Table 1.

Baseline characteristics of patients investigated according to treatment time (either all hypertension medications upon awakening or ≥1 medication at bedtime)

VariableaAwakeningBedtimeP between groups
Demographic characteristics
    Patients (n)332329
    eGFR <60 ml/min per 1.73 m2 and albuminuria (n)4345
    eGFR ml/min per 1.73 m2 <60 without albuminuria (n)120115
    eGFR ml/min per 1.73 m2 >60 and albuminuria (n)169169
    Proteinuriab13.6 (45)15.5 (51)0.477
    Gender (men)b62.9 (209)56.8 (187)0.109
    Diabetesb32.8 (109)33.7 (111)0.805
    Obstructive sleep apneab14.7 (49)12.5 (41)0.389
    Metabolic syndrome72.3 (240)70.2 (231)0.218
    Cigarette smokingb16.0 (53)14.3 (47)0.547
    Obesityb53.6 (178)50.8 (167)0.463
    Previous CVD eventsb6.9 (23)7.3 (24)0.854
    Duration of known hypertension (year)6.8 ± 8.37.1 ± 8.10.452
    Anthropometric variables and office BP
    Age (year)60.3 ± 13.658.5 ± 13.20.619
    Height (cm)161.6 ± 9.0161.8 ± 9.70.736
    Weight (kg)81.1 ± 16.480.4 ± 16.30.589
    BMI30.9 ± 5.230.6 ± 5.10.398
    Waist (cm)100.6 ± 13.299.2 ± 11.90.162
    Clinic SBP (mmHg)c157.8 ± 23.4158.5 ± 21.40.658
    Clinic DBP (mmHg)c87.0 ± 13.588.8 ± 12.70.298
Clinical laboratory test values
    Glucose (mg/dl)120.3 ± 44.3120.0 ± 45.70.938
    Creatinine (mg/dl)1.19 ± 0.401.15 ± 0.330.146
    Uric acid (mg/dl)6.5 ± 2.06.4 ± 1.70.173
    Total cholesterol (mg/dl)210.4 ± 44.5212.0 ± 41.80.627
    Triglycerides (mg/dl)132.6 ± 69.5126.1 ± 75.50.259
    HDL-cholesterol (mg/dl)44.8 ± 14.345.6 ± 14.60.475
    LDL-cholesterol (mg/dl)139.8 ± 36.0140.6 ± 34.90.757
    Hemoglobin (g/dl)14.2 ± 1.914.1 ± 1.50.519
    Erythrocyte sedimentation rate (mm)18.6 ± 18.217.7 ± 15.70.453
    eGFR (ml/min per 1.73 m2)65.8 ± 22.266.6 ± 21.00.784
    Albumin, mg/24-hour urined64.8 (32.1 to 187.8)59.2 (31.8 to 210.1)0.285
Ambulatory BP
    Awake SBP mean (mmHg)137.7 ± 18.4137.4 ± 16.20.846
    Asleep SBP mean (mmHg)129.0 ± 20.8128.7 ± 18.50.871
    48-hour SBP mean (mmHg)134.9 ± 18.5134.6 ± 16.00.836
    Sleep-time relative SBP decline (%)6.2 ± 8.56.2 ± 9.10.950
    Awake DBP mean (mmHg)80.3 ± 13.082.5 ± 12.60.558
    Asleep DBP mean (mmHg)71.2 ± 12.373.0 ± 11.30.128
    48-hour DBP mean (mmHg)77.4 ± 12.479.4 ± 11.70.342
    Sleep-time relative DBP decline (%)11.1 ± 9.511.1 ± 8.90.942
    Nondipper (%)67.865.10.458
  • a Values are shown as mean ± SD. eGFR, estimated GFR (ml/min per 1.73 m2) using the MDRD-4 equation.15 Albuminuria, urinary albumin excretion ≥30 mg/24-hour urine. Proteinuria, urinary albumin excretion ≥300 mg/24-hour urine. Metabolic syndrome: National Cholesterol Education Program Adult Treatment Panel III (ATP-III) revised definition.16 Obesity, body mass index (BMI) ≥30, calculated as weight in kilograms divided by height in meters squared (kg/m2). The sleep-time relative BP decline, an index of BP dipping, is defined as the percent decline in mean BP during night-time sleep relative to the mean BP during daytime activity and was calculated as follows: [(awake BP mean − asleep BP mean)/awake BP mean] × 100. Nondipper, patients with sleep-time relative SBP decline <10%, using data sampled by ABPM for 48 consecutive hours.

  • b Values are percentages with number of subjects in parentheses.

  • c Values correspond to the average of six conventional BP measurements obtained for each subject at the clinic before starting 48-hour ABPM.

  • d Values are medians with interquartile range in parentheses.