Showing papers by "Philip S. Wang published in 2002"

Adherence to Therapy With Oral Antineoplastic Agents

Abstract: With the rise in availability and increasing use of oral anticancer agents, concerns about adherence to prescribed regimens will become an increasingly important issue in oncology. Few published studies have focused on adherence to oral antineoplastic therapy, in part because the vast majority of chemotherapy is delivered intravenously in physicians' offices or hospitals. In this article, we review current knowledge of adherence behavior with regard to oral medications in general, including factors associated with adherence and methods for measuring adherence. We also review published studies of adherence to oral antineoplastic agents in adult and pediatric populations and adherence issues in cancer prevention. The available evidence reveals that patient adherence to oral chemotherapy recommendations is variable and not easily predicted. Adherence rates ranging from less than 20% to 100% have been reported, and certain populations, such as adolescents, pose particular challenges. Future efforts should focus on improving measurement and prediction of adherence and on developing interventions to improve adherence for both patients in clinical trials and patients being treated outside of the research setting. Assessment of adherence among individuals with cancer and implementation of interventions in situations of poor adherence should improve clinical outcomes.

Adequacy of treatment for serious mental illness in the United States.

Abstract: Objectives. The purpose of this study was to assess the prevalence and correlates of treatment for serious mental illness. Methods. Data were derived from the National Comorbidity Survey, a cross-sectional, nationally representative household survey assessing the presence and correlates of mental disorders and treatments. Crude and adjusted likelihoods of receiving treatment for serious mental illness in the previous 12 months were calculated. Results. Forty percent of respondents with serious mental illness had received treatment in the previous year. Of those receiving treatment, 38.9% received care that could be considered at least minimally adequate, resulting in 15.3% of all respondents with serious mental illness receiving minimally adequate treatment. Predictors of not receiving minimally adequate treatment included being a young adult or an African American, residing in the South, being diagnosed as having a psychotic disorder, and being treated in the general medical sector. Conclusions. Inadequa...

Dropping out of mental health treatment: Patterns and predictors among epidemiological survey respondents in the United States and Ontario

Abstract: OBJECTIVE: The authors interviewed individuals treated for self-described mental health problems in the preceding year to examine patterns and predictors associated with dropping out of treatment METHOD: Subjects were drawn from respondents to community epidemiological surveys carried out in representative samples of the United States and Ontario populations Dropouts were those who had left mental health treatment during the prior year for reasons other than symptom improvement The surveys also assessed potential dropout correlates: sociodemographic characteristics, attitudes about mental health care, disorder type, provider type, and treatment received RESULTS: The proportion of dropouts did not significantly differ between the United States (192%) and Ontario (169%), nor did the effects of the predictors differ significantly between the two samples Sociodemographic characteristics associated with treatment dropout included low income, young age, and, in the United States, lacking insurance covera

Noncompliance with antihypertensive medications: the impact of depressive symptoms and psychosocial factors.

