Epidemiology of analgesic nephropathy in Belgium.

The incidence of analgesic nephropathy in patients with terminal renal failure (AN-TRF) was evaluated by questioning all the dialysis units in Belgium. The results were analyzed with respect to the distribution of the analgesic market in Belgium. Replies were received from 46 of the 49 dialysis units for adults. Of the 1,400 patients treated in these units, 258 (18.4%) have AN. Furthermore, AN was more frequent in the neighbourhood of Antwerp than in the other Belgian provinces (100 AN-TRF/million adults vs 19; 36% of TRF vs 14%, P less than 0.001). The number of patients treated by hemodialysis per million adults was correlated well with the number of AN-TRF/million adults in the various areas of Belgium (r = 0.73, P less than 0.05). 265 tons of analgesics (35 g/adult/year), including 55 tons of phenacetin (7 g/adult/year) are sold each year in Belgium. Among the five most popular drugs in Belgium, three are analgesics containing acetylsalicylate-phenacetin or phenazone or paracetamol-caffeine. These three analgesics are made in the neighbourhood of Antwerp, no such analgesics are made in other areas of Belgium. No correlation exists between the geographic distribution of AN-TRF and the distribution of other widely-used over-the-counter drugs such as laxatives, non-phenacetin-containing analgesics and even analgesics which contain phenacetin but which are not made in Belgium. Conversely, the distribution of AN-TRF was well correlated with that of the sale of an analgesics made in the neighbourhood of Antwerp (r = 0.79, P less than 0.001). Belgium thus has, after Australia, the second highest incidence of analgesic nephropathy in the world. The geographic distribution of AN-TRF inside Belgium correlates with the existence of analgesic factories in the neighbourhood of Antwerp.