Micronutrients deficiencies in patients with spondylarthritis: the potential immunometabolic crosstalk in disease...

Micronutrient deficiencies (MNDs) are common among patients with certain chronic inflammatory diseases. They are associated with a pro-inflammatory status and co-morbidities. However, no studies have specifically investigated MNDs in Spondyloarthritis (SpA). This paper aimed at analyzing the occurrence of anemia and deficiencies of ferritin (Fe), vitamin D [25(OH)D], vitamin B12 (B12), and folic acid (FA) in SpA patients. The interplay of MNDs with age, gender, and metabolic abnormalities was also explored.

MNDs were evaluated in 220 SpA outpatients (137 females and 83 age-matched males) with psoriatic arthritis (PsA, n=110) and non-psoriatic SpA (n=110). Metabolic parameters were analyzed. Disease activity was assessed by either Disease Activity in PSoriatic Arthritis (DAPSA) or Ankylosing Spondylitis Disease Activity Score with C-Reactive Protein (ASDAS-CRP) as appropriate, while the functional status was evaluated using Health Assessment Questionnaire modified for SpA (HAQ-S).

Anemia occurred in 13.6% of subjects of the study cohort and almost wholly in females (p=0.004). Females showed higher Fe deficiency (p=0.04) and lower Fe levels (p=0.0003) than males. Hemoglobin (Hb) resulted inversely related to age and CRP (p=0.01 and p=0.008) in male group. The 25(OH)D deficiency (≤20 ng/ml) was present in 23.2% of the cohort with a higher prevalence in males than females (p=0.02): moreover, 25(OH)D inversely correlated with disease duration (p=0.02) in males. The B12 deficiency (≤200 pmol/l) was rare (13.2%), while FA ≤4 ng/ml was frequent (22%) and associated with B12 deficiency in 31% of cases. SpA patients in moderate/high disease activity had higher Body Mass Index (BMI) (p=0.04) and HAQ-S (p<0.0001), as well as lower Hb (p=0.02), and Fe (p=0.03) than patients in remission/low disease activity (LDA). In patients with extra-articular manifestations, female sex was prevalent (F:M=2) and B12 levels were lower than in patients without (p=0.005). Interestingly, 25(OH)D was lower (p=0.04) and both BMI and HAQ-S (p=0.036 and p=0.01) were higher in patients without extra-articular involvement than patients with.

Our findings documented a relevant prevalence of MNDs in SpA patients, and its strict interplay with gender and metabolic abnormalities by highlighting the role of MNDs in inflammatory-dependent dysmetabolism in SpA.