Measuring comorbidity in cardiovascular research: a systematic review

Use of machine learning to predict medication adherence in individuals at risk for atherosclerotic cardiovascular disease

Background

Medication nonadherence is a critical problem with severe implications in individuals at risk for atherosclerotic cardiovascular disease. Many studies have attempted to predict medication adherence in this population, but few, if any, have been effective in prediction, sug-gesting that essential risk factors remain unidentified.

Objective

This study's objective was to (1) establish an accurate prediction model of medi-cation adherence in individuals at risk for atherosclerotic cardiovascular disease and (2) identify significant contributing factors to the predictive accuracy of medication adherence. In particular, we aimed to use only the baseline questionnaire data to assess medication adherence prediction feasibility.

Methods

A sample of 40 individuals at risk for atherosclerotic cardiovascular disease was recruited for an eight-week feasibility study. After collecting baseline data, we recorded data from a pillbox that sent events to a cloud-based server. Health measures and medication use events were analyzed using machine learning algorithms to identify variables that best predict medication adherence.

Results

Our adherence prediction model, based on only the ten most relevant variables, achieved an average error rate of 12.9%. Medication adherence was closely correlated with being encouraged to play an active role in their treatment, having confidence about what to do in an emergency, knowledge about their medications, and having a special person in their life.

Conclusions

Our results showed the significance of clinical and psychosocial factors for predicting medication adherence in people at risk for atherosclerotic cardiovascular diseases. Clini-cians and researchers can use these factors to stratify individuals to make evidence-based decisions to reduce the risks.

A pilot clinical trial of a self-management intervention in patients with a left ventricular assist device

Self-management is a health behavior known to predict treatment outcomes in patients with multiple co-morbidities and/or chronic conditions. However, the self-management process and outcomes in the left-ventricular assist device (LVAD) population are understudied. This pilot randomized control trial (RCT) evaluated the feasibility of a novel "smartphone app-directed and nurse-supported self-management intervention" in patients implanted with durable LVADs. Assessments included behavioral (self-efficacy and adherence), clinical (complications), and healthcare utilization (unplanned clinic, emergency room (ER) visits, and re-hospitalization) outcomes, completed at baseline (pre-hospital discharge) and months 1, 3, and 6 post-hospital discharge. Intervention patients (n = 14) had favorable patterns/trends of results across study outcomes than control patients (n = 16). Notably, intervention patients had much lower complications and healthcare utilization rates than controls. For example, intervention patients had 2 (14.3%) driveline infections in 6 months while control patients had 3 (19.0%). Additionally, at month 3, intervention patients had 0% ER visits versus 36% of control patients. At month 6, the mean cumulative number of re-hospitalizations for the control group was higher (0.9 ± 0.93) than intervention (0.3 ± 0.61) group. Despite the small sample size and limitations of feasibility/pilot studies, our outcomes data appeared to favor the novel intervention. Lessons learned from this study suggest the intervention should be implemented for 6 months post-hospital discharge. Further research is needed including large and rigorous multi-center RCTs to generate knowledge explaining the mechanism of the effect of self-management on LVAD treatment outcomes.

Influence of systemic infection and comorbidities on rehabilitation outcomes in severe acquired brain injury

BACKGROUND

Severe infectious complications are a frequent problem in patients with disability due to a severe acquired brain injury. Previous studies reported that the rehabilitation outcome is significantly lower in patients colonized or infected. However, these results could be influenced by comorbidities of those patients admitted in rehabilitation hospital with a lower functional status.

AIM

To explore the influence of systemic infection, in particular concerning multidrug resistant bacteria and analyze the role of comorbidities, as a risk factor for the development of systemic infection, on rehabilitation outcomes in patients with severe brain injury.

DESIGN

This research is a cohort, prospective-observational study, comparing patients with and without systemic infections, in terms of rehabilitation outcomes.

SETTING

An Italian Intensive Care Rehabilitation Department.

POPULATION

A group of 221 patients (mean age: 59 years, range: 16-93 years, 127 males, 94 females) with severe acquired brain injury admitted to rehabilitation hospital.

METHODS

We compared the rehabilitation outcomes between patients with and without a systemic infection (at least a positive blood culture) during the rehabilitation period. A secondary analysis was performed on 70 patients with infection versus 70 patients without infection, matched for functional status at admission. The used clinical scores were: Cumulative Illness Rating Scale for Geriatrics (CIRS-G), Coma Recovery Scale Revised (CRS-R), Glasgow Coma Scale (GCS), Functional Independence Measure (FIM), Glasgow Outcome Scale (GOS), Disability Rating Scale (DRS), Levels of Cognitive Functioning (LCF) administered at admission and discharge. Length of hospitalization and the role of comorbidities were also considered.

RESULTS

The group of patients with systemic infection (in particular due to Gram-negative bacteria) had a significantly lower outcome for 5 out 6 clinical scales and with a more than doubled length of hospitalization (P<0.001). However, these patients with, at least, a positive blood culture resulted having lower functional status at admission. In the secondary analysis, worst outcome was found in patients with positive blood culture in terms of FIM (P=0.033), GOS (P=0.048), and CRS-R (P=0.001).

