Decreased Plasma Vitamin D Levels in Patients with Undifferentiated Spondyloarthritis and Ankylosing Spondylitis

Abstract

Objective The aim of the present study was to evaluate the plasma vitamin D (vit D) levels and their association with the disease activity in patients with ankylosing spondylitis (AS) and undifferentiated spondyloarthritis (uSpA) compared with healthy populations. Methods This study included 161 spondyloarthritis patients (113 uSpA patients and 48 AS patients) attending our rheumatology out-patient clinic, along with 92 controls. Results The plasma vit D levels were 18 μg/L (8-38) in the AS group, 20 μg/L (4-92.3) in the uSpA group and 24.3 μg/L (7.2-76.8) in the control group. The plasma vit D levels of the AS patients were significantly lower than those of the patients in the control group (p=0.004). The men in the AS group had significanly lower vit D levels than those in the control group (p=0.005). On the other hand, the women in the uSpA group had significanly lower vit D levels than those in the control group (p=0.011). The vit D levels were inversely related to both erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in the AS patients (p=0.002, R=-0.428; p<0.001, R=-0.592, respectively). This correlation was not demonstrated in the uSpA patients. The vit D levels were not found to correlate with the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) levels in either the AS or uSpA patients. Conclusion 25-hydroxy-vit D deficiency is frequently observed in patients with SpAs. In this study, vit D deficiency was much more prominent in the male AS patients. On the other hand, among women, the uSpA patients exhibited much more prominent vit D deficiency than the control group subjects. The acute phase response may inversely affect the vit D levels in AS patients.

Correlation of Vitamin D Deficiency and Sub-Clinical Osteomalacia in Axial Spondyloarthropathy.

“…However, in the early phases of osteomalacia biochemicals such as calcium, phosphate and soluble phosphatase are released in serum because of a low 25(OH)D level, may be lacking due to compensatory changes conversely the PTH may be lifted and it lead to decalcification of the skeleton . AS patients are associated with low vitamin D in serum concentrations are linked with higher disease activity [15]. Although vitamin D concentrations were not associated with higher disease activity in our study, vitamin D levels were significantly lower in axSpA patients.…”

Nutritional aspects and vitamin D supplementation in ankylosing spondylitis

“…While several studies had shown the aggravating effect of vitamin D's deficiency in the activity markers of AS disease [61][62][63][64] , other studies have not found any correlation [65][66][67] . Although, there is evidence for increased risk of AS in people with deficiency of vitamin D [68][69][70] further studies are required to clarify the causal relationship between the deficiency of vitamin D and activity of AS disease.…”

“…In a study of 48 AS patients has been reported a significant correlation between plasma 25(OH)D levels and erythrocyte sedimentation rate (ESR)/CRP, but did not observe any significant correlation with BASDAI 61 . Hmamouchi et al showed that there is a significant inverse correlation between 25(OH)D and Bath AS Functional Index (BASFI)/BASDAI adjusted to gender and age 62 .…”

Vitamin D Levels in Patients With Ankylosing Spondylitis and Its Relationship With Disease Activity

“…Therefore, factors affecting the immune system may have effects on the disease course. One of these factors affecting the immune system is vitamin D. 2 The relationship between serum vitamin D levels and disease activity scores in patients with AS has been studied in a number of studies [3][4][5] with varying results. Based on this controversy, we aimed to elucidate the relationship between serum vitamin D levels and disease activity scores in AS patients as well as to compare vitamin D levels of AS patients with healthy individuals.…”

“…There was no significant correlation between vitamin D levels and BASDAI scores (r= -0.035, p=0.765). Although the relationship between serum vitamin D levels and disease activity in AS has been studied in a number of studies, [3][4][5] only one study showed a relationship between 25-OH-D levels and disease activity. 4 Lange et al 5 reported a correlation between disease activity in AS and 1,25-OH-D metabolites levels; however, not with 25-OH-D. We used 25-OH-D which is the major circulating form of vitamin D.…”