A Randomized Trial of a Self-Regulation Intervention for Women With Asthma

CHEST

Original Research ASTHMA

A Randomized Trial of a Self-Regulation Intervention for Women With Asthma* Noreen M. Clark, PhD; Z. Molly Gong, MD; Si Jian Wang, MPH; Xinhong Lin, PhD; William F. Bria, MD, FCCP; and Timothy R. Johnson, MD

Background: Women with asthma have greater mortality and morbidity than men in the United States. To date, there has been no rigorous evaluation of an intervention focused on the particular problems in asthma management faced by women. This study was a randomized clinical trial of a self-regulation, telephone counseling intervention emphasizing women’s concerns, and sex and gender role factors in their management of asthma. Methods: A total of 808 women with diagnosed asthma were randomly assigned to the intervention group or a usual-care control group, including conventional asthma education. Interviews and medical record data were collected to assess psychosocial factors, and the behavioral factors of functioning, quality of life, symptoms, and health-care use at baseline and the subsequent 1 year. Generalized estimating equations, identity link, logit link, and log link were employed to analyze the data. Results: Compared to control subjects, the women receiving treatment had greater annual reductions in the average number of nights with asthma symptoms (p ⴝ 0.04), days of missed work/school (p ⴝ 0.03), emergency department visits (p ⴝ 0.04), unscheduled office visits (p ⴝ 0.01), and scheduled office visits (p ⴝ 0.04). They had greater recognition of asthma symptoms during the menstrual cycle (p ⴝ 0.0003), had decreased asthma symptoms with sexual activity (p ⴝ 0.008), and had greater improvement in quality of life (p ⴝ 0.0005), self-regulation (p ⴝ 0.03), and self-confidence to manage asthma (p ⴝ 0.001). Conclusion: The intervention improved women’s clinical status, functioning, quality of life, and health-care use. A program with a focus on asthma management problems particular to women can significantly assist female asthma patients. (CHEST 2007; 132:88 –97) Key words: asthma; chronic conditions; management by patients; outcomes; women’s health Abbreviations: BMI ⫽ body mass index; ED ⫽ emergency department; ERT ⫽ estrogen replacement therapy; GEE ⫽ generalized estimating equation; NAEPP ⫽ National Asthma Education and Prevention Program; PMS ⫽ premenstrual symptoms; UMHS ⫽ University of Michigan Health System

9% of women in the United States have O ver asthma compared to 5% of men. Asthma has a differential impact on women. During the last decade, the increase in the asthma mortality rate for men was 34%, whereas for women it was 59%. *From the Center for Managing Chronic Disease (Drs. Clark and Gong), and the Department of Biostatistics (Mr. Wang), School of Public Health, and the Department of Obstetrics and Gynecology (Dr. Johnson), School of Medicine, University of Michigan, Ann Arbor, MI; the Department of Biostatistics (Dr. Lin), School of Public Health, Harvard University, Cambridge, MA; and Shriners Hospitals for Children (Dr. Bria), Tampa, FL. The research was supported by grant 1 R18 HL60884 – 01 from the Division of Lung Diseases of the National Heart, Lung, and Blood Institute. 88

Women consistently have higher rates of clinic visits, hospital admissions, and hospital readmissions for asthma than men.1–3 Reports in the literature are beginning to describe differences in etiology, natural The authors have reported to the ACCP that no significant conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article. Manuscript received November 2, 2006; revision accepted March 6, 2007. Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (www.chestjournal. org/misc/reprints.shtml). Correspondence to: Noreen Clark, PhD, University of Michigan, School of Public Health, 109 S Observatory, Ann Arbor, MI 48109; e-mail: [email protected] DOI: 10.1378/chest.06-2539 Original Research

history, and asthma management needs that may be attributable to the sex or gender role of the patient. Studies4 –7 have suggested that asthma symptoms may worsen for as many as 30 to 40% of women during menses. Cough and breathlessness are more severe in women with menstruation-linked asthma, and these patients may exhibit a decrease in their peak expiratory flow rate.6,8 Women with menstruation-linked asthma have more visits to the emergency department (ED) and more hospitalizations, and they require extra medication during the premenstrual and/or menstrual weeks.4,7 Women with asthma who are receiving estrogen replacement therapy (ERT) have an increased risk of asthma symptoms9,10 and a decreased peak flow requiring more therapy with inhaled bronchodilators.11,12 One third of pregnant women with asthma experience a worsening of asthma symptoms during pregnancy.13 Within most cultures, women have the primary responsibility for child care and household management. Hence, they are exposed to many potential asthma triggers.14,15 Allergens including dust mites, fungi, molds, and yeasts may be problematic for some women.14 –16 Sensitizing agents such as household sprays, cleaning materials, perfumes, scented personal care products, cosmetics, and other products have been reported as triggers.17 To date, no rigorously evaluated intervention has focused on the particular problems that women face in the management of asthma. This randomized clinical trial evaluated a self-regulation intervention that emphasized women’s concerns and sex and gender role factors in the management of asthma. The hypotheses were that women in the intervention group when compared to women in the control group would exhibit greater reductions in the following: (1) the number of days and nights with symptoms; (2) the number of days of missed work or school; (3) the number of office visits, ED visits, and hospitalizations for asthma; and (4) the number of management problems related to sex and gender roles. Further, improvements in quality of life, self-regulation, and self-confidence to perform asthma management tasks were expected in these women. Materials and Methods Study Design and Sample A random controlled study design was employed using two groups of female patients at the University of Michigan Health System (UMHS) who met the study criteria. Because a range of factors was expected to influence outcomes beyond asthma severity, the decision was made not to match women in the two groups with respect to disease severity. Patients were randomly assigned to an intervention group or a usual-care group. Usual care within the UMHS comprises treatment based on National Asthma Education Prevenwww.chestjournal.org

