HIV/AIDS is the most important infectious disease. The significant benefits of new antiretrovirals to HIV/AIDS patients have been documented but these benefits depend on strict patient adherence. Although various published articles have focused on patient non-adherence, most of them have failed to assess the economic and clinical impacts of non-adherence. Maryland Medicaid claims data were used to evaluate risk factors, economic impact and impact of non-adherence on opportunistic infections (OI). The study population included patients who were continuously enrolled in Maryland Medicaid program from the index date to July 30, 1997. The mean non-adherence rate was 20%. Caucasian, male and/or patients who resided in Baltimore County had a significantly lower non-adherence rate compared to their counterparts. In addition, patients treated with protease inhibitor (PI) had a significantly lower non-adherence rate than their counterparts. Race, gender, and resident of Baltimore County were not significantly associated with a ≥95% adherence rate. Age was positively and PI treatment was negatively associated with a ≥95% adherence rate. Results consistently indicate that patients with a ≥95% adherence rate had lower monthly HIV/AIDS-related costs than their counterparts. In addition, Caucasian patients and/or patients with Medicaid and Medicare coverage had a lower monthly cost than their counterparts. However drug dependents had a significantly higher monthly cost than their counterparts. Patients who died, patients with OI and/or patients with severe mental illness had a significantly higher monthly cost than their counterparts. The impact of a ≥95% adherence rate on OI was insignificant. However, the results should be interpreted with caution. Limited sample size and low prevalence of OIs raised the issue of lack of statistical power, which may impede detection of the impact. In conclusion, this study confirms that patient social and clinical factors are significantly associated with non-adherence in a Medicaid HIV/AIDS population. Most importantly, a ≥95% patient adherence rate is associated with a lower monthly cost. The impact of a ≥95% adherence rate on risks of having OI is insignificant which may be due to lack of statistical power. Future studies should assess the clinical impact on more prevalent OIs in a larger patient population.

Kidney transplant recipients (KTRs) have to take multiple daily medications, look for signs of acute rejection, have frequent blood draws and often manage additional chronic conditions. Appropriate management of the transplanted kidney is crucial to minimize the potential for graft failure and a return to the transplant wait list. There is a limited knowledge on underlying behavioral factors that may influence KTRs' adherence to self-care behaviors and the impact of adherence to self-care behaviors on the occurrence of patient safety events. This study aims to 1) Describe variations of self-efficacy based on individual KTRs'characteristics, 2) Explore the association between self-efficacy, health literacy and adherence to self-care behaviors and 3) Explore the association between adherence to self-care behaviors and patient safety events (diarrhea and hypoglycemia). Four hundred and thirty-five eligible KTRs received a survey inquiring about self-efficacy, health literacy, social support, medication adherence, self-care behaviors and patient safety events. Linear regression analyzed variations of self-efficacy in KTRs. Self-efficacy was tested as a mediator or as a moderator of health literacy on adherence to self-care behaviors. Logistic regression analyzed associations between adherence to self-care behaviors and patient safety events. One hundred and eighty-two KTRs completed the survey (42% participation rate). Mean age of responders was 59.5 (+/-12.1) years; 61.0% were male; and 38.1% were African American. The mean time since transplant was 38.0 (+/- 18.1) months. Being African American was associated with lower self-efficacy (β= -0.61, p=0.03) while an increase in functional health literacy was associated with an increase in self-efficacy (β=0.72, p<0.01). Self-efficacy was a partial mediator of functional and communicative health literacy on adherence to self-care behaviors (functional: αβ=0.32, CI: 0.11-0.60; communicative: αβ=0.37,CI: 0.11-0.71). There was no association between adherence to self-care behaviors and patient safety events. Clinicians need to monitor patients with low self-efficacy and low health literacy. Teach-back method and frequent communication can help increase self-efficacy. Use of larger font, photos and visual cues will help patients with limited health literacy. These methods may optimize KTRs' adherence to self-care behaviors.

