Stepping Down of Asthma Medication in Controlled Asthma

Background:

The most common asthma drugs, namely inhaled glucocorticoids (ICS) and long-acting beta-2 sympathomimetic drugs (LABA) carry a risk of adverse effects, some of which being potentially severe. Therefore, current guidelines for asthma management recommend that, after a period of symptom control, a reduction of the dose and cessation of the ICSs and LABAs should be attempted. However, reduction in asthma medications sometimes leads to an exacerbation of asthma. Therefore both physicians and asthmatics are often reluctant to reduce or stop asthma medications and asthma over-medication often occurs. A test that could identify those asthmatics who probably would tolerate asthma medication reduction would be useful.

Objectives:

1. To investigate whether airway responsiveness to hypertonic saline can predict the outcome of asthma treatment reduction in subjects with controlled asthma.
2. To get an estimate about how large a proportion of Finnish asthmatic patients use their medications with unnecessarily high doses or would even manage well without any asthma medications.

Study hypothesis:

1. Airway responsiveness to hypertonic saline can predict the outcome of asthma treatment reduction
2. Most of the Finnish asthmatic patients use their medications with unnecessarily high doses

Methods:

This is a prospective study in which the physician responsible for the subject management and medications is blinded from the saline challenge results and the nurse performing the saline challenges is blinded from medications 70 asthmatic patients with both inhaled ICS and LABA will be recruited. Asthma must be well controlled (Juniper's Asthma Control Questionnaire score equal or less than 0.75 ).

The asthma medications will be reduced in three steps, in six weeks' intervals, up to total cessation of asthma drugs or up to asthma exacerbation. The criteria for asthma exacerbation are strictly defined. First step: LABA will be discontinued. The ICS is continued. Second step: medium to high daily ICS dose is reduced to low daily dose. Third step: The low ICS dose will be stopped. Before each reduction, saline challenge will be performed. Asthma diary is kept throughout the study and the subjects will be provided a direct telephone number to a respiratory physician during all hours of day.