The Pattern of Nondipping and Urinary Albumin Excretion
To the Editor:
We read the article published recently by Oliveras et al1 with interest. The authors showed that, in resistant hypertensive patients, there were significant associations of microalbuminuria with older age, reduced estimated glomerular filtration rate, increased nighttime systolic blood pressure, and elevated daytime, nighttime, and 24-hour diastolic blood pressures. In a logistic regression analysis, after age and sex adjustment, elevated nighttime systolic blood pressure (multivariate odds ratio: 1.014 [95% CI: 1.001 to 1.026]; P=0.029) and reduced estimated glomerular filtration rate (multivariate odds ratio: 2.79 [95% CI: 1.57 to 4.96]; P=0.0005) were independently associated with the presence of microalbuminuria. The authors concluded that microalbuminuria is better associated with increased nighttime systolic blood pressure than with any other office and 24-hour ambulatory blood pressure monitoring parameters.1
In a recently published article we examined the relationship between 24-hour urinary albumin excretion rate and the pattern of nondipping (isolated systolic nondipping, isolated diastolic nondipping, and both systolic and diastolic nondipping). The median urinary albumin excretions of isolated systolic nondippers, isolated diastolic nondippers, and both systolic and diastolic nondippers were 8.45, 7.70, and 25.50 mg/d, respectively (P=0.001). Subgroup comparison of patients revealed that urinary albumin excretion was higher in patients with both systolic and diastolic nondippers when compared with dippers (P<0.0001), isolated systolic nondippers (P=0.001), and isolated diastolic nondippers (P=0.017). We concluded that not only nondipping itself but also nondipping profile may be related to urinary albumin excretion in essential hypertensive patients.2
By the light of these findings we wonder whether Oliveras et al1 could give more information regarding whether the patterns of nondipping (isolated systolic nondipping, isolated diastolic nondipping, and both systolic and diastolic nondipping), apart from absolute ambulatory blood pressure measurements, were related to microalbuminuria.
Ferhuniye Mah, Hastane Cad
Department of Nephrology
Konya Numune State Hospital
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- © 2011 American Heart Association, Inc.