The daily pattern for blood pressure readings usually peaks in the afternoon, falling at night and slowly rising from the time a person awakens. Blood pressure usually starts to drop once again in the late afternoon and early evening. If this pattern is different, it can signify a dangerous underlying medical condition or problem. In the March 2003 Neurology Review Online Journal, author Susan Jeffrey reported the results of a research study in Chicago IL. Researchers found that for every 10 mm Hg rise in systolic pressure in the morning readings compared to the lowest pressure measured, meant a 25 percent increase risk of stroke.
Mayo Clinic physicians found that those patients who included caffeine and tobacco in their daily intake would have an increased risk of having high blood pressure readings in the morning, within two hours of awakening. Caffeine is found in coffee, tea, soda, chocolate and some medications used to treat migraine headaches. Tobacco use includes chewing tobacco and pipe smoke.
The National Heart Lung and Blood Institute lists cold medications, hormone replacement, birth control and asthma medications as products that commonly cause an overall rise in blood pressure, resulting in higher-than-normal readings in the morning hours. When an individual starts with high blood pressure, the overall rise can be even greater. Mayo Clinic doctors also list blood pressure medications, which do not work for the entire 24 hours, as a cause of an early morning spike in blood pressure readings.
Mayo Clinic physicians counsel their patients that night shift work and excess stress can also change the circadian rhythm of blood pressure readings, making them higher in the early morning hours. Individuals who work the night shift, eat during the night hours and get less sleep in the daytime hours, contributing to the morning rise in blood pressure. Stress causes an overall increase in blood pressure, but will be responsible for an early morning peak when stress reduces the amount of sleep at night and individuals remain anxious through the night hours.
Elite athletes are at an increased risk of developing early rises in blood pressure when they cross the line from training to overtraining. In his article for YSI Limited, a UK company specializing in sensory technology, Dr. Robson advises that overtrained athletes exhibit increased blood pressure morning readings, elevated heart rate, decreased appetite, lethargy, depression and loss of motivation. Elevated morning blood pressure caused by overtraining can be resolved when the athlete takes a much needed rest.