tion Program (NAEPP) guidelines for the diagnosis and management of asthma,18 as well as telephone follow-up for purposes of patient monitoring. Asthma education is provided at the time of clinic visit. This education is similar to that found in most health-care institutions and does not emphasize sex and gender issues in asthma management. Study procedures were approved by the institutional review board of the University of Michigan Medical School. No adverse events were reported during the course of the study. The criteria for recruitment of all study participants were as follows: (1) ⱖ 18 years of age; (2) diagnosis of asthma by a UMHS physician, based on NAEPP guidelines for the diagnosis and management of asthma18; (3) the presence of active symptoms in the past 12 months (including any from among persistent cough, chest tightness, chest heaviness, shortness of breath, wheezing, and difficulty sleeping because of breathing problems); (4) having been enrolled as a patient in one of the participating asthma-related clinics; (5) no extenuating medical or mental conditions (ie, terminal illness or dementia); and (6) access to a telephone. The UM Data Warehouse of the University of Michigan Administrative Information Services provided a list of women who met the study criteria. Figure 1 presents the participation trajectory of 2,336 women who were sent study invitation letters and response postcards during the 3.5-year recruitment period. All women who did not return the postcard were contacted by telephone. Consent forms were mailed to a total of 997 women who agreed to participate when telephone contact was made. Ultimately, 808 respondents who returned the completed consent forms by mail provided baseline data. These women were randomized into either the treatment group to receive the self-regulation intervention or to the usual-care control group. Participants’ physicians were blind to the assignment of their patients in this study. The failure of women to enroll in the study was attributable to problematic addresses or phone numbers or having moved their residence out of the study area (n ⫽ 774), death from all causes (n ⫽ 49), lack of interest (n ⫽ 307), belief that one did not have asthma (n ⫽ 159), and no stated reason or did not fit study criteria (n ⫽ 232). The Intervention The intervention is a multiple-component behavioral education program, known as “Women Breathe Free,” that is delivered by a nurse health educator through telephone counseling. It is based on social cognitive theory.19 Women in the intervention group were introduced to a self-regulatory, problem-solving process20 to be performed in accordance with the patient’s therapeutic plan. An important component of the intervention was that each participant’s developmental phase of self-regulation was determined at baseline,21,22 and telephone counseling was then tailored to that particular level of self-regulation. Salient sex role-related and gender role-related asthma problems were also assessed, as were the particular concerns of the woman in managing her condition. Participants were encouraged to use the program process to study the range of factors affecting their asthma, including the potential effects of social role and/or hormonal factors (eg, menses, use of ERT, or premenstrual symptoms [PMS]). Each woman selected a focus for her problem solving in light of the clinical recommendations of her physician. The women were mailed an educational kit containing a workbook, a list of sex-related and gender-related asthma concerns, specially designed diaries, and a peak flowmeter with an instructional videotape. During the first 45-min counseling session, women were instructed in the first step of the Women Breathe Free approach, and were asked to use the peak flowmeter and the personalized graph diary as observational tools to monitor their symptoms and behaviors. They were also asked to observe potential influences on peak flow rate and symptoms, as well as the effects of changes in medicine use, and possible associations between symptoms and phases of the menstrual cycle, or use of CHEST / 132 / 1 / JULY, 2007

89

Invitation Letters 2336

No phone contact possible 873

Contacted by phone 1463

Agreed to participate 997

Refused 466

Consented and provided baseline 808

RANDOMIZATION Intervention 424

Control 384

Attrition 113

Attrition 87

Intention to Treat Group:

Completed Partial participation program in program but stayed in study 257

34

Did not complete study 20

Follow up intervention group 311

Follow up control group 297

Figure 1. Study participation.

