Hidden chronic renal insufficiency and cardiovascular events in patients with hypertension in a primary care center

Figures & data

TABLE 1. General characteristics of the patients in the study

	Total (n = 756)
Age (years)	57.2 (9.6)
Males	316 (41.8%)
SBP (mmHg)	148.1 (17.5)
DBP (mmHg)	88.3 (9.9)
Total cholesterol (mg/dL)	242.6 (38.6)
HDL-C (mg/dL)	51.2 (14.6)
LDL-C (mg/dL)	164.1 (37.0)
Triglycerides (mg/dL)	119.0 (87.5–162.5)
Glycemia (mg/dL)	117.1 (40.4)
Creatinine (mg/dL)	0.97 (0.16)
BMI (kg/m^2)	29.1 (4.5)
Diabetes	185 (24.5%)
Smokers	161 (21.3%)
Antihypertensive drugs	346 (45.8%)
Lipid-lowering drugs	153 (20.2%)
GFR by the MDRD equation (mL/min/1.73 m^2)	73.8 (13.4)
GFR by the Cockcroft–Gault formula (mL/min/1.73 m^2)	80.3 (16.5)
Mean risk with the Framingham-REGICOR function	7.3% (5.2)
Mean risk with the original Framingham function	18.2% (12.5)
Coronary events^a	87 (11.5%)
Cerebral events^a	33 (4.4%)
Cardiovascular events^a	112 (14.8%)
Cardiovascular exitus^a	25 (3.3%)

Notes: Values are expressed as mean (standard deviation) or number of patients (percentage) in normal distributions, and as median (quartile 1–quartile 3) in non-normal distributions (triglycerides). SBP, systolic blood pressure; DBP, diastolic blood pressure; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; BMI, body mass index; GFR, glomerular filtration rate; MDRD, abbreviated formula from the Modification of Diet in Renal Disease study.

^aEvents during the 10 years of follow-up.

TABLE 2. General characteristics, cardiovascular events, and coronary risk in the patients with and without hidden chronic renal insufficiency criteria as estimated by the MDRD equation

	Patients without renal insufficiency (n = 656)	Patients with renal insufficiency (n = 100)	p-Value
Age (years)	55.8 (9.4)	65.2 (6.1)	<0.001
Males	304 (46.3%)	12 (12.0%)	<0.001
SBP (mmHg)	147.3 (17.2)	153.0 (18.3)	<0.01
DBP (mmHg)	88.4 (9.8)	87.8 (10.6)	0.455
Total cholesterol (mg/dL)	242.2 (39.1)	245.2 (34.9)	0.266
HDL-C (mg/dL)	50.9 (14.8)	52.7 (13.8)	0.155
LDL-C (mg/dL)	163.9 (37.3)	165.4 (35.3)	0.477
Triglycerides (mg/dL)	120.0 (87.0–167.0)	119.0 (92.0–153.0)	0.960
Glycemia (mg/dL)	116.0 (40.2)	124.3 (41.2)	0.195
Creatinine (mg/dL)	0.95 (0.15)	1.09 (0.10)	<0.001
BMI (kg/m^2)	28.9 (4.4)	30.1 (4.8)	0.059
Diabetes	153 (23.3%)	32 (32.0%)	0.060
Smokers	153 (23.3%)	8 (8.0%)	<0.001
Antihypertensive drugs	280 (42.7%)	66 (66.0%)	<0.001
Lipid-lowering drugs	125 (19.1%)	28 (28.0%)	0.089
Glomerular filtration rate by the MDRD equation (mL/min/1.73 m^2)	76.6 (12.2)	55.7 (3.4)	<0.001
Mean risk with the Framinghan-REGICOR function	7.2% (5.3)	7.7% (4.4)	<0.05
Mean risk with the original Framingham function	18.2% (12.7)	18.2% (10.7)	0.399
Coronary events	70 (10.7%)	17 (17.0%)	0.065
Cerebrovascular events	26 (4%)	7 (7.0%)	0.185
Cardiovascular events	90 (13.7%)	22 (22.0%)	<0.05
Cardiovascular exitus	20 (3.0%)	5 (5.0%)	0.361

Notes: Values are expressed as mean (standard deviation) or number of patients (percentage) in normal distributions, and as median (quartile 1–quartile 3) in non-normal distributions (triglycerides). MDRD, abbreviated formula from the Modification of Diet in Renal Disease study; SBP, systolic blood pressure; DBP, diastolic blood pressure; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; BMI, body mass index.

