[Oral health-related quality of life in rare diseases associated with oral symptoms, diagnostic delay, and sex]

Background: In Germany, around four million people are affected by a rare disease, from which 15% show orofacial manifestations.

Aim of the study: The aim of this cross-sectional study was to determine the oral health-related quality of life of people with rare diseases and to investigate the relationship between oral symptoms, diagnostic delay, and gender.

Materials and methods: A questionnaire with open-ended questions, including questions from the validated oral health impact profile (OHIP) G14 questionnaire, was developed to survey the subjective oral health-related quality of life. The questionnaire was sent to 125 German member associations of the umbrella organization of self-help groups. The correlation between OHIP values and the three factors was evaluated using a regression model with a significance level of p = 0.01.

Results: In total, 473 participants affected by 96 different rare diseases were included in this analysis. The OHIP value for participants without oral manifestations was 6.54 points lower than for those with oral symptoms (p = 0.001). For oral symptoms, the OHIP increased by 0.080 points (p = 0.014) with each year of diagnostic delay. A connection with sex was not found.

Conclusion: Regardless of the presence of oral symptoms, people with rare diseases in Germany show a poorer oral health-related quality of life than is known to the normal population. If oral symptoms are present, they show a negative correlation with oral health-related quality of life. On average, it takes 8.37 years for a disease to be correctly diagnosed. The earlier a rare disease is diagnosed, the better the oral health-related quality of life of those affected.