Preliminary development of the Medication Nonpersistence Scale.

OBJECTIVES: To develop the Medication Nonpersistence Scale (MNPS)-a multi-item self-reported scale to measure medication persistence. SETTING: Six hundred seventy-five patients patronizing 3 separate independent community pharmacies in the southeastern United States participated in this research. PRACTICE INNOVATION: The MNPS, a self-reported measure, developed to provide an estimate of, and reasons for, medication nonpersistence. EVALUATION: Cross-sectional survey data were linked with retrospective prescription fill data obtained from 3 independent community pharmacies in the southeastern United States. The MNPS factor structure was studied by means of confirmatory factor analysis (CFA), and its scale reliability and convergent validity were evaluated with the use of the results of this analysis. Its concurrent validity was tested against a standardized days-to-discontinuation measure calculated over the past 12 months, and an attempt was made to arrive at an optimum cutoff point to identify patients who have been nonpersistent with their medications. RESULTS: The survey yielded 675 usable patients. The CFA confirmed a single-factor solution with good model fit (root mean square error of approximation = 0.06 [90% CI 0.05-0.07]; comparative fit index = 0.96). Moderate to strong evidence of scale reliability (Cronbach alpha = 0.75; construct reliability = 0.94; index of composite reliability developed for binary items = 0.91), convergent validity (standardized factor loadings >0.5 and statistically significant), and concurrent validity (unstandardized regression coefficient = -3.97; P = 0.03) was observed. Individuals who score 1 or higher on the MNPS were considered to be nonpersistent. CONCLUSION: The MNPS demonstrated good psychometric properties and offers a useful first step toward the self-reported measurement of medication persistence in clinical practice and research.

High-risk diabetic patients in Medicare Part D programs: are they getting the recommended ACEI/ARB therapy?

BACKGROUND: Diabetes patients with hypertension and/or renal disease are at an increased risk of cardiovascular morbidity and mortality. Clinical evidence suggests that the use of ACEI/ARB for these patients improves patient outcomes. OBJECTIVE: To describe ACEI/ARB utilization among high-risk patients with diabetes and to identify patient characteristics that predict suboptimal utilization of ACEI/ARB. DESIGN: A retrospective cohort study. PATIENTS: Diabetic patients with coexisting hypertension and/or renal disease with continuous Medicare coverage from October 1, 2005 through June 30, 2006 in six states (Alabama, California, Florida, Mississippi, New York, and Ohio). INTERVENTIONS AND MEASUREMENTS: Any ACEI/ARB use during the first 6 months of 2006. RESULTS: A total of 1,250,466 Medicare Part D enrollees met our inclusion criteria. ACEI/ARB utilization rates were 63%, 58.3%, and 43.1% among diabetic patients with hypertension and renal disease, hypertension without renal disease, and renal involvement without hypertension, respectively. After adjusting for all other characteristics studied, patients in the hypertension only (OR 0.83; 95% CI: 0.82-0.84) and renal disease only (OR: 0.48; 95% CI: 0.46-0.50) risk groups were less likely to use ACEI/ARB compared to diabetes patients with both hypertension and renal disease. Several demographics, including male gender, age older than 65, and white race, were all predictors of suboptimal ACEI/ARB use. Results from state-specific analyses are consistent with those for all six states. CONCLUSION: In this cohort, less than 60% of high-risk patients with diabetes were receiving the recommended ACEI/ARB therapy. Several patient demographic and clinical characteristics are strongly associated with suboptimal ACEI/ARB use.

Nonadherence to angiotensin-converting enzyme inhibitors and/or angiotensin II receptor blockers among high-risk patients with diabetes in Medicare Part D programs.

