Patients and methods: 35 patients with clinical and radiological evidence of knee OA (average age of 58.8 years) were recruited for this study. Patients with hypertension, diabetes, patients on vitamins and those with other intercurrent infections were excluded. 20 apparently normal adults (average age of 53.3 years) who had no clinical evidence of OA were used as controls (The radiographs of their knees were not taken either). Informed consent was obtained from both the patients and the control group. 5mls of venous blood was taken from the cubital fossa. Serum total antioxidant status (TAS) was estimated using the technique described by Koracevic et al.
Results: The mean TAS in the osteoarthritic subjects was 1.09 ± 0.38mmol/l while the value for the control was 1.6 ± 0.09mmol/l (P<0.05). The arthritic patients also had a higher body mass index (BMI).
Conclusion: The TAS values obtained in this study are a dynamic equilibrium of the antioxidative defence system of the body and not a simple sum of the activities of the various antioxidants. In this study, lower TAS may be due to the increase utilisation of antioxidants in the presence of free radicals which may be incriminated in the pathogenesis of osteoarthritis, but it may well be due to lower dietary intake of these protective substances from natural sources.