Hubungan antara Kesadahan Air Minum, Kadar Kalsium dan Sedimen Kalsium Oksalat Urin pada Anak Usia Sekolah Dasar

Background: Water hardness containing calcium mineral (Ca2+) is supposed to increase absorption in intestinal lumen and calcium excretion (hyper-calciuria) of urine. Alkalic conditioned urine can cause changes of saturation concentration to become calcium supersaturation leading to the crystalization of calcium oxalate.Objective: To identify the relationship between drinking water hardness, drinking and eating habit to calcium level and urine calcium oxalate sediment.Method: The study was observational with cross sectional design. Examination analysis of drinking water hardness (mg/l), level of urine calcium (mg/dl) and calcium oxalate sediment of first/morning urine samples of 128 elementary school students (6-12 years old) was carried out using one-stage cluster random sampling technique at Sidowangi Subdistrict of Kajoran, District of Magelang, Central Java. Data of drinking and eating habit for bestial protein, vegetable protein, calcium and phospor, uric acid, oxalic acid and citric acid of the subject of the study were obtained from interview using questionnaires and food frequency forms. Data analysis used Stata version 8.0 program for windows at significance level. p