Telemedicine Home Blood Pressure Measurements and Progression of Albuminuria in Elderly People With Diabetes

Abstract

Abstract-We assessed whether home blood pressure monitoring improved the prediction of progression of albuminuria when added to office measurements and compared it with ambulatory blood pressure monitoring in a multiethnic cohort of older people (nϭ392) with diabetes mellitus, without macroalbuminuria, participating in the telemedicine arm of the Informatics for Diabetes Education and Telemedicine Study. Albuminuria was assessed by measuring the spot urine albumin:creatinine ratio at baseline and annually for 3 years. The ambulatory sleep:wake systolic blood pressure ratio was categorized as dipping (ratio: Յ0.9), nondipping (ratio: Ͼ0.9 to 1.0), and nocturnal rise (ratio: Ͼ1.0). In a repeated-measures mixed linear model, after adjustment that included office pulse pressure, home pulse pressure was independently associated with a higher follow-up albumin:creatinine ratio (Pϭ0.001). That association persisted (Pϭ0.01) after adjusting for 24-hour pulse pressure and nocturnal rise, which were also independent predictors (Pϭ0.02 and Pϭ0.03, respectively). Cox proportional hazards models examined the progression of albuminuria (nϭ74) as defined by cutoff values used by clinicians. After the adjustment for office pulse pressure, the hazards ratio (95% CI) per 10-mm Hg increment of home pulse pressure was 1.34 (range: 1.1 to 1.7; Pϭ0.01). Home pulse pressure was not an independent predictor in the model including ambulatory monitoring data; a nocturnal rise was the only independent predictor (Pϭ0.035). Cox models built separately for home pulse pressure and ambulatory monitoring exhibited similar calibration and discrimination. In conclusion, nocturnal blood pressure elevation was the strongest predictor of worsening albuminuria. Home blood pressure measurements added to office measurements and may constitute an adequate substitute for ambulatory monitoring. Key Words: albuminuria Ⅲ diabetes mellitus Ⅲ home blood pressure Ⅲ ambulatory blood pressure A lbuminuria is independently associated with cardiovascular morbidity and mortality in people with and without diabetes mellitus. [1][2][3][4][5][6] An increase in albuminuria is associated with higher cardiovascular morbidity and mortality, 7 whereas a decrease achieved through drug therapy is associated with better outcomes. 8 Albuminuria is prevalent in older and middle-aged people with type 2 diabetes mellitus, 9 -11 in whom cardiovascular and renal complication rates are the highest. 12-14 Thus, it is of particular importance to identify predictors of worsening albuminuria in older people with diabetes mellitus.Ambulatory blood pressure monitoring (ABPM) predicts progression of albuminuria better than office blood pressure (BP) in people with diabetes, [15][16][17][18][19] and 24-hour pulse pressure (PP) and a nocturnal increase in BP are the most informative variables in elderly diabetic subjects. 18,19 However, ABPM is not yet considered the standard of care for the management of hypertension. On the other hand, a growing number of patients are successfully monitori...

Prediction of albuminuria by different blood pressure measurement methods in type 1 diabetes: a pilot study

“…27 A study in 50 type 2 diabetics showed HBP to be more predictive of microalbuminuria and proteinuria than CBP, 28 and another one in elderly type 2 diabetics showed that HBP is as good as ABP in predicting the progression of albuminuria. 29 However, when both methods were entered in the same model, HBP lost its significance and nighttime ABP was the only independent predictor of worsening albuminuria. 29 Previous studies in diabetics 30,31 and nondiabetics 22 have shown that nighttime ABP gives the strongest correlations with albuminuria.…”

“…29 However, when both methods were entered in the same model, HBP lost its significance and nighttime ABP was the only independent predictor of worsening albuminuria. 29 Previous studies in diabetics 30,31 and nondiabetics 22 have shown that nighttime ABP gives the strongest correlations with albuminuria. This was not confirmed in this study, yet the findings do support the view that ABP is superior to clinical and also to home measurements in predicting albuminuria in type 1 diabetes.…”

Blood Pressure Variability, Cardiovascular Risk, and Risk for Renal Disease Progression

“…Subjects in whom a nocturnal decrease in BP is blunted have been reported to have a higher prevalence of subclinical organ damage [4] and an increased risk of CV events [72] and mortality [58], which is even higher in patients in whom BP increases rather than decreases at night (so called risers or "inverted dippers"). When focusing on the kidney, longitudinal studies have found a non-dipping and/or a reverse dipping pattern of nighttime BP to be an independent predictor of the development and progression of microalbuminuria [68,70,[73][74][75], an increase in proteinuria [76], decline in renal function (reductions in GFR and/or increase in creatinine levels) [46,[77][78][79][80], faster progression of CKD and poor renal prognosis (i.e., progression to ESRD) [66,[81][82][83][84].…”

Comparative Prognostic Role of Nighttime Blood Pressure and Nondipping Profile on Renal Outcomes

“…In addition, since there are follow-up studies in diabetic subjects with or without hypertension that established associations of nondipping status with both glomerulopathy and increased urinary albumin excretion [47,51], a post-hoc analysis that included patients with chronic kidney disease showed no correlation of nondipping status with the decline in renal function [52]. Taking this issue a step further, in elderly nonmacroalbuminuric diabetic patients the progression of albuminuria was associated solely with the phenotype of reverse nocturnal dipping and not with the nondipping pattern [53,54]. Lastly, 177 kidney transplanted patients underwent ABPM after their grafts were independently functioning and were followed for at least 48 weeks after the intervention.…”