FIGURE 1. Percentage of cardiovascular events in the cohort during the 10-year follow-up, with glomerular filtration rate calculated using the MDRD equation. MDRD, abbreviated formula from the Modification of Diet in Renal Disease study; CRI, chronic renal insufficiency.

TABLE 3. General characteristics of the patients with and without cardiovascular events

	Patients without cardiovascular events (n = 644)	Patients with cardiovascular events (n = 112)	p-Value
Age (years)	56.3 (9.6)	61.2 (8.2)	<0.001
Males	254 (39.4%)	62 (55.4%)	<0.01
SBP (mmHg)	147.2 (17.2)	153.2 (18.3)	<0.01
DBP (mmHg)	88.0 (9.6)	90.4 (11.4)	<0.05
Total cholesterol (mg/dL)	243.3 (38.3)	238.9 (40.5)	0.266
HDL-C (mg/dL)	51.5 (15.0)	49.5 (12.2)	0.135
LDL-C (mg/dL)	164.8 (36.8)	160.4 (38.1)	0.258
Triglycerides (mg/dL)	118.0 (85.0–162.0)	125.0 (100.0–168.0)	0.319
Glycemia (mg/dL)	114.8 (39.3)	130.5 (44.0)	<0.001
Creatinine (mg/dL)	0.96 (0.15)	1.01 (0.16)	<0.01
BMI (kg/m^2)	29.0 (4.42)	29.9 (4.6)	0.068
Diabetes	139 (21.6%)	46 (41.1%)	<0.001
Smokers	126 (19.6%)	35 (31.3%)	<0.01
Antihypertensive drugs	279 (43.3%)	67 (59.8%)	<0.01
Lipid-lowering drugs	131 (20.3%)	22 (19.6%)	0.365
Mean risk with the Framingham-REGICOR function	6.8% (4.9)	9.8% (6.3)	<0.001
Mean risk with the original Framingham equation	17.2% (11.8)	24.5% (14.3)	<0.001
GFR estimated by the Cockcroft–Gault formula (mL/min/1.73 m^2)	81.1 (16.6)	75.2 (14.8)	<0.01
Patients with GFR<60 mL/min/1.73 m^2 by the Cockcroft–Gault formula	53 (9.0%)	14 (14.3%)	0.104
GFR estimated by the MDRD equation (mL/min/1.73 m^2)	74.1 (13.3)	71.9 (14.0)	0.109
Patients with GFR<60 mL/min/1.73 m^2 by the MDRD equation	78 (12.1%)	22 (19.6%)	<0.05

Notes: Values are expressed as mean (standard deviation) or number of patients (percentage) in normal distributions, and as median (quartile 1–quartile 3) in non-normal distributions (triglycerides). SBP, systolic blood pressure; DBP, diastolic blood pressure; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; BMI, body mass index; GFR, glomerular filtration rate; MDRD, abbreviated formula from the Modification of Diet in Renal Disease study.

TABLE 4. Predictors of cardiovascular events in the logistic regression multivariate analysis and estimation of renal function with the MDRD and Cockcroft-Gault formulas

	GFR estimated by MDRD equation			GFR estimated by Cockcroft–Gault formula
	Odds ratio	95% CI for the odds ratio	p-Value	Odds ratio	95% CI for the odds ratio	p-Value
Smokers	2.71	1.50–4.88	<0.01	2.75	1.53–4.95	<0.01
Diabetes	2.03	1.25–3.31	<0.01	2.04	1.25–3.33	<0.01
Age	1.08	1.05–1.11	<0.01	1.08	1.05–1.12	<0.001
DBP	1.03	1.01–1.06	<0.01	1.03	1.01–1.06	<0.01
Sex (male)	1.78	1.04–3.05	<0.05	1.67	1.00–2.81	0.051
BMI	1.03	0.97–1.08	0.340	1.03	0.97–1.09	0.306
GFR by the MDRD equation <60 mL/min/1.73 m^2	1.37	0.72–2.61	0.340
GFR by the Cockcroft–Gault formula <60 mL/min/1.73 m^2				1.053	0.50–2.23	0.893

Notes: GFR, glomerular filtration rate; MDRD, abbreviated formula from the Modification of Diet in Renal Disease study; 95% CI, 95% confidence interval; DBP, diastolic blood pressure; BMI, body mass index.

FIGURE 2. Kaplan–Meier survival curves for cardiovascular and coronary events in patients with and without hidden renal insufficiency with glomerular filtration rate calculated using the MDRD equation. MDRD, abbreviated formula from the Modification of Diet in Renal Disease study; GFR, glomerular filtration rate.