Epidemiological data on chronic bronchitis in France

Definitions Cough and expectorations present for at least 3 months every ye ar for at least 2 consecutive years are the characteristic feature of chron ic bronchitis. Pulmonary emphysema is a permanent distension of the air spa ces beyond the bronchioles with destruction of the alveolar walls. Chronic obstructive pulmonary disease (COPD), which often develops after chronic br onchitis, is defined as an obstructive ventilatory syndrome demonstrated by a forced expiratory volume in 1 second / vital capacity (FEV1/VC) ratio be low 70 %. Acute exacerbation of chronic bronchitis is characterized by wors ening cough, expectoration and/or dyspnea. Risk factors Active smoking is a predominant risk factor for COPD; the decr ease in FEV1 is tightly correlated with individual sensitivity to tobacco s moke. Other risk factors have been identified: occupational exposure to air borne contaminants, alpha -antitripsin deficiency. Epidemiological data A recent survey showed that the prevalence of chronic bronchitis in the adult population in France aged over 25 years is an estim ated 1.2 to 2 million people without co-morbidity and an estimated 1.6 to 2 .8 million including people with co-morbidity (for instance asthma). The an nual death toll reaches 10,000 to 12,000. Management In patients without co-morbidity, only about 30 % of all cases o f chronic bronchitis are diagnosed. Medical care is given to about 15 %. Th e impact of acute exacerbations (average 3 episodes per year according to t he survey), both in number and in terms of quality of life, would be undere stimated.