estrogen replacement or oral contraceptives, for example. During the observation month, they received weekly postcards to remind them of participation in diary keeping and peak flow monitoring, and a mid-month phone call from the health educator to discuss any concerns they might have with observation or other elements of the program. Following the month of self-observation, the women in the program received a total of four 30-min to 45-min telephone counseling interventions at 2-week intervals. Each subsequent session focused on sequentially teaching the women the steps of self-regulatory problem-solving processes, including the problem addressed, the management goal set, and the step-by-step action 90

plan. A checklist was mailed in 2 months after the fifth session, and a final “booster” telephone contact was made 6 months after the fifth session. Table 1 summarizes the program protocol. Measures and Data Collection Self-reported recall data were collected by telephone interview at baseline, prior to randomization, and 1 year later. Data collectors were blind to the assignment of the woman to the study arms. Several measures were used for data collection. Original Research

Table 1—Women Breathe Free Program Sessions Health Educator’s Objectives (Counseling Geared to Woman’s Level of Self-Regulation)

Session I (45–60 min)

Interim to sessions I and II (10 min)

II (1 h)

III (1 h)

IV (30 min)

V (20–30 min)

Follow-up contacts

1. Confirmed use of peak flowmeter; 2. Confirmed ability to use diary; 3. Confirmed ability to observe and record symptoms, medication use, and daily activities including leisure time physical and social activities; 4. Discussed potential gender-related influences on asthma; and 5. Discussed potential asthma self-management problems to address and begin to explore gender-related factors (all counseling based on woman’s level of self-regulation) 6. Provided support through three postcard reminders mailed on a weekly basis during the first month to stimulate self-observation processes; and 7. Encouraged full patient participation through phone contact made weekly to discuss any concerns participants may have with the observation process and program elements 1. Reviewed month of peak flowmeter use and symptom and daily activities; 2. Linked data with potential external and internal factors identified, including sociocultural role and hormonal factors; 3. Reviewed medication plan provided by physician; and 4. Helped women select an asthma self-management problem to address and explore gender-related issues 1. Reviewed 2 wk of peak flowmeter use and symptoms, medication use, and physical and social activity data; 2. Linked data with potential external and internal factors including gender-related issues; 3. Confirmed the problem area to address; 4. Identified a management goal associated with changes in symptoms and peak flowmeter readings toward which to work and to ensure it meets women’s personal priorities; and 5. Developed a step-by-step plan to achieve goal with attention to potential weight- and gender-related factors 1. Reviewed progress toward goal; 2. Explored reactions (eg, outcome expectations and feelings of self-efficacy); 3. Adjusted plan as needed as above; and 4. Selected a personal reward to mark (celebrate) when the goal is reached 1. Reviewed progress; 2. Explored reactions; 3. Considered next steps (eg, refine plan or choose new problem); and 4. Discussed reward and benchmarks of progress 1. Monthly follow-up checklist was mailed to each participant after session V, followed by a telephone call in which feedback was offered by telephone or by mail addressing any concerns the participants might have regarding their action plans; and 2. A final “booster” telephone contact was made 6 mo after session V

Frequencies of daytime and nighttime symptoms are two of the criteria used in the NAEPP guidelines18 to classify severity of asthma. Considering the seasonality of asthma, interview items tapped the number of days and nights by month and by season that the woman had asthma symptoms and had missed work or school because of asthma in the past 12 consecutive months. Questionnaire items mimicked a clinician’s queries of patients during the clinical encounter and have been used in previous studies.23,24 Respondent self-reported ED visits and hospitalizations have been shown to correlate significantly with records of health-care www.chestjournal.org

Goal for Patient

Time

Self-observed for 1 mo (mail copy of diary data back to nurse health educator)

1 wk from instructional kit being mailed to the participant

Continued self-observation

Weekly phone contacts and postcard reminders are made and sent for 3 wk

Identified a potential asthma management problem, and explored weight and gender role and other relevant factors

Counseling call 1 mo subsequent to the first call of session I, and postcard sent 1 wk later

Developed a plan for addressing the problem area and reaching goal; carried out steps of the plan

Counseling call 2 wk subsequent to session II, postcard 1 wk later

Assessed progress, finetuned plan, and continued toward problem resolution

Counseling call 2 wk subsequent to session III and postcard sent 1 wk later

Achieved goal as appropriate, applied problem-solving process to new or different management problem

Counseling call 2 wk subsequent to session IV, and postcard sent 1 wk later

institutions and to provide a reliable assessment of these types of health-care use.25 The self-reported recall data of the number of hospitalizations, ED visits, unscheduled urgent visits to a clinic, and scheduled clinic visits for asthma in the past 12 months were assessed through a series of items for the baseline and follow-up periods. To further verify the accuracy and reliability of the self-reports of asthma health-care use, medical record data for asthma ED visits and hospitalizations from the UM Data Warehouse during the corresponding time periods were collected to examine the correlations between the two sources of data. Sex role-related and gender role-related queries were made CHEST / 132 / 1 / JULY, 2007