Background. Low adherence rates to antihypertensive pharmacotherapy have been documented everywhere, especially among people of lower socioeconomic status such as Medicaid beneficiaries. Existing studies tend to focus on hypertensive patients who received mono-therapy or measure adherence at a fixed point in time, which may generate external validity issues or not be suitable for patients whose survival periods vary considerably. Purpose. To examine the relationship between patient adherence to antihypertensive medication and subsequent risk of cardiovascular events by using a new approach to measure adherence. Methods. A secondary data analysis of a mid-Atlantic Medicaid Managed Care Organization (MCO) data was conducted. We used Ordinary Least Squares (OLS) models and logistic regression models to examine predictors of patients' adherence at one year post index date. We also used Cox's Proportional Hazard models and pooled logistic regressions to investigate the relationship between adherence and subsequent risk of cardiovascular events. Adherence was first measured as a Cumulative Medication Acquisition (CMA) at six months post index date and second as CMA at each month since six months post index date until the date of disenrollment, date of a cardiovascular event, or the end of the study time frame, whichever comes first. We compared the area under Receiver Operating Characteristic (ROC) curves of the time-constant and time-varying approaches in terms of their utility in assessing risk of cardiovascular events. Results. A total of 3091 patients were included for the fist study aim, with an estimated mean annual CMA score of 0.649 (median = 0.652). For other study aims, 7939 patients met the inclusion criteria and 140 cardiovascular events were found after six months post index date. A higher CMA score was found to be protective against cardiovascular events, when controlling for potential confounders. For each 10% increase of CMA score, the hazard of cardiovascular events decreased by approximately 14% and the effect was significant (P = 0.0134). The model with CMA measured with time-varying approach also yielded by similar results and a Mann-Whitney test indicated there was no significant difference in terms of utilities of time-constant and time-varying approach in predicting risk of cardiovascular events. Conclusions. In this Medicaid population, patient adherence to antihypertensive medications is affected by sociodemographic factors and health status. Adherence at six months post index date is a significant predictor of subsequent risk of cardiovascular events. Adherence measured at a fixed point in time and by time varying method are similar in predicting cardiovascular health outcomes.

Few studies have been conducted that explore the impact of cardiovascular disease (CVD) hospitalizations on patient adherence to CVD drugs. Medicaid beneficiaries at high-risk for CVD, a vulnerable population, had not been a focus of prior studies in exploring the impact of patient adherence to cardioprotective drugs on health utilization. The study population was Maryland Medicaid beneficiaries with hypertension, hyperlipidemia, or diabetes. Adherence rates to antidiabetic (AD), antihypertensive (AH), or antihyperlipidemic (AL) drugs were measured in the 6-month pre-index and post-index periods. Patients with and without CVD hospitalization were matched on gender, race, age (±5 years), and pre-index adherence rate (±5%). Adherence rate to cardioprotective drugs among patients with a CVD event was measured in the 6-month, one-year, or two-year post-index periods. Patients with and without adherence to cardioprotective drugs were matched using propensity score matching. Conditional logistic regression analysis was conducted to explore the impact of CVD hospitalization on patient adherence to AD, AH, or AL drugs. The association of patient adherence to cardioprotective drugs with hospital utilization was explored using Cox regression analysis. Patients with CVD hospitalization were more likely than those without CVD hospitalization to be adherent to AD or AH drugs in the 6-month post-index period. Improved adherence to AD, AH, or AL drugs comparing the 6-month post-index to the 6-month pre-index period was more likely to be shown in patients with CVD hospitalization than in those without CVD hospitalization. A substantial proportion of patients were not adherent to AD, AH, or AL drugs during the 6-month post-CVD hospitalization period. Patients who were adherent to at least one cardioprotective drug were less likely than those who were not adherent to be associated with the risk of experiencing any all-cause hospitalizations, CVD-related hospitalizations, or CVD-related emergency room (ER) visits. Hospital-based education might provide an opportunity for patients to improve their awareness of the importance of medication adherence. Follow-up interviews by health professionals could help patients maintain adherence to medication after hospital discharge. Medicaid beneficiaries at high-risk for CVD are vulnerable, and improving adherence to cardioprotective drugs in this population might contribute to a reduction in hospital utilization.

