RESUMEN
Hypertension remains the most common modifiable cardiovascular risk factor, yet hypertension control rates remain dismal. Home blood pressure (BP) monitoring has the potential to improve hypertension control. The purpose of this review was to quantify both the magnitude and mechanisms of benefit of home BP monitoring on BP reduction. Using a structured review, studies were selected if they reported either changes in BP or percentage of participants achieving a pre-established BP goal between randomized groups using home-based and office-based BP measurements. A random-effects model was used to estimate the magnitude of benefit and relative risk. The search yielded 37 randomized controlled trials with 9446 participants that contributed data for this meta-analysis. Compared with clinic-based measurements (control group), systolic BP improved with home-based BP monitoring (-2.63 mm Hg; 95% CI, -4.24, -1.02); diastolic BP also showed improvement (-1.68 mm Hg; 95% CI, -2.58, -0.79). Reductions in home BP monitoring-based therapy were greater when telemonitoring was used. Home BP monitoring led to more frequent antihypertensive medication reductions (relative risk, 2.02 [95% CI, 1.32 to 3.11]) and was associated with less therapeutic inertia defined as unchanged medication despite elevated BP (relative risk for unchanged medication, 0.82 [95% CI, 0.68 to 0.99]). Compared with clinic BP monitoring alone, home BP monitoring has the potential to overcome therapeutic inertia and lead to a small but significant reduction in systolic and diastolic BP. Hypertension control with home BP monitoring can be enhanced further when accompanied by plans to monitor and treat elevated BP such as through telemonitoring.
Asunto(s)
Antihipertensivos/uso terapéutico , Monitoreo Ambulatorio de la Presión Arterial , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Presión Sanguínea/efectos de los fármacos , Femenino , Humanos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Riesgo , Resultado del TratamientoRESUMEN
Although obesity is associated with poor outcomes, among patients with chronic kidney disease (CKD), obesity is related to improved survival. These results may be related to poor diagnostic performance of body mass index (BMI) in assessing body fat content. Accordingly, among 77 patients with CKD and 20 controls, body fat percentage was estimated by air displacement plethysmography (ADP), skinfold thickness, and body impedance analysis. Defined by BMI ≥30 kg/m(2), the prevalence of obesity was 20% in controls and 65% in patients with CKD. Defined by ADP, the prevalence increased to 60% among controls and to 90% among patients with CKD. Although sensitivity and positive predictive value of BMI to diagnose obesity were 100%, specificity was 72%, but the negative predictive value was only 30%. BMI correctly classified adiposity in 75%. Regardless of the presence or absence of CKD, subclinical obesity (defined as BMI <30 kg/m(2) but excess body fat by ADP) was often missed in people with low lean body mass. The adjusted odds ratio for subclinical obesity per 1 kg of reduced lean body mass by ADP was 1.14 (95% CI: 1.06 to 1.23; P<0.001). Skinfold thickness measurements correctly classified 94% of CKD patients, but bioelectrical impedance analyzer-assessed body fat estimation did so in only 65%. Air displacement plethysmography-, skinfold thickness-, and bioelectrical impedance analyzer-assessed body fat all provided reproducible estimates of adiposity. Skinfold thickness measurements may be a better test to classify obesity among those with CKD. Given the low negative predictive value of BMI for obesity, our study may provide an explanation of the "obesity paradox."
Asunto(s)
Composición Corporal , Índice de Masa Corporal , Fallo Renal Crónico/complicaciones , Obesidad/complicaciones , Obesidad/diagnóstico , Anciano , Impedancia Eléctrica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pletismografía , Valor Predictivo de las Pruebas , Análisis de Regresión , Sensibilidad y Especificidad , Grosor de los Pliegues Cutáneos , Relación Cintura-CaderaRESUMEN
Patients with chronic kidney disease have less than expected decline in blood pressure during sleep (nondipping) and commonly experience the vexing symptom of nocturia. To better understand the relationship among nocturia, nighttime physical activity, and nondipping, we studied 98 patients with chronic kidney disease on 2 occasions, 1 month apart, with 24-hour ambulatory blood pressure monitoring and simultaneous activity monitoring with wrist actigraphy. Patients with nocturia had greater actigraphically recorded nighttime physical activity compared to those with no nocturia. The drop in activity from wake to sleep was reduced to a similar extent whether the patients had nocturia once or twice, but patients who had nocturia >/=3 times had the least reduction from wake to sleep activity (P<0.001 versus those with less degrees of nocturia). Those with nocturia had a lesser drop in systolic ambulatory blood pressure during sleep compared with those without nocturia. The average fall in sleep systolic blood pressure was 9.8 mm Hg (95% CI: 8.0 to 11.6 mm Hg) in those without nocturia compared with 3.4 mm Hg (95% CI: 2.7 to 4.1 mm Hg) in those with any severity of nocturia (P<0.001 for difference). Nondipping in patients with nocturia was mediated by nighttime physical activity. These differences were independent of estimated glomerular filtration rate, albuminuria, or use of diuretics. Thus, nocturia, which may reflect impaired renal tubular function, is associated with nondipping in patients with chronic kidney disease and appears to be mediated by increased nocturnal activity. Whether nocturia itself or the resulting nondipping associated with nocturia is of prognostic importance for cardiorenal events in patients with chronic kidney disease should be tested in future studies.
