Asthma control, quality of life, and the role of patient enablement: a cross-sectional observational study.

BACKGROUND: Self-assessment of asthma and a stronger doctor-patient relationship can improve asthma outcomes. Evidence for the influence of patient enablement on quality of life and the control of asthma is lacking. AIMS: To assess asthma severity, medication use, asthma control, and patient enablement in patients with asthma treated in primary care and to study the relationship between these variables and quality of life. METHODS: A cross-sectional study was conducted in an urban clinic in northern Portugal. Data were collected from both clinical records and questionnaires from a random sample of asthma patients. The modified Patient Enablement Instrument, the Asthma Quality of Life Questionnaire, and the Asthma Control Questionnaire were used. Peak expiratory flow and forced expiratory volume in one second (FEV1) were measured. Receiver operating characteristic curve analysis was performed to establish cut-off values for the quality of life measurements. The associations between enablement, asthma control, and quality of life were tested using logistic regression models. RESULTS: The study sample included 180 patients. There was a strong correlation between asthma control and quality of life (r=0.81, p<0.001). A weak association between patient enablement and asthma control and quality of life was found in the logistic regression models. Poor control of asthma was associated with female gender, concomitant co-morbidities, reduced FEV1, and increased severity of asthma. CONCLUSIONS: The weak correlation between enablement and asthma control requires further study to determine if improved enablement can improve asthma outcomes independent of gender, severity, and concomitant co-morbidities. This study confirms the strong correlation between asthma control and quality of life.

Asthma in an urban population in Portugal: a prevalence study.

BACKGROUND: The prevalence and incidence of asthma are believed to be increasing but research on the true incidence, prevalence and mortality from asthma has met methodological obstacles since it has been difficult to define and diagnose asthma in epidemiological terms. New and widely accepted diagnostic criteria for asthma present opportunities for progress in this field. Studies conducted in Portugal have estimated the disease prevalence between 3% and 15%. Available epidemiological data present a significant variability due to methodological obstacles. AIM: To estimate the true prevalence of asthma by gender and age groups in the population of the area covered by one urban Health Centre in Portugal. METHOD: An observational study was conducted between February and July 2009 at the Horizonte Family Health Unit in Matosinhos, Portugal. A random sample of 590 patients, stratified by age and gender was obtained from the practice database of registered patients. Data was collected using a patient questionnaire based on respiratory symptoms and the physician's best knowledge of the patient's asthma status. The prevalence of asthma was calculated by age and gender. RESULTS: Data were obtained from 576 patients (97.6% response rate). The mean age for patients with asthma was 27.0 years (95% CI: 20.95 to 33.16). This was lower than the mean age for non-asthmatics but the difference was not statistically significant. Asthma was diagnosed in 59 persons giving a prevalence of 10.24% (95% CI: 8.16 to 12.32). There was no statistically significant difference in the prevalence of asthma by gender. CONCLUSION: The prevalence of asthma found in the present study was higher than that found in some studies, though lower than that found in other studies. Further studies in other regions of Portugal are required to confirm these findings.

Quality of life in asthmatic outpatients.

Asthma patients incur a great cost in terms of loss of quality of life. The purpose of this study is to evaluate the relative contribution and relationship of several patient- and disease-related factors, measured by several variables, to the quality of life in adults with asthma. Two hundred and ten asthmatic outpatients over 18 years old, registered in a Family Health Unit, were randomly selected to complete the Asthma Quality of Life (AQLQ) and Short Form Generic questionnaires (SF-36), respectively. Single and multiple linear regression models were developed to explain the variability of the summary scores of AQLQ and Physical and Mental Health SF-36. As potential predictors, the following independent variables were used: gender, age, number of comorbidities, asthma severity following the Global Initiative for Asthma (GINA) criteria, asthma control (measured by ACQ questionnaire), %FEV1 (forced expiratory volume in the first second) and, for the first time, Graffar Score to assess socioeconomical features. The Graffar Score is an index that divides the population in 5 socioeconomic layers. We report the best Adjusted R Square of these models published in the literature, ranging from 0.40 to 0.76. Women showed poorer quality of life than men. The best predictor of AQLQ was ACQ, followed by Asthma Severity, Gender and %FEV1. The best predictors of Physical and Mental Health SF-36 were, by decreasing importance, ACQ, number of comorbidities, Gender and Graffar Score. We note that the variable number of comorbidities was included in both SF-36 models, but not in AQLQ model. Asthma Severity and %FEV1 did not enter into SF-36 models. We conclude that besides clinical and functional measures, the evaluation process of the overall health status must incorporate quality-of-life measures.