Elderly people with swelling of the lower limbs consider physiological factors, pathological factors such as those caused by poor venous return of the lower limbs, if it is a single lower limb swelling, seen in lower limb venous embolism; if it is a double lower limb swelling, seen in cardiac insufficiency, renal disease, hypothyroidism and so on. 1. Physiological factors, such as poor blood circulation in the lower limbs caused by prolonged sitting and standing, causing swelling of the lower limbs; eating too salty, resulting in sodium retention, can also cause swelling of the lower limbs. 2. Pathologic factors Single lower limb edema in the elderly is mostly due to varicose veins in the lower limbs, poor venous return, venous valve insufficiency, and standing for a long time, which can be relieved after bed rest and elevation of the lower limbs; if the single lower limb edema is serious, venous embolism in the lower limbs may occur, which should be consulted in time. If it is double lower limb edema, it is mostly seen in cardiac insufficiency, hepatic insufficiency, renal diseases such as renal failure, nephritis, etc.; there is also hypothyroidism, the patient is mostly generalized edema, mostly accompanied by underlying diseases. If the elderly lower limb edema is difficult to relieve, or other discomforts, we should go to the hospital in time, to clarify the cause of the disease, and follow the doctor’s instructions for treatment.