Fatal asthma; is it still an epidemic?

Abstract

Background: Asthma mortality has declined since the 1980s. Nevertheless the World Health Organization (WHO) identified asthma as responsible for 225.000 deaths worldwide in 2005, and 430.000 fatal cases are expected by 2030. Some unexpected and concentrated fatal asthma events all occurred between 2013 and 2015 in Veneto, a North Eastern region of Italy, which prompted a more in-depth investigation of characteristics and risk factors.

Methods: A web search including key words related to fatal asthma in Italy between 2013 and 2015 has been performed. Concerning the cases that occurred in Veneto, subjects' clinical records have been evaluated and details about concomitant weather conditions, pollutants and pollen count have been collected.

Results: Twenty-three cases of asthma deaths were found in Italy; 16 of them (69%) occurred in the Veneto Region. A prevalence of male and young age was observed. Most of patients were atopic, died in the night-time hours and during the weekends. The possible risk factors identified were the sensitization to alternaria, previous near fatal asthma attacks and the incorrect treatment of the disease. Weather condition did not appear to be related to the fatal exacerbations, whereas among the pollutants only ozone was detected over the accepted limits. Smoking habits, possible drug abuse and concomitant complementary therapies might be regarded as further risk factors.

Discussion: Although not free from potential biases, our web search and further investigations highlight an increasing asthma mortality trend, similarly to what other observatories report. The analysis of available clinical data suggests that the lack of treatment more than a severe asthma phenotype characterizes the fatal events.

Conclusions: Asthma mortality still represents a critical issue in the management of the disease, particularly in youngsters. Once more the inadequate treatment and the lack of adherence seem to be not only related to the uncontrolled asthma but also to asthma mortality.

Keywords: Alternaria; Asthma exacerbations; Asthma mortality; Fatal asthma.

Fig. 1

Trend of asthma mortality according to the Italian National Institute of Statistics (ISTAT) from 2009 to 2012

Fig. 2

Levels of pollutants (NO, PM₁₀ and O₃) registered at the place and at the time of the deaths. On x-axis patients’ initials are reported. In 3 days the concentration of ozone was above the accepted limits (120 μcg/m³), whereas only in 1 day the level of PM₁₀ was significantly over the permitted values (50 μcg/m³)

Fig. 3

Aerobiological data at the time and places of the deaths are shown. On x-axis patients’ initials are reported. The pollen count was low for all pollens detected (grass, birch, parietaria and ragweed) whereas in 6 days a high concentration of alternaria was registered

Fig. 4

A massive infiltration and airways obstruction has been detected in the airways of a patient who died during the summer (a). The image shows a section of bronchus - hematoxylin-eosin stain - magnification × 100. Red arrow: bronchial lumen occluded by amorphous eosinophilic material corresponding to mucus plugs, mixed with inflammatory cells and epithelial cells. Green arrow: peribronchial and sub-mucosal hyperaemia, thickening of the basal membrane with muscle hypertrophy. Blue arrow: neutrophilic and limphomonocitary inflammation. The patient was sensitized to alternaria, which was detected in the airways (b); the outdoor concentration of the fungal mold was high at the time of the death