Relationship between optimism and quality of life in patients with two chronic rheumatic diseases: axial spondyloarthritis and chronic low back pain: a cross sectional study of 288 patients

BACKGROUND: Axial Spondyloarthritis (AxSpA) and chronic low back pain are rheumatic diseases that impact patients’ health-related quality of life (HRQoL). In other chronic conditions, HRQoL was positively associated with dispositional optimism, a personality trait. The objective was to explore the relationship between optimism and HRQoL in these two diseases. METHOD: A cross-sectional study was performed in 2 tertiary care hospitals and 2 private practices in France. Patients had definite AxSpA or chronic low back pain according to the rheumatologist. A generic HRQoL questionnaire (Short Form, SF-12) with physical and mental composite scores (PCS and MCS respectively) and an optimism questionnaire (the Life Orientation Test-revised, LOT-R) were collected. Analyses included non-parametric correlations and multiple regression analyses to study the effect of optimism on PCS and MCS. RESULTS: In all, 288 (199 AxSpA and 89 low back pain) patients were included: mean age, 47.3 ± 11.9 years, 48.6 % were males. Pain levels (0–10) were 4.5 ± 2.4 and 4.3 ± 2.4 in AxSpA and LOW BACK PAIN patients, respectively. HRQoL was similarly altered in both diseases, for both physical and mental composite scores (mean PCS: 43.7 ± 8.2 vs. 41.9 ± 7.1; mean MCS: 45.9 ± 7.8 vs. 46.7 ± 8.1 for AxSpA and low back pain respectively). Optimism was moderate and similar in both populations. Optimism was positively correlated to MCS in both diseases (rho = 0.54 and 0.58, respectively, both p <0.01) and these relations persisted in multivariate analyses (beta = 1.03 and 1.40, both p <0.0001). CONCLUSIONS: Optimism was similar in these 2 chronic diseases and was an explanatory factor of the mental component of HRQoL, but not physical HRQoL. Physical HRQoL may reflect more the disease process than character traits. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12955-015-0268-7) contains supplementary material, which is available to authorized users.