The purpose of this study is to learn about effects of remote ischemic conditioning on blood pressure in older patients with essential hypertension.

Current studies have shown that remote ischemic conditioning can improve vascular endothelial function and inhibit sympathetic nervous system activity. Thus it may provide some organ protection as well as anti-hypertensive effects. The purpose of this study is to learn about effects of remote ischemic conditioning on blood pressure in older patients with essential hypertension.

Inclusion Criteria:

• 1) Age ≥65 years and ≤85 years, regardless of gender;
• 2) History of essential hypertension and clinical systolic blood pressure ≥ 140 mmHg, regardless of whether they are receiving antihypertensive medication;
• 3) Willing to participate and sign the informed consent.

Exclusion Criteria:

• 1) Secondary hypertension;
• 2) Clinical blood pressure ≥ 180/110 mmHg or 24-hour mean arterial pressure ≥ 170/100 mmHg;
• 3) Severe organ dysfunction or failure;
• 4) Severe hematologic disorders or significant coagulation abnormalities;
• 5) History of atrial fibrillation or myocardial infarction within 6 months;
• 6) Individuals who had contraindication of remote ischemic conditioning, such as severe soft tissue injury, fracture or vascular injury in the upper limb, acute or subacute venous thrombosis, arterial occlusive disease, subclavian steal syndrome, etc;
• 7) Individuals who will or have received anticoagulant therapy with drugs such as dabigatran, rivaroxaban, warfarin, etc;
• 8) Those who are participating in other clinical research or has participated in other clinical research or has participated in this study within 3 months prior to enrollment;
• 9) Other conditions that the researchers think are not suitable for the project.