{'fraction_non_alphanumeric': 0.052251486830926085, 'fraction_numerical': 0.045454545454545456, 'mean_word_length': 4.515222482435597, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 1, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Hypercalcemia and Insomnia in Hemodialysis Patients

Accessible online at: www.karger.com/journals/nef Dear Sir, We read with great interest the paper by Argiles et al. [1] about a hemodialysis (HD) patient who complained of sweating, pruritus and insomnia, and was irritable and restless. Moderate hypercalcemia (total Ca 2.9 mmol/l) was found and suspected as the cause of these symptoms. He had unintentionally received a dialysate with 1.75 mmol/l Ca and after lowering the Ca concentration in the dialysate (1.75k1.25 mmol/l) clinical manifestations rapidly resolved. In a previous paper about 14 symptoms in HD patients, we reported that insomnia, defined as ‘waking at night and failing to return to sleep’ or ‘not sleeping at all’, had a relation with the midweek predialysis total serum calcium (sCa) [2]. In fact, sCa in patients with absent vs occasional vs constant insomnia were 9.8 (9.6–10.3) vs. 9.9 (9.2–10.3) vs. 10.3 B 0.5, respectively, with a significant statistical difference (p = 0.041: 0–1 vs. 2). This association does not appear to have been reported before. Moreover, of the 15 patients reporting persistent insomnia, 12 (80%) had a predialysis sCa of 110 mg/dl and we defined them as ‘hypercalcemic’ because of a probable mild hypercalcemia during the interdialysis period with regard to the Ca concentration in the dialysate (1.75 for bicarbonate HD and 2.00 mmol/l for acetate-free biofiltration). One year later (June 1998), we changed the Ca concentration in the dialysate (1.75– 2.00k1.25 mmol/l) and after 5 months (November 1998) we reevaluated all our patients with regard to insomnia as well as other uremic symptoms using the same procedure as in the previous study [2]. Results on the comparison between the two evaluations are summarized in table 1. sCa data are expressed as mean B SD or median value (interquartile range) if the distribution was not Gaussian. Insomnia data were available for 73 of 76 and 68 of 70 patients in June 1997 and November 1998, respectively, and the sCa dosage is given for all patients. Nonparametric Mann-Whitney twotailed U test (sCa), Fisher exact test (% of patients with sCa 110 mg/dl) and ̄2 test (absent, occasional, constant insomnia) were used to compare the June 1987 and November 1998 data. The null hypothesis was rejected for all tests with two-tailed · values of !0.05.