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that were related to symptoms and menstrual cycle, PMS, birth control pills, ERT, and urinary incontinence. Items were also tapped as asthma problems related to housework (eg, vacuuming, dusting, or cooking), washing or cleaning products, fragrances, cosmetics, and hair products, exposures through child care, and symptoms associated with social and sexual activity. The Mini Asthma Quality of Life Questionnaire of Juniper and colleagues26,27 was used to measure a woman’s quality of life. A scale of self-confidence for asthma management comprised 15 items that had previously been used by the investigators to assess a woman’s perception of her ability to carry out management tasks at home.28 To assess the level or phase of a woman’s self-regulation ability, items from the Zimmerman scale23,24 were used to determine asthma-related practices, including the use of peak flow monitoring. Demographic data were also collected for use as covariates in the statistical models if needed. Statistical Analysis Sample size calculations using health-care use as the primary dependent variable determined that a final sample of 520 was needed to achieve 80% power at the 95% confidence level. A sample of this magnitude would allow testing of other study outcomes with a similar or higher level of confidence. Data from 608 women were available for intent-to-treat analysis at 1 year subsequent to baseline. Descriptive analyses were conducted to examine randomization status (Table 2) and outcome variables (Table 3) at two time points for the groups. Descriptive analyses were then used to examine drop out data. There were no differences in dropouts due to demographic variables, disease severity, and important outcomes between the two groups. Hence, the generalized estimate equation (GEE) method, under the assumption of data missing completely at random, was used to further examine the statistically significant group differences for each outcome vari-

Table 2—Comparisons Between Treatment and Control Groups at Baseline* Variables Age, yr Annual household income ⬍ $20,000 Minority High school education or less Married Employed BMI From specialty clinics Asthma severity Mild intermittent Mild persistent Moderate persistent Severe persistent Total persistent asthma Medicine use Inhaled corticosteroids Oral corticosteroids Inhaled nonsteroidal Antileukotrienes Long-acting bronchodilators Short-acting inhaled bronchodilators Herbal/remedies

Control Group

Treatment Group p Value

48.7 (14.3) 13.8 16.3 32.4 60.3 67.5 29.4 (7.7) 32.0

48.2 (13.1) 13.7 15.8 28.3 64.6 64.8 30.2 (8.4) 34.9

0.72 0.97 0.85 0.21 0.21 0.42 0.15 0.39

56.0 13.5 17.7 12.8 44.0

48.5 16.8 21.5 13.2 51.5

0.10 0.21 0.20 0.45 0.03

58.9 8.3 2.6 32.3 33.3 87.0 58.9

55.2 12.0 2.6 35.6 31.1 90.3 55.2

0.21 0.22 0.99 0.56 0.50 0.13 0.39

*Values are given as the mean (SD) or %, unless otherwise indicated. 92

able. The GEE method allows for the use of all available data at baseline (n ⫽ 808) and follow-up (n ⫽ 608).29 GEE linear regression analysis was used for continuous outcome variables, GEE logistic regression was used for binary variables, and GEE log-linear regression was used for count outcomes.29,30 The GEE methods analyzed the baseline and follow-up data by including an indicator variable (time) for the follow-up, an indicator variable (treatment) for the intervention group and their interaction (treatment ⫻ time), and baseline covariates including demographics and other variables that were significant in initial models. In all final models, age, body mass index (BMI), and severity according to NAEPP classification at baseline were adjusted. The PROC GENMOD procedure (SAS; SAS Institute; Cary, NC) was used for fitting the models. For all models, an unstructured covariance matrix was used to account for the longitudinal nature of the data.30 Hospitalization was an exceptional variable. Most women (90% at baseline and 94% at follow-up) reported no hospital admissions. Poisson regression models are not appropriate when the frequency of zero observation is very high.29,30 Therefore, we have reported findings for hospitalizations using the subgroup of women who had at least one hospitalization at baseline. Similar models were fitted for comparisons of data on hospitalization and ED visits from two sources for the subgroup of women who had both medical record and self-reported data.

Results Randomization Status Table 2 shows that there were no statistically significant differences between the intervention and control groups at baseline for any demographic variable, for the percentage of women from specialty clinics or for medication use, and for the asthma severity classification based on nighttime symptoms when comparing the four categories of asthma severity (ie, mild intermittent, mild, moderate, and severe persistent) separately. As noted, when all women reporting persistent asthma were compared to those reporting mild intermittent asthma, the intervention group had significantly more women with persistent asthma than did the control group (51.5% vs 44.0%, respectively; p ⫽ 0.03). Description of Group Outcomes Table 3 describes group means with SDs at two time points, and differences in means between follow-up and baseline for all outcome variables. Symptoms and Health-Care Use Table 4 shows that at follow-up the overall reduction in the average number of nights in a month when women in the treatment group experienced symptoms was significantly greater than the reductions among control group women. There were no treatment or control differences related to the number of days with asthma symptoms. Original Research

