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Ineffectiveness of telephone-based environmental control intervention to improve asthma outcomes

2010; Elsevier BV; Volume: 126; Issue: 4 Linguagem: Inglês

10.1016/j.jaci.2010.07.035

1097-6825

Michael Schätz, Robert S. Zeiger,

Behavioral Health and Interventions

To the Editor: Current guidelines recommend testing for allergic sensitization (skin or blood tests) for all patients with persistent or uncontrolled asthma and environmental control education for those patients with positive test results.1Expert Panel Report 3: guidelines for the diagnosis and management of asthma—summary report 2007.J Allergy Clin Immunol. 2007; 120: S94-S138PubMed Google Scholar Practical barriers to following this recommendation include cost, additional visits, and possible need for specialist referral. The purpose of our study was to test a relatively undemanding, convenient, and inexpensive means to fulfill this recommendation in a large health plan without the need for a physician’s office visit or specialist referral. Reports of improved asthma outcomes using telephone interventions2Donald K.J. McBurney H. Teichtahl H. Irving L. A pilot study of telephone-based asthma management.Aust Fam Physician. 2008; 37: 170-173PubMed Google Scholar, 3Patel R.R. Saltoun C.A. Grammer L.C. Improving asthma care for the elderly: a randomized controlled trial using a simple telephone intervention.J Asthma. 2009; 46: 30-35Crossref PubMed Scopus (14) Google Scholar supported a telephone-based intervention for this study. Asthmatic patients aged 18 to 56 years who had not seen an allergist in the prior year were identified from Southern California Kaiser Permanente (SCKP) administrative data. Automated telephone calls using speech-recognition technology4Schatz M. Zeiger R.S. Drane A. Harden K. Cibildak A. Oosterman J.E. et al.Reliability and predictive validity of the Asthma Control Test administered by telephone calls using speech recognition technology.J Allergy Clin Immunol. 2007; 119: 336-343Abstract Full Text Full Text PDF PubMed Scopus (76) Google Scholar were made to randomly selected eligible patients until study recruitment was complete (see below). On the call, the Asthma Control Test (ACT) was administered, as previously reported,4Schatz M. Zeiger R.S. Drane A. Harden K. Cibildak A. Oosterman J.E. et al.Reliability and predictive validity of the Asthma Control Test administered by telephone calls using speech recognition technology.J Allergy Clin Immunol. 2007; 119: 336-343Abstract Full Text Full Text PDF PubMed Scopus (76) Google Scholar and patients with uncontrolled asthma (ACT score <20) were asked whether they would be interested in participating in the study. Study participation was confirmed on a follow-up “live” telephone call, at which time a baseline ACT score was obtained, and consent forms approved by the SCKP institutional review board were completed by mail. Consenting patients were randomly assigned to the intervention or control group. All study patients were advised to contact their regular physician regarding their uncontrolled asthma. The control group did not receive any further interventions. The intervention group was asked to go to any Kaiser laboratory to obtain an allergy blood test for aeroallergens (Cap RAST to a panel of selected tree, grass, and weed pollens; mold spores; dust mite; and cat and dog dander). Patients were advised of their specific sensitivities by mail, and all allergic patients were sent written (Kaiser Permanente’s “Controlling Asthma Triggers”) and video (American Academy of Allergy, Asthma & Immunology’s “Environmental Control Measures”) environmental control information regarding pollen, mite, mold, pet dander, tobacco smoke, and other irritants. Patients in the intervention group were called 1 month after they were sent environmental control information to be sure they received the information, to reinforce the advice, and to answer questions. Study patients were called 6 months after entering the study by research personnel blinded to study group to complete a follow-up ACT test and to determine whether participants had made any changes in their home environments (“Have you made any changes in your home environment in response to any of the information you have received during this study?”). Control patients might have made environmental changes randomly or in response to being told on the screening or baseline call that their asthma was not well controlled, but they did not receive any specific environmental control information during the study. Administrative data information (asthma hospitalizations, emergency department visits, oral corticosteroid dispensings, and number of short-acting β-agonist canister dispensings) were obtained for the 6 months before and 6 months after entry into the study for study patients (intervention and control), as well as 6 months before and after telephone ACT completion by patients who did not enter the study. Power analysis for this study was based on unpublished data from our San Diego Kaiser Permanente patients who completed the ACT administered on 2 occasions 3 months apart by automated telephone calls using speech-recognition technology. Patients with uncontrolled asthma (ACT score <20) on the first call were advised to contact their primary care physician. Of 167 patients with uncontrolled asthma on the first call, 60% continued to have uncontrolled symptoms on the second call. We thus assumed that 60% of our control patients would continue to have uncontrolled asthma with the same intervention (advice to contact their primary care physician). The study was powered to provide 80% power (2-tailed P = .05) to detect a clinically meaningful 33% decrease in follow-up uncontrolled asthma by ACT score (the primary outcome variable) from 60% in the control group to 40% in the intervention group, which was 100 