The Association Between Smoking and Clinical and Radiological Severity in Patients with Primary Knee Osteoarthritis: The First Cross-sectional Study in Syria

Abstract

Abstract Background: Osteoarthritis (OA) is a prevalent disease and a primary cause of disability globally. The most often impacted joints by OA are the knees. Furthermore; Smoking is a prevalent social behavior that has been linked to many illnesses. The purpose of this research is to ascertain whether smoking and knee OA are related in Syria. Methods: A cross-sectional study was conducted on 236 patients with primary knee OA who met the American College of Rheumatology (ACR) diagnostic criteria. Exclusion criteria encompassed various secondary diseases. Detailed smoking behavior and general demographic features were assessed. The clinical characteristics of OA were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the radiological severity was assessed using Kellgren and Lawrence (KL) grades for each patient. The sample size was determined using Cochran's formula, and statistical analysis was performed using SPSS 25, including chi-square tests, ANOVA, and linear correlation coefficients to assess relationships between variables. Results: The majority of OA patients (67.4%) were never smoking, which was followed by current smokers (27.1%) and former smokers (5.5%). There was no correlation between smoking status and total Womac, pain, stiffness, physical function, or radiographic severity, with p-values of 0.552, 0.437, 0.640, 0.796, and 1.109, respectively. The overall Womac score showed a significant gender difference (p-value = 0.002), with females showing an increase of 8.48 points over males. A correlation was found between average daily smoking, BMI, and gender, with p-values of 0.004 and 0.001, respectively. The difference in BMI was significant only between heavy smokers and never-smokers, with a difference of 3.54 (p-value =0.001) Conclusion: In individuals with osteoarthritis, there was no significant correlation between cigarette smoking and radiological results; nevertheless, there was an inverse relationship with mean WOMAC scores (smokers have lower WOMAC scores than never-smokers). It seems implausible that smoking actually prevents the progression of OA, even though it was found to be negatively correlated with the disease's progression either clinically or radiologically in the analysis. It will need further research to identify the mechanism behind this correlation.