The association between Vitamin D Deficiency and Pulmonary Affection in Rheumatoid Arthritis Patients

INTRODUCTION

Rheumatoid arthritis (RA) is a systemic inflammatory disease that most typically affects the joints, producing progressive, symmetric, erosive destruction of cartilage and bone, and is often accompanied with autoantibody production. Extraarticular symptoms, such as pulmonary signs, are also linked to an increased risk of morbidity and mortality. They may even occur before articular symptoms. ¹

In rheumatoid arthritis, respiratory symptoms can be caused by a variety of conditions affecting the parenchyma, pleura, airways, or vasculature. Complications can occur as a result of rheumatoid arthritis or as a side effect of immune-suppressing medications used to treat rheumatoid arthritis. Within the first five years of disease, the bulk of respiratory signs arise. ²

Vitamin D may have a significant impact on both the innate and adaptive immune systems. The presence

of its receptors on several types of cells supports this, and its insufficiency is linked to the progression and result of RA. ³

According to a 2012 Greek study published in Therapeutic Advances in Endocrinology and Metabolism, vitamin D insufficiency is closely linked to disabling symptoms in people with rheumatoid arthritis. This could be because RA can impair the body's ability to absorb vitamin D from the foods we eat, and low vitamin D levels can exacerbate RA symptoms and pain. ⁴

Vitamin D reduces autoimmunity by modulating antigen-presenting cells' synthesis of pro-inflammatory and anti-inflammatory cytokines. A decrease in 25(OH) D3 is caused by polymorphisms in the vitamin D receptor and 1-hydroxylase genes, which may increase the risk of inflammation.⁵

The aim of the study to detect the prevalence of vitamin D deficiency and its relationship to pulmonary affection in RA patients and correlate it with disease Activity.

PATIENTS AND METHODS

The study was a cross sectional one, carried out on 50 patients diagnosed with RA recruited from the Chest and Rheumatology Outpatient Clinics of Al Hussein University Hospital in period between August 2021 and May 2022.

Ethical Considerations: The selection of subjects done after prior explanation of the aim of the study, and a free-will written approval consent is taken, and the whole work done according to the ethical committee, Faculty of medicine, Al-Azhar University

Inclusion criteria include: All patients diagnosed with RA who fulfilled the American Colleague of Rheumatology/European League against Rheumatism 2010 classification criteria.

Exclusion criteria include: No specific contraindications.

All studied patients are subjected to: Detailed history taking. Physical examinations, Laboratory investigations were performed including complete blood count, erythrocyte sedimentation rate (ESR), C-reactive protein titer, liver enzymes, and renal function tests. Rheumatoid factor (RF) titer was determined using the latex agglutination test kit and anti-CCP antibody titer using the ELISA technique, serum 25-hydroxy vitamin D [25(OH) D] levels was performed using ELISA, Chest x-ray, High Resolution Computed Tomography( HRCT) Chest, and Spirometry      Statistical analysis:The Statistical Program for Social Science (SPSS) version 24 was used to examine the data. The mean and standard deviation were used to express quantitative data. Frequency and percentage were used to express qualitative data. The central value of a discrete set of numbers, namely the sum of values divided by the number of values, is called the mean (average). The standard deviation (SD) is a measure of a set of values' dispersion. A low SD implies that the values are spread out over a wider range, whereas a high SD shows that the values are close to the set's mean. When comparing non-parametric data, the Chi-square test was utilized. To compare quantitative data on vitamin D levels, the Kruskal Willis test was utilized. For data correlation, the Pearson correlation coefficient was applied. P-values less than 0.05 were considered significant, P-values less than 0.001 were regarded very significant, and P-values more than 0.05 were considered inconsequential.

RESULTS

Table 1: Description of demographic data in all studied patients

The result of our study showed that the description of demographic data in all RA patients with pulmonary affection shown that the mean age of all studied patients was 46.7 ± 6.6 years with minimum age of 38 years and maximum age of 61 years. As regard duration, the mean duration of all studied patients was 13.9 ± 5.6 years with minimum duration of 1 year and maximum duration of 23 years. As regard sex, there were 10 males (20%) and 40 females (80%) in the studied patients. As regard smoking, there were 5 smokers (10%) and 45 non-smokers (90%) in the studied patients. Table (1)

Table 2:Vitamin D serum level in all studied patients. 

In our study, the description of vitamin D status in all studied patients were 22 deficient patients (44%), 22 insufficient patients (44%) and 6 sufficient patients. Table (2)

Table 3: Description of CT chest findings in all studied patients

As regard CT pattern of interstitial lung affection, the most common pattern was NSIP in 24 patients (48%), UIP in 17 patients (34%) and RB-ILD in 9 patients (18%). Table (3)

Table 4:The correlation between vitamin D level and DAS- 28 score

 DAS-28 (disease activity score) and 28 mention to the count of peripheral joints examined for tenderness in rheumatoid arthritis patient

In all patients, A relationship is present between vitamin D level and DAS-28 in Vit-d deficient patients, study found a significant (p-value = 0.002) rise in DAS-28 score.(5.4 ± 0.8) when compared with insufficient patients (4.9 ± 0.4) and sufficient patients (4.1 ± 0.8). Table (4)

Table 5: Relation between vitamin D status and clinical manifestations in all studied patients

In our study there no statistically significant relation (p-value < 0.05) between vitamin D status and clinical manifestations (Exertional Dyspnea, Dry Cough, Chest Pain, Wheezing and Leathery Crepitation). Table (5)

Table 6: Relation between vitamin D status and Spirometric indices in all studied patients

There is significant decrease in FVC (p-value < 0.001)  in Vit-D deficient patients (89.3 ± 20.1) when compared with insufficient patients (113.4 ± 7.1) and sufficient patients (114.8 ± 3.4). No significant difference  (p-value > 0.05) in  vitamin D status and FEV1 & FEV1/FVC. Table (6)

Table 7: Relation between vitamin D status and PFTs pattern in all studied patients

The study shows that there was statistically significant difference  between vitamin D deficient patients, insufficient patients, and sufficient patients as regard PFTs pattern. Table (7)

Table 8: Relation between vitamin D status and CT findings in all studied patients

In our study there was no significant difference  between vitamin D status and the following CT findings (reticulations, pleural effusion, pleural thickening, sub-pleural cysts and GGO). Statistically significant (p-value = 0.012) increased percentage of nodule in deficient patients (12 patients, 54.5%) and insufficient patients (15 patients, 68.2%) when compared with sufficient patients (0 patients, 0%). Highly statistical significant (p-value < 0.001) increased percentage of emphysema in deficient patients (12 patients, 54.5%) when compared with insufficient patients (0 patients, 0%) and sufficient patients (0 patients, 0%). Highly statistical significant (p-value < 0.001) increased percentage of honey combing in deficient patients (12 patients, 54.5%) when compared with insufficient patients (1 patient, 4.5%) and sufficient patients (0 patients, 0%). Highly statistical significant (p-value < 0.001) increased percentage of Bronchiectasis in deficient patients (22 patients, 100%) when compared with insufficient patients (8 patients, 36.4%) and sufficient patients (0 patients, 0%). Table (8)