [OR], 2.7), acute sinusitis (OR, 4.4), chronic sinusitis (OR, 15.2), conjunctivitis (OR, 1.5), acute otitis media (OR, 1.9), chronic otitis media (OR, 4.3), sleep apnea (OR, 3.4), and fatigue (OR, 2.0). Results for rhinitis treatment-only patients (n = 242,565) were generally similar to those for rhinitis encounter patients. NAR was diagnosed in 21% of patients, who were significantly more likely than patients with AR to undergo sinus radiology and nasal surgery; to receive diagnoses of sinusitis, otitis media, sleep apnea, and fatigue; and to receive medications for nonrespiratory conditions (P < .001). CONCLUSIONS Rhinitis was common in this large MCO. Patients with rhinitis, especially NAR, had significantly more respiratory and nonrespiratory comorbid conditions than did patients without rhinitis.

Prospective Study on the Relationship of Obesity to Asthma Impairment and Risk

BACKGROUND Although studies consistently show an association between obesity and increased asthma incidence, the role of obesity in asthma control is less clear. OBJECTIVE The objective of this study was to evaluate the association between baseline body mass index (BMI) and measures of subsequent asthma control in a large real-world cohort of adults with persistent asthma. METHODS In Kaiser Permanente Southern California (KPSC), a large managed care organization, we identified adults with persistent asthma in 2006, continuous health plan enrollment in 2007 and 2008, and a BMI measurement in 2006 or 2007. Each patients last BMI measure in 2006 or 2007 was categorized into a BMI group: normal (<25 kg/m(2)), overweight (25-29.9 kg/m(2)), or obese (≥30 kg/m(2)). Asthma control outcomes in 2008 included asthma hospitalizations or emergency department visits (EDHO), oral corticosteroid dispensings linked to an asthma encounter (OCS), and dispensing of ≥7 short-acting beta-agonist canisters (SABA7). Multivariable analyses were conducted to assess the relationships of BMI categories with the risk of the asthma control outcomes after controlling for potential confounders. RESULTS In the 10,233 eligible adults-after adjusting for potential demographic, comorbidity, and prior utilization confounders-we found an increased relative risk (RR) of EDHO in overweight and obese (RR 1.40, 95% CI 1.10-1.78) individuals. Only obesity was associated in adjusted analyses with a significant increased relative risk of SABA7 (RR 1.27, 95% CI 1.15-1.40). CONCLUSIONS Elevated BMI, particularly obesity, is associated with subsequent poor asthma control, especially in the risk domain (exacerbations). These findings further support the importance of facilitating weight loss in overweight and obese adults with asthma.

Change in Asthma Control Over Time: Predictors and Outcomes

BACKGROUND Maintenance of asthma control over time is a clear goal of national asthma guidelines, but few studies have addressed the natural history of asthma control over time. OBJECTIVE To assess the impairment domain of asthma control over time in patients with persistent asthma and to determine predictors and consequences of controlled and uncontrolled asthma over time. METHODS Patients 18-56 years old with persistent asthma who completed baseline (November 2007) and follow-up asthma surveys (April, July, October 2008) were included in the study. The survey included the Asthma Control Test as well as questions regarding other patient and asthma characteristics. Health care utilization (pharmacy and exacerbations) for 2008 was obtained from administrative data. RESULTS The baseline and first follow-up surveys were completed by 1267 patients, and all 4 surveys were completed by 782 patients. Patients with well-controlled asthma at baseline were significantly more likely (P < .0001) to have well-controlled asthma over the following year (76.2%-80.4%) than patients with uncontrolled asthma at baseline (33.5%-36.9%). Patients whose asthma control improved over the first several months of follow-up experienced significantly (P < .05) fewer exacerbations over the subsequent year than patients with initially uncontrolled asthma who did not improve. CONCLUSION Degree of asthma control at one point in time is strongly related to the achievement or maintenance of control and to asthma exacerbations over time. Patients with uncontrolled asthma, especially very poorly controlled asthma, should receive intensive management and follow-up in an attempt to achieve well-controlled asthma over time.

C-C4-03: Teen Tobacco Use and Depression in Primary Care

Background/Aims: Tobacco use is the number one cause of preventable morbidity and death in the nation. Despite the ever growing list of harmful effects associated with smoking, tobacco use is common among children and adolescents and approximately half who try smoking will progress to regular use and dependence. Of concern, the great progress achieved between 1997 and 2003 in reducing teen smoking has stalled with overall rates near 20%. There is only limited evidence of the effectiveness of smoking cessation interventions in teen populations, and the low probability that adolescents will stop smoking on their own highlights the importance of prevention and early detection. Depressive disorders occur in approximately one in five youth by age 18 and are associated with a broad range of negative effects on health, as well as academic and social functioning. Methods: We examined the association of smoking and depression in a large, diverse population of teens seeking primary care from 7 health care organizations in Los Angeles and Washington, D.C. Subjects and their parents were recruited from January, 2005 through March, 2006 to participate in the Teen Depression Awareness Project (TDAP). Among the 4722 teens eligible and interested in participation, 4529 completed a structured telephone interview which assessed depression using the Diagnostic Interview Schedule for Children and queried smoking status. Results: Smoking prevalence varied significantly among teens who scored “non-depressed,” “sub-threshold depressed,” and “depressed” (3.2%, 9.3%, and 15%, respectively). Multivariable analyses controlling for gender, race/ethnicity, age, BMI percentile, and health care site found that compared with non-depressed teens, teens with sub-threshold depression were almost three times as likely to smoke (OR=2.9, CI=1.6, 5.2) and depressed teens were more than 5 times as likely to smoke (OR=5.4, CI=3.4,8.7). Among teens who smoked, 25% suffered depressive symptoms. Conclusions: Primary care visits represent an important opportunity to identify teens at risk for and from depression and smoking. Effective treatments for smoking and depression need to address the co-occurrence and interaction of these serious threats to adolescent health.