Pharmacotherapy and prevention of vascular dementia

Vascular dementia (VAD), the second most common form of dementia after Alzheimer's disease (AD) is characterized by a cognitive deficit of cerebrovascular origin. As for AD, the main proposed treatment is based on cholinesterase inhibitors. However, randomized clinical trials (RCTs) with cholinesterase inhibitors in VAD reported modest - though sometimes statistically significant - clinical efficacy. Non-cholinergic drugs with diverse rationales and mechanisms of action have also been tested in a few RCTs for VAD; the outcomes measured are variable and the evidence of efficacy is weak. The limitations of pharmacological treatment for VAD have prompted a different strategy, i.e. primary prevention aimed at reducing vascular risk factors. Several epidemiological studies reported associations of hypertension, type 2 diabetes, obesity, and inflammation with VAD and in some cases, AD. These all coincide with those of stroke, which in turn is an established factor for cognitive decline and VAD. Here too, only a few RCTs have looked at prevention of these factors, except hypertension. Some pharmacological classes are particularly promising from the clinical and experimental viewpoints: Ca2+ channel blockers and drugs affecting the renin-angiotensin system may act independently of the effects on blood pressure. Despite some conflicting results and the need for further work, the control of risk factors might prevent cognitive decline and VAD in the elderly. The benefit of tackling vascular factors is probably larger when also considering the prevention of stroke. The objective of this review is to analyze the pharmacological treatment and prevention of VAD and their outcome. The literature on Pubmed from 1980 to 2009 was examined.