Effect of Cost-Related Medication Non-adherence Among Older Adults With Medication Therapy Management

Up to 32% of older patients take less medication than prescribed to avoid costs, yet a comprehensive assessment of risk factors for cost-related nonadherence (CRN) is not available. This review examined the empirical literature to identify patient-, medication-, and provider-level factors that influence the relationship between medication adherence and medication costs. We conducted searches of four databases (MEDLINE, CINAHL, Sciences Citations Index Expanded, and EconLit) from 2001 to 2006 for English-language original studies. Articles were selected if the study included an explicit measure of CRN and reported results on covarying characteristics. We found 19 studies with empirical support for concluding that certain patients may be susceptible to CRN: research has established consistent links between medication nonadherence due to costs and financial burden, but also to symptoms of depression and heavy disease burden. Only a handful of studies with limited statistical methods provided evidence on whether patients understand the health risks of CRN or to what extent clinicians influence patients to keep taking medications when faced with cost pressures. No relationship emerged between CRN and polypharmacy. Efforts to reduce cost-related medication nonadherence would benefit from greater study of factors besides the presence of prescription drug coverage. Older patients with chronic diseases and mood disorders are at-risk for CRN even if enrolled in Medicare's new drug benefit.

Previous studies found that medication errors result from lack of sufficient information during the prescribing step. Therefore, it is proposed that having a pharmacist available when patients are evaluated during the rounding process may reduce the likelihood of preventable adverse drug events (ADEs). The objectives of this study were to evaluate the impact of having a pharmacist participate with a physician rounding team on preventable ADEs in general medicine units and to document pharmacist interventions made during the rounding process. A single-blind, standard care-controlled study design was used to compare patients receiving care from a rounding team including a pharmacist with patients receiving standard care (no pharmacist on rounding team). Patients admitted to and discharged from the same general medicine unit were included in the study. The main outcome measure of this study was preventable ADEs. Patient records were randomly selected and evaluated by a blinded process involving independent senior pharmacist specialists and a senior staff physician. Interventions made by the pharmacists in the treatment group were documented. The rate of preventable ADEs was reduced by 78%, from 26.5 per 1000 hospital days to 5.7 per 1000 hospital days. There were 150 documented interventions recommended during the rounding process, 147 of which were accepted by the team. The most common interventions were (1) dosing-related changes and (2) recommendations to add a drug to therapy. Pharmacist participation with the medical rounding team on a general medicine unit contributes to a significant reduction in preventable ADEs.

The study aimed to synthesise qualitative studies of lay experiences of medicine taking. Most studies focused on the experience of those not taking their medicine as prescribed, with few considering those who reject their medicines or accept them uncritically. Most were concerned with medicines for chronic illnesses. The synthesis revealed widespread caution about taking medicines and highlighted the lay practice of testing medicines, mainly for adverse effects. Some concerns about medicines cannot be resolved by lay evaluation, however, including worries about dependence, tolerance and addiction, the potential harm from taking medicines on a long-term basis and the possibility of medicines masking other symptoms. Additionally, in some cases medicines had a significant impact on identity, presenting problems of disclosure and stigma. People were found to accept their medicines either passively or actively, or to reject them. Some were coerced into taking medicines. Active accepters might modify their regimens by taking medicines symptomatically or strategically, or by adjusting doses to minimise unwanted consequences, or to make the regimen more acceptable. Many modifications appeared to reflect a desire to minimise the intake of medicines and this was echoed in some peoples' use of non-pharmacological treatments to either supplant or supplement their medicines. Few discussed regimen changes with their doctors. We conclude that the main reason why people do not take their medicines as prescribed is not because of failings in patients, doctors or systems, but because of concerns about the medicines themselves. On the whole, the findings point to considerable reluctance to take medicine and a preference to take as little as possible. We argue that peoples' resistance to medicine taking needs to be recognised and that the focus should be on developing ways of making medicines safe, as well as identifying and evaluating the treatments that people often choose in preference to medicines.