Riesgo de enfermedades cardiovasculares según categorías de presión arterial en una cohorte argentina

Background: Hypertension is a recognized strong risk factor for cardiovascular disease. However, no data was available in our country to quantify the relationship between blood pressure and cardiovascular event. Objective: to quantify the risk of cardiovascular events according to blood pressure categories. Methods: A prospective epidemiological study was conducted in 1526 inhabitants from Rauch City, (Buenos Aires, Argentina) between 1997 and 2012. Subjects were classified into one of these blood-pressure categories: 1-optimal, 2-normal, 3-high-normal, 4-grade 1 hypertension, 5-grade 2 hypertension and 6-grade 3 hypertension. The first CVD event, including unstable angina pectoris, fatal and non-fatal myocardial infarction, myocardial revascularization, and fatal or non-fatal stroke, was defined as the primary endpoint. Multivariable Cox proportional-hazards regression models were used to estimate the relative risk (HR) of CVD according to base-line blood-pressure categories. Results: In 2012, 1124 individuals (73.7% of the baseline sample), 719 women and 405 men (in 1997, aged 45±16 and 46±16 respectively) or their relatives in case of death, could be surveyed again in order to obtain information concerning incident CVD events. Cardiovascular event rates and HR values increased in a stepwise manner across the blood pressure categories (p for trend across categories <0.001 in both sex); however, in subjects aged ≥55 years a j-curve phenomenon was observed, showing the lowest incidence in the high-normal category. In all categories CVD events rates were higher for men. Conclusion: This study quantified relationships between BP and CVD starting from high-normal blood pressure in Argentina.Antecedentes: La hipertensión arterial es un reconocido factor de riesgo de enfermedad cardiovascular (ECV). Sin embargo, no hay información en Argentina que cuantifique la relación entre la presión arterial (PA) y ECV. Objetivo: Cuantificar el riesgo de ECV de acuerdo a categorías de PA. Método: Se realizó un estudio epidemiológico prospectivo en 1526 habitantes de la ciudad de Rauch (Buenos Aires, Argentina) entre octubre de 1997 y febrero de 2012. Los individuos fueron clasificados en las categorías de PA: 1-óptima, 2-normal, 3-normal-alta, 4-hipertensión grado 1, 5-hipertensión grado 2 y 6-hipertensión grado 3. Fue definido como punto final el primer evento de ECV (angina de pecho inestable, infarto fatal y no fatal, revascularización, y accidente cerebrovascular fatal y no fatal). El riesgo relativo (HR) de tener un evento fue estimado usando modelos de regresión multivariable de Cox. Resultados: En 2012, fueron re-encuestados 1124 individuos (73,7% de la muestra basal), 719 mujeres y 405 hombres, o sus parientes en caso de muerte (edad en 1997 45±16 y 46±16 años, respectivamente). Las tasas de ECV y los HR se incrementaron para cada categoría de PA por encima de la óptima (p &lt; 0.001 en ambos sexos); sin embargo, en sujetos mayores de 55 años se observó un fenómeno de curva en J, con la incidencia más baja en la categoría normal-alto. En todas las categorías la tasa de eventos fue mayor en hombres. Conclusión: Este estudio demostró y cuantificó la relación entre de PA y ECV a partir de PA normal alta en una población de Argentina.Facultad de Ciencias Médica

Should the first blood pressure reading be discarded?

We evaluated the consequences of excluding the first of three blood pressure (BP) readings in different settings: a random population sample (POS, n=1525), a general practice office (GPO, n=942) and a specialized hypertension center (SHC, n=462). Differences between systolic and diastolic BP (SBP and DBP) estimates obtained including and excluding the first reading were compared and their correlation with ambulatory BP monitoring (ABPM) was estimated. The samples were divided into quartiles according to the difference between the third and the first SBP (3-1ΔSBP). SBP decreased through sequential readings, 3-1ΔSBP was -5.5 ± 9.7 mm Hg (P<0.001), -5.1 ± 10.4 mm Hg (P<0.001) and -6.1 ± 9.3 mm Hg (P<0.001) for POS, GPO and SHC, respectively. However, individuals included in the top quartile of 3-1ΔSBP showed their highest values on the third reading. The mean SBP estimate was significantly higher excluding the first reading (P<0.001), but the differences among both approaches were small (1.5-1.6 mm g). Moreover, the correlation between SBP values including and excluding the first reading and daytime ABPM were comparable (r = 0.69 and 0.68, respectively). Similar results were observed for DBP. In conclusion, our study does not support the notion of discarding the first BP measurement and suggests that it should be measured repeatedly, regardless the first value.Facultad de Ciencias Médica

Insulin resistance: the linchpin between prediabetes and cardiovascular disease

The aim of this study was to test the hypothesis that cardiovascular disease occurs to the greatest extent in persons with prediabetes mellitus who are also insulin resistant. In 2003, 664 non-diabetic women (n = 457) and men (n = 207), aged 52 ± 16 and 53 ± 15 years, were surveyed during a programme for cardiovascular disease prevention. Fasting plasma glucose concentrations defined participants as having normal fasting plasma glucose (fasting plasma glucose <5.6 mmol/L) or prediabetes mellitus (fasting plasma glucose ⩾ 5.6 and <7.0 mmol/L). The tertile of prediabetes mellitus subjects with the highest fasting plasma insulin concentration was classified as insulin resistant. Baseline cardiovascular disease risk factors were accentuated in prediabetes mellitus versus normal fasting glucose, particularly in prediabetes mellitus/insulin resistant. In 2012, 86% of the sample were surveyed again, and the crude incidence for cardiovascular disease was higher in subjects with prediabetes mellitus versus normal fasting glucose (13.7 vs 6.0/100 persons/10 years; age- and sex-adjusted hazard ratio = 1.88, p = 0.052). In prediabetes mellitus, the crude incidences were 22.9 versus 9.6/100 persons/10 years in insulin resistant versus non-insulin resistant persons (age- and sex-adjusted hazard ratio = 2.36, p = 0.040). In conclusion, cardiovascular disease risk was accentuated in prediabetes mellitus/insulin resistant individuals, with a relative risk approximately twice as high compared to prediabetes mellitus/non-insulin resistant subjects.Facultad de Ciencias Médica