Heavy-tailed fractional Pearson diffusions

We define heavy-tailed fractional reciprocal gamma and Fisher-Snedecor diffusions by a nonMarkovian time change in the corresponding Pearson diffusions. Pearson diffusions are governed by the backward Kolmogorov equations with space-varying polynomial coefficients and are widely used in applications. The corresponding fractional reciprocal gamma and Fisher-Snedecor diffusions are governed by the fractional backward Kolmogorov equations and have heavy-tailed marginal distributions in the steady state. We derive the explicit expressions for the transition densities of the fractional reciprocal gamma and Fisher-Snedecor diffusions and strong solutions of the associated Cauchy problems for the fractional backward Kolmogorov equation

Ehrenfest-Brillouin-type correlated continuous time random walk and fractional Jacobi diffusion

Continuous time random walks (CTRWs) have random waiting times between particle jumps. Based on Ehrenfest-Brillouin-type model motivated by economics, we define the correlated CTRW that converge to the fractional Jacobi diffusion Y (E(t)), t ≥ 0, defined as a time change of Jacobi diffusion process Y (t) to the inverse E(t) of the standard stable subordinator. In the CTRW considered in this paper, the jumps are correlated so that in the limit the outer process Y (t) is not a L´evy process but a diffusion process with non-independent increments. The waiting times between jumps are selected from the domain of attraction of a stable law, so that the correlated CTRWs with these waiting times converge to Y (E(t))

Effects of depressive symptomatology on cancer‐related symptoms during oral oncolytic treatment

ObjectiveThis manuscript assesses association between depressive symptoms and symptoms from cancer and its treatment during the first 12 weeks of a new oral oncolytic treatment.MethodsThis secondary analysis used data from a recently completed trial of an intervention to improve adherence to oral oncolytic treatment and manage symptoms. Following the initiation of the new oral oncolytic medication, 272 patients were interviewed at intake and weeks 4, 8, and 12 to assess depressive symptoms, and symptoms from cancer and its treatment. Depressive symptoms were measured using the Center for Epidemiologic Studies‐Depression (CES‐D20). The summed index of 18 cancer‐related and treatment‐related symptoms as well as the number of symptoms above threshold at intake, weeks 4, 8, and 12 were related to intake and time‐varying CES‐D20 using linear mixed effects models.ResultsDepressive symptomatology was a significant predictor of cancer‐related and treatment‐related symptoms at all‐time points, but the strength of this relationship was greatest at the time of oral oncolytic agent initiation and at week 4. The strength of this relationship was the same for both summed symptom severity index and the number of symptoms above threshold, and using either intake or time‐varying CES‐D20.ConclusionIntroducing strategies to treat and manage symptoms of depression along with other symptoms might have added benefits among patients who start a new oral oncolytic treatment and report modest to higher levels of depressive symptoms. Assessments for the impact of strategies to lower depressive symptoms can be taken within the first 4 weeks.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147865/1/pon4916.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147865/2/pon4916_am.pd

An Intervention to Improve Adherence and Management of Symptoms for Patients Prescribed Oral Chemotherapy Agents: An Exploratory Study

Background: The use of oral chemotherapy agents to treat cancer has increased. Patients are responsible for adhering to complex dosing regimens, while monitoring and managing symptoms from side effects of the chemotherapy at home. Objective: This study examined an intervention to manage symptoms and promote adherence to oral chemotherapy agents. Intervention and Methods: A 3 group exploratory pilot study determined how an Automated Voice Response (AVR) system alone (N=40), or the AVR with strategies to manage symptoms and adherence (N=40), or the AVR with strategies to manage adherence (N=39) reduced symptom severity and improved adherence. Participants received a Symptom Management Toolkit, completed a baseline interview, and were randomized to receive 8 weekly AVR calls. The AVR directed patients to the toolkit for high symptoms and nurse calls occurred for management of severe symptoms or non-adherence. An exit interview occurred at 10 weeks. Results: Mean age was 59.6, with 70% female and 76% Caucasian. Overall, 42% of patients were non-adherent, with missed doses increasing with regimen complexity. Symptom severity declined over time in all groups. No difference was found in adherence rates among intervention groups. Higher adherence rates were related with lower levels of symptom severity across groups. Conclusions: Adherence is a significant clinical problem, which can affect efficacy of the cancer treatment. The AVR intervention alone was just as effective as the AVR plus the nurse intervention at promoting adherence and managing symptoms from side effects. Implications for Practice: Nurses need to focus on patient education by assuring patient understanding of oral agent regimen, and the need to adhere to the oral agent for efficacious cancer treatment. Nurses can promote the use of medication reminders and self- management of symptoms from side effects, to support adherence to the oral agent

Approximation of heavy-tailed fractional Pearson diffusions in Skorokhod topology

Continuous time random walks (CTRWs) have random waiting times between particle jumps. We establish fractional diffusion approximation via correlated CTRWs. Instead of a random walk modeling particle jumps in the classical CTRW model, we use discrete-time Markov chain with correlated steps. The waiting times are selected from the domain of attraction of a stable law

Do treatment patterns alter beliefs cancer patients hold regarding oral oncolytic agents?

