Chronic Diseases (Diabetes, Kidney) & Nighttime Hypertension

Relationship bewteen diabetes and nocturnal (nighttime) hypertension is a topic that I am keenly interested as my family has a history of diabetes. I have read quite a bit on the subject of diabetes and it is only recently I learned that nighttime hypertension (non-dipper) for a diabetic increases significantly the risk of having cardiovascular and kidney. Many research report were published in the past 3-5 years related to this particular topic.

Night time blood pressure variability is a strong predictor for cardiovascular events in patients with type 2 diabetes. This article was published in 2009 American Journal of Hypertension, which is the journal in the field of hypertension. It described an experiment consisted of 300 patients with diabetes and the objective was to study if daytime and nighttime blood pressure variation were good predictors of cardiovascular disease. The result was surprising - daytime blood pressure was not a predictor at all, while nighttime blood pressure was an independent predictor of future events. This experiment showed the need for diabetes to monitor their nighttime blood pressure using an ambulatory blood pressure monitor.

Nocturnal hypertension: will control of nighttime blood pressure prevent progression of diabetic renal disease? This article reported that patients with type 1 diatetes would have an increase of nighttime blood pressure prior getting to the microalbuminuric phase of nephropathy (a kidney disease). The microalbuminuric phase is the beginning of the disease when small amounts of albumin leaks into the urine. This study suggested that nighttime hypertension may be an important early warning of diabetic nephropathy and controlling nighttime hypertension with drugs may be key to patients' health.

High blood pressure makes the heart work harder and the extra pressure can damage blood vessels throughout the body. When the kidney blood vessels are damaged, the kidney would not be able to remove wastes and extra fluid from the body. The extra fluid would raise in turn raise the blood pressure. This is a vicious cycle.

Technical report of ambulatory blood pressure monitor in chronic kidey disease This article appeared in KDOQI Clinical Practice Guidelines on Hypertension and Antihypertensive Agents in Chronic Kidney Disease form National Kidney Foundation. The guideline suggested the routine use of ambulatory blood pressure monitor in chronic kidney disease. The following listed some of the key findings.

  • The level of blood pressure measurement using ABPM correlates better with target-organ injury than office measurements.
  • ABPM also provides a measure of the percentage of blood pressure readings that are elevated, of the overall blood pressure load, and of the extent of blood pressure reduction during sleep.
  • In most individuals, blood pressure decreases by 10% to 20% during the night; those in whom such reductions are not present are at increased risk for cardiovascular events.