Background: Coverage restrictions for antipsychotics are associated with access problems in Medicaid but their impact in Medicare Part D is unknown. The relationship between antipsychotic adherence, hospitalization risk, and treatment costs among Part D enrollees with serious mental illness also has not been systematically examined. Evaluating the association between adherence and outcomes is complicated by a recent policy change requiring the redaction of substance abuse claims from the Medicare research files, as hospitalizations and spending for beneficiaries with serious mental illness-many of whom have comorbid substance abuse disorders-may be systematically underreported. Methods: Enrollment, formulary, utilization, and spending data were obtained from the CMS Chronic Conditions Warehouse for 2011-2012. Effects of coverage restrictions on antipsychotic utilization were assessed by exploiting a unique natural experiment in which low-income beneficiaries were randomly assigned to prescription drug plans with varying levels of formulary generosity. The scope of the substance abuse claims redaction was determined by comparing unredacted beneficiary-level expenditure data to expenditures calculated from the redacted claims. Antipsychotic adherence was measured by the proportion of days covered (PDC) and stratified into four categories: PDC<0.70; 0.70≤PDC<0.80; 0.80≤PDC<0.90; and PDC≥0.90. Probit regressions and two-part generalized linear models were used to examine relationships between adherence in year one and hospitalizations and expenditures, respectively, in year two. Results: Despite considerable variation in the use of coverage restrictions across Part D plans, there was no evidence that restrictions significantly altered utilization patterns or reduced overall utilization of antipsychotics. Nearly one in five Part D enrollees with serious mental illness had claims affected by the redaction and average Part A spending among those with redacted claims was underreported by 57%. Based on analysis of the unredacted data, adherence to antipsychotic therapy was associated with significantly lower probability of psychiatric hospitalization and lower hospital expenditures. Conclusions: Coverage restrictions do not limit access to antipsychotics among Part D enrollees. Benefits of sustained adherence to antipsychotics for beneficiaries with serious mental illness include lower probability of psychiatric hospitalization and lower hospital spending. Researchers should exercise caution when using redacted Medicare claims to analyze utilization and spending outcomes for this population.

An important but understudied public health problem in HIV/AIDS research is disparities in highly active antiretroviral therapy (HAART) discontinuation among those with a comorbid serious mental illness (SMI). Despite evidence that Blacks are more likely to discontinue HAART than Whites, few studies have investigated disparities in HAART use and health outcomes among individuals with HIV/AIDS and a comorbid SMI. This study aimed to 1) assess the relationship of race and age on HAART discontinuation; 2) assess whether mental health visits mediate the relationship of race and age on HAART discontinuation; and 3) determine if HAART discontinuation is associated with hospitalizations for all-cause and immunocompromised conditions, and if this differs by race and age. HIV Research Network data from 2000-2010 were used for this study. The cohort was selected among individuals aged 18 or older, diagnosed with HIV/AIDS and a comorbid SMI, in care for HIV/AIDS, and initiated HAART between 2001-2007. The cohort was followed for four years to assess HAART discontinuity and treatment outcomes. Logistic regression was used to analyze the proposed relationships between race and age on HAART discontinuation, mental health visits, and hospitalizations for all-cause and immunocompromised conditions. HAART discontinuation was not statistically significantly different between Black and White individuals, but Hispanics had 32% lower odds than Whites of discontinuing HAART. Younger age was associated with a 28%-74% greater odds of HAART discontinuation compared to those aged 50 and older. Mental health visits did not differ significantly between Blacks and Whites, but Hispanics were more likely to have mental health visits than Whites. Ten or more mental health visits was a partial mediator between younger age and HAART discontinuation, with adults aged 18-29 and 30-39 years less likely to have 10 or more mental health visits and more likely to discontinue HAART. Compared to Whites, Blacks were more likely to be hospitalized in year four for all-cause and immunocompromised conditions. Individuals who discontinued HAART were less likely to have a year four all-cause hospitalization than those who continued HAART. This research deepens our understanding of disparities in HAART continuity and the impact on health outcomes for a vulnerable population.