patients per group. We planned to enroll 150 patients per group to account for the expected dropout rate of about 30% we have experienced in prior telephone surveys. The study was approved by the SCKP Institutional Review Board. While identifying the 300 study participants with uncontrolled asthma (ACT score <20), automated telephone calls during recruitment identified 623 patients with uncontrolled asthma who chose not to participate and 1909 patients with controlled asthma (ACT score ≥20) who were ineligible. The 300 study participants were randomized to the intervention group (n = 149) and to the control group (n = 151); the groups did not differ significantly by age or sex (data not shown). Allergy blood tests were completed by 117 (78.5%) of 149 intervention patients, of whom 72 (61.5%) had positive test results. More patients in the intervention group than the control group continued to have uncontrolled asthma on their baseline telephone call (P < .05, Table I).5Schatz M. Kosinski M. Yarlas A.S. Hanlon J. Watson M.E. Jhingran P. The minimally important difference of the Asthma Control Test.J Allergy Clin Immunol. 2009; 124: 719-723Abstract Full Text Full Text PDF PubMed Scopus (395) Google Scholar, 6Schatz M. Zeiger R.S. Vollmer W.M. Mosen D. Apter A.J. Stibolt T.B. et al.Validation of a beta-agonist long-term asthma control scale derived from computerized pharmacy data.J Allergy Clin Immunol. 2006; 117: 995-1000Abstract Full Text Full Text PDF PubMed Scopus (99) Google Scholar It is not clear why 27% of intervention patients and 39% of control patients had improved to controlled status on their baseline ACT from uncontrolled status on their screening ACT, although being told on the screening call of their uncontrolled status might have played a role by encouraging improved medication adherence or medical attention. No other significant differences between groups in ACT scores were seen at baseline or at 6 months or in changes between baseline and 6 months (Table I). Restriction of the analyses to intervention patients who completed the blood test or to allergic patients did not change the results (data not shown). There were also no significant differences between the intervention and control groups in the proportions of patients who reported making home environmental changes during the study (23.8% vs 25.2%. respectively). Intervention patients who reported making environmental changes had better outcomes than those who did not report making such changes (Table I), but the differences did not reach statistical significance.Table IACT results in study patientsBaseline6 mo6-mo InterventionACT parameterIntervention (n = 149)Control (n = 151)Intervention (n = 126)Control (n =111)Made changes (n = 30)Did not make changes (n = 96)Mean (SD)16.5 (4.5)17.3 (4.7)18.1 (4.4)18.2 (4.4)19.5 (3.5)17.7 (4.5)Percentage uncontrolled (ACT score <20)73.1∗P = .02 versus control patients at baseline. No other significant differences between groups were seen at either time period.60.952.456.840.056.3Mean (SD) change from baseline——1.6 (4.4)0.7 (4.4)2.5 (4.3)1.3 (4.4)Percentage increase from baseline by ≥3 (ACT minimal important difference5Schatz M. Kosinski M. Yarlas A.S. Hanlon J. Watson M.E. Jhingran P. The minimally important difference of the Asthma Control Test.J Allergy Clin Immunol. 2009; 124: 719-723Abstract Full Text Full Text PDF PubMed Scopus (395) Google Scholar)——40.533.350.037.5∗ P = .02 versus control patients at baseline. No other significant differences between groups were seen at either time period. Open table in a new tab There were no significant differences between the intervention and control study groups regarding asthma hospitalizations or emergency department visits, any oral corticosteroid dispensings, or high short-acting β-agonist canister dipensings in the 6 months before or after entering the study (Table II, Table III). Patients with controlled asthma not in the study did have less evidence of prior and subsequent medical use compared with patients with uncontrolled asthma not in the study (P < .01, Table II, Table III).Table IIAdministrative data markers of uncontrolled asthma in patients in the study 6 months before and 6 months after study initiation∗There were no significant differences in results between intervention patients versus control patients.GroupParameterInterventionControlAsthma hospitalization or ED visit†Only patients with continuous enrollment during the 6 months before and 6 months after study initiation were included in these analyses.(n = 139)(n = 139) Before2.9%2.9% After4.3%2.9%Any oral corticosteroid dispensing†Only patients with continuous enrollment during the 6 months before and 6 months after study initiation were included in these analyses.‡Only patients with pharmacy benefits during the 6 months before and 6 months after study initiation were included in these analyses.(n = 131)(n = 134) Before22.9%20.1% After17.6%20.9%SABA ≥7†Only patients with continuous enrollment during the 6 months before and 6 months after study initiation were included in these analyses.‡Only patients with pharmacy benefits during the 6 months before and 6 months after study initiation were included in these analyses.§This SABA cutoff was based on a previously validated β-agonist long-term control scale.6(n = 131)(n = 134) Before6.1%9.0% After9.2%6.0%ED, Emergency department; SABA, short-acting β-agonist canisters.∗ There were no significant differences in results between intervention patients versus control patients.† Only patients with continuous enrollment during the 6 months before and 6 months after study initiation were included in these analyses.‡ Only patients with pharmacy benefits during the 6 months before and 6 months after study initiation were included in these analyses.