Comorbid disease in asthma: the importance of diagnosis

ABSTRACT

William Osler's comprehensive definition of bronchial asthma as "a neurotic affection characterized by hyperemia and turgescence of the mucosa of the smaller bronchial tubes … a peculiar exudate of mucin attacks … due to direct irritation of the bronchial mucosa or induced reflexly, by irritation of the nasal mucosa, and indirectly by reflex influences from stomach, intestines or genital organs" has been chiseled away to a chronic inflammatory disorder of the airways [1]. Asthma’s sharp climb in developing countries parallels their growing urbanization and westernization, eclipsing its rising prevalence in developed nations. Disease morbidity and mortality is higher in low- and lower–middle-income countries [101] particularly among the elderly, where atypical presentations and comorbidities render it likely to be underdiagnosed [2]. Common comorbidities associated with frequent exacerbations in difficult-to-treat asthma include hiatus hernia with or without associated gastroesophageal reflux disease (GERD), rhinosinusitis, recurrent respiratory infections, psychological disturbances and obstructive sleep apnea (OSA) [3,4]. Undiagnosed comorbid disease influences diagnosis, treatment response, disease management and control of asthma.