Abstract and Introduction
Abstract
Background Knowledge about determinants of quality of life (QoL) in eosinophilic oesophagitis (EoO) patients helps to identify patients at risk of experiencing poor QoL and to tailor therapeutic interventions accordingly.
Aim To evaluate the impact of symptom severity, endoscopic and histological activity on EoE-specific QoL in adult EoE patients.
Methods Ninety-eight adult EoE patients were prospectively included (64% male, median age 39 years). Patients completed two validated instruments to assess EoE-specific QoL (EoO-QoL-A) and symptom severity (adult EoE activity index patient-reported outcome) and then underwent esophagogastroduodenoscopy with biopsy sampling. Physicians reported standardised information on EoE-associated endoscopic and histological alterations. The Spearman's rank correlation coefficient was calculated to determine the relationship between QoL and symptom severity. Linear regression and analysis of variance was used to quantify the extent to which variations in severity of EoE symptoms, endoscopic and histological findings explain variations in QoL.
Results Quality of life strongly correlated with symptom severity (r = 0.610, P < 0.001). While the variation in severity of symptoms, endoscopic and histological findings alone explained 38%, 35% and 22% of the variability in EoE-related QoL, respectively, these together explained 60% of variation. Symptom severity explained 18–35% of the variation in each of the five QoL subscale scores.
Conclusions Eosinophilic oesophagitis symptom severity and biological disease activity determine QoL in adult patients with eosinophilic oesophagitis. Therefore, reduction in both eosinophilic oesophagitis symptoms as well as biological disease activity is essential for improvement of QoL in adult patients. Clinicaltrials.gov number, NCT00939263.
Introduction
Since its first description 20 years ago, eosinophilic oesophagitis (EoO) is diagnosed increasingly often in Europe and the USA. An expert panel defined EoE as 'a chronic, immune/antigen-mediated, oesophageal disease characterised clinically by symptoms related to oesophageal dysfunction and histologically by eosinophil-predominant inflammation'. Most adult EoE patients suffer from dysphagia, but swallowing-associated pain and heartburn not responding to acid-suppressive medication can also occur.
Assessment of symptoms and biological measures are integral parts of patient care. Measures of clinical parameters and health-related quality of life (QoL) are accepted as important outcome indicators in clinical trials of therapeutic interventions in many chronic diseases. EoE has been described only two decades ago, as such, data on health-related QoL in adult and paediatric EoE patients are scarce. Van Rhijn et al. demonstrated that general health-related QoL [assessed by the short form health survey (SF-36)] in young adults with EoE was poorer than that in the same age category in a reference population. Other studies showed that QoL improved following treatment in both paediatric (assessed by paediatric QoL inventory) and young adult (assessed using the European organization for research and treatment of quality of life-oesophageal module 18 [EORTC QLQ-OES18] and SF-36) EoE patients. In 2011, Taft et al. published a novel, validated eosinophilic oesophagitis QoL (EoO-QoL-A) instrument for adult EoE patients. To date, no study using this instrument has been published.
Understanding the relationship between QoL, symptoms and biological findings as well as establishing determinants of QoL in adult EoE patient is important for defining outcomes for clinical trials and identifying patients at risk of experiencing poor QoL that may profit from therapeutic interventions. To date, there exist no data on determinants of QoL and the relationship between QoL, symptom severity and EoE-associated biological findings assessed by instruments validated for use in EoE. Therefore, this study aimed to evaluate the relationship between QoL (assessed by the EoO-QoL-A instrument), symptom severity [assessed by the adult Eosinophilic Esophagitis Activity Index (EEsAI) patient-reported outcome (PRO) instrument], EoE-associated endoscopic (assessed by EoE endoscopic reference score) and histological activity and to determine the main determinants of EoE-specific QoL in a well-defined population of adult EoE patients.