THE IMPACT OF VITAMIN D DEFICIENCY ON THE EFFICIENCY OF REHABILITATION MEASURES IN PATIENTS WITH ANKYLOSING SPONDYLITIS

Abstract

Low blood vitamin D concentrations are associated with the presence, risk of development, activity and more severe course of ankylosing spondylitis (AS). 58 patients with AS (males 62.1%, age 48[39;58] years) were examined to study the impact of vitamin D deficiency on the effectiveness of rehabilitation measures in the conditions of sanatorium-resort therapy. Determination (25-OH) vitamin D level, haematological indices SII (systemic immune-inflammation index; SII=number of platelets×number of neutrophils/number of lymphocytes) and SIRI (systemic inflammation response index; SIRI=number of neutrophils×number of monocytes/number of lymphocytes) were performed on arrival at the sanatorium and before discharge. The average BASDAI disease activity index was 3.0[2.4;3.5] points. Low activity of AS was determined in 31% and moderate activity in 69% of patients. Baseline Vitamin D levels were negatively correlated with pain intensity score (VAS, visual analog score) during walking (ρ=-0.44, p<0.001), and the association of these measures at discharge persisted but was less significant (ρ=-0.27, p=0.039). In the total group of AS patients, vitamin D deficiency (<20 ng/ml) was observed in 13.8%, and insufficient level (values in the range of 20-29 ng/ml) - in 25.9% of cases. In patients with normal (>30 ng/ml) and reduced (≤29 ng/ml) vitamin D levels, differences were noted for VAS (p=0.0025), ESR (p=0.040) and SIRI (p=0.046). All patients with AS were divided into two groups: I (n=26) - arrived for treatment from regions with low level of solar insolation; II (n=32) - arrived for treatment from regions with high level of solar insolation. At baseline, significantly lower vitamin D content was observed in AS patients in group I (p=0.040). A three-week stay and treatment in a sanatorium (an area with high solar insolation) demonstrated an increase in vitamin D levels (p=0.027) and a decrease in VAS pain intensity (p=0.017) only in group II patients. Of the inflammatory markers, only SIRI showed a significant decrease in group II patients with AS during treatment (p=0.038). The hematological index SIRI objectively reflects the dynamics of AS patients arriving for sanatorium-resort therapy from regions with different levels of solar insolation.