Morbidity and total costs
No precise data are available for morbidity or the total costs of ILD. However, it can be assumed that the costs are high for these chronic diseases, as respiratory impairment causes many patients to give up work, some need chronic home oxygen therapy, and some undergo lung transplantation.
Hospital admissions and hospital days
Extensive European hospital admission data are available from the WHO Hospital Morbidity Database. These data show that the age-standardised hospital admission rate for ILD was highest (more than 40 per 100 000 people) in Austria, Denmark, Norway, Finland, Poland and Slovakia (figure 3).
The hospital admission rate for the different subgroups of ILD varies markedly. For sarcoidosis, the WHO Hospital Morbidity Database (2011) showed that it was generally less than 5 per 100 000 people, but was more than 10 per 100 000 people in Austria, Poland and Slovakia. The admission rate for chronic ILD (including IPF) was generally less than 10 per 100 000 people, but was higher than 20 per 100 000 people in Denmark and Slovakia. For CTD, the admission rate was generally less than 15 per 100 000 people but was about 30 per 100 000 people in Austria and Norway. For EAA, the admission/discharge rate was generally very low but was more than 4 per 100 000 people in Austria and Luxembourg (figure 4).
The average length of hospital stay was generally 8–10 days; the shortest average stay was about 6 days in Denmark and Norway, and the longest average stay was 12 days in Switzerland.
No precise data are available for drug/treatment costs of ILD. In the assessment of costs, the following aspects need to be taken into consideration: chronic use of anti-inflammatory drugs and antifibrotic agents (partly in clinical trials); frequent use of antibiotics; ambulatory oxygen therapy (especially lightweight, portable, liquid-oxygen containers) used in the advanced stages of the disease; and the possible cost of pulmonary rehabilitation and lung transplantation.
Working days lost
There are no exact data on working days lost due to ILD. However, the majority of patients with active ILD who are not yet retired are unable to work, mainly because of exertional breathlessness. In those with occupational ILD, avoidance of exposure and transfer to another job is the logical measure.