Table 3—Mean/Frequency and Difference Between Baseline and Follow-up* Outcome Variables Symptoms Yearly average No. of nights with nighttime symptoms per month C T Yearly average No. of days of daytime symptoms per month C T Health-care use Yearly average No. of ED visits C T Yearly average No. of unscheduled doctor visits C T Yearly average No. of scheduled doctor visits C T Yearly average No. of follow up visits for an attack C T Yearly average No. of hospitalizations C T Absence of quality of life self-regulation self-confidence Yearly average No. of days of missed work per month C T Overall mean quality-of-life score C T Overall mean self-regulation score C T Overall mean self-confidence score C T Gender-specific problems, % Noticed changes during menstrual cycle C T Noticed changes when having PMS C T Bothered by asthma during sexual activities C T Peak flowmeter General use C T Used to monitor last attack C T

Baseline

Follow-up

Follow-up—Baseline

3.9 (6.3) 5.1 (7.2)

3.8 (7.2) 3.7 (6.8)

⫺0.05 (6.7) ⫺1.41 (7.0)

8.5 (8.7) 8.7 (9.2)

7.3 (8.7) 7.9 (9.2)

⫺1.18 (8.7) ⫺0.85 (8.9)

0.5 (1.8) 0.6 (1.6)

0.2 (0.9) 0.2 (1.1)

⫺0.27 (1.5) ⫺0.31 (1.4)

0.8 (1.6) 1.3 (2.8)

0.6 (1.3) 0.6 (1.7)

⫺0.24 (1.5) ⫺0.63 (2.4)

2.1 (2.8) 2.6 (3.9)

1.4 (1.8) 1.6 (2.2)

⫺0.68 (2.4) ⫺1.07 (3.3)

0.9 (1.7) 1.6 (3.2)

0.4 (1.0) 0.9 (2.1)

⫺0.47 (1.4) ⫺0.73 (2.8)

0.2 (1.0) 0.3 (1.2)

0.1 (0.5) 0.2 (0.7)

⫺0.12 (0.8) ⫺0.15 (0.9)

2.3 (6.3) 2.9 (6.3)

3.0 (7.1) 2.3 (6.2)

0.60 (6.7) ⫺0.61 (6.2)

2.1 (0.8) 2.4 (0.9)

2.1 (0.9) 2.1 (0.9)

⫺0.06 (0.9) ⫺0.31 (0.9)

5.8 (2.5) 6.1 (2.3)

5.4 (2.5) 6.1 (2.4)

⫺0.42 (2.5) 0.02 (2.3)

8.0 (1.6) 7.8 (1.6)

7.9 (1.7) 8.2 (1.5)

⫺0.05 (1.7) 0.39 (1.5)

12.2 14.7

8.2 29.3

⫺4.0 14.7

14.2 15.8

9.6 22.1

⫺4.5 6.3

15.1 22.9

14.8 13.7

⫺0.3 ⫺9.2

10.5 15.1

7.8 20.3

⫺2.7 5.3

24.3 27.3

26.3 39.9

2.0 12.6

*Values are given as the mean (SD) or %. C ⫽ control group; T ⫽ treatment group.

Table 5 illustrates that women in the intervention group at follow-up had greater reductions in ED visits and unscheduled and scheduled office visits for asthma compared to women in the control group. When data for the subgroup of women with at least www.chestjournal.org

one hospitalization at baseline were analyzed, the group differences did not reach a statistically significant level. Table 5 indicates that self-reports and hospital record data produced similar results regarding health-care use. CHEST / 132 / 1 / JULY, 2007

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Table 4 —Symptoms Covariates Nighttime symptoms Estimation p Value Daytime symptoms Estimation p Value

Age

Baseline BMI

Time

Treatment

Treatment ⫻ Time

0.01 0.72

0.11 0.0001

⫺0.01 0.99

1.02 0.03

⫺1.19 0.04

0.06 0.002

0.10 0.005

⫺1.35 0.004

0.09 0.89

0.50 0.48

Sex and Gender Table 6 reports outcomes related to sex and gender items in which the results were statistically significant. In 4 of the 17 total relevant items, differences between the treatment and control groups were evident. Women in the treatment group were more likely than control subjects to notice asthma symptoms related to their menstrual cycle and/or when they had PMS. Women in the

treatment group reported a greater reduction in problems with asthma symptoms during sexual activity. They also described a decrease in problems associated with exposures during shopping for household or scented products. No differences were seen in items such as asthma management problems associated with doing housework (eg, vacuuming, dusting, and cooking), child care, and social activities.

