Background Renal dysfunction is common in gout and occurs due to various combinations of hyperuricemia, comorbidities (hypertension, atherosclerosis, diabetes), and medication (NSAIDs, allopurinol). In these conditions, the medication should be safe for kidneys. However, primary care general practitioners (GP) tend to prescribe high doses of NSAIDs in gouty arthritis that could lead to renal insufficiency, especially in case of a relatively long term treatment.
Objectives To assess treatment of gouty arthritis administrated by GP and to determine changes in the renal function.
Methods 100 patients enrolled with acute gouty arthritis fulfilled ACR 1977 classification criteria for acute gouty arthritis. 83% of patients were males with the mean age of 57,5 years and average disease duration of 8,8 years. Comorbidities included hypertension (77%), ischemic disease (7%), chronic cardiac failure (15%), diabetes (21%), and renal calculi (33%). 33 patients received Allopurinol 100-300 mg/day and 3 patients received 600 mg/day. Patients were given a short half-life NSAIDs prescribed by GP. Preferred NSAID was Diclophenac taken by 61% of patients at a daily dose of 175 mg or 200 mg. An average duration of treatment in primary care was 17 days. The treatment goal was not achieved, and the patients were admitted to the Rheumatology Unit. Changes in GFRs and also the factors decreasing renal function were studied during the follow-up.
Results Maximal doses of NSAIDs were prescribed to 97 patients including 15 patients with GFRs <60 ml/min. 47 patients continued the same dosing within the treatment period. After NSAIDs treatment, 47% of patients had increased GFRs (86,8 vs 102,6, ml/min, p>0,05), the number of patients with GFRs <90 ml/min diminished from 28 to 19 (p=0,063). 53% of patients had decreased GFRs (95,8 vs 78,1 ml/min, p<0,05), the number of patients with GFRs less than 90 ml/min raised from 27 patients at the beginning of treatment to 39 patients after NSAIDs treatment (p=0,016). The number of patients taking high doses of NSAIDs during the treatment period was higher in the group with negative changes in GFRs (OR-2,73; 95%CI, 1,73 to 4,32; p=0,015). Comparing various features of these groups, we found that cases of infection making 20,8% (pneumonia 1, bronchitis 2, pyelonephritis 3, suppurrated tophis 5) (OR-9,75, 95%CI, 1,3-72,96; p=0,012) and symptoms of nhronic heart failure (OR-4,88; 95%CI 1,13 to 21; p=0,038) probably due to NSAIDs were more frequent in group with reduced GFRs.
Conclusions In primary care, NSAIDs are preferred drugs for treating acute gouty arthritis. They are even prescribed in pre-existing renal insufficiency. The results of the study suggest that renal function during acute gout attack can improve or worsen. High doses of NSAIDs can produce a negative effect on renal function during the treatment period because of concomitant infections and chronic heart failure.
Disclosure of Interest None Declared