Patient burden of Sjögren's: a comprehensive literature review revealing the range and heterogeneity of measures used in assessments of severity

Abstract

Context: The severity of Sjögren's syndrome has been evaluated using a wide variety of clinical measures and patient-reported outcomes (PROs). This may contribute to the lack of clarity concerning the burden of Sjögren's from the patient perspective.

Objective: To perform a comprehensive peer-reviewed literature analysis of the patient aspects of Sjögren's, focusing on PROs, to investigate the complexity underlying the evaluation of the syndrome and to elucidate the discordance between the different measures.

Methods: We searched Embase for articles published between January 2005 and September 2015. Research articles, clinical and diagnostic reviews, and validation studies with a focus on patient aspects of Sjögren's were selected as the primary information source.

Results: 157 articles met the eligibility criteria. A wide variety of assessment measures used to evaluate glandular, extraglandular and functional domains were observed. Many different, non-validated Visual Analogue Scales, with a wide range of anchor words, were used in the quantification of Sjögren's disease burden, impeding comparisons between studies. Relatively few clinical trials of drug therapies used validated scales: European League Against Rheumatism Sjögren's Syndrome Patient Reported Index was used most often for symptom assessment and 36 Item Short Form Survey for quality of life (QoL).

Conclusion: A wide range and diversity of measures are used to evaluate the patient burden of Sjögren's; most are not validated for use in this disease. PRO endpoints, validated specifically in Sjögren's, that demonstrate improvement are needed. These measures should focus on QoL aspects important to patients and will most likely involve gauging change in function rather than patient-reported symptoms.

Keywords: Outcomes Research; Patient Perspective; Quality of Life; Sjögren’s Syndrome.

Figure 1

Flow diagram of Embase searches.

Figure 2

Most commonly used PRO scales across Sjögren’s drug therapy trials. ESSPRI, European League Against Rheumatism Sjögren’s Syndrome Patient Reported Index; MFI, Multidimensional Fatigue Inventory; PRO, patient-reported outcome; PROFAD, Profile of Fatigue and Discomfort; SF-36, 36 Item Short Form Survey; VAS, Visual Analogue Scale.