Table 5—Health-Care Use and Comparisons of Self-Reported and Medical Records Data

Covariates Health-care use Hospitalization* Estimation p Value ED visits Estimation p Value Unscheduled doctor visits Estimation p Value Scheduled doctor visits Estimation p Value Follow-up visits for an attack Estimation p Value Comparisons of self-reported and medical record data† Hospitalizations Self-report Estimation p Value Medical records Estimation p Value ED visits Self-report‡ Estimation p Value Medical records‡ Estimation p Value

Baseline Persistent Status

Time

Treat

Treatment ⫻ Time

0.01 0.21

⫺1.04 ⬍ 0.0001

⫺0.20 0.87

⫺0.44 0.20

1.27 ⬍ 0.0001

0.04 0.0003

⫺0.54 0.01

0.03 0.88

⫺0.59 0.04

0.002 0.74

1.15 ⬍ 0.0001

0.02 0.001

⫺0.37 0.003

0.30 0.04

⫺0.54 0.01

0.01 ⬍ 0.0001

0.44 ⬍ 0.0001

0.01 0.003

⫺0.40 ⬍ 0.0001

0.13 0.11

⫺0.22 0.04

0.003 0.51

0.92 ⬍ 0.0001

0.02 0.01

⫺0.80 ⬍ 0.0001

0.47 0.001

1.28 0.0002

0.04 0.01

⫺1.79 0.05

0.45 0.19

⫺0.02 0.98

0.03 0.003

⫺1.39 0.07

0.28 0.25

⫺0.10 0.56

Age

0.002 0.75 ⫺0.01 0.06

0.2 0.29 0.03 0.32

0.77 .0001

1.12 ⬍ 0.001

Baseline BMI

0.004 0.99

⫺0.01 0.29

0.94 0.0005

0.05 0.0004

0.05 0.90

0.52 0.05

⫺1.05 0.05

⫺0.03 0.04

0.94 0.01

0.04 0.01

0.92 0.10

0.45 0.30

⫺1.36 0.07

*Only patients with at least one hospital admission at baseline were used in the analysis. †Only patients with medical record data. ‡Time is given as the time from the first follow-up. 94

Original Research

Table 6 —Sex Role-Related and Gender Role-Related Management Problems

Age

Baseline Persistent Status

Baseline BMI

Time

Treat

0.04 0.01

1.07 ⬍ 0.0001

⫺0.003 0.86

⫺0.12 0.56

0.19 0.56

1.16 0.0003

0.03 0.02

1.17 ⬍ 0.0001

⫺0.004 0.78

⫺0.28 0.24

0.09 0.76

0.85 0.01

⫺0.002 0.76

1.36 ⬍ 0.0001

0.02 0.13

0.04 0.81

0.43 0.04

⫺0.86 0.008

0.02 ⬍ 0.0001

0.95 ⬍ 0.0001

0.04 ⬍ 0.0001

0.02 0.88

0.24 0.15

⫺0.37 0.06

Covariates Noticed changes during menstrual cycle Estimation p Value Noticed changes when having PMS Estimation p Value Bothered by asthma during sexual activities Estimation p Value Bothered by asthma during shopping for potential problem products Estimation p Value

Absence, Quality of Life, Self-Regulation, and SelfConfidence At follow-up, compared to control subjects, women in the treatment group had significantly greater improvement in their overall quality of life (note that in the scale of Juniper and colleagues,26,27 a lower score indicates better quality of life); their level of asthma-related self-regulation; and in their confidence to manage asthma (Table 7). Table 7 also indicates that compared to women in the control group, women in the treatment group had a significantly greater overall reduction in the number of days of missed work or school because of asthma. Discussion To the investigators’ knowledge, this is the first study to assess the effect on health outcomes of an asthma self-regulation intervention specifically ad-

Treatment ⫻ Time

dressing the perspective of female patients and their particular sex role-related and gender role-related management challenges. Symptom reduction is an important goal in asthma control, and the findings illustrate that the intervention significantly improved nighttime symptoms for program participants, but it had no significant effect on daytime symptoms. Nighttime symptoms are considered to be a marker of more severe disease, and as more women in the treatment group began the study with more persistent asthma, a reduction in these symptoms is a significant result. It may be that for nighttime symptoms more management was needed by more study women, and this is where the most change could be realized. Better self-regulation may have enabled women in the treatment group to find ways to minimize or avoid symptoms at night. Women in the treatment group experienced less school and work disruption due to asthma subsequent to their participation in the program. These results complement

