Chest
Volume 108, Issue 2, August 1995, Pages 394-400
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Clinical Investigations; Articles; Nebs and Flows
Predictors of Patient Adherence to Long-term Home Nebulizer Therapy for COPD

https://doi.org/10.1378/chest.108.2.394Get rights and content

Study objective

Patients with moderate to severe COPD are frequently prescribed expensive and complicated therapies that require adjustments in usual activities of daily living. However, little is known about factors that are associated with adherence to such treatment. The objective of this study was to identify characteristics of patients who were adherent to long-term home nebulizer therapy.

Design

Patients were stratified into two adherence groups based on average minutes of nebulizer use each day. A logistic regression model was developed to predict adherence based on baseline variables. A questionnaire was administered to patients to assess reasons for adherence to therapy.

Setting

Five clinical centers in the United States and Canada.

Participants

Nine hundred eighty-five patients with moderate to severe COPD enrolled in the Intermittent Positive Pressure Breathing (IPPB) Trial.

Interventions

Long-term home IPPB and nebulizer therapy.

Measurements and results

Altogether 50.6% of patients were adherent, and 49.4% were nonadherent. Among baseline variables, good adherence was predicted by white race, married status, abstinence from cigarettes and alcohol, serum theophylline level ≥9 μg/mL, more severe dyspnea, and reduced FEV1 (p<0.05). Subjects who were adherent to nebulizer therapy were older, better educated, had a stable lifestyle, were more likely to report that the therapy made them feel better, and were more likely to keep clinic appointments.

Conclusions

Sociodemographic, physiologic, and quality of life variables were associated with adherence to long-term nebulizer therapy.

(CHEST 1995; 108:394-400)

Section snippets

IPPB Study

Altogether 985 subjects with COPD were enrolled in five centers in the United States and Canada. The IPPB Study protocol is available elsewhere5 and is summarized for this analysis. The study was approved by the institutional committee on human research at each of the clinical centers. All subjects provided informed consent to participate in the study. Patient selection criteria are summarized in Table 1. All study participants were randomly assigned to IPPB or nebulizer therapy. They were

Results

Altogether 50.6% (n=498) of the patients were adherent (used their nebulizers 25 min/d or more), while 49.4% (n=487) were nonadherent. The mean (±SD) elapsed-time meter readings were 26.8±18.0 for all patients, 40.6±13.0 for adherent patients, and 12.5±7.5 for nonadherent patients (p<0.001). Nebulizer use did not change significantly in either of the adherence groups during the course of the study. Adherent patients reported that they used their nebulizers an average of 44.1 ±12.1 min/day,

Predictors of Adherence

We were able to predict which subjects would be adherent to long-term home nebulizer therapy by analyzing the sociodemographic, physiologic, and quality of life characteristics of subjects when they entered the study. Nebulizer-adherent subjects also tended to take oral theophylline as prescribed and keep clinic appointments.

In contrast to most studies cited in the literature,16 age, marital status, education, severity of symptoms, and race were predictors of adherence to nebulizer therapy.

ACKNOWLEDGMENTS

Participants in the Intermittent Positive Pressure Breathing Trial (an asterisk indicates a principal investigator) were the following: Clinical Centers: Baylor College of Medicine, Houston: Paul Stevens, MD;* and Ruth Abeles, RN; Loma Linda (Calif) University: John E. Hodgkin, MD;* and Eileen Zorn, RN, MS; University of Oklahoma Health Sciences Center, Oklahoma City: David C. Levin, MD:* and Brenda Jaye, RN, and Patricia K. Brannin, RN, MSN, RRT; University of California, San Francisco: Philip

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