Lung function is associated with minimal EQ-5D changes over time in patients with systemic sclerosis

Clinical Rheumatology, vol. 39, pp. 1543–1549

Abstract

In systemic sclerosis (SSc) therapeutic efforts are often directed to prevent progressive respiratory impairment, but it is unclear to what extent changes in pulmonary function tests (PFTs) are associated with health-related quality of life (HRQoL). The aim of our study is to evaluate how modifications in PFTs contribute to longitudinal variations in HRQoL, assessed through the multidimensional questionnaire EQ-5D, in patients with SSc. We included SSc patients with forced vital capacity (FVC%), diffusing capacity of the lungs for carbon monoxide (DLCO%) and EQ-5D assessed in at least two visits. The EQ-5D consists of two parts, a utility score ranging from - 0.59 to 1, and a 0-100 Visual Analogue Scale (VAS). Higher values represent better health. The association between changes in FVC% and DLCO%, and evolution of EQ-5D over time, was investigated using generalized estimating equations. Three hundred seventy-eight patients were included, accounting for a total of 1619 measurements. The models showed that improvement in FVC% is significantly associated with increase in both utility score (β = 0.001; 95% CI 0.000 to 0.002; p = 0.003) and VAS over time (β = 0.188; 95% CI 0.111 to 0.264; p < 0.001). Moreover, improvement in DLCO% is longitudinally associated with increase in utility score (β = 0.001; 95% CI 0.000 to 0.002; p = 0.038), while the results for VAS were non-significant (β = 0.020; 95% CI -0.079 to 0.120; p = 0.690). We show that change in PFTs has a significant, although minor, impact on HRQoL as measured by EQ-5D in SSc.Key Points• In patients with SSc, changes in PFTs have a significant, although minor, impact on HRQoL.• In patients with SSc-ILD, the perception of HRQoL is nearly not influenced by changes in pulmonary function.• The use of generic questionnaires might not be sensitive enough to evaluate the impact on quality of life of therapies targeting specific SSc manifestations.

Authors 6

1. Jacopo Ciaffi corresponding Aachen Department of Rheumatology, Leiden University Medical Center

   University of Modena and Reggio Emilia · Leiden University Medical Center · Azienda Ospedaliero-Universitaria di Modena · Istituto Ortopedico Rizzoli

   Affiliation as printed

   Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands. j.ciaffi@lumc.nl

   Medicine and Rheumatology Unit, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy. j.ciaffi@lumc.nl

   Rheumatology Unit, Azienda Policlinico of Modena, University of Modena and Reggio Emilia, Modena, Italy. j.ciaffi@lumc.nl

   Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands

2. Nina Marijn van Leeuwen Aachen Department of Rheumatology, Leiden University Medical Center

   Leiden University Medical Center

   Affiliation as printed

   Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands

3. Sophie I E Liem Aachen Department of Rheumatology, Leiden University Medical Center

   Leiden University Medical Center

   Affiliation as printed

   Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands

4. Maarten K. Ninaber Aachen Dept of Pulmonology, Leiden University Medical Center

   Leiden University Medical Center

   Affiliation as printed

   Department of Pulmonology, Leiden University Medical Center, Leiden, the Netherlands

5. Tom W. J. Huizinga Aachen Department of Rheumatology, Leiden University Medical Center

   Leiden University Medical Center

   Affiliation as printed

   Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands

6. Jeska Kirsten De Vries-Bouwstra Aachen Department of Rheumatology, Leiden University Medical Center

   Leiden University Medical Center

   Affiliation as printed

   Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands