Table 1.
Baseline characteristics of the study population
| Parameter | Essential hypertension (n = 100) | Primary aldosteronism (n = 54) | P value |
|---|---|---|---|
| Clinical characteristics | |||
| Age (yr) | 52 ± 10 | 53 ± 12 | NS |
| Females/males | 31/69 | 16/38 | NS |
| Body mass index (kg/m2) | 28.2 ± 3.2 | 28.6 ± 3.8 | NS |
| Heart rate (beats/min) | 70 ± 3 | 70 ± 4 | NS |
| Systolic blood pressure (mm Hg)a | 165 ± 17 | 167 ± 16 | NS |
| Diastolic blood pressure (mm Hg)a | 102 ± 9 | 103 ± 9 | NS |
| Estimated duration of hypertension (yr) | 10 ± 7 | 10 ± 7 | NS |
| Current smoking, no. (%) | 24 (24) | 15 (28) | NS |
| Alcohol intake (g/d) | 32 ± 11 | 34 ± 9 | NS |
| Laboratory variables | |||
| Plasma glucose (mmol/liter) | 4.8 ± 1.0 | 4.9 ± 0.9 | NS |
| Total cholesterol (mmol/liter) | 5.28 ± 1.05 | 5.13 ± 1.09 | NS |
| HDL cholesterol (mmol/liter) | 1.29 ± 0.32 | 1.26 ± 0.41 | NS |
| Triglycerides (mmol/liter) | 1.36 ± 0.81 | 1.23 ± 0.70 | NS |
| Plasma sodium (mmol/liter) | 140 ± 3 | 141 ± 4 | NS |
| Plasma potassium (mmol/liter) | 4.2 ± 0.3 | 3.2 ± 0.4b | <0.001 |
| Urinary sodium excretion (mmol/24 h) | 107 ± 45 | 101 ± 63 | NS |
| Urinary potassium excretion (mmol/24 h) | 46 ± 21 | 52 ± 19 | NS |
| Plasma aldosterone (pg/ml) | 149 ± 87 | 246 ± 191 | <0.001 |
| Plasma active renin (pg/ml) | 9.1 ± 9.7 | 4.8 ± 6.4 | <0.001 |
| Aldosterone to active renin ratio | 16.4 ± 2.0 | 51.3 ± 3.5 | <0.001 |
| Serum creatinine (μmol/liter) | 100 ± 38 | 91 ± 20 | NS |
| Creatinine clearance (ml/min/1.73 m2) | 87 ± 37 | 105 ± 31 | 0.003 |
| Urinary albumin excretion (mg/24 h)c | 15 [6–26] | 22 [9–38] | 0.016 |
| Urinary albumin/creatinine ratioc | 0.045 [0.019–0.087] | 0.046 [0.021–0.086] | NS |
Values are means ± sd unless otherwise indicated. P values are calculated by the Student’s t test. Normal reference values for plasma measurements: glucose, 4.2–6.4 mmol/liter; total cholesterol, <5.17 mmol/liter; HDL-cholesterol, 1.03–2.19 mmol/liter; triglyceride, 0.57–1.90 mmol/liter; sodium, 132–148 mmol/liter; potassium, 3.5–5.0 mmol/liter, aldosterone, 30–220 pg/ml; active renin, 2.5–18 pg/ml. HDL, High-density lipoprotein; NS, not significant.
a
Blood pressure was measured after appropriate washout of antihypertensive drugs.
b
Values are those that were measured before correction with oral supplementation.
c
Median [interquartile range].