Little is known about at-risk youth in terms of hypertension (HTN) treatment. This study explored the community-based prevalence of pediatric hypertension treatments among Medicaid-insured youth. We examined clinician-reported diagnoses (CR-DX) and racial/ethnic disparities in outpatient antihypertensive (AHT) medication use, days of persistence of AHT use, inpatient hospitalizations, and emergency department (ED) visits. A cross-sectional design was used for this study, employing retrospective data from personal summary, medical, pharmacy, and inpatient administrative claims files for youth continuously enrolled in 11 states Medicaid programs in the year 2003. Multivariate logistic regression adjusted for covariates measured prevalence of CR-DX of HTN, dispensed AHTs, hospitalizations, and ED visits; and Cox proportional-hazards regression was used to analyze persistence of AHT use by racial/ethnic group. A total of 7,795,395 youth, < 18 years of age, were eligible for this study. Analysis included 7,782 youth (0.10%) with ≥ 2 CR-DX of HTN. Primary HTN was 13 times more common than secondary HTN (80% vs. 6%). African American youth had the greatest likelihood of diagnosed HTN compared to Caucasian youth (OR=1.27, p<0.0001). Approximately 46% of youth diagnosed with HTN and 0.32% of youth without diagnosed HTN had dispensed AHTs. No racial/ethnic disparities in treatment were observed: African American youth (OR=1.06, p=0.43) and Hispanic youth (OR=0.96, p=0.59) were as likely as Caucasian youth to be treated with an AHT medication following diagnosis of HTN. Among youth with diagnosed primary HTN, persistence on AHT therapy did not differ among racial/ethnic groups. Older youth, aged 10 to 14 years (HR=1.40, p=0.025) and those aged 15 to 17 years (HR=1.45, p=0.011) had significantly shorter persistence with AHT therapy. Youth eligible for Supplemental Security Income (SSI), i.e. those with disabilities, had longer persistence on AHT therapy (HR=0.79; p=0.013) than those in other eligibility groups. African American and Hispanic youth with HTN were as likely as Caucasian youth to have a hospitalization or ED utilization at any time. The findings from this study highlight specific subpopulations (i.e. African American, disabled, and older youth) needs in HTN treatment that warrant further research, to assure optimal community-based care.

Study Objectives: To examine the prevalence of and factors associated with Antiparkinson drug (APD) use and adherence, and the association of APD use and adherence with healthcare utilization and expenditures in Medicare Part D enrollees with Parkinson's disease (PD). Methods: A retrospective observational study was conducted using the 2006-2007 Medicare Chronic Care Condition Warehouse data which represents a 5 percent sample of Medicare beneficiaries. The PD sample was selected with (1) at least 1 medical claim with an ICD-9 code 332.0 in two consecutive years; and (2) continuous enrollment in Medicare Parts A, B, and D from 6/1/2006 through 12/31/2007 or date of death. The total study interval was 579 days. APD use measures included any use, duration, and adherence (Medication Possession Ratio [MPR]). Factors associated with APD use measures were examined using modified-Poisson regressions with Generalized Estimating Equations. The association of APD use/adherence with utilization and expenditure outcomes was evaluated with negative binomial and gamma General Linear Models, respectively. Results: 12% of PD patients (n=8,758) did not use any APDs, and a fourth of APD users had a duration of therapy for 435 days or fewer and an MPR of less than 0.80. Patients with cognitive impairment and with 11 or more comorbidities were less likely to use APDs; and if using, they were less likely to possess APDs persistently and regularly. Other factors associated with not using APDs included low-income-subsidy eligibility and having no neurologist visits. Factors associated with poor adherence included older age (65 or older), non-white ethnicity, and having changes in APD therapy. Longer duration and higher adherence were associated with a reduced rate of all-cause utilization for acute (hospital and emergency room [ER]), chronic (Part A skilled nursing facility [SNF] and home health agency), and physician care (only for adherence). Similar patterns were found with PD-only and PD-related-comorbidities hospital, ER, and Part A SNF care. Also, significantly reduced total, Part A, and Part B, and increased Part D expenditures were observed in longer-duration users and in higher adherers. Conclusion: Significant reduction in healthcare utilization and expenditures could be achieved by improved duration of use and adherence to APDs.