Fig 1.
Flow diagram of healthy subjects.
Persons without any diseases were defined as healthy subjects. There were 72,521 subjects in the cross-sectional study. In the longitudinal study, eGFR decline rate was evaluated in 45,586 subjects and relationships between eGFR decline rate and 15 baseline factors were evaluated in 43,438 subjects. §After the second medical checkup, there was no subject who received renal transplantation. All data corresponding to the particular medical checkup were excluded for subjects diagnosed with hyperthyroidism or hypothyroidism based on blood tests or those without urinalysis or blood pressure measurements in a second or later medical checkup, and *the numbers of subjects for whom data were not included in each checkup were 567(2nd), 389(3rd), 277(4th), 216(5th), 153(6th), 99(7th), 64(8th), 37(9th), 5(10th), and 1(12th).
Table 1.
List of excluded diseases.
Table 2.
Characteristics of healthy subjects in the cross-sectional and longitudinal studies.
Fig 2.
Reference values for eGFR in healthy men and women in the cross-sectional study.
Values for eGFR decreased with older age in both genders. eGFR was calculated using the 3-variable Japanese equation.
Table 3.
Slope (ml/min/1.73m2/year) of eGFR decline in healthy men.
Table 4.
Slope (ml/min/1.73m2/year) of eGFR decline in healthy women.
Fig 3.
Graphs of the rate of eGFR decline in healthy men and women by renal stage and age group.
The mean slope for each stratified component by gender, age and renal stage in Tables 3 and 4 is plotted on the y-axis, and age group and renal stage are plotted on the x-axis. When the slope was stratified by renal stage and gender, all lines ran almost parallel with the x-axis showing age group (left side).When the slope was stratified by age group and gender, all lines almost overlapped (right side). There was little difference in slope within the same renal stage regardless of age, whereas the slope changed depending on the renal stage. The slope was steeper when baseline eGFR was higher (i.e. better renal function) and shallower when baseline eGFR was lower (i.e. renal stage changed from G1 to G3b).
Fig 4.
Graph of the slope of eGFR decline (simulated change of eGFR) in healthy men and women.
The slope of eGFR decline is depicted as the inclination of each line. The trajectory of renal function based on this slope was predicted with a simulation method. The shape of the graph was gently convex downward, which matches the tendency for the slope of eGFR decline to be steeper for higher baseline eGFR and shallower for lower baseline eGFR.
Table 5.
Rate of eGFR decline (Slope and %Slope) evaluated by linear least-squares regression analysis using 15 factors at baseline.