Does oral health-related quality of life of patients after solid organ transplantation indicate a response shift? Results of a systematic review

BACKGROUND: The physical oral health and dental behaviour of patients after solid organ transplantation (SOT) has repeatedly been reported as insufficient. The objective of this systematic review was to detect whether the oral health-related quality of life (OHRQoL) of patients after SOT is reduced compared to that of healthy individuals. METHODS: A systematic literature search was performed by two independent individuals based on the PubMed, Web of Science and Scopus databases by using the following search terms: “transplantation” AND “oral health-related quality of life”. The findings were checked to determine eligibility, whereby publication prior to 31 October 2020, examination of adult patients (age at least 18 years) with SOT, reporting of an OHRQoL outcome and full text in English language were the prerequisites for inclusion in the qualitative analysis. Quality appraisal of the included studies was performed using the Agency for Healthcare Research and Quality methodology checklist. RESULTS: Seven of 25 studies that examined patients after kidney (3), heart (2), liver (1) and lung transplantation (1) were included. Four studies included healthy controls, and five studies included a cohort of patients before transplantation for comparison. Clinical oral health examinations were heterogeneous between groups. The majority of studies (5/7) applied the short form of the “Oral Health Impact Profile” (OHIP 14) to assess OHRQoL. The OHIP 14 values ranged between 1.7 and 8.9 across studies, indicating an unaffected or just slightly reduced OHRQoL. Only one study found better OHRQoL in patients after SOT compared to a group before SOT, and one study confirmed worse OHRQoL of SOT recipients compared to a healthy control. Only two studies revealed an association between OHRQoL and oral health parameters. Furthermore, two studies each found a relationship between OHRQoL and general health-related quality of life or disease-related parameters. CONCLUSIONS: Patients after SOT show an unaffected or only slightly reduced OHRQoL, which was mainly independent of the insufficient oral status. This might indicate a shift in the perception threshold for oral diseases and conditions caused by the general health burden related to the SOT.