§ This SABA cutoff was based on a previously validated β-agonist long-term control scale.6Schatz M. Zeiger R.S. Vollmer W.M. Mosen D. Apter A.J. Stibolt T.B. et al.Validation of a beta-agonist long-term asthma control scale derived from computerized pharmacy data.J Allergy Clin Immunol. 2006; 117: 995-1000Abstract Full Text Full Text PDF PubMed Scopus (99) Google Scholar Open table in a new tab Table IIIAdministrative data markers of uncontrolled asthma in patients not in the study during 6 months before and 6 months after recruitmentGroupParameterUncontrolledControlledAsthma hospitalization or ED visit∗Only patients with continuous enrollment during the 6 months before and 6 months after study recruitment were included in these analyses.(n = 547)(n = 1750) Before2.9%0.9%†P < .01 in patients with controlled asthma not in the study versus those with uncontrolled asthma not in the study. After1.6%1.7%Any oral corticosteroid dispensing∗Only patients with continuous enrollment during the 6 months before and 6 months after study recruitment were included in these analyses.‡Only patients with pharmacy benefits during the 6 months before and 6 months after study recruitment were included in these analyses.(n = 523)(n = 1683) Before17.8%10.5%†P < .01 in patients with controlled asthma not in the study versus those with uncontrolled asthma not in the study. After17.2%11.7%†P < .01 in patients with controlled asthma not in the study versus those with uncontrolled asthma not in the study.SABA ≥7∗Only patients with continuous enrollment during the 6 months before and 6 months after study recruitment were included in these analyses.‡Only patients with pharmacy benefits during the 6 months before and 6 months after study recruitment were included in these analyses.§This SABA cutoff was based on a previously validated β-agonist long-term control scale.6(n = 523)(n = 1683) Before6.7%2.0%†P < .01 in patients with controlled asthma not in the study versus those with uncontrolled asthma not in the study. After6.3%3.5%†P < .01 in patients with controlled asthma not in the study versus those with uncontrolled asthma not in the study.ED, Emergency department; SABA, short-acting β-agonist canisters.∗ Only patients with continuous enrollment during the 6 months before and 6 months after study recruitment were included in these analyses.† P < .01 in patients with controlled asthma not in the study versus those with uncontrolled asthma not in the study.‡ Only patients with pharmacy benefits during the 6 months before and 6 months after study recruitment were included in these analyses.§ This SABA cutoff was based on a previously validated β-agonist long-term control scale.6Schatz M. Zeiger R.S. Vollmer W.M. Mosen D. Apter A.J. Stibolt T.B. et al.Validation of a beta-agonist long-term asthma control scale derived from computerized pharmacy data.J Allergy Clin Immunol. 2006; 117: 995-1000Abstract Full Text Full Text PDF PubMed Scopus (99) Google Scholar Open table in a new tab ED, Emergency department; SABA, short-acting β-agonist canisters. ED, Emergency department; SABA, short-acting β-agonist canisters. The purpose of this study was to test an environmental control intervention for asthma that did not require a physician’s office visit. We are reporting the negative results because we believe it is important to report what does not work to facilitate the design of interventions that will work. Actually, certain aspects of this strategy did work. We were able to identify by means of automated telephone technology patients with uncontrolled asthma who would subsequently manifest significantly more impairment and risk indicators of uncontrolled asthma over the following 6 months compared with patients with controlled asthma. A majority of intervention patients did complete their blood tests, and the majority of these patients had evidence of allergic sensitization. In addition, there was evidence of improvement in asthma control in both the intervention and control groups (Table I). However, the intervention was not strong enough to induce intervention patients to make more home environmental changes than control patients, and therefore it is not surprising that asthma outcomes did not improve significantly more in intervention patients than in control patients. It is potentially encouraging that intervention patients who reported making changes appeared to do better than those who did not report making changes, but these differences were not statistically significant in this subgroup analysis, and even if significant, such improvement could not be definitively attributed to the intervention (versus, for example, other characteristics of patients who make changes). It is not certain what more would need to be done for a successful intervention, but possibilities include the following: (1) taking into account a history-RAST correlation to determine individual patient relevance of the allergic sensitization; (2) a more tailored environmental control education program based on a patient’s specific sensitization and environment; (3) a more individualized environmental control education program, taking into account the patient’s total asthma state (severity, control, and treatment); (4) 1 or more in-person sessions to optimize information transfer and bidirectional communication; and (5) home visits. Further studies will be necessary to determine which of these or other aspects of an environmental control intervention (eg, targeting patients who express a willingness to make changes) would successfully improve asthma outcomes in allergic patients. However, considering the role allergens can play in asthma and the ameliorative effect of environmental control,1Expert Panel Report 3: guidelines for the diagnosis and management of asthma—summary report 2007.J Allergy Clin Immunol. 2007; 120: S94-S138PubMed Google Scholar the economic and human costs of uncontrolled asthma, and the expense and possible side effects of medications, such interventions would certainly be worth pursuing.