Non‐loading versus loading low‐dose colchicine in acute crystal‐associated arthritis: A double‐blinded randomized controlled study

Abstract

IntroductionThis study aimed to compare the efficacy of non‐loading versus loading low‐dose colchicine in patients with acute crystal‐associated arthritis.Materials and MethodsAll in‐patients who were admitted to Chiang Mai University Hospital with non‐arthritis disease and developed acute crystal‐associated arthritis during admission (within 48 h after arthritis onset) were invited to join this study. The patients were randomized into two groups. Patients in Group I (non‐loading group) and Group II (loading group) received colchicine at 1.2 and 2.4 mg in the first 24 h, respectively. The primary outcome was the patients' pain response at 24 h after treatment.ResultsOf 80 patients, 49 were acute gouty arthritis, and 31 acute calcium pyrophosphate (CPP) arthritis. The mean [95% CI] pain score was no different between Groups I and II at the baseline level (6.46[5.72–7.19] vs. 6.654[5.85–7.44], p = .867) and at 24 h (3.13[2.43–3.82] vs. 3.18[2.42–3.93], p = .907). The proportion of patients with ≥50% pain reduction was not different (57.50% vs. 55.00%, p = .822). Sensitivity analysis among patients with a baseline pain score of ≥4 showed the same pattern of response. Mild diarrhea was common and comparable in both groups. Subgroup analysis according to renal function (eGFR < 60 vs. ≥60 mL/min/1.73 m2) or type of crystals (acute gouty arthritis vs. acute CPP arthritis) also showed the same pattern of response.ConclusionNon‐loading low‐dose colchicine was as effective as loading low‐dose colchicine in patients with acute crystal‐associated arthritis, regardless of renal function or type of crystals.