Sociodemographic and Clinical Characteristics Are Not Clinically Useful Predictors of Refill Adherence in Patients With Hypertension

Abstract

Background-Although many studies have identified patient characteristics or chronic diseases associated with medication adherence, the clinical utility of such predictors has rarely been assessed. We attempted to develop clinical prediction rules for adherence with antihypertensive medications in 2 healthcare delivery systems. Methods and Results-We performed retrospective cohort studies of hypertension registries in an inner-city healthcare delivery system (nϭ17 176) and a health maintenance organization (nϭ94 297) in Denver, Colo. Adherence was defined by acquisition of 80% or more of antihypertensive medications. A multivariable model in the inner-city system found that adherent patients (36.3% of the total) were more likely than nonadherent patients to be older, white, married, and acculturated in US society, to have diabetes or cerebrovascular disease, not to abuse alcohol or controlled substances, and to be prescribed fewer than 3 antihypertensive medications. Although statistically significant, all multivariate odds ratios were 1.7 or less, and the model did not accurately discriminate adherent from nonadherent patients (C statisticϭ0.606). In the health maintenance organization, where 72.1% of patients were adherent, significant but weak associations existed between adherence and older age, white race, the lack of alcohol abuse, and fewer antihypertensive medications. The multivariate model again failed to accurately discriminate adherent from nonadherent individuals (C statisticϭ0.576). Conclusions-Although certain sociodemographic characteristics or clinical diagnoses are statistically associated with adherence to refills of antihypertensive medications, a combination of these characteristics is not sufficiently accurate to allow clinicians to predict whether their patients will be adherent with treatment. (Circ Cardiovasc Qual Outcomes. 2009;2:451-457.)

Long‐term oral mesalazine adherence and the risk of disease flare in ulcerative colitis: nationwide 10‐year retrospective cohort from the veterans affairs healthcare system

“…Furthermore, all included patients had a combination of ICD-9 codes for UC and a minimum of two fills of mesalazine. This increased the captured diagnosis specificity as shown in previous work in other chronic diseases as hypertension 18,41 and chronic obstructive pulmonary disease. 42 Lastly, we were able to capture the high-dose steroid filling, but we cannot ensure that the intention for the prescribed drug was for acute exacerbation of UC.…”

“…It has been used widely to investigate medication use in chronic diseases, and most recently it has been applied in inflammatory bowel disease population. 4,17,18 The cohort was classified into three groups based on their MPR value: high adherers ( ! 80%), medium adherers (50% to <80%) and low adherers (<50%).…”

Characteristics of Patients with Primary Non-adherence to Medications for Hypertension, Diabetes, and Lipid Disorders

“…Further, the utilization, benefits, insurance, and prescriber characteristics in our models added little, as there was little difference between the c-statistics of full models and models containing only patient variables. Adherence is a complex behavior involving individual beliefs and psychosocial influences, 30,34 and whether factors that motivate patients to initiate medication are the same as factors that result in ongoing adherence is unknown. Steiner and Chan and colleagues noted in their discussions of adherence after therapy initiation that determinants of behavior are more complex than the information available from administrative datasets.…”

Patient Characteristics Associated with Medication Adherence

“…While the literature has reported some evidence of variation of adherence by age, race, co-morbidity status, and socioeconomic status (SES) (higher adherence in those older, white, lower co-morbidity, and higher SES), 8,9,[13][14][15][16][17] the majority of studies conducted have examined adherence within a given disease state. Few have examined adherence across multiple conditions to determine whether associations between adherence and patient characteristics are consistent.…”