Correlation Between The Level Of 1,25-dihydroxy Vitamin D₃ And Pulmonary Arterial Pressure And Cardiovascular Risk Factors In Rheumatoid Arthritis

BackgrondRheumatoid arthritis?RA?is a systemic autoimmune disease,characterized by chronic,symmetric and invasive arthritis.In addition to joints,it can involve multiple organs such as skin,eyes,kidneys,lungs and heart.Pulmonary arterial hypertension?PAH?is a serious complication of RA.Progressive PAH can lead to heart failure,respiratory failure and so on.An easily overlooked type,is associatedwith rapid progression and poor prognosis.RA patients also have a kind of cardiovascular risk factor,and this factor is not a traditional cardiovascular risk factor.Vitamin D receptors are widely found in a variety of tissues,such as vascular smooth muscle cells,endothelial cells,and cardiac myocytes.The main circulation form of vitamin D is achieved by 1,25-dihydroxyvitamin D₃?1,25?OH?₂D₃?.The serum levels of 1,25?OH?₂D₃ is often measured to reflect the levels of vitamin D.ObjectiveTo investigate the correlation between the levels of 1,25-dihydroxy vitamin D₃?1,25?OH?₂D₃?and pulmonary arterial pressure and cardiovascular risk factors in patients with RA,and to explore its significance.MethodsThree hundred patients with RA from September 2015 to December 2016 in Department Rheumatology of the Second Hospital of Shanxi Medical University were enrolled in the study,and divided into simple RA group?n=213?,pulmonary involvement group?n=67?and cardiovascular involvement group?n=20?.Clinical and laboratory features such as age,gender,disease duration,disease activity?DAS 28?,erythrocyte sedimentation rate,1,25?OH?₂D₃ level,pulmonary arterial pressure and cardiac function index were recorded in detail.Numerical data and categorical data were compared using t test and the correlation of 1,25?OH?₂D₃ level and pulmonary arterial pressure was assessed using linear regression analysis.ResultsPulmonary arterial pressure in RA patients with pulmonary involvement?29.09±11.35 mmHg?was significantly higher than that in simple RA?23.48±8.84 mm Hg??t=-2.573,P=0.013?.However,there was no significant difference in pulmonary arterial pressure between cardiovascular involvement group?28.75±9.09 mmHg?and simple RA group?P=0.079?.The levels of 1,25?OH?₂D₃ were all deficient among simple RA group,RA with pulmonary involvement group and RA with cardiovascular involvement group,but showed no difference among three groups.The levels of 1,25?OH?₂D₃ was negatively correlated with pulmonary arterial pressure?r=-0.217,P<0.05?.Further grouping,significant inverse relationship were observed between the levels of 1,25?OH?₂D₃ and pulmonary arterial pressure in RA with pulmonary involvement group?r=-0.447,P<0.05?,but not in RA with cardiovascular involvement group or simple RA group.There were 20cases of RA with cardiovascular disease,including 11 cases of arrhythmia,5 cases of coronary heart disease,2 valvular diseases,1 atrial septal defect and 1 pericardial effusion.Compared with simple RA patients,there were no significance among ejection fraction,cardiac output,and per stroke output,CK?CKMB?LDH?HBDH?CHOL?TG?LDL?t=0.353,0.641,0.646,0.510,0.062,0.943,0.662,0.377,0.648,0.307,P all>0.05?.There was a significantly negative correlation between the level of 1,25?OH?₂D₃ and HBDH in patients with RA?r=-0.341,P<0.05?.Although there was a negative correlation between1,25?OH?₂D₃ and TG or LDL,the difference was not statistically significant?P>0.05?.ConclusionThe level of 1,25?OH?₂D₃ has a close relationship with pulmonary arterial pressure in patients with RA,especially combined with pulmonary involvement.The level of1,25?OH?₂D₃ is not associated with the risk factors of cardiovascular disease,to a certain extent.