RIVASTIGMINE ON

NLH - Mental health - Impact of rivastigmine on costs and on time spent in caregiving for families of patients with Alzheimer's disease The objectives of the study were two-fold. The authors sought to observe the extent to which disease severity relates to care giver time. This information was then used to estimate the effects of rivastigmine treatment on hours spent in care-giving and associated costs. The perspective adopted in the analysis was that of the caregiver responsible for time spent care-giving in the informal care setting, and that of the party responsible for the costs associated with formal care in the form of institutionalisation.In order to estimate the burden associated with care-giving according to disease progression, data were collected from a prospective observational study of AD patients. Even though the authors failed to report the proportion of patients in each stage of AD, a statistically significant correlation was observed between the MMSE scores and hours of care-giving, as measured by the CAS. However, the authors did not report any characteristics of the patient sample. Therefore, there is a high probability of bias and confounding factors that may have affected the result. The delay of disease progression associated with rivastigmine treatment was derived from a study using clinical trial data for over 1,000 patients recruited in two placebo-controlled international trials, which were undertaken in 67 centres. Although the internal validity of these two trials appears to have been high, the results of these trials, which lasted for 26 weeks, were then extrapolated to a 2-year period. Thus, there is the potential for introducing extrapolation bias. Comprehensive sensitivity analyses were conducted to mitigate these possible biases.