CONCLUSIONS

Systemic infections during rehabilitation increased the length of hospitalization and reduce the rehabilitative outcomes, even when the analysis was performed on groups matched for the functional status at admission. Moreover, the cardiological and endocrine metabolic comorbidities seem to influence the outcome, without representing a further risk factor for systemic infection.

CLINICAL REHABILITATION IMPACT

The impact of infections during rehabilitation inpatient should be more taken into account, with specific procedures and suitable environments to avoid the diffusions of infections.

Comorbid vision and cognitive impairments in older adults hospitalized for acute myocardial infarction

Older patients presenting with acute myocardial infarction (AMI) often have comorbidities. Our objective was to examine how outcomes differ by cognitive and vision status in older AMI patients. We use data from a prospective cohort study conducted at 94 hospitals in the United States between January 2013 and October 2016 that enrolled men and women aged ≥75 years with AMI. Cognitive impairment (CI) was defined as telephone interview for cognitive status (TICS) score <27; vision impairment (VI) and activities of daily living (ADLs) were assessed by questionnaire. Of 2988 senior AMI patients, 260 (8.7%) had CI but no VI, 858 (28.7%) had VI but no CI, and 251 (8.4%) had both CI/VI. Patients in the VI/CI group were most likely to exhibit geriatric syndromes. More severe VI was associated with lower (worse) scores on the TICS (β −1.53, 95% confidence interval (CI) −1.87 to −1.18). In adjusted models, compared to participants with neither impairment, participants with VI/CI were more likely to die (hazard ratio 1.61, 95% CI 1.10–2.37) and experience ADL decline (odds ratio 2.11, 95% CI 1.39–3.21) at 180 days. Comorbid CIs and VIs were associated with high rates of death and worsening disability after discharge among seniors hospitalized for AMI. Future research should evaluate protocols to accommodate these impairments during AMI presentations and optimize decision-making and outcomes.

Evaluation of published assessment tools for comorbidity in liver transplantation: a systematic review protocol

INTRODUCTION

Liver transplantation is considered the best therapy option for end-stage liver disease. Different factors including recipient comorbidity at time of transplantation are supposed to have substantial impact on outcomes. Although several studies have focused on comorbidity assessment indices for liver transplant recipients, there is no systematic review available on the methodological details and prognostic accuracy of these instruments. The aim of this study is to systematically review recipient comorbidity assessment indices in the context of liver transplantation.

METHODS AND ANALYSIS

PubMed, Embase, Web of Science and PsyINFO databases will be searched. Studies describing, using or evaluating specific assessment tools to predict the effect of comorbidity on clinical outcomes after liver transplantation will be included. The selection will be conducted independently by two reviewers. The study characteristics and methodological information on published comorbidity assessment tools will be extracted into a predefined structural table. This approach will be deployed to systematically extract information on the validity, reliability and practical feasibility of investigated comorbidity assessment tools for comparative evaluation. Narrative information synthesis will be conducted, and additional meta-analytical comparison will be performed, if appropriate.

ETHICS AND DISSEMINATION

All data are collected from published literature. Thus, formal ethics review for the research is not required. The findings of this systematic review will be published in a peer-reviewed journal and presented at relevant conferences. The results of this systematic review will be highly relevant for further research on prognostic models, clinical decision making and optimisation of donor organ allocation.

PROSPERO REGISTRATION NUMBER

CRD42017074609.

A systematic review of heart failure dyadic self-care interventions focusing on intervention components, contexts, and outcomes

BACKGROUND

Having support from an informal carer is important for heart failure patients. Carers have the potential to improve patient self-care. At the same time, it should be acknowledged that caregiving could affect the carer negatively and cause emotional reactions of burden and stress. Dyadic (patient and informal carer) heart failure self-care interventions seek to improve patient self-care such as adherence to medical treatment, exercise training, symptom monitoring and symptom management when needed. Currently, no systematic assessment of dyadic interventions has been conducted with a focus on describing components, examining physical and delivery contexts, or determining the effect on patient and/or carer outcomes.

OBJECTIVE

To examine the components, context, and outcomes of dyadic self-care interventions.

DESIGN

A systematic review registered in PROSPERO, following PRISMA guidelines with a narrative analysis and realist synthesis.

DATA SOURCES

PubMed, EMBASE, Web of Science, PsycINFO, and Cochrane Central Register of Controlled Trials were searched using MeSH, EMTREE terms, keywords, and keyword phrases for the following concepts: dyadic, carers, heart failure and intervention. Eligible studies were original research, written in English, on dyadic self-care interventions in adult samples.

REVIEW METHODS

We used a two-tiered analytic approach including both completed studies with power to determine outcomes and ongoing studies including abstracts, small pilot studies and protocols to forecast future directions.

