Subjective Oral Dryness following Hematopoietic Cell Transplantation: A Report from the Orastem Study

Abstract

Xerostomia, or subjective oral dryness, is a serious complaint after haematopoietic cell transplantation (HCT). Xerostomia is rated as one of the most bothersome symptoms by HCT recipients, affecting quality of life negatively. This sub-study of the Orastem study, a prospective, longitudinal, international, observational, multicentre study, aims to describe the prevalence and severity of xerostomia following HCT. Furthermore, the effect of the conditioning regimen, the type of transplantation and oral mucosal changes related to chronic graft-versus-host disease (cGvHD) in the development of xerostomia were studied. HCT recipients rated xerostomia on a 0-10 scale before the conditioning regimen, several times early post-HCT, and after 3 months, while only allogeneic HCT recipients also answered the question after 6 and 12 months. Furthermore, stimulated whole mouth saliva was collected several times. Linear regression models and longitudinal mixed effects models were created to investigate the influence of risk indicators on xerostomia. In total, 99 autologous and 163 allogeneic HCT recipients were included from 6 study sites in Sweden, Canada, the Netherlands and the USA. The prevalence of xerostomia was 40% before the conditioning regimen, 87% early post-HCT and 64% after 3 months. Complaints after autologous HCT were transient in nature, while the severity of xerostomia in allogeneic HCT recipients remained elevated 12 months post-treatment. Compared to autologous HCT recipients, allogeneic recipients experienced 1.0 point more xerostomia (95% CI: 0.1 - 2.0) early post-HCT, and 1.7 points more (95% CI: 0.4 - 3.0) after 3 months. Allogeneic HCT recipients receiving a high intensity conditioning regimen experienced more xerostomia compared to those receiving a non-myeloablative or reduced intensity conditioning regimen. The difference was 2.0 points (95% CI: 1.1 - 2.9) early post-HCT, 1.8 points (95% CI: 0.3 - 3.3) after 3 months and 1.7 points (95% CI: 0.0 - 3.3) after 12 months. Total body irradiation as part of the conditioning regimen and oral mucosal changes related to cGvHD did not significantly influence the severity of xerostomia. The conditioning intensity was a significant risk indicator in the development of xerostomia, while total body irradiation was not. Allogeneic HCT recipients experienced more xerostomia than autologous HCT recipients: a difference that could not be explained by a reduction in stimulated salivary flow rate or the development of oral mucosal changes related to cGvHD.