Impact of patient-related factors on asthma control.
BACKGROUND
Patient-related factors are a significant component in the serious public health problem of poor asthma control, yet they have not been extensively studied.


OBJECTIVE
To gauge the impact of baseline patient characteristics, compliance and inhaler device manipulation on Asthma Control Score (ACS).


METHODS
ACS (between 0 and 9) was calculated from data recorded in a routine consultation in 4,362 patients with persistent asthma using a maintenance treatment with only inhaled corticosteroid and correlated with patient characteristics, compliance (using 2 methods) and critical errors in inhaler handling.


RESULTS
Mean ASC was 2.95 (95%CI: 2.88-3.02) and asthma control was unsatisfactory (i.e., ACS > or = 4) in 41.1% of subjects, with higher proportions in smokers, non-compliant patients, and those misusing their device. Mean ACS tended to rise with age, and was higher in smokers than in non-smokers (+0.83 point) and ex-smokers (+0.49 point). More than 20% of all subjects were using their inhaler device incorrectly (Turbuhaler 37.1%; Metered-dose inhaler 28.1%; Diskus 21.3%; Aerolizer 7.4%) and this was associated with a 0.84-point increase in ACS. Mean ACS was lower in the most compliant patients (-0.74 points in the 13.4% with a perfect score on a compliance questionnaire) and much lower than in the least compliant (-1.84 points in the 6.6% who reported missing 4 or more doses per week).


CONCLUSIONS
Patient-related factors including smoking, poor compliance and critical errors in device manipulation, have significant negative impact on asthma control. This could be addressed by patient education.
Molimard
Mathieu
M
Département de Pharmacologie, INSERM, Unité 657, IFR 99, Université Victor Segalen, Bordeaux cedex, France. mathieu.molimard@pharmaco.u-bordeaux2.fr
Le Gros
Vincent
V
D000280:Administration, Inhalation; D000328:Adult; D001249:Asthma / Q000188:drug therapy*; D003430:Cross-Sectional Studies; D005260:Female; D005602:France; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009330:Nebulizers and Vaporizers; D010349:Patient Compliance; D010353:Patient Education as Topic; D012307:Risk Factors; D012907:Smoking; D016312:Treatment Refusal
D005938:Glucocorticoids