2013 Volume 40 Issue 5 Pages 504-511
Chronic kidney disease (CKD) has attracted attention as a condition that can progress to end-stage kidney disease, one that can serve as a risk factor for the development of cardiovascular diseases or even death. We conducted a cross-sectional study among recipients of multiphasic health testing and services to determine the levels of awareness about CKD, the self-reported salt intake levels, the urinary salt excretion levels, and a suitable method to evaluate the estimated glomerular filtration rate (eGFR) as a reliable screening method for CKD.
One-hundred seven men and women (age: 49.6±11.4) who received multiphasic health testing and services between October 2010 and August 2011 who were free from diseases requiring treatment or chronic diseases under follow-up observation at the time of enrollment were enrolled as the subjects.
In addition to the ordinary health testing items, a self-reporting questionnaire for CKD was prepared for this study, and the questionnaires were recovered on the day of the health testing and service. Serum cystatin C, spot urinary sodium concentration, spot urinary albumin concentration and spot urinary creatinine concentration were measured in addition to the routine testing, and the spot urine sodium chloride (NaCl) excretion and eGFR were calculated by estimation equations
Of the surveyed subjects, 56.1% were not aware about CKD. The urinary NaCl excretion (7.8±2.0g/day) was in the range of 3.3 to 12.0g/day. There was no correlation between the urinary NaCl excretion and the self-reported levels of salt intake; the salt intake was high in those who reported that their dietary intake was high (p=0.02). A positive correlation was observed (r=0.576, p<0.0001) between the eGFR (eGFRcreat) values calculated using creatinine and those calculated using cystatin C (eGFRcys). The eGFR was less than 60mL/min/1.73m2 in 5 cases and 1 case, respectively, when the eGFRcreat and eGFRcys were used for the estimation. There was no relation between the urinary albumin excretion and the eGFR.
As the level of awareness about CKD among recipients of multiphasic health testing and services was low, an improvement of the awareness through health testing and services is required. The discrepancy between the self-reported level of salt intake and the urinary NaCl excretion suggested that the validity of evaluation of the salt intake by diagnostic interview examination was low. Use of eGFRcreat for CKD screening may be associated with a reduced risk of overlooking CKD.
