Prevalence of subclinical peripheral neuropathy in rheumatoid arthritis patients in Eastern India: A hospital based clinical study

Abstract

Background: It is difficult to diagnose the slight or early neuropathy and study of peripheral nervous system is often made difficult by symptoms resulting from pain in the joints in the patients with rheumatoid arthritis (RA). Therefore inclusion of electro-neuro-physiological examination of the RA patient is usually carried out in routine diagnostic procedure. Taking all these in consideration, the aim of our study was to detect subclinical neuropathy by electrophysiological testing in RA patients from Eastern India.Materials & Methods: This was a type of cross-sectional study which was undertaken to show the prevalence of subclinical neuropathy in patients of RA. This study was conducted over a period 18 months in the Rheumatology out-patient department. The technique employed was systematic sampling method. Fifty one patients between 35 to 79 years comprising of 44 females and 7 males were enrolled for the study in the first 12 months and then subsequently followed up for 4 visits at an interval of 6 weeks up to another 6 months. Patients were selected on the basis of confirmation of RA as per the American Rheumatological Association/ ARA revised criteria 1987.Results: The prevalence of subclinical peripheral neuropathy is more than 1/3rd of the rheumatoid patients. The neuropathy has definite relationship with RF positivity and high titres of anti CCP antibody. It also showed significant correlation with the disease duration, a sharp rise in ratio between neuropathy present and neuropathy absent groups after around 6 years of the disease. It did not show any significant correlation with age, sex, disease activity index. Fisher exact test P value= <0.0001, statistically significant association between Anti-CCP and presence of sub-clinical neuropathy. Conclusion: The prevalence of subclinical peripheral neuropathy is more than 1/3rd of the rheumatoid patients. Electrophysiological studies can diagnose subclinical peripheral neuropathy at a quite early stage. A very small percentage of patients developed overt clinical neuropathy, when followed up over a very small period of time of 6 months. The neuropathy has definite relationship with RF positivity and high titres of anti CCP antibody.

Keywords: Rheumatoid arthritis, peripheral neuropathy, rheumatoid factor, anti– CCP titre, electrophysiological testing.