OBJECTIVES: To identify predictors of nonadherence to angiotensin-converting enzyme inhibitors (ACEIs) and/or angiotensin II receptor blockers (ARBs) and to assess the association between nonadherence to ACEIs/ARBs and potentially avoidable hospitalizations (PAHs) among elderly high-risk patients with diabetes. METHODS: Medicare Part D enrollees from six states who had diabetes and coexisting hypertension and/or renal disease, were aged 65 years or older, and who had filled at least one prescription for ACEIs/ARBs in the first 6 months of 2006 were included in this retrospective cohort study. The primary outcomes of interests were patient nonadherence to ACEI/ARB therapy, which was defined as a proportion of days covered (PDC) less than 0.8 and PAH for diabetes during the patient follow-up period (July 1, 2006, to March 31, 2007). RESULTS: A total of 599,141 patients (mean [+/-SD] age 75.6 +/-7.3 years, 66% women, 63% white, 15% black, and 9% Hispanic) were included. Among them, 46% were nonadherent to ACEI/ARB therapy and 6.3% had a PAH during the follow-up period. In multivariate logistic regressions, patients with diabetes and both hypertension and renal disease and patients with diabetes and renal disease only were 24% and 15% more likely, respectively, to be nonadherent to ACEI/ARB therapy compared with patients with diabetes and hypertension. Black and Hispanic patients were also more likely to be nonadherent to ACEI/ARB therapy. Nonadherence to ACEI/ARB therapy was associated with a 5% increase in the likelihood of PAH. CONCLUSION: Adherence to ACEI/ARB therapy is suboptimal among elderly high-risk patients with diabetes enrolled in Medicare Part D programs from six states, and nonadherence to ACEIs/ARBs is associated with a slightly increased risk for PAH.

Development of the medication adherence estimation and differentiation scale (MEDS).

OBJECTIVES: To develop a self-reported measure for medication adherence and compare its ability to predict the proportion of days covered (PDC) with contemporary scales. METHODS: Retrospective prescription fill data from three community pharmacies in the Southeastern US were assessed to identify patients that were 18 years of age or older, and had received at least one medication for diabetes, hypertension, or dyslipidemia. A cross-sectional survey containing the Medication adherence Estimation and Differentiation Scale (MEDS) was administered among these pharmacy patrons. The MEDS assessed the extent and reasons for non-adherence. Survey responses were anonymously linked with retrospective prescription fill data. A total of 685 patients were sampled. The proportion of days covered (PDC) was used as the criterion measure. The Morisky, Green, and Levine Adherence Scale (1986 Morisky scale) and the Medication Adherence Reasons Scale (MAR-Scale) were used as comparators. RESULTS: The MEDS presented a five-factor solution-worries about side-effects, worries about addiction, worries about cost, lack of perceived need, and unintentional non-adherence (CFI = 0.97; RMSEA = 0.06; SRMR = 0.03; standardized factor loadings greater than 0.5, and statistically significant). The relationship between MEDS scores and PDC was statistically significant (unstandardized regression coefficient = -0.50, p < .01). The MEDS performed better than the 1986 Morisky scale (R2 = 0.02 vs 0.05, standardized regression coefficient = -0.13 vs -0.21) and the MAR-Scale (R2 = 0.02 vs 0.05, standardized regression coefficient = -0.12 vs -0.21) in predicting PDC. CONCLUSIONS: The MEDS demonstrated good psychometric properties and performed better than the comparator scales in the prediction of PDC.

Isoflavone, glyphosate, and aminomethylphosphonic acid levels in seeds of glyphosate-treated, glyphosate-resistant soybean.

The estrogenic isoflavones of soybeans and their glycosides are products of the shikimate pathway, the target pathway of glyphosate. This study tested the hypothesis that nonphytotoxic levels of glyphosate and other herbicides known to affect phenolic compound biosynthesis might influence levels of these nutraceutical compounds in glyphosate-resistant soybeans. The effects of glyphosate and other herbicides were determined on estrogenic isoflavones and shikimate in glyphosate-resistant soybeans from identical experiments conducted on different cultivars in Mississippi and Missouri. Four commonly used herbicide treatments were compared to a hand-weeded control. The herbicide treatments were (1) glyphosate at 1260 g/ha at 3 weeks after planting (WAP), followed by glyphosate at 840 g/ha at 6 WAP; (2) sulfentrazone at 168 g/ha plus chlorimuron at 34 g/ha applied preemergence (PRE), followed by glyphosate at 1260 g/ha at 6 WAP; (3) sulfentrazone at 168 g/ha plus chlorimuron at 34 g/ha applied PRE, followed by glyphosate at 1260 g/ha at full bloom; and (4) sulfentrazone at 168 g/ha plus chlorimuron at 34 g/ha applied PRE, followed by acifluorfen at 280 g/ha plus bentazon at 560 g/ha plus clethodim at 140 g/ha at 6 WAP. Soybeans were harvested at maturity, and seeds were analyzed for daidzein, daidzin, genistein, genistin, glycitin, glycitein, shikimate, glyphosate, and the glyphosate degradation product, aminomethylphosphonic acid (AMPA). There were no remarkable effects of any treatment on the contents of any of the biosynthetic compounds in soybean seed from either test site, indicating that early and later season applications of glyphosate have no effects on phytoestrogen levels in glyphosate-resistant soybeans. Glyphosate and AMPA residues were higher in seeds from treatment 3 than from the other two treatments in which glyphosate was used earlier. Intermediate levels were found in treatments 1 and 2. Low levels of glyphosate and AMPA were found in treatment 4 and a hand-weeded control, apparently due to herbicide drift.

