Table 1.
Baseline characteristics of study participants
| Serum phosphorus level | ||||||
|---|---|---|---|---|---|---|
| Variables | Total (n = 20,686) |
1st quartile (n = 5660) |
2nd quartile (n = 5717) |
3rd quartile (n = 4487) |
4th quartile (n = 4822) |
P |
| Age (years) | 58.9 ± 17.0 | 61.4 ± 16.1 | 59.5 ± 16.7‡ | 57.6 ± 17.1‡ | 56.5 ± 18.1‡ | < 0.001 |
| Male sex (%) | 52.5 | 57.4 | 55.2 | 50.6‡ | 46.1‡ | < 0.001 |
| Body mass index (kg/m2) | 23.7 ± 3.7 | 23.6 ± 3.7 | 23.8 ± 3.6 | 23.7 ± 3.6* | 23.9 ± 3.9† | 0.002 |
| Comorbidities (%) | ||||||
| Hypertension | 19.0 | 17.9 | 18.6 | 18.4 | 21.5‡ | < 0.001 |
| Diabetes mellitus | 21.9 | 22.5 | 20.8 | 19.7† | 24.5 | < 0.001 |
| History of cardiovascular disease | 6.1 | 5.8 | 6.3 | 6.7 | 5.8 | 0.164 |
| Chronic kidney disease | 8.0 | 8.7 | 7.0* | 7.0* | 9.4 | < 0.001 |
| Medications (%) | ||||||
| ACEi | 1.4 | 1.1 | 1.3 | 1.6 | 1.6 | 0.180 |
| ARB | 6.4 | 5.9 | 6.2 | 6.4 | 7.2* | 0.040 |
| Beta blocker | 5.9 | 4.5 | 6.1† | 6.2† | 7.1‡ | < 0.001 |
| Calcium channel blocker | 7.1 | 6.7 | 6.9 | 7.2 | 7.7* | 0.193 |
| Diuretics | 5.3 | 5.2 | 4.9 | 4.6 | 6.4† | 0.001 |
| Laboratory findings | ||||||
| Hemoglobin (g/dL) | 12.6 ± 2.1 | 12.3 ± 2.2 | 12.8 ± 2.0‡ | 12.9 ± 2.0‡ | 12.7 ± 2.2‡ | < 0.001 |
| Albumin (g/dL) | 3.9 ± 0.6 | 3.7 ± 0.6 | 4.0 ± 0.6‡ | 4.0 ± 0.5‡ | 4.0 ± 0.6‡ | < 0.001 |
| Total cholesterol (mg/dL) | 170.1 ± 47.5 | 157.3 ± 46.4 | 171.2 ± 43.8‡ | 177.5 ± 47.3‡ | 177.2 ± 50.0‡ | < 0.001 |
| Calcium (mg/dL) | 8.6 ± 0.7 | 8.3 ± 0.7 | 8.7 ± 0.6‡ | 8.8 ± 0.5‡ | 8.8 ± 0.7‡ | < 0.001 |
| Phosphorus (mg/dL) | 3.38 ± 0.81 | 2.46 ± 0.41‡ | 3.21 ± 0.14‡ | 3.64 ± 0.11‡ | 4.38 ± 0.73‡ | < 0.001 |
| Creatinine (mg/dL) | 0.82 ± 0.72 | 0.77 ± 0.42 | 0.76 ± 0.57 | 0.77 ± 0.44 | 1.00 ± 1.28‡ | < 0.001 |
| eGFR (mL/min/1.73 m2) | 86.0 ± 35.5 | 88.9 ± 37.4 | 85.6 ± 36.8‡ | 84.6 ± 30.2‡ | 84.4 ± 36.2‡ | < 0.001 |
Comparisons were evaluated using the Kruskal wallis test for categorical variables and analysis of variance for continuous variables (post-hoc analysis of least significant difference between the two groups). The first quartile group served as a reference for the comparison between the two groups
ACEi angiotensin-converting enzyme inhibitor, ARB angiotensin II receptor blocker, eGFR estimated glomerular filtration rate
*P < 0.05; †P < 0.01; ‡P < 0.001, compared with the 1st quartile