Ambulatory blood pressure monitoring for risk stratification in obese and non-obese subjects from 10 populations.

Overweight clusters with high blood pressure (BP), but the independent contribution of both risk factors remains insufficiently documented. In a prospective population study involving 8467 participants (mean age 54.6 years; 47.0% women) randomly recruited from 10 populations, we studied the contribution of body mass index (BMI) to risk over and beyond BP, taking advantage of the superiority of ambulatory over conventional BP. Over 10.6 years (median), 1271 participants (15.0%) died and 1092 (12.9%), 637 (7.5%) and 443 (5.2%) experienced a fatal or nonfatal cardiovascular, cardiac or cerebrovascular event. Adjusted for sex and age, low BMI (<20.7 kg m(-2)) predicted death (hazard ratio (HR) vs average risk, 1.52; P<0.0001) and high BMI (> or = 30.9 kg m(-2)) predicted the cardiovascular end point (HR, 1.27; P=0.006). With adjustments including 24-h systolic BP, these HRs were 1.50 (P<0.001) and 0.98 (P=0.91), respectively. Across quartiles of the BMI distribution, 24-h and nighttime systolic BP predicted every end point (1.13 < or = standardized HR < or = 1.67; 0.046 < or = P<0.0001). The interaction between systolic BP and BMI was nonsignificant (P > or = .22). Excluding smokers removed the contribution of BMI categories to the prediction of mortality. In conclusion, BMI only adds to BP in risk stratification for mortality but not for cardiovascular outcomes. Smoking probably explains the association between increased mortality and low BMI.

Comentario del trabajo: efectos de los diferentes sistemas de producción sobre la composición y calidad de las carnes de los Dres. Andrés Gil y Stella Huertas / Commentary: production system outcomes on meat composition and quality. Dres. Andrés Gil and Stella Huertas

El presente estudio, coordinado por los doctores veterinarios Andrés Gil y Stella Huertas, fue realizado por un grupo de trabajo multiinstitucional integrado por delegados de la Facultad de Veterinaria (Universidad de la República), Facultad de Veterinaria (Universidad de Minnesota, Estados Unidos), Instituto Nacional de Investigación Agropecuaria, Instituto NAcional de Carnes, Instituto Plan Agropecuario, Dirección de Laboratorios Veterinarios (Ministerio de Ganadería), Asociación Rural, Sociedad de Criadores de Hereford y de la Organización Partners Uruguay-Minnesota. La idea de realizarlo surgió de un grupo de veterinarios, entre ellos el Dr. Stanley Diesch, profesor en la Facultad de Veterinaria de Minnesota, que postularon que la composición de la carne bovina podría explicar por qué los uruguayos, a pesar de consumir más carne vacuna, tuvieran índices de enfermedades cardiovasculares inferiores a los estadounidenses. La razón de esa diferencia -postularon- podría estar en la forma de alimentación de los bovinos en ambos países, pues mientras en Uruguay se alimentan en pasturas, en Estados Unidos lo hacen a base de granos, mediante el sistema llamado feedlot. Es así que se planteó estudiar la composición y calidad de las carnes de Uruguay, y establecer una relación entre estas características y la forma de alimentación de los animales. Para ello se realizaron 2 investigaciones en paralelo: un estudio randomizado evaluando dos sistemas de alimentación bovina y un estudio observacional al nivel dee frigoríficos y puntos de venta.

Ambulatory blood pressure: normality and comparison with other measurements. Hypertension Working Group.

Previous studies have reported results on 24-hour ambulatory blood pressure (ABP) in Europe and Japan, but no data exists from South America. In this study, we conducted a population survey to identify reference values and to compare ambulatory blood pressure with clinic, home, and self-measured values. A random sample of 2650 adults was selected among 190 000 people covered by our prepaid healthcare institution. Clinic (physician and nurse) and home (nurse) blood pressure measurements were performed 3 times each, with semiautomatic electronic equipment. Self-measurements were performed by the subjects manually activating the ambulatory device. We analyzed 1573 individuals who were not receiving antihypertensive therapy from 1921 participants. Self-measurement was available in a subgroup of 577 participants younger than the whole sample. Normal ambulatory blood pressure limits were estimated as those that best correlated with 140/90 mm Hg at clinic. Estimated values were 125/80 mm Hg for 24-hour ambulatory (range: 122 to 128 and 77 to 83 mm Hg) and 129/84 mm Hg for daytime ambulatory (range: 127 to 132 and 81 to 86) blood pressure, depending on gender and age. Ambulatory and clinic blood pressures increased with age. The age-dependent increase in ABP was similar in women and men. Average blood pressure at clinic was 124/79 mm Hg by physician and 123/78 mm Hg by nurse. Nurse measurement at home was 125/78 mm Hg, daytime ambulatory was 121/77 mm Hg, and 24-hour ambulatory was 118/74 mm Hg. The values of the subgroup with self-measurement were physician 119/77 mm Hg; nurse at clinic 118/77 mm Hg; nurse at home 121/78 mm Hg; self-measured 115/72 mm Hg; daytime ambulatory 119/77 mm Hg; and 24-hour ambulatory 115/73 mm Hg. This study shows that a 24-hour ABP average value of 125/80 mm Hg and a daytime ABP average value of 129/84 mm Hg are suitable upper limits for normality. Higher limits would yield an artificially higher prevalence of white coat hypertension. Most subjects showed higher blood pressure levels when measurements were performed by healthcare personnel at a clinic or at home than when self-measured at home.