Hypertension is estimated to cause 4.5% of current global disease burden. Recent surveys estimate indicated one in three Americans has hypertension. Hypertension is already a highly prevalent cardiovascular risk factor worldwide because of increasing longevity and prevalence of contributing factors such as obesity. Hypertension is an underlying cause of heart attacks, strokes, kidney disease and heart failure.Blood pressure-induced cardiovascular risk rises continuously across the whole blood pressure range. Starting at a blood pressure of 115/80,research shows that the risk of a heart attack or stroke doubles with every 20-point increase of systolic pressure, the top number, or 10-point increase of diastolic pressure, the bottom number.Since publication of the WHO/ISH (World Health Organization/International Society of Hypertension) Guidelines for the Management of Hypertension in 1999,more evidence has become available to support a systolic blood pressure threshold of 140mmHg for even'low-risk'patients. Whereas the treatment of hypertension has been shown to prevent cardiovascular diseases and to extent and enhance life, hypertension remains inadequately managed everywhere. In high-risk patients there is evidence for lower thresholds. Lifestyle modification is recommended for all individuals. There is evidence that specific agents have benefits for patients with particular compelling indications, and that monotherapy is inadequate for the majority of patients.For patients without a compelling indication for a particular drug class,on the basis of comparative trial data,availability,and coat, a low dose of diuretic should be considered for initiation of therapy.In most places a thiazide diuretic is the cheapest option and thus most cost effective, but for compelling indications where other classes provide additional benefits,even if more expensive, they may be more cost effective.In high-risk patients who attain large benefits from treatment,expensive drugs may be cost effective,but in low-risk patients treatment may not be cost-effective unless the drugs are cheap.

High blood pressure is becoming increasingly resistant to drugs that lower it. The problem is not that the medications have stopped working.Instead, many blood-pressure patients are sicker to begin with and require more drugs, at greater dosages, to manage their conditions.Resistant hypertension is defined as blood pressure that remains above clinical goals, even after a patient has been put on three or more different classes of medications.Additionally, patients whose blood pressure can be lowered to normal on four or more drugs should be considered resistant and should be closely monitored. It became more likely with advanced age, weight gain, a diet high in sodium,sleep apnea or chronic kidney disease. 20 to 30 percent could not control their blood pressure with three or more drugs, even when taking them exactly as prescribed. The 20 to 30 percent cohort appears to be growing. A large study in 2006 from Stanford found that the number of blood-pressure patients who were prescribed three or more drugs had increased over 12 years, to 24 percent from 14 percent. If patients need that many drugs, they are likely to be at greater risk for illness even if they lower their blood pressure to normal.These patients have usually had high blood pressure for some time and, as a result, have more organ damage.

Since drugs have side effects, patients might prefer physical therapy. As Ouyang et al.(2004) have reviewed, there is therapeutic effects on hypertension of acupuncture at acupoints of stomach meridian of foot yang-ming, large intetine meridian of hand yang-ming or small intestine meridian of hand tai-yang, or all of the meridians. There are acupoints of the three meridians inside/around nose which can be irradiated by intranasal LIL so that there might be therapeutic effects of ILILT on hypertension according to meridian mediated ILILT hypothesis (MIH) as discussed in <<Intranasal Low Intensity laser Therapy>> chapter 3.

Reactive oxygen species (ROS) play an important role in the development of hypertension.This is due, in large part, to excess production of oxidants, to decrease nitric oxide (NO) bioavailability, and to decreased antioxidant capacity in the vasculature and kidneys. The increased .O2 - levels inactivate the vasodilator NO leading to endothelial dysfunction and vasoconstriction, characteristic of hypertension. Although studies in humans have not been as convincing as those in experimental models, there is evidence that oxidative stress is increased in patients with essential hypertension, renovascular hypertension, malignant hypertension, salt-sensitive hypertension, cyclosporine-induced hypertension, and preeclampsia. Hypertensive patients exhibit a significantly higher production of plasma hydrogen peroxide (H2O2) than normotensive subjects. Based on experimental evidence of the importance of oxidative stress in vascular damage, there has been enormous interest in developing steategies that target ROS in the treatment of hypertension. Therapeutic approaches that have been considered include mechanisms 1) to increase antioxidant capacity,2) to increase NO bioavailability, and 3) to reduce ROS generation by decreasing activity of .O2 - generating enzymes. Overall results of clinical studies investigating antioxidant effects have been disappointing given the consistent and promising fingings from experimental investigations, clinical observations, and epidemiological data. It might be due to their disturbing oxidant-antioxidant homeostasis (OAH). ILILI has been recom- mended to rehabilitate OAH so that its antioxidant defense might be enhanced. Moreover, as shown in chapter 3, malformation rate of erythrocy- tes, the level of viscosity at lower shear rates and hematocrit, and serum lipid decreased, respectively, red cell deformability (RCD) increased, and circulation was improved after ILILT.Therefore, there might be therapeutic effects of ILILT on hypertension.

Low intensity 632.8nm He-Ne laser irradiation (LHNL) on the renying acupoint (ST 9) (Figs.5 and 7) of both sides of the patients with hypertension has been found to improve the microcirculation and blood pressure of the patients.Low intensity 810nm diode laser irradiation on neiguan acupoint (PC 6) (Fig.6) of the patients with hypertension has also been found improve their symptom. These suggested the acupuncture of low intensity laser irradiation (LIL) of ILILT and the skin-contact electric acupuncture of low frequency pulse on the acupoints, renying and neiyuan, might promote the therapeutic effects of ILILT on hypertension.