March 1, 2005Circulation239 citations
View Full PaperLow-Grade Albuminuria and the Risks of Hypertension and Blood Pressure Progression
Key Result
Participants in the highest quartile of urine albumin-creatinine ratio had a higher risk of developing hypertension compared with the lowest quartile (adjusted OR 1.93, P=0.006).
Key Points
- This research aims to investigate the relationship between urinary albumin excretion and the risks of hypertension and blood pressure progression in nondiabetic individuals.
- Analyzed 1499 nonhypertensive individuals without diabetes over a mean follow-up of 2.9 years.
- Measured urinary albumin-creatinine ratio as a predictor of hypertension and blood pressure progression.
- Conducted multivariable logistic regression adjusted for known risk factors.
- 15% of participants developed hypertension during follow-up.
- Individuals in the highest UACR quartile had an approximately 2-fold risk of hypertension (adjusted OR 1.93, P=0.006).
- Participants in the highest UACR quartile had a 1.5-fold risk of blood pressure progression (adjusted OR 1.45, P=0.03).
Study Design
Type
Cohort (n=1,499)
Structured PICO
Does higher urinary albumin excretion predict incident hypertension and blood pressure progression in nonhypertensive individuals without diabetes?
P
Population
1,499 nonhypertensive individuals without diabetes (58% women) followed for a mean of 2.9 years.
E
Exposure
Higher urine albumin-creatinine ratio (UACR) (highest quartile: men >6.66 mg/g; women >15.24 mg/g)
C
Comparator
Lowest UACR quartile
O
Outcome
Incident hypertension and blood pressure progression (defined by the sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure)surrogate
Low-grade albuminuria, even below the conventional threshold for microalbuminuria, independently predicts the development of hypertension and blood pressure progression in nondiabetic individuals.
Main Result
Odds Ratio: 1.93
p-value: p=0.006
Abstract
BACKGROUND: It has been postulated that glomerular hyperfiltration and endothelial dysfunction are early features of essential hypertension that may antedate blood pressure elevation. Microalbuminuria, a marker of glomerular hyperfiltration and endothelial dysfunction, has been described in individuals with established hypertension, but its role as a biomarker of preclinical stages of this disease has not been investigated prospectively. METHODS AND RESULTS: We examined the association between urinary albumin excretion and the risks of hypertension and blood pressure progression in 1499 nonhypertensive individuals (58% women) without diabetes. During a mean follow-up of 2.9 years, 230 participants (15%) developed hypertension and 499 (33%) progressed to a higher blood pressure category (defined by the sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure). In multivariable logistic regressions that adjusted for known risk factors, the urine albumin-creatinine ratio (UACR) was a significant predictor of incident hypertension (adjusted OR 1.20, 95% CI 1.01 to 1.44, per 1-SD increment in log UACR). Compared with those in the lowest UACR quartile, participants in the highest quartile (men: >6.66 mg/g; women: >15.24 mg/g) had an approximately 2-fold risk of developing hypertension (adjusted OR 1.93, P=0.006) and 1.5-fold risk of blood pressure progression (adjusted OR 1.45, P=0.03). CONCLUSIONS: Urinary albumin excretion predicts blood pressure progression in nondiabetic, nonhypertensive individuals incrementally over established risk factors and at levels well below the conventional threshold for microalbuminuria. UACR may be a useful biomarker for identifying individuals most likely to develop hypertension.