Protective effect of anti-hypertensive treatment on cognitive function in essential hypertension: analysis of published clinical data.

Hypertension is a risk factor for stroke and may also contribute to the development of vascular cognitive impairment (VCI) and vascular dementia (VaD). Cognitive complications of hypertension and the influence of anti-hypertensive treatment were underestimated until recently. In this paper, trials investigating the effect of anti-hypertensive treatment on cognitive function were evaluated. Analysis of these studies revealed that until approximately 1990-1995 investigations have assessed primarily if anti-hypertensive treatment impaired cognitive function. Only more recent studies have investigated positive effects on cognition of anti-hypertensive medication. Drugs more extensively evaluated were diuretics, beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, sartanes and Ca(2+) channel blockers. Available studies have confirmed that elevated diastolic blood pressure or pulse pressure and isolated systolic hypertension play an important role in the development of cognitive impairment. Randomized placebo-controlled trials have provided evidence that reduction of hypertension safely and effectively decreases morbidity and mortality rates and cognitive complications of hypertension. Ca(2+) channel blockers and ACE inhibitors have been shown to be effective and probably better than diuretics and beta-blockers on cognitive domains of hypertension. More extensive investigations could contribute to establishing optimal choice and drug dosage for the treatment of cognitive complications of hypertension.