Medication adherence among recipients with chronic diseases enrolled in a state Medicaid program.

Limited information is currently available about medication adherence for common chronic conditions among the Medicaid population. The primary objective of this study was to assess medication adherence among Medicaid recipients with depression, diabetes, epilepsy, hypercholesterolemia, and hypertension. Factors influencing adherence were determined. The authors also assessed whether adherence influences the utilization of acute care services. The target population included nonelderly adult recipients (ages 21-64 years) who were continuously enrolled in the Mississippi (MS) Medicaid fee-for-service program from January 1, 2006 to December 31, 2007. Recipients were identified who had a medical services claim with a diagnosis of depression, diabetes, epilepsy, hypercholesterolemia, or hypertension in calendar year 2006. Within each chronic disease sample, medication adherence was determined using calendar year 2007 data for recipients who met inclusion and exclusion criteria. Recipients with adherence ≥80% were classified as adherent. Logistic regression analyses were used to determine the factors that predict medication adherence and the effect of adherence on concurrent all-cause acute care service (ie, hospitalization, emergency room visit) utilization. Approximately 24% of recipients with depression, 35.9% with diabetes, 53.6% with epilepsy, 32% with hypercholesterolemia, and 42.2% with hypertension were adherent. Within each chronic disease sample, males and whites had higher adherence than females and blacks. After controlling for demographic and disease-related covariates, recipients who were adherent had lower concurrent acute care service utilization than nonadherent recipients. Given the inverse relationship between adherence and acute care service utilization, policy makers should consider implementing educational interventions aimed at improving adherence in this underprivileged population.

Predictors of medication nonadherence among patients with diabetes in Medicare Part D programs: a retrospective cohort study.

OBJECTIVES: This study examined the prevalence of nonadherence with oral hypoglycemic agents, antihypertensive drugs (angiotensin-converting enzyme inhibitors [ACEIs] and angiotensin II receptor blockers [ARBs]), and statin medications among Medicare Part D enrollees with diabetes and analyzed the potential demographic and clinical factors that predict medication nonadherence. METHODS: This was a retrospective cohort study of Medicare Part D enrollees with diabetes from 6 states (Alabama, California, Florida, Mississippi, New York, and Ohio). Adherence was calculated as the proportion of days covered (PDC; number of days with medication on hand/number of days in the specified time interval). A PDC was derived for each of the 3 categories of medications for patients who had at least 1 claim for the same class of medication. A comorbidity measure was created for each beneficiary using the Deyo-adapted Charlson Comorbidity Index (CCI). Associations between nonadherence and patient characteristics including age, sex, race/ethnicity, and Deyo-adapted CCI were examined. Logistic regression models were constructed to identify predictors of nonadherence. RESULTS: The study included 1,888,682 patients with diabetes. The mean (SD) age was 71.6 (11.6) years, and 59.5% (1,123,220/1,888,682) were female. A total of 66.4% (1,254,538/1,888,682) were white, 16.3% (308,158/1,888,682) were black, and 7.8% (147,498/1,888,682) were Hispanic. Estimated rates of non-adherence for oral hypoglycemic agents, ACEIs/ARBs, and statins were 35.1% (386,666/1,101,533), 41.8% (449,561/1,075,285), and 46.4% (447,106/962,877), respectively. In unadjusted analyses, patients aged <65 years, women, black or Hispanic patients, and patients with higher Deyo-adapted CCI were more likely to be nonadherent to all 3 classes of medications. The results were consistent in multivariate analyses, and all results were statistically significant at P < 0.001. CONCLUSIONS: In this study of Medicare Part D enrollees with diabetes, patients aged <65 years, women, black or Hispanic patients, and those with higher comorbidity scores were more likely to be nonadherent to medications. Interventions should be developed to improve medication adherence among these subgroups so that patients can achieve the full benefits of prescribed pharmacologic therapies.