Forouzanfar MH, Alexander L, Anderson HR, et al, for the GBD 2013 Risk Factors Collaborators. Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks in 188 countries, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet. 2015 Dec 5. 386 (10010):2287-323. [Medline].

In a meta-analysis of pooled data from 19 prospective cohort studies involving 762,393 patients, Huang et al reported that, after adjustment for multiple cardiovascular risk factors, prehypertension was associated with a 66% increased risk for stroke, compared with an optimal blood pressure (< 120/80 mm Hg). [41, 42] Patients in the high range of prehypertension (130-139/85-89 mm Hg) had a 95% increased risk of stroke, compared with a 44% increased risk for those in the low range of prehypertension (120-129/80-84 mm Hg). [41, 42]
Insulin is released into the blood by beta cells (β-cells), found in the islets of Langerhans in the pancreas, in response to rising levels of blood glucose, typically after eating. Insulin is used by about two-thirds of the body's cells to absorb glucose from the blood for use as fuel, for conversion to other needed molecules, or for storage. Lower glucose levels result in decreased insulin release from the beta cells and in the breakdown of glycogen to glucose. This process is mainly controlled by the hormone glucagon, which acts in the opposite manner to insulin.[61]
According to the Mayo Clinic, doctors may use other tests to diagnose diabetes. For example, they may conduct a fasting blood glucose test, which is a blood glucose test done after a night of fasting. While a fasting blood sugar level of less than 100 milligrams per deciliter (mg/dL) is normal, one that is between 100 to 125 mg/dL signals prediabetes, and a reading that reaches 126 mg/dL on two separate occasions means you have diabetes.