Nocturnal asthma

Nocturnal exacerbation of bronchoconstriction are very common among asthmatics. The underlying mechanism is complex and variable in different cases. The basis is represented by bronchial hyperreactivity which worsens at night because of intervention of different factors, among which a poor balance in autonomic and humoral control of bronchial muscle tone plays a major role. The airways are made more prone to factors eliciting bronchial obstruction (allergen, gastroesophageal reflux etc.) by the effect of other modulating factors (posture, sleep etc.). Diagnosis of nocturnal asthma may be reliably made by measuring regularly the peak expiratory flow: a morning fall higher than 20% with respect to the previous evening points out the residual bronchoconstriction. The treatment of nocturnal asthma is mandatory because of unfavourable prognostic implications: anti-inflammatory drugs are the mainstay, while long-lasting beta-stimulant may be used concomitantly for symptomatic relief