Table 7—Absence, Quality of Life, Self-Regulation, and Self-Confidence

Covariates Yearly average days missed work/school Estimation p Value Quality of life Estimation p Value Self-regulation Estimation p Value Self-confidence Estimation p Value

www.chestjournal.org

Age

Baseline Persistent Status

Baseline BMI

Time

0.02 0.0002

1.12 ⬍ 0.0001

0.03 0.001

0.18 0.12

0.13 0.36

0.02 ⬍ 0.0001

0.62 ⬍ 0.0001

0.03 ⬍ 0.0001

⫺0.01 0.84

⫺0.01 0.84

0.002 0.001

0.10 ⬍ 0.0001

0.003 0.0042

⫺0.04 0.001

⫺0.03 0.76

0.01 0.38

⫺0.04 0.65

0.02 ⬍ 0.0001

Treatment

0.02 0.25 ⫺0.16 0.14

Treatment ⫻ Time ⫺0.38 0.03 ⫺0.31 0.0005 0.03 0.03 0.42 0.001

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the reduction in nighttime symptoms for program participants and strengthen the argument that the control of symptoms at night can have an important effect on functioning for patients. The positive outcomes for the women in the treatment group regarding ED visits and unscheduled office visits may be related to their improved self-regulation and self-confidence in managing their asthma in light of their physicians’ clinical recommendations. The lack of program benefit regarding hospital admissions may be a function of the program or may be associated with methodologic problems in assessing change when the number of observations is very small. To explore this variable further, we looked at the subset of women who had completed the program and compared them to women who had not completed the program. Hospitalization was 0.2 times less likely in women who completed the intervention sessions compared to women who did not complete the full program. Although this exploratory analysis has problems of self-selection bias, the results may indicate that women do not benefit regarding this outcome unless they complete all counseling sessions. It is also possible, as noted in previous asthma studies,23,24 that significant differences in hospitalizations are found at more distant time points, for example, 18 to 24 months subsequent to baseline. The consideration of sex and gender role factors as they relate to asthma management was one of the unique features of this study. In one fourth of these variables, differences were observed between the treatment and control groups. The differences identified were important, and were concerned with management during the menstrual cycle and with symptoms associated with sexual activity. Menstruation-linked asthma has been shown to be a significant predictor of urgent health-care use.31 Lack of change on other sex role-related and gender role-related items, however, does not mean that the focus on women’s issues was not a salient feature of success in reaching the outcomes observed. Although the intervention included specific sex and gender content, it also attempted in a broader sense to accommodate the particular experience, and voiced concerns arising from a woman’s efforts to manage her asthma given her initial level of self-regulation. This overall female-sensitive approach combined with a focus on capacity and confidence building likely explains the findings of the study. The women in this randomized clinical trial were drawn from a large Midwestern, university-based clinical system. As a group they reflected a wide range of incomes, ages, education, and racial/ethnic 96

backgrounds. They were not selected to represent a particular population. As a result, the study findings cannot be definitively generalized to all women or to a homogenous group of women. However, given the diversity of the sample, it is likely that the intervention would be successful with a general population of women seeking service in similar venues. The intervention itself can be easily replicated and introduced into a range of clinical settings. Study Limitations Though randomization processes were based on random length-permuted blocks, it happened that more women with persistent asthma were assigned to the treatment group. As noted, this fact could have made intervention results more difficult to achieve given that the women were sicker. Conversely, it could have provided more room for women to improve. This investigation did not use clinical measures such as FEV1 as the study was primarily concerned with symptoms and functioning. Spirometric measures may be useful in assessing the impact of such an intervention. Because of resource limitations, medical record data were only collected for a sample of women to assess the reliability of the self-reported recall data and health-care use records. Further, data regarding smoking status were not collected, and this variable could influence symptoms in smokers, though observation by clinical personnel suggests that smoking rates were low in this population. Conclusion Women in the treatment group receiving education focused on the particular management problems of a woman with asthma exhibited significant improvements in their symptoms, health-care use, quality of life, days of missed work or school, levels of self-regulation, and their self-confidence to manage asthma compared to women receiving conventional asthma education 1 year subsequent to the completion of the program. There are implications for clinical practice in these findings. The consideration of a woman’s particular perspective and the experience of managing asthma and the sex-related and gender-related challenges that she faces appear to enrich a management intervention. Attention to these areas when counseling patients and their inclusion in programs offered in the clinical setting could enhance asthma outcomes for female patients. This study observed patients for 1 year. Future work should examine the long-term benefits or any decay in benefits that may occur for women with asthma over time. Original Research

ACKNOWLEDGMENT: The authors would especially like to thank Jimmy Yu, Martha DeRoeck, Jane Burton, and Susan Dara for their contributions.

