Clinical aspects and potential biomarkers in dry mouth and dry eye disease

Abstract

Dry mouth and dry eyes are common findings, especially in subjects on multiple medications. Primary Sjögren's syndrome (pSS) also causes dry mouth and dry eyes, and radiotherapy due to head and neck cancer (HNC) is known to lead to dry mouth. The aims of this thesis were to investigate possible relationships between dry mouth and dry eyes, evaluate clinical outcomes and explore saliva and tear biomarkers. The studies included HNC patients treated with radiotherapy, young elderly subjects and patients with pSS. The studies demonstrated a previously non-identified connection between dry mouth and dry eyes in both HNC and young elderly subjects. As expected, HNC patients were severely bothered by dry mouth, but symptoms of dry eyes were common in both groups. Differentially expressed cytokines, metabolites and proteins were identified in HNC and pSS patients. Overall, the findings underline the need for cooperation between various health professions. Moreover, detailed investigations of saliva and tears may improve the understanding of disease mechanisms behind dry mouth and dry eyes, hopefully leading to better patient care in the future.