Abstract: Despite the availability of effective therapy, hypertension remains poorly controlled in the United States and other industrialized countries. In the Third National Health and Nutrition Examination Survey, nearly half of hypertensive patients in the community-based sample were found to be taking no prescription medication, and only one quarter of those who were being treated had their blood pressure adequately controlled.1 Patient noncompliance with prescribed treatments is a central reason for the failure to control hypertension in those receiving therapy.2 Numerous investigations have found that half of hypertensive patients do not comply adequately with treatment, and that half of those with “refractory” hypertension are in fact nonadherent.3–7 Such high levels of noncompliance are of tremendous concern, given the serious consequences of uncontrolled hypertension on cardiovascular, cerebrovascular, and renal morbidity as well as mortality.8 Clearly, interventions to improve adherence with antihypertensive medications are needed. However, if such interventions are to be successfully designed, targeted, and cost-effective, it is critical to understand the complex reasons for nonadherence, and to identify those that are modifiable.9 Investigators have identified some sociodemographic and clinical features associated with compliance (e.g., age, gender, race, education, employment, socioeconomic status, or the presence of specific comorbid conditions such as cardiovascular disease), although the findings are inconsistent. 2,3,10–16 Despite the likelihood that psychosocial and behavioral characteristics may be important determinants of compliance, few rigorous studies have defined the impact of these features on adherence; those that have been conducted have produced inconsistent results. The variable receiving the most attention has been patients' health beliefs, including their perceptions of the threat posed by the condition, the effectiveness of treatments, and the importance of complying with therapy.17–19 Other psychosocial variables thought to influence antihypertensive medication adherence include: knowledge of hypertension and its treatment14,20; social support21,22; satisfaction with health care10,23,24; and the locus of control (i.e., the degree to which a patient feels that control over their circumstances is internal or external).25 Behaviors that have been examined and related to compliance with blood pressure medication have included use of alcohol or substances2,26 and smoking.14 The effect of psychopathology on compliance with medications for other cardiovascular conditions has been considered, but rigorous study of such relationships has been limited.27 Unfortunately, few studies of the relationships between psychosocial factors and compliance with antihypertensives have been adequately powered, simultaneously adjusted for other determinants of compliance, or conducted in typical clinical populations; and few have used precise assessments of compliance. Therefore, in the current study, we employed typical outpatient populations and an objective measure of compliance to test the hypothesis that believing in the importance of treating hypertension, possessing greater knowledge, having more social support, being more satisfied, having a more external locus of control, responding in a more socially desirable manner, having fewer depressive symptoms, and consuming less alcohol or tobacco would all be associated with greater compliance with antihypertensive medications. Although our hypothesis was limited to the independent effects on compliance of these understudied psychosocial and behavioral variables, we also considered it essential to adjust for more established determinants including demographic, clinical, and health care utilization variables.

Dopamine Antagonists and the Development of Breast Cancer

Abstract: Background Although animal studies have raised the possibility that prolactin-elevating dopamine antagonists used to treat psychotic disorders may initiate and promote breast cancers, epidemiologic studies in humans have been limited and inconsistent. Methods A retrospective cohort study was conducted of 52 819 women exposed and 55 289 not exposed to dopamine antagonists between January 1, 1989, and June 30, 1995. All participants were 20 years or older, initially free of breast cancer, and enrolled in the Medicaid or the Pharmaceutical Assistance to the Aged and Disabled programs of New Jersey. Incident breast cancer cases were identified through the New Jersey Cancer Registry and definitive breast cancer surgeries. Adjusted hazard ratios of breast cancer were calculated from multivariable proportional hazards models. Results Use of antipsychotic dopamine antagonists was associated with a 16% increase in the risk of breast cancer (adjusted hazard ratio, 1.16; 95% confidence interval, 1.07-1.26), with a dose-response relationship between larger cumulative dosages and greater risk. The increased risk was also seen in women who used prolactin-elevating antiemetic dopamine antagonists despite having different breast cancer risk profiles than antipsychotic dopamine antagonist users. Dopamine antagonist use was not associated with risk of colon cancer, a control condition not related to elevated prolactin levels. The increased risk of breast cancer among dopamine antagonist users was not explained by increased surveillance or protopathic bias. Conclusions Antipsychotic dopamine antagonist use may confer a small but significant risk of breast cancer. In light of the small hazards and the possibility of residual confounding, these findings should lead to follow-up investigations but not to changes in treatment strategies.

Distinguishing generalized anxiety disorder from major depression: prevalence and impairment from current pure and comorbid disorders in the US and Ontario.