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References

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1 Centers for Disease Control and Prevention. Asthma prevalence and control characteristics by race/ethnicity: United States, 2002; Division of Environmental Hazards and Health Effects, National Center for Environmental Health, Centers for Disease Control and Prevention, Department of Health and Human Services. MMRW Morb Mortal Wkly Rep 2004; 53:145–148 2 Trawick DR, Holm C, Wirth J. Influence of gender on rates of hospitalization, hospital course, and hypercapnea in highrisk patients admitted for asthma: a 10-year retrospective study at Yale-New Haven Hospital. Chest 2001; 119:115–119 3 Centers for Disease Control and Prevention. Surveillance for asthma: United States, 1980 –1999. MMRW Morb Mortal Wkly Rep 2002; 51:1–13 4 Agarwal AK, Shah A. Menstrual-linked asthma. J Asthma 1997; 34:539 –545 5 Eliasson O, Scherzer HH, DeGraff AC Jr. Morbidity in asthma in relation to the menstrual cycle. J Allergy Clin Immunol 1996; 77:87–94 6 Gibbs CJ, Coutts II, Lock R, et al. Premenstrual exacerbation of asthma. Thorax 1984; 39:833– 836 7 Hanley SP. Asthma variation with menstruation. Br J Dis Chest 1981; 75:306 –308 8 Matsuo N, Shimoda T, Matsuse H, et al. A case of menstruation-associated asthma: treatment with oral contraceptives. Chest 1999; 116:252–253 9 Barr RG, Camargo CA Jr. Hormone replacement therapy and obstructive airway diseases. Treat Respir Med 2004; 3:1–7 10 Lange P, Parner J, Prescott E, et al. Exogenous female sex steroid hormones and risk of asthma and asthma-like symptoms: a cross sectional study of the general population. Thorax 2001; 56:613– 616 11 Lieberman D, Kopernik G, Porath A, et al. Sub-clinical worsening of bronchial asthma during estrogen replacement therapy in asthmatic post-menopausal women. Maturitas 1995; 21:153–157 12 Troisi RJ, Speizer FE, Willett WC, et al. Menopause, postmenopausal estrogen preparations, and the risk of adult-onset asthma: a prospective cohort study. Am J Respir Crit Care Med 1995; 152:1183–1188 13 Blaiss MS. Management of asthma during pregnancy. Allergy Asthma Proc 2004; 25:375–379 14 Ernst P, Ghezzo H, Becklake MR. Risk factors for bronchial hyperresponsiveness in late childhood and early adolescence. Eur Respir J 2002; 20:635– 639 15 O’Hollaren MT, Yunginger JW, Offord KP, et al. Exposure to an aeroallergen as a possible precipitating factor in respiratory

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18

19 20

21

22 23 24 25 26

27 28 29 30 31

arrest in young patients with asthma. N Engl J Med 1991; 324:359 –363 Platts-Mills TA, Thomas WR, Aalberse RC, et al. Dust mite allergens and asthma: report of a second international workshop. J Allergy Clin Immunol 1992; 89:1046 –1060 Chan-Yeung M, Malo J. Table of the major inducers of occupational asthma. In: Bernstein IL, Chan-Yeung M, Malo J, eds. Asthma in the workplace. New York, NY: Marcel Dekker, 1993; 595– 623 National Asthma Education and Prevention Program. Expert panel report II: guidelines for the diagnosis and management of asthma. Bethesda, MD: National Institutes of Health, National Heart Lung and Blood Institute, 1997; Publication No. 97– 4051 Bandura A. Social foundations of thought and action: a social cognitive theory. Englewood Cliffs, NJ: Prentice Hall, 1996 Clark NM, Janz NK, Dodge JA, et al. Changes in functional health status of older women with heart disease: evaluation of a program based on self-regulation. J Gerontol B Psychol Sci Soc Sci 2000; 55:S117–S126 Bonner S, Zimmerman BJ, Martinez-Pons M, et al. The development of a structured interview to assess phases of asthma self-regulation. Presented at: the American Thoracic Society International Conference, May 20 –24, 1994; Seattle, WA Zimmerman BJ, Bonner S, Evans D, et al. Self-regulating childhood asthma: a developmental model of family change. Health Educ Behav 1995; 26:55–71 Clark NM, Gong M, Schork MA, et al. Impact of education for physicians on patient outcomes. Pediatrics 1998; 101:831– 836 Clark NM, Gong M, Schork MA, et al. Long term effects of asthma education for physicians on patient satisfaction and use of health services. Eur Respir J 2000; 16:15–21 Martin LM, Leff M, Calonge N, et al. Validation of selfreported chronic conditions and health services in a managed care population. Am J Prev Med 2000; 18:215–218 Juniper EF, Guyatt GH, Epstein RS, et al. Evaluation of impairment of health related quality of life in asthma: development of a questionnaire for use in clinical trials. Thorax 1992; 47:76 – 83 Juniper EF, Guyatt GH, Ferrie PJ, et al. Measuring quality of life in asthma. Am Rev Respir Dis 1993; 147:832– 838 Clark NM, Gong M, Kaciroti N. A model of self-regulation for control of chronic disease. Health Educ Behav 2001; 28:769 –782 Little RJA, Rubin DB. Statistical analysis with missing data. 2nd ed. New York, NY: John Wiley & Sons, 2002 McCullagh P, Nelder JA. Generalized linear models. 2nd ed. Boca Raton, FL: Chapman & Hall/CRC, 1998 Zimmerman JC, Woodruff PG, Clark S, et al. Relation between phase of menstrual cycle and emergency department visits for acute asthma. Am J Respir Crit Care Med 2000; 162:512–515

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