Does pharmacotherapy delay cognitive deterioration or delay disease onset of dementia syndromes?
Few studies evaluated delay of onset or delay in disease progression. A definite gap for evaluating disease onset (as defined by the selection of populations at risk such as MCI populations) has been identified in this review. Conversely, the need for good evaluation of disease progression in trials was also identified. In general, few studies evaluated subjects in more severe state of the disease. This suggests that a bias exists towards evaluating mild to moderate disease in the trials eligible in this systematic review. This in turn reflects the underlying assumption that the less severe groups are most likely to benefit from drug trials. Since so few studies have evaluated the more severe groups, this assumption may require some empirical justification in future research. Those studies that evaluated severe patients showed some potential for benefit. Future research in this area may require some consensus regarding the classification of severity levels. Three studies evaluating cer