Abstract: Estimation of comparative disease burden in epidemiological surveys is complicated by the fact that high comorbidities exist among many chronic conditions. The easiest way to take comorbidity into consideration is to distinguish between pure and comorbid conditions and to evaluate the incremental effects of comorbid conditions in prediction equations. This approach is illustrated here in an analysis of the effects of pure and comorbid major depression (MD) and generalized anxiety disorder (GAD) on a number of different measures of role impairment in the US National Comorbidity Survey (NCS) and the Mental Health Supplement to the Ontario (Canada) Health Survey (the Supplement). Pure MD and pure GAD were found to have roughly equal independent associations with role impairments. The incremental effects of having comorbid MD and GAD were found to vary depending on the outcome under investigation. The paper closes with a discussion of the methodological complexities associated with generalizing to comorbidities that involve rare conditions or more than two disorders. Copyright © 2002 Whurr Publishers Ltd.

Clozapine use and risk of diabetes mellitus.

Abstract: Recent reports have raised the concern that clozapine increases the risk for diabetes mellitus. Accurate pharmacoepidemiologic data on whether such a hazard exists and its magnitude are needed to enable clinicians and patients to make proper treatment decisions about clozapine. The authors performed a case-control study involving 7,227 cases of newly treated diabetes and 6,780 controls, all with psychiatric disorders. Cases and controls were older than 20 years and enrolled in government-sponsored drug benefit programs in New Jersey. The authors measured the use of clozapine or other antipsychotic medications and additional covariates. They developed logistic regression models adjusted for demographic, clinical, and health care use characteristics to identify whether clozapine users were at increased risk to begin treatment for diabetes. Clozapine use was not significantly associated with developing diabetes (adjusted odds ratio [OR], 0.98; 95% confidence interval [CI], 0.74-1.31). There was no suggestion of relationships between larger dosages or longer durations of clozapine use and increasing risks of diabetes. On the other hand, nonclozapine antipsychotic medication use was associated with a modest but significantly increased risk of developing diabetes (adjusted OR, 1.13; 95% CI, 1.05-1.22). Among individual nonclozapine antipsychotics, significantly elevated risks were observed for two phenothiazine agents: chlorpromazine (adjusted OR, 1.31; 95% CI, 1.09-1.56) and perphenazine (adjusted OR, 1.34; 95% CI, 1.11- 1.62). In contrast to earlier reports, these results provide some reassurance that clozapine does not increase the risk of developing diabetes. Additional data from pharmacoepidemiologic studies and randomized controlled trials are needed to exclude the possibility of residual confounding and ensure the appropriate use of this agent.

Effects of Efforts to Increase Response Rates on a Workplace Chronic Condition Screening Survey

Abstract: Objective. Expanded health risk appraisal (HRA) surveys can help employers target chronic conditions for outreach or disease management interventions by providing data on the prevalences of conditions and their effects on work performance. However, concerns exist about the accuracy of this data because most HRAs have low response rates. We evaluated these concerns by examining the prevalences and work impairments associated with chronic conditions across four HRA subsamples that differed in intensity of recruitment effort. Methods. Two thousand five hundred thirty-nine working people were invited to complete an expanded HRA survey that included questions about chronic conditions, work impairments, and demographics. Condition prevalences and associations between conditions and work impairment were compared across subsamples who responded after a single mailing, after two mailings, and in a telephone interview after the mailings either with or without a $20 incentive. Results. Consistent with previous research, response rates varied dramatically across the four subsamples (from 20.1% with only one mailing to 67.7% with telephone administration and a financial incentive). However, the estimated prevalences of chronic conditions, levels of work impairment, and effects of chronic conditions on work impairment did not differ with intensity of recruitment effort. Conclusions. Expanded HRAs can provide useful data on the prevalences and work impairments associated with chronic conditions even if response rates are low. Confirmation of these results is required, however, in new samples. Additional research is also needed on innovative and cost-effective strategies to improve HRA response rates.

Urinary antispasmodic use and the risks of ventricular arrhythmia and sudden death in older patients.

