Relations between cognitive status and medication adherence in patients treated for memory disorders.

Medication adherence has been increasingly recognized as an important factor in elderly persons' health. Various studies have shown that medication non-adherence is associated with poor health status in this population. As part of a study of the effects of two interventions to promote medication adherence in patients treated for memory problems, information on medication adherence and cognitive status was collected at 3-month intervals. Twenty-seven participants (16 men, 11 women, age 71-92 years) were assigned to control or treatment conditions and adherence was evaluated with an electronic monitoring device. Cognitive status was evaluated at 3-month intervals beginning in April of 2003 and continuing through September of 2006. We have previously reported on the effectiveness of these interventions to promote adherence. In this paper, we examine the relations of cognitive status and adherence over time using a partial least squares path model in order to evaluate the extent to which adherence to cholinesterase medications was related to cognitive status. Adherence predicted cognitive status at later time points while cognition did not, in general, predict adherence. Results thus suggest that interventions to ensure high levels of medication adherence may be important for maintaining cognitive function in affected elderly people.