Blood pressure often increases in stages. A person in her thirties may have mild to moderately elevated blood pressure readings. As she ages, blood pressure may continue to slowly rise. If someone develops high blood pressure before the age of 50, the risk of heart attack and stroke is greatly increased. If untreated, high blood pressure can reduce life expectancy by 10 or more years.
Pulse pressure (the difference between systolic and diastolic blood pressure) is frequently increased in older people with hypertension. This can mean that systolic pressure is abnormally high, but diastolic pressure may be normal or low a condition termed isolated systolic hypertension.[59] The high pulse pressure in elderly people with hypertension or isolated systolic hypertension is explained by increased arterial stiffness, which typically accompanies aging and may be exacerbated by high blood pressure.[60] 

Much is being made of the fact that the new definitions of high blood pressure will mean roughly half of all US citizens will be considered to have high blood pressure, but when you really look at the numbers, as cardiologists already have, not that many more people will actually be advised to take medications. Although the public has good reason to be suspicious of “big pharma,” that’s not what this is about.
Historically the treatment for what was called the "hard pulse disease" consisted in reducing the quantity of blood by bloodletting or the application of leeches.[152] This was advocated by The Yellow Emperor of China, Cornelius Celsus, Galen, and Hippocrates.[152] The therapeutic approach for the treatment of hard pulse disease included changes in lifestyle (staying away from anger and sexual intercourse) and dietary program for patients (avoiding the consumption of wine, meat, and pastries, reducing the volume of food in a meal, maintaining a low-energy diet and the dietary usage of spinach and vinegar).
A 2015 review of several studies found that restoring blood vitamin D levels by using supplements (more than 1,000 IU per day) reduced blood pressure in hypertensive individuals when they had existing vitamin D deficiency.[167] The results also demonstrated a correlation of chronically low vitamin D levels with a higher chance of becoming hypertensive. Supplementation with vitamin D over 18 months in normotensive individuals with vitamin D deficiency did not significantly affect blood pressure.[167]

^ Jump up to: a b Acierno, Mark J.; Brown, Scott; Coleman, Amanda E.; Jepson, Rosanne E.; Papich, Mark; Stepien, Rebecca L.; Syme, Harriet M. (2018-10-24). "ACVIM consensus statement: Guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats". Journal of Veterinary Internal Medicine. 32 (6): 1803–1822. doi:10.1111/jvim.15331. ISSN 1939-1676. PMC 6271319. PMID 30353952.
Preeclampsia is elevated blood pressure and the leakage of protein into the urine by the kidneys. Preeclampsia can be dangerous to both mother and baby. High blood pressure during pregnancy may lead to decreased blood flow to the placenta, placental abruption, premature delivery, or future cardiovascular disease. After the baby is born, high blood pressure during pregnancy usually returns to normal levels.
You are considered to have hypertension if your systolic blood pressure measurements are between 130 and 139 or your diastolic measurement falls between 80 and 89. At this level of blood pressure you may not have any symptoms. When blood pressure reaches 180/120 or higher, a serious condition known as a malignant hypertension or hypertension crisis may occur. This can lead to stroke, kidney damage, heart attacks, or loss of consciousness. If you measure your blood pressure and it is this high, rest a few minutes and measure again. If it remains high, call 911.
^ Saiz, Luis Carlos; Gorricho, Javier; Garjón, Javier; Celaya, Mª Concepción; Muruzábal, Lourdes; Malón, Mª del Mar; Montoya, Rodolfo; López, Antonio (2017-10-11). "Blood pressure targets for the treatment of people with hypertension and cardiovascular disease". Cochrane Database of Systematic Reviews. 10: CD010315. doi:10.1002/14651858.cd010315.pub2. PMID 29020435.