Table 2.
Baseline characteristics according to low versus high 24UV
| Characteristic (n =650) | Low 24UV (n =325) | High 24UV (n =325) | P value* |
|---|---|---|---|
| Urine volume [L/24 h] |
1.0 (0.9 – 1.2) |
2.9 (2.7 – 3.5) |
--- |
| Age, years |
48 (30 – 63) |
47 (35 – 60) |
0.97 |
| Fluid intake [L/24 h] |
1.5 (1.0 – 1.5) |
2.0 (1.5 – 2.5) |
<.0001 |
| Urinary creatinine excretion [mg/kg/24 h] |
18.5 (15.1 – 22.7) |
19.3 (16.1 – 22.5) |
0.14 |
| Urinary sodium excretion [mmol/24 h] |
120 (94 – 165) |
171 (130 – 214) |
<.0001 |
| Serum creatinine [μmol/L] |
80 (70 – 91) |
75 (66 – 86) |
0.0002 |
| Creatinine clearance [ml/min] |
121 (100 – 142) |
109 (90 – 132) |
0.0044 |
| eGFR (CKD-EPI) [ml/min/1.73 m2] |
91 (75 – 107) |
93 (81 – 105) |
0.21 |
| Body mass index [kg/m2] |
24 (22 – 28) |
24 (22 – 27) |
0.72 |
| Hypertension |
82 (25%) |
72 (22%) |
0.04 |
| Oral anti-diabetic medication |
13 (4%) |
5 (2%) |
0.11 |
| History of nephrolithiasis |
32 (9.7%) |
27 (8.2%) |
0.79 |
|
Education |
|
|
0.01 |
| Primary level |
44 (14%) |
28 (8%) |
|
| Secondary level |
152 (47%) |
138 (42%) |
|
| Tertiary level |
110 (34%) |
147 (45%) |
|
| Other |
17 (5%) |
12 (4%) |
|
|
Smoking |
|
|
0.09 |
| Current Smokers |
64 (20%) |
49 (15%) |
|
| Past Smokers |
78 (24%) |
99 (30%) |
|
| Never Smokers |
178 (55%) |
176 (53%) |
|
|
Cups of coffee per day |
|
|
0.19 |
| 0 |
27 (8%) |
17 (5%) |
|
| 1-3 |
224 (69%) |
207 (63%) |
|
| ≥4 |
72 (22%) |
100 (31%) |
|
|
Alcohol consumption |
|
|
0.10 |
| Never |
53 (16%) |
39 (12%) |
|
| 1 – 2 times/week |
172 (53%) |
190 (58%) |
|
| > two days/week to daily |
71 (22%) |
79 (24%) |
|
| twice daily or more |
23 (7%) |
17 (5%) |
|
|
Vegetables and vegetables juices |
|
|
<.0001 |
| < once a day |
104 (32%) |
53 (16%) |
|
| 1 – 2 portions daily |
164 (50%) |
176 (54%) |
|
| ≥3 portions daily |
55 (17%) |
92 (28%) |
|
|
Fruits and fruit juices |
|
|
0.04 |
| < once a day |
110 (34%) |
68 (21%) |
|
| 1 – 2 portions daily |
157 (48% |
173 (53%) |
|
| >3 portions daily |
55 (17%) |
82 (25%) |
|
|
Meat or cold cut |
|
|
0.08 |
| once or < once weekly |
49 (15%) |
67 (21%) |
|
| 2 – 4 days weekly |
187 (58%) |
154 (47%) |
|
| >5 days weekly | 89 (27%) | 103 (32%) |
Urine volume was defined as high and low according to the highest and lowest quartile of 24UV. Values are median (interquartile ranges) or counts (percentages). Number of observations across categories may not sum to the given number because of missing data. eGFR estimated glomerular filtration rate, CKD-EPI Chronic Kidney Disease Epidemiology Collaboration. *Based on Kruskal-Wallis tests for continuous variables and chi-square tests for categorical variables.