SUKKUR - World Hypertension Day was also observed in Sukkur on Monday to create awareness in the public and to lay stress on prevention methods to avoid its harmful effects. Talking to media, prominent surgeon, Dr Altaf Awan said hypertension is a condition called high blood pressure during which the arterial blood pressure raises to high level from the normal level (120/80 mmHg). He said that it is medical condition called as silent killer as it does not show any clear symptoms; however, severe hypertension show some symptoms of headaches, sleepiness, palpitation, blurred vision, fatigue, dizziness, confusion, ringing sensation in the ears, breathing difficulty, irregular heartbeat which may lead to even coma. According to Dr Awan, it is divided in two types (primary or essential hypertension and secondary hypertension) on the basis of its causing factors. The primary hypertension is more common type; however, its causes are unknown, he said. Whereas, causes of secondary hypertension are kidney damage, adrenal gland over-activity, sleep apnea syndrome, tumours, recreational drugs, thyroid gland dysfunctional, aortic coarctation, pregnancy-related conditions, over or wrong medications, alcoholic drinks, bad food and etc, he added.