ObjectiveCancer patients, particularly those prescribed with oral oncolytic medications, face treatment side effects and temporary and permanent stoppages of treatment. This research examines how events during treatment affect patients’ beliefs regarding oral oncolytic medications.MethodsA total of 272 cancer patients initiating 1 of 28 oral oncolytic agents were followed for 12 weeks. Assessments of Beliefs About Medications Questionnaire, symptoms, physical function, and depression measures were performed during telephone interviews at intake (medication start) and 4, 8, and 12 weeks. Electronic medical record audits identified dates of temporary and permanent medication stoppages. Linear mixed‐effects models were used for longitudinal analyses of the Beliefs About Medications Questionnaire scores in relation to patient characteristics, symptom severity, and medication stoppages.ResultsOver the initial 12 weeks, beliefs about the necessity of oral medications have increased, concerns have decreased, and interference of medications with daily lives has increased. Permanent stoppage of a medication predicted significant declines in beliefs about its necessity over time. Male patients, those less educated, those reporting higher symptom severity, and those experiencing temporary stoppages had greater concerns. Interference of medications with daily life was higher for males, increased with higher symptom severity, and differed by drug category.ConclusionsPatients’ beliefs in the necessity of their oral medication were affected only by a permanent drug stoppage. Symptom severity, education, and patient sex affected patients’ beliefs about their concerns with their medications and the interference medications posed for their daily lives. Interventions may need to target the distinct dimensions of beliefs during treatment with oral oncolytic agents.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142470/1/pon4606.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142470/2/pon4606_am.pd

Using technology to deliver cancer follow-up : a systematic review

Peer reviewedPublisher PD

Testing the Differential Effects of Symptom Management Interventions in Cancer

Objective: The purpose of this study was to test for moderating effects of patient characteristics on self-management interventions developed to address symptoms during cancer treatment. Patient’s age, education and depressive symptomatology were considered as potential moderators. Methods: A secondary analysis of data of 782 patients from two randomized clinical trials was performed. Both trials enrolled patients with solid tumors undergoing chemotherapy. After completing baseline interviews, patients were randomized to a nurse-delivered intervention versus intervention delivered by a “coach” in trial I, and to a nurse-delivered intervention versus an intervention delivered by an automated voice response system in trial II. In each of the two trials, following a 6-contact 8-week intervention, patients were interviewed at week 10 to assess the primary outcome of symptom severity. Results: While nurse-delivered intervention proved no better than the “coach” or automated system in lowering symptom severity, important differences in the intervention by age were found in both trials. Patients“coach” or automated system; while those \u3e75 years favored the nurse. Education and depressive symptomatology did not modify the intervention effects in either of the two trials. Depressive symptomatology had a significant main effect on symptom severity at week 10 in both trials (p=.03 and p Conclusions: Clinicians need to carefully consider the age of the population when using or testing interventions to manage symptoms among cancer patients

Proof of Concept of a Mobile Health Short Message Service Text Message Intervention That Promotes Adherence to Oral Anticancer Agent Medications: A Randomized Controlled Trial

Introduction: This multisite, randomized controlled trial assigned 75 adult cancer patients prescribed an oral anticancer agent to either an experimental group that received daily text messages for adherence for 21 days plus usual care or a control group that received usual care. Materials and Methods: Measures were administered at baseline, weekly (Weeks 1–8), and at exit (Week 9). A satisfaction survey was conducted following the intervention. Acceptability, feasibility, and satisfaction were examined. Primary outcomes were adherence and symptoms. Secondary outcomes were depressive symptoms, self-efficacy, cognition, physical function, and social support. Mixed or general linear models were used for the analyses comparing trial groups. Effect sizes (ES) were estimated to gauge clinical significance. Results: Regarding acceptability, 57.2% (83 of 145) of eligible patients consented, 88% (n = 37 of 42) receiving text messages read them most or all of the time, and 90% (n  = 38) were satisfied. The differences between experimental and control groups\u27 ES were 0.29 for adherence, 0.21 for symptom severity, and 0.21 for symptom interference, and differences were not statistically significant. Furthermore, perceived social support was higher (p = 0.04; ES = 0.54) in the experimental group. Conclusions: Proof of concept and preliminary efficacy of a mobile health intervention using text messages to promote adherence for patients prescribed oral anticancer agents were demonstrated. Patients accepted and had high satisfaction with the intervention, and adherence improved after the intervention. Text messages show promise. Additional research is needed prior to use in practice

A Randomized Controlled Trial of the Feasibility and Preliminary Efficacy of a Texting Intervention on Medication Adherence in Adults Prescribed Oral Anti-Cancer Agents: Study Protocol

Aim: The aim of this study was to report a study protocol that examines feasibility, preliminary efficacy and satisfaction of a text message intervention on the outcome of medication adherence in adult patients prescribed oral anti-cancer agents. Background: Administration of oral anti-cancer agents occurs in the home setting, requiring patients to self-manage the regimen as prescribed. However, many barriers to medication adherence exist: regimens are often complex, with cycling of two or more medications; side effects of treatment; most cancer patients are older with comorbid conditions and competing demands; and cognitive decline and forgetfulness may occur. Research indicates patients miss nearly one-third of the prescribed oral anti-cancer agent dosages. Text message interventions have been shown to improve medication adherence in chronic conditions other than cancer. However, a majority of those patients were less than 50 years of age and most cancer patients are diagnosed later in life. Design: A two-group randomized controlled trial with repeated measures. Methods: Seventy-five adult patients newly prescribed an oral anti-cancer agent will be recruited (project funded in April 2013) from community cancer centres and a specialty pharmacy. Participants will be randomized to either a control group (n = 25; usual care) or an intervention group (n = 50; usual care plus text messages timed to medication regimen). Outcome measures include: medication adherence, feasibility and satisfaction with the intervention. Data will be collected over 8 weeks: baseline, weekly and exit. Discussion: Standardized text message intervention protocol and detailed study procedures have been developed in this study to improve medication adherence