Asunto(s)
Presión Sanguínea/fisiología , Fallo Renal Crónico/fisiopatología , Nocturia/fisiopatología , Anciano , Anciano de 80 o más Años , Albuminuria/fisiopatología , Monitoreo Ambulatorio de la Presión Arterial/métodos , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía/métodosRESUMEN
BACKGROUND AND OBJECTIVES: Measurement of GFR is important for the management of chronic kidney disease (CKD). Although bolus administration of radiocontrast agents is commonly used to measure GFR, the optimal duration of sampling to assess their plasma clearance is unknown. The purpose of this study was to evaluate whether the duration of plasma sampling influences precision and estimation of GFR. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: GFR was measured by sampling plasma 12 times over 5 h in 56 patients with CKD (mean age 64 yr, 98% men, 79% Caucasian, 34% diabetics, estimated GFR 31.8 +/- 14.2 ml/min/1.73 m(2)). In a subset of 12 patients we measured GFR by sampling plasma 17 times over 10 h. RESULTS: Short sampling intervals considerably overestimated GFR measured using total plasma iothalamate clearance, especially in larger patients. In the higher estimated GFR group (>30 ml/min/1.73 m(2)), the 5-h GFR was 17% higher and 2-h GFR 54% higher compared with the 10-h GFR, which averaged 40.3 ml/min/1.73 m(2). In the lower estimated GFR group (<30 ml/min/1.73 m(2)), the 5-h GFR was 36% higher and 2-h GFR 126% higher compared with the 10-h GFR, which averaged 22.2 ml/min/1.73 m(2). Short sampling duration also reduced the precision of the estimated GFR from 1.67% for 10-h GFR, to 3.48% for 5-h GFR, and to 7.07% for 2-h GFR. CONCLUSIONS: GFR measured over a longer duration with multiple plasma samples spanning the distribution and elimination phases may improve precision and provide a better measure of renal function.
Asunto(s)
Medios de Contraste/farmacocinética , Tasa de Filtración Glomerular , Yotalamato de Meglumina/farmacocinética , Enfermedades Renales/diagnóstico , Riñón/fisiopatología , Anciano , Enfermedad Crónica , Medios de Contraste/administración & dosificación , Femenino , Humanos , Inyecciones Intravenosas , Yotalamato de Meglumina/administración & dosificación , Enfermedades Renales/fisiopatología , Masculino , Persona de Mediana Edad , Modelos Biológicos , Valor Predictivo de las Pruebas , Reproducibilidad de los ResultadosRESUMEN
Vitamin D receptor activation is associated with improved survival in patients with chronic kidney disease, but the mechanism of this benefit is unclear. To better understand the effects of vitamin D on endothelial function, blood pressure, albuminuria, and inflammation in patients with chronic kidney disease (2 patients stage 2, remaining stage 3), we conducted a pilot trial in 24 patients who were randomly allocated equally to 3 groups to receive 0, 1, or 2 microg of paricalcitol, a vitamin D analog, orally for 1 month. Placebo-corrected change in flow mediated dilatation with a 1-microg dose was 0.5% and 0.4% with a 2-microg dose (P>0.2). At 1 month, the treatment:baseline ratio of high sensitivity C-reactive protein was 1.5 (95% CI: 1.1 to 2.1; P=0.02) with placebo, 0.8 (95% CI: 0.3 to 1.9; P=0.62) with a 1-microg dose, and 0.5 (95% CI: 0.3 to 0.9; P=0. 03) with a 2-microg dose of paricalcitol. At 1 month, the treatment:baseline ratio of 24-hour albumin excretion rate was 1.35 (95% CI: 1.08 to 1.69; P=0.01) with placebo, 0.52 (95% CI: 0.40 to 0.69; P<0.001) with a 1-microg dose, and 0.54 (95% CI: 0.35 to 0.83; P=0. 01) with a 2-microg dose (P<0.001 for between group changes). No differences were observed in iothalamate clearance, 24-hour ambulatory blood pressure, or parathyroid hormone with treatment or on washout. Thus, paricalcitol-induced reduction in albuminuria and inflammation may be mediated independent of its effects on hemodynamics or parathyroid hormone suppression. Long-term randomized, controlled trials are required to confirm these benefits of vitamin D analogs.