title: Hidden chronic renal insufficiency and cardiovascular events in patients with hypertension in a primary care center.
abstract: OBJECTIVE
  The aims of this study were to evaluate whether hidden chronic renal insufficiency (CRI) may be considered an independent cardiovascular risk factor in patients with hypertension and to calculate cardiovascular risk in this population.
  
  
  METHODS
  A total of 756 hypertensive patients of ages from 35 to 74 years (mean 57.0 years; 58.2% women) and without evidence of cardiovascular disease were studied and followed during 10 years. Their glomerular filtration rate (GFR) was estimated using the simplified MDRD (result of the Modification of Diet in Renal Disease study) and Cockcroft-Gault formulas. Hidden CRI was identified by a GFR <60 mL/min/1.73 m(2) with normal serum creatinine concentration (<1.4 mg/dL men; <1.3 mg/dL women).
  
  
  RESULTS
  Of the patients with hidden CRI using the MDRD equation, 22% presented cardiovascular events (RR, 1.60; 95% confidence interval (CI), 1.06-2.43; p < 0.05). While the estimated coronary risk using the original Framingham function was similar in patients with and without hidden CRI (18.2%), using the REGICOR function it was higher in those with CRI (7.7 vs. 7.2%, p < 0.05). Logistic regression analysis showed that smoking, male sex, age, and diastolic blood pressure were predictors of cardiovascular events. The presence of hidden CRI was not a statistically significant predictor using either the MDRD (OR, 1.37; 95% CI, 0.72-2.61; p = 0.340) or the Cockcroft-Gault (OR, 1.05; 95% CI, 0.50-2.23; p = 0.893) formulas.
  
  
  CONCLUSIONS
  The hypertensive population of 35-74 years in age with hidden CRI showed a higher incidence of cardiovascular events, but hidden CRI may not be considered an independent cardiovascular risk factor.
authors.affiliation: Centro de Salud Universitario La Paz, Unidad Docente de Medicina Familiar y Comunitaria, Servicio Extremeño de Salud, Badajoz, Spain. fbuitragor@meditex.es
authors.forename: Francisco
authors.initials: F
authors.lastname: Buitrago
authors.forename: Juan Ignacio
authors.initials: JI
authors.lastname: Calvo-Hueros
authors.forename: Cristina
authors.initials: C
authors.lastname: Gómez-Jiménez
authors.forename: Lourdes
authors.initials: L
authors.lastname: Cañón-Barroso
authors.forename: Félix
authors.initials: F
authors.lastname: Suárez-González
authors.forename: Nicolás R
authors.initials: NR
authors.lastname: Robles
mesh_terms: D000328:Adult; D000368:Aged; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications*; D007676:Kidney Failure, Chronic / Q000150:complications*; D008297:Male; D008875:Middle Aged; D011320:Primary Health Care; D018570:Risk Assessment; D012307:Risk Factors