Abstract: OBJECTIVES: The introduction of new medications to treat overactive bladder has resulted in a significant increase in the number of individuals with this condition who use medications for symptoms. Formal epidemiological studies of the safety of these medications in typical patient populations are lacking, particularly studies of serious events. We sought to determine whether the use of urinary antispasmodics increases the risk of ventricular arrhythmias or sudden death. DESIGN: Retrospective cohort study. SETTING: Retrospective analysis of data of participants in community, hospital or nursing home setting. PARTICIPANTS: Fourteen thousand six hundred thirty-eight subjects with a diagnosis of urinary incontinence made between January 1, 1991, and June 30, 1995; all were aged 65 and older and enrolled in Medicare and Medicaid or the Pharmacy Assistance for the Aged and Disabled programs of New Jersey. MEASUREMENTS: Filled prescriptions for oxybutynin (Ditropan), flavoxate (Urispas), hyoscyamine (Cystospas), and hyoscyamine sulfate (Cystospas-M) were used to define days of exposure to these drugs. We also identified all use of nonsedating antihistamines and cytochrome P450 3A4 inhibitors, and their concurrent use, to serve as a positive control exposure. Two outcomes were then defined: a new diagnosis of ventricular arrhythmia combined with initiation of an antiarrhythmic medication and sudden death. Other covariates, including clinical, demographic, medication use, and healthcare utilization variables, were also assessed. Adjusted risk ratios of ventricular arrhythmia and sudden death were derived from multivariable Cox proportional hazards models. RESULTS: There was no significant association between periods of use of urinary antispasmodics and the development of ventricular arrhythmias (adjusted risk ratio (RR) = 1.23, 95% confidence interval (CI) = 0.87-1.75) or sudden death (adjusted RR = 0.70, 95% CI = 0.28-1.74). A significantly increased risk of ventricular arrhythmia was observed for the positive control regimen, concurrent use of nonsedating antihistamines and cytochrome P450 3A4 inhibitors (adjusted RR = 5.47; 95% CI = 1.34-22.26), but not for use of either drug group alone. Concurrent use of nonsedating antihistamines and cytochrome P450 3A4 inhibitors was also associated with a significant increase in the risk of sudden death (adjusted RR = 21.50, 95% CI = 5.23-88.37). Other variables significantly associated with ventricular arrhythmia included ischemic heart disease and congestive heart failure, whereas nursing home use before the index date was associated with a decreased likelihood of receiving a diagnosis of and treatment for ventricular arrhythmia. Other variables significantly associated with sudden death included male gender, black race, and congestive heart failure. CONCLUSIONS: Antimuscarinic urinary antispasmodics available before 1996 were not associated with an increased risk of ventricular arrhythmias and sudden death. Additional study will be required to confirm these results, exclude the possibility of unmeasured confounders contributing to any lack of an observed relationship, and extend these findings to newer agents such as tolterodine.

REVIEW Adherence to Therapy With Oral Antineoplastic Agents

Abstract: With the rise in availability and increasing use of oral anticancer agents, concerns about adherence to prescribed regimens will become an increasingly important issue in oncology. Few published studies have focused on adherence to oral antineoplastic therapy, in part because the vast majority of chemotherapy is delivered intravenously in physicians’ offices or hospitals. In this article, we review current knowledge of adherence behavior with regard to oral medications in general, including factors associated with adherence and methods for measuring adherence. We also review published studies of adherence to oral antineoplastic agents in adult and pediatric populations and adherence issues in cancer prevention. The available evidence reveals that patient adherence to oral chemotherapy recommendations is variable and not easily predicted. Adherence rates ranging from less than 20% to 100% have been reported, and certain populations, such as adolescents, pose particular challenges. Future efforts should focus on improving measurement and prediction of adherence and on developing interventions to improve adherence for both patients in clinical trials and patients being treated outside of the research setting. Assessment of adherence among individuals with cancer and implementation of interventions in situations of poor adherence should improve clinical outcomes. [J Natl Cancer Inst 2002;94:652– 61]