Dr Surya Kant
Mid-afternoon dosing of inhaled corticosteroid (ICS), between 3-4 pm, is most effective in decreasing nocturnal worsening of asthma, compared to morning or twice-daily dose, without increasing the steroid-associated morbidity. These findings from a UK study were published in the journal Thorax.1
This randomized, three-way crossover trial was conducted to evaluate the impact of the time of dosing of ICS on lung function and biomarkers in patients with mild to moderate atopic asthma. Twenty-five participants were randomized to receive beclometasone dipropionate in one of the following three regimens for 28 days: single dose of 400 µg once daily in the morning (08:00–09:00, ODAM), 400 µg once daily dose in the afternoon (15:00–16:00, ODPM), or twice daily dose of 200 µg in the morning and evening (BD) (08:00-09:00 and 20:00 and 21:00). Each regimen had a two-week washout period between phases. Spirometry readings and biomarker (blood eosinophils, serum cortisol) levels were measured every six hours over 24 hours after the run-in and post-treatment periods.
Twenty-one out of the 26 participants completed all treatment regimens. All the three regimens improved nocturnal lung function. However, the largest improvement in evening (measured at 22:00) lung function was seen with the ODPM regimen (+160 ml) compared with ODAM (-20 ml) and BD (+80 ml). ODPM yielded superior suppression of nocturnal (22:00 and 04:00) blood eosinophil counts compared with the other two regimens. All three regimens improved overall asthma control, reduced fractional exhaled nitric oxide, and lowered serum cortisol, with no significant between-group differences.
Asthma symptoms usually worsen at night or in early morning. The present study illustrates that ODPM dosing of ICS effectively improved nocturnal lung function and reduced inflammation than the other dosage timings investigated in the study. Therefore, prescribing treatment in accordance with the body’s circadian rhythms enhances the efficacy of ICS and paves the way for personalized dosing schedules. Nonetheless, the authors note the need for further trials to confirm these findings and to determine which patients would benefit the most from chronotherapy.
Reference
1. Wang R, et al. The impact of dosage timing for inhaled corticosteroids in asthma: a randomised three-way crossover trial. Thorax. 2025 Jul 15;80(8):504-511. doi: 10.1136/thorax-2024-222073.
Dr Surya Kant is Professor and Head, Dept. of Respiratory Medicine, KGMU, Lucknow, UP. National Vice Chairman IMA-AMS