Despite the fact that the onset of asthma can occur at any age, there have been few studies specifically assessing whether the therapeutic effects of asthma medications vary according to age of onset.1, 2 The present study was constructed to compare the responses to a combination of fluticasone (FP) and salmeterol (SAL) in terms of symptoms, airflow obstruction, and airway inflammation between individuals with asthma with early (<40) and late (≥65) onset. Various factors, including current medications, smoking history, asthma duration, comorbid conditions, adherence, and inhalation technique, may modify response to asthma treatment.1, 2 This prospective parallel-group study was designed to control for these modifiers. Never-smoking untreated individuals from both age groups whose asthma duration was <3 years were included. Individuals were excluded if they had other pulmonary or cardiac diseases or had been treated with any form of corticosteroid in the 8 weeks before the study. Hydrofluoroalkane (HFA)-FP/SAL (250/50 μg) was administered twice daily, and instructions were repeated monthly to all participants. Asthma control questionnaire (ACQ), spirometry, and fraction of exhaled nitric oxide (FENO) were assessed before and 3 months after HFA-FP/SAL therapy. FENO was measured using an online electrochemical nitric oxide analyzer (NIOX MINO; Aerocrine AB, Solna, Sweden) according to standard procedures.3, 4 Statistical analysis was performed using Mann–Whitney U-tests. The local ethics committee approved this trial, which was registered with the university hospital Medical Information Network (UMIN000006291). Informed written consent was obtained from each participant. Participants consisted of 16 younger individuals (seven male, nine female, 14 with atopy) with an average onset age of 27.4, and 16 elderly individuals (eight male, eight female, eight with atopy) with an average onset age of 72.3. At baseline, individuals with late onset had lower forced expiratory volume in 1-s percentage of predicted (%FEV1; 89.3 ± 7.3%) than those with early onset (80.9 ± 12.8%, P = .03), but no differences in ACQ score (1.3 ± 0.5 vs 1.4 ± 0.6, P = .7) of FENO (50 ± 18 vs 57 ± 38 ppb, P = .48) were seen between the two age groups. As shown in Figure 1, HFA-FP/SAL therapy significantly improved ACQ,%FEV1, and FENO equally in participants with early and late onset, and there was no significant difference in these outcomes between the groups 3 months after treatment (0.2 ± 0.3 vs 0.3 ± 0.3, P = .45; 94.7 ± 8.4% vs 90.1 ± 12.5%, P = .14; and 26 ± 11 vs. 24 ± 18 ppb, P = .99, respectively). Two points from the preliminary data should be emphasized. First, untreated individuals with late-onset asthma have the same degree of airway inflammation detected using FENO as those with early onset. Second, individuals with early- and late-onset asthma respond equally well to HFA-FP/SAL therapy in terms of asthma symptoms, airflow obstruction, and airway inflammation. Because inhaled corticosteroids are capable of reducing airway inflammation, thereby reducing symptoms and improving lung function, the present study indicates that airway inflammation is an important therapeutic target in persistent asthma regardless of the age of onset. It has been shown that peripheral blood eosinophil adhesion and chemotactic activities were comparable in individuals with early and late-onset asthma, and the percentages of sputum eosinophils were similar in the two age groups.5 There is also evidence that regular use of inhaled corticosteroids improves asthma-related outcomes in elderly adults.6-9 The findings of the current study suggest that regular antiinflammatory treatment and instructions are an important therapeutic strategy in asthma for all ages, and the implementation of this strategy can be expected to improve health outcomes in elderly adults. The authors thank Mr. Brent Bell for reading the manuscript. This study was supported by Grant 22591097 from the Japan Society for the Promotion of Science. No potential conflicts of interest exist with any companies whose products or services may be discussed in this article. Conflict of Interest: The editor in chief has reviewed the conflict of interest checklist provided by the authors and has determined that the authors have no financial or any other kind of personal conflicts with this paper. Author Contributions: Kazuto Matsunaga: study design and preparation of manuscript. Masakazu Ichinose: interpretation of data. Keiichiro Akamatsu and Tsunahiko Hirano: acquisition of subjects and data. Sponsor's Role: None.