Taking a blood pressure pill at bedtime instead of in the morning might be healthier for some high-risk people.

New research, published in the December issue of the American Journal of Kidney Diseases, suggests the simple switch may normalize patterns of blood pressure in patients at extra risk from both heart and kidney disease.

In two months, nearly 90 per cent of high-risk patients taking their medication before bed saw their nighttime blood pressure drop an average of seven points, without side effects or increase in daytime blood pressure.
(CBC)

Why? When it comes to blood pressure, you want to be a dipper. In healthy people, blood pressure dips at night, by 10 to 20 per cent. Scientists don't know why, but suspect the drop gives arteries a little rest.

People with high blood pressure that doesn't dip at night fare worse than other hypertension sufferers, developing more serious heart disease. Moreover, heart and kidney disease fuel each other — and people with chronic kidney disease seem most prone to non-dipping. In addition to heart problems, they're at extra risk of their kidney damage worsening to the point of dialysis.

Most blood pressure patients need two or three medications. So Italian researchers performed an easy test: They told 32 non-dippers with kidney disease to switch one of those drugs from a morning to a bedtime dose.

In two months, nearly 90 per cent of these high-risk patients had turned into dippers. Their nighttime blood pressure dropped an average of seven points, without side effects or an increase in daytime blood pressure.

Better, a key sign of kidney function improved significantly, too, Dr. Roberto Minutolo of the Second University of Naples reports in the December issue of the American Journal of Kidney Diseases.

Doctors at Baltimore's Johns Hopkins University are now planning a larger study to see whether a bedtime switch really could give certain people healthier hearts and kidneys.

High blood pressure affects one in five Canadians, according to the Heart and Stroke Foundation of Canada. An estimated two million Canadians have kidney disease or are at risk.