Nighttime masked uncontrolled hypertension tied to poor outcomes in CKD
NEW YORK 06/06 - Masked uncontrolled hypertension that occurs overnight is common in the chronic kidney disease (CKD) population and is associated with left ventricular hypertrophy (LVH) and decline in kidney function, new research shows.
The findings suggest the need for greater use of ambulatory blood pressure monitoring (ABPM) in patients with CKD and hypertension, even in patients with controlled office hypertension, the study team says.
Masked uncontrolled hypertension (MUCH) overnight often goes undetected among patients with controlled office blood pressure, but little attention has been paid to patients with CKD and nighttime MUCH, they point out in JAMA Network Open.
To investigate, they studied 675 patients with CKD not requiring dialysis, including 19% with controlled hypertension, 43% with sustained hypertension and 38% with MUCH, assessed by office and ambulatory blood pressure monitoring.
The MUCH group was further subdivided into isolated nighttime MUCH (23%) and day-night MUCH (13%).
Among patients with MUCH, two (1%) had isolated daytime MUCH, 154 (63%) had isolated nighttime MUCH, and 88 (36%) had day-night MUCH.
During a median follow-up of 39 months, 130 kidney events, including 97 end-stage kidney disease (ESKD) events, occurred.
In multivariate-adjusted analysis, there was a significant association between day-night MUCH and LVH (OR, 3.26) and between isolated nighttime MUCH and the composite kidney outcome of ESKD and at least a 50% reduction in estimated glomerular filtration rate (HR, 4.27).
"Our findings support the value of 24-hour ABPM in the management of hypertension, especially in patients with CKD," write Dr. Nan Chen of Ruijin Hospital, in Shanghai, China, and colleagues.
"However, clinical use of ABPM has been limited in the past by variable factors, including economic and human cost. Meanwhile, management of nighttime MUCH still lacks clinical experience reports or evidence-based medical research," they point out.
"Future clinical trials are needed to explore effective interventions on nighttime MUCH and to assess the effect of lowering BP on clinical outcomes among patients with CKD," they say.
The authors of a linked commentary note that hypertension is "the most important modifiable risk factors for cardiovascular morbidity and mortality" in the CKD population.
"Accumulating evidence suggests that masked uncontrolled hypertension (MUCH) is consistently associated with higher cardiovascular event risk compared with patients with controlled hypertension," write Dr. Laura Mayeda and Dr. Matthew Rivara of the University of Washington, in Seattle.
ABPM captures nighttime BP values and is the only tool that can simultaneously identify white-coat hypertension, MUCH, and nighttime hypertension, they point out.
The new current study "adds to the growing body of evidence supporting the clinical use of ABPM in patients with CKD, at the very least as a way to improve risk prediction among patients with CKD and controlled clinic BPs," the editorialists say.
"Additionally, as more stringent BP targets are used by nephrologists and other clinicians when treating patients with CKD and hypertension, ABPM has the potential to improve accuracy and safety of intensive targeted BP interventions," they add.
They write, "one point is clear - when it comes to CKD and hypertension management, MUCH more is needed than just clinic BP readings!"