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Possible relation between restless legs and anaemia in renal dialysis patients SIR,--One of the
Fig 1-Typical "P-MR spectra obtained at rest from calf muscle of MH susceptible (L) and non-susceptible (R) subject. PME=phosphomonoesters; Pi=inorganic phosphate; PDE= phosphodiesters; truncated peaks are PCr=phosphocreatine, ATP=adenosine triphosphate; ppm=parts per million.
most troublesome and difficult to treat of is uraemia restless legs. The pathophysiology is not symptoms known, but has been related to peripheral neuropathy in uraemic patients1 and to anaemia and iron deficiency in others.2 We have evaluated patients on chronic haemodialysis and peritoneal dialysis for clinical and biochemical associations of restless legs and for the effect of correction of anaemia with epoetin alfa. 55 patients (22 male, mean age 53 [SEM 2] years, mean duration of dialysis 37 [6] months) receiving either haemodialysis (n 34) or continuous ambulatory peritoneal dialysis (21) were assessed. Restless legs was graded according to severity (4 = severe, intolerable affecting sleep; 3 annoying, every day; 2 moderate, more than once a week; 1 = mild, not more than once per week; 0 = none). 22 patients (40 %) had restless legs. It was more common in women than in men (p 0-03), and was related to time on dialysis (long vs short time, p < 0-01). Patients with restless legs had a lower haemoglobin than those who did not (82 [4] vs 95 [4] g/l, p 0-03). Age, type of dialysis, and serum biochemistry (including electrolytes, urea, creatinine, calcium, phosphorus and magnesium) did not differ between those who had restless legs and those who did not. There was no relation between the presence or severity of the restless legs syndrome and clinical evidence of peripheral neuropathy, or its severity, as assessed clinically by grading of any vibration sense and tendon jerks in the legs and feet. Since electrophysiological studies were not done, subclinical neuropathy was not excluded. In another group of 27 haemodialysis patients (15 male, age 51 [7] years, duration of dialysis 41 [3] months), 11 of whom were among the 55 in the first study, we investigated the effect of epoetin alfa (’Exprex’, Janssen-Cilag, initially 40 units/kg intravenously three times per week, titrated to maintain haemoglobin concentration between 90 and 100 g/1). Before and after 6 and 12 months of epoetin alfa patients were asked to grade the severity of restless legs from 1 (not present) to 7 (very severe). Iron was given if ferritin was less than 100 gg/1. 17 patients had restless legs before treatment with epoetin alfa (score 4-1 [0’5]); the symptom was less severe after 6 months (score 2-3 [0.4],p < 0-01) and 12 months (19 [0.3], p < 0-01) of treatment. Haemoglobin concentration was 66 (3) g/l before at 6 months and 96 (2) treatment, and rose to 99 (2) (p
Possible relation between restless legs and anaemia in renal dialysis patients SIR,--One of the
Fig 1-Typical "P-MR spectra obtained at rest from calf muscle of MH susceptible (L) and non-susceptible (R) subject. PME=phosphomonoesters; Pi=inorganic phosphate; PDE= phosphodiesters; truncated peaks are PCr=phosphocreatine, ATP=adenosine triphosphate; ppm=parts per million.
most troublesome and difficult to treat of is uraemia restless legs. The pathophysiology is not symptoms known, but has been related to peripheral neuropathy in uraemic patients1 and to anaemia and iron deficiency in others.2 We have evaluated patients on chronic haemodialysis and peritoneal dialysis for clinical and biochemical associations of restless legs and for the effect of correction of anaemia with epoetin alfa. 55 patients (22 male, mean age 53 [SEM 2] years, mean duration of dialysis 37 [6] months) receiving either haemodialysis (n 34) or continuous ambulatory peritoneal dialysis (21) were assessed. Restless legs was graded according to severity (4 = severe, intolerable affecting sleep; 3 annoying, every day; 2 moderate, more than once a week; 1 = mild, not more than once per week; 0 = none). 22 patients (40 %) had restless legs. It was more common in women than in men (p 0-03), and was related to time on dialysis (long vs short time, p < 0-01). Patients with restless legs had a lower haemoglobin than those who did not (82 [4] vs 95 [4] g/l, p 0-03). Age, type of dialysis, and serum biochemistry (including electrolytes, urea, creatinine, calcium, phosphorus and magnesium) did not differ between those who had restless legs and those who did not. There was no relation between the presence or severity of the restless legs syndrome and clinical evidence of peripheral neuropathy, or its severity, as assessed clinically by grading of any vibration sense and tendon jerks in the legs and feet. Since electrophysiological studies were not done, subclinical neuropathy was not excluded. In another group of 27 haemodialysis patients (15 male, age 51 [7] years, duration of dialysis 41 [3] months), 11 of whom were among the 55 in the first study, we investigated the effect of epoetin alfa (’Exprex’, Janssen-Cilag, initially 40 units/kg intravenously three times per week, titrated to maintain haemoglobin concentration between 90 and 100 g/1). Before and after 6 and 12 months of epoetin alfa patients were asked to grade the severity of restless legs from 1 (not present) to 7 (very severe). Iron was given if ferritin was less than 100 gg/1. 17 patients had restless legs before treatment with epoetin alfa (score 4-1 [0’5]); the symptom was less severe after 6 months (score 2-3 [0.4],p < 0-01) and 12 months (19 [0.3], p < 0-01) of treatment. Haemoglobin concentration was 66 (3) g/l before at 6 months and 96 (2) treatment, and rose to 99 (2) (p
