Pulmonary fibrosis is a condition that causes lung scarring and stiffness. It develops when the alveoli, tiny air sacs that transfer oxygen to the blood, become damaged and inflamed. Body tries to heal the damage with scars, but these scars collapse the alveoli and make the lungs less elastic. Changes in the lungs can also increase the blood pressure in the pulmonary artery.
In Finland, the analysis on pulmonary fibrosis got the result as three different methodologies of epidemiological studies were most commonly used, namely: (1) national registry databases, (2) questionnaire-based studies, and (3) analysis of the health care system's own registry databases. The overall prevalence and incidence of IPF varied in these studies between 0.5-27.9/100,000 and 0.22-8.8/100,000, respectively. According to four studies the mortality and incidence of IPF are rising.