Arterial stiffness : from isolated systolic hypertension to syncope

Isolated systolic hypertension (ISH) is the predominant form of hypertension in the elderly. The pathophysiology includes a plethora of factors; however, the stiffening of large arteries, leading to wider pulse pressure and faster propagation of the pressure pulse wave, are at the core of the disease. It has been shown that higher systolic blood pressure (SBP), pulse pressure, and pulse wave velocity are associated with a greater risk of cardiovascular complications, including a greater risk of dementia. In elderly patients, the relationship between SBP and the risk of mortality starts increasing at about 160 mmHg. A number of clinical trials were performed in populations of patients which included the elderly, however only four trials were specifically dedicated to answer the question of whether the active treatment of ISH (SHEP, Syst-Eur, Syst-China) or treatment of octogenarian hypertensive patients (HYVET) lowers cardiovascular risk in the elderly patient. They all showed that regimens based on thiazide-like diuretics, dihydropyridine calcium channel blockers, or angiotensin-converting enzyme inhibitors are capable of reducing the risk along with the appropriate reduction of SBP. This is widely reflected in the current European guidelines, with the addition of angiotensin receptor blockers. Nevertheless, the debate on the appropriate blood pressure goal is ongoing. However, none of the trials in the elderly had an average SBP lowered to less than 140 mmHg, and the overwhelming evidence suggests that in patients above the age of 70 with overt cardiovascular disease, a SBP less than 130 mmHg may be associated with an increase in risk.