FVC, FEV1 and FEV1/ FVC % in Rheumatoid Arthritic Female and their Relationships with Duration of the Disease

Abstract

Background: Rheumatoid Arthritis (RA) is the most common inflammatory disorder mediated throughthe immune system, affecting joints and various organs including lungs. Pulmonary dysfunction inRA patients has been reported. Objective: To observe FVC, FEV1 and FEV1/ FVC % in female patientsof RA and their relationships with duration of the disease. Methods: This cross-sectional study wascarried out in the Department of Physiology, BSMMU, Dhaka, from January to December 2009 on 90RA female patients of 30-50 years age (Group B). For comparison, 30 age and BMI matched apparentlyhealthy subjects (Group A) were also studied. According to the duration of disease, RA patients weresubdivided into B1 (newly diagnosed), B2 (3-5 years ) and B3 (6-10 years ). They were selected from theOut Patient Department of Physical Medicine of Bangabandhu Sheikh Mujib Medical University,Dhaka. FVC, FEV1 and FEV1/FVC% of all the subjects were measured by a digital MicroDL spirometer.Results were expressed as percent of predicted value. For statistical analysis One-Way ANOVA,Unpaired Student's 't' test and Pearson's correlation coefficient test were performed, as required.Results: The mean percentage of predicted values of these lung function parameters in the healthyfemale subjects and newly diagnosed (B1) RA patients were within normal ranges. The mean percentageof predicted values of all the spirometric variables were significantly lower in the patients in B3compared to those in B2 (FVC p<0.01, FEV1 p<0.01), B1 (FVC p<0.05, FEV1 p<0.05, FEV1/FVC% p<0.001) and A (FVC p<0.01, FEV1 p<0.001, FEV1/FVC% p<0.001), except FEV1/FVC% in B3 vs B2 whichwas lower but nonsignificant. Again these same parameters were significantly lower in B2 in comparisonto B1 (FVC p<0.001, FEV1 p<0.001, FEV1/FVC% p< 0.001) and A (FVC p<0.001, FEV1 p<0.05, FEV1/FVC% p<0.001). In addition all the ventilatory variables had significant (p<0.001) negative correlationwith durations of disease except FVC in B1, which was significant at p<0.01 level. Conclusion: Thisstudy reveals that pulmonary functions may be lower in patients of RA and the lung function isinversely related to the duration of disease.Key Words: FVC; FEV1; Rheumatoid ArthritisDOI: 10.3329/jbsp.v5i1.5412J Bangladesh Soc Physiol. 2010 June; 5(1): 8-13