RESULTS

Eighteen papers - 12 unique, completed intervention studies (two quasi- and ten experimental trials) from 2000 to 2016 were reviewed. Intervention components fell into three groups - education, support, and guidance. Interventions were implemented in 5 countries, across multiple settings of care, and involved 3 delivery modes - face to face, telephone or technology based. Dyadic intervention effects on cognitive, behavioral, affective and health services utilization outcomes were found within studies. However, findings across studies were inconclusive as some studies reported positive and some non-sustaining outcomes on the same variables. All the included papers had methodological limitations including insufficient sample size, mixed intervention effects and counter-intuitive outcomes.

CONCLUSIONS

We found that the evidence from dyadic interventions to promote heart failure self-care, while growing, is still very limited. Future research needs to involve advanced sample size justification, innovative solutions to increase and sustain behavior change, and use of mixed methods for capturing a more holistic picture of effects in clinical practice.

A Systematic Review of Comorbidity Measurement Methods for Patients With Nontraumatic Brain Injury in Inpatient Rehabilitation Settings

This review summarizes comorbidity measurements used on patients with nontraumatic brain injury in inpatient rehabilitation and describes findings on measurement validation and comorbidity profiles. MEDLINE and MEDLINE In-Process, EMBASE, PsycINFO, the Cochrane Database of Systematic Reviews, Health, and Psychosocial Measurement Instruments were searched. Two reviewers screened results according to predefined inclusion and exclusion criteria. Population, statistical methods, comorbidity measurement, justification of its use, and results involving comorbidity were extracted using a standard table. Of 9476 articles retrieved, 16 were included. Comorbidity has been measured using various methods including the following: number and type within various classification systems, such as the International Disease Classification system, the Charlson comorbidity index, Centers for Medicare and Medicaid Services comorbidity tiers and patient comorbidity and complexity level values and subsets of diagnoses within nonadministrative data studies. No studies have assessed the predictive ability of the comorbidity measurements for inpatient rehabilitation outcomes in this population. Because comorbidities are common among the nontraumatic brain injury population, the predictive validity of comorbidity measurements should be assessed to determine the most appropriate measure to predict or risk adjust rehabilitation outcomes, which has implications for the development of clinical guidelines, and to inform health service research, planning, and delivery.

The challenge of comorbidity in clinical trials for multiple sclerosis

OBJECTIVE

We aimed to provide recommendations for addressing comorbidity in clinical trial design and conduct in multiple sclerosis (MS).

METHODS

We held an international workshop, informed by a systematic review of the incidence and prevalence of comorbidity in MS and an international survey about research priorities for studying comorbidity including their relation to clinical trials in MS.

RESULTS

We recommend establishing age- and sex-specific incidence estimates for comorbidities in the MS population, including those that commonly raise concern in clinical trials of immunomodulatory agents; shifting phase III clinical trials of new therapies from explanatory to more pragmatic trials; describing comorbidity status of the enrolled population in publications reporting clinical trials; evaluating treatment response, tolerability, and safety in clinical trials according to comorbidity status; and considering comorbidity status in the design of pharmacovigilance strategies.

CONCLUSION

Our recommendations will help address knowledge gaps regarding comorbidity that interfere with the ability to interpret safety in monitored trials and will enhance the generalizability of findings from clinical trials to "real world" settings where the MS population commonly has comorbid conditions.

A systematic review protocol for measuring comorbidity in inpatient rehabilitation for non-traumatic brain injury

BACKGROUND

Comorbidity can affect health-care utilization and outcomes, and the results and interpretation of risk adjustment studies that attempt to predict rehabilitation utilization and outcomes are influenced by the choice of comorbidity measurement. Although the identification of an appropriate measurement has been conducted in some populations and outcomes, this information is currently lacking for the non-traumatic brain injury (nTBI) population in inpatient rehabilitation settings. As such, this is a systematic review protocol to survey the methods used to measure comorbidities in the rehabilitation setting for patients with nTBI.

METHODS/DESIGN

MEDLINE, MEDLINE In-Process, Embase, The Cochrane Database of Systematic Reviews, PsycINFO, and Health and Psychosocial Instruments will be systematically searched using the concepts 'nTBI,' 'comorbidity,' and 'rehabilitation.' Grey matters and the reference list of eligible articles will also be searched. Study selection will be performed independently by two reviewers based on predetermined eligibility criteria through two rounds of screening using, first, the title and abstract, followed by full-text. Extracted information will include study purpose, design, and setting; data source and type; outcomes variables; statistical methods; comorbidity measurement method, rationale, justification, or validation; and results involving comorbidity. The data will be tabulated and narratively synthesized. Meta-analyses will be performed if appropriate.

SYSTEMATIC REVIEW REGISTRATION

This protocol has not been registered with PROSPERO.

DISCUSSION

This protocol provides a systematic method for surveying current practice as well as monitoring the progress on comorbidity measurement methodology and effects of comorbidity on rehabilitation outcomes for patients with nTBI. The selection of an appropriate comorbidity measurement method has implications for the interpretation of both descriptive and risk adjustment studies, and thus, the validity of evidence used to inform planning and delivery of services.