Introduction:
Crohn’s disease is a chronic condition that affects the functioning and life of the patients. Quality of life of patients affected by the disease is of particular importance because it allows better functioning in all dimensions of life. It is essential to identify the numerous factors that affect the patients’ of quality of life.

Aim of the research:
To search for medical factors that influence the quality of life of patients affected by Crohn’s disease.

Material and methods:
The study was conducted using a diagnostic survey. The study group comprised 100 adult patients with Crohn’s disease hospitalised in the Gastroenterology Clinic of the Autonomous Public Hospital Complex No.1 of Pomeranian Medical University in Szczecin. The study was conducted in accordance with the Declaration of Helsinki. The standardised quality of life questionnaire SF-36v2 and an original questionnaire were used. The collected data were statistically analysed.

Results:
The analysis demonstrated a statistically significant effect of disease duration on quality of life as regards social functioning and mental health (p < 0.05). The course of the disease was found to affect all domains and dimensions of quality of life (p < 0.05). Treatment modality had a statistically significant influence only on the domain of physical functioning (p < 0.05). The number of hospitalisations in the year preceding the study was found to have a significant effect only on particular domains (p < 0.05).

Conclusions:
The course of the disease had the most significant effect on the quality of life of patients with Crohn’s disease. Other significant factors are determining the tailored method of treatment and disease duration.