Validation of the Lee-Jones theoretical model of fear of cancer recurrence among breast cancer survivors using a structural equation modeling approach.

OBJECTIVE: The Lee-Jones model posits that antecedent individual and interpersonal factors predicate the development of fear of cancer recurrence (FCR) through cognitive and emotional processing, which further to behavioral, emotional, and/or physiological responses. We analyzed data from FoRtitude, a FCR intervention grounded in the Lee-Jones FCR model, to evaluate associations between FCR antecedents, resources (e.g., breast cancer self-efficacy, BCSE) and psychological and behavioral consequences. METHODS: Women with breast cancer who completed treatment and reported clinically elevated levels of FCR were randomized into a 4-week online psychosocial intervention or contact control group. We assessed BCSE, FCR, and physical activity, anxiety and depression, or symptoms at baseline, 4 and 8 weeks. Separate structural equation models were constructed with both baseline data and change scores (baseline-8 weeks) to examine the pathways linking BCSE, FCR and: (1) physical activity; (2) anxiety and depression; and (3) symptoms (fatigue, sleep disturbance, cognitive concerns). RESULTS: At baseline, higher levels of BCSE were associated with lower levels of FCR. Higher FCR was associated with worse psychological effects and symptoms but not behavioral response. Change models revealed that an increase in BCSE was associated with a decrease in FCR at 8-week assessment, which was associated with reductions in psychological effects. A change in BCSE was also directly associated with reductions in psychological effects. CONCLUSIONS: Results support the Lee-Jones model as a foundation for FCR interventions among breast cancer survivors. Replicability among varied populations is needed to examine effects on behavioral outcomes of FCR such as health care utilization. CLINICAL TRIALS REGISTRATION: NCT03384992.

Factors influencing health behaviour, blood pressure control, and disability in hypertensive ischaemic stroke patients after a comprehensive reminder intervention.

AIMS: To test prospective pathways of a Comprehensive Reminder System based on the Health Belief Model (CRS-HBM), stroke knowledge, health belief in health behaviour, blood pressure (BP) control, and disability in hypertensive ischaemic stroke patients at 6-month postdischarge. DESIGN: A nested cohort study design. METHODS: Data were derived from a randomized controlled trial evaluating the effects of the intervention (N = 174, performed during February 2015 - March 2016). Data were collected by questionnaires and analysed in structural equation modelling in Mplus software. RESULTS: The proposed model provided a good fit to the data. This model accounted for 51.5% of the variance in health behaviour, 34.1% in BP control, and 5.7% in modified Rankin Scale score at 6-month postdischarge. The CRS-HBM had: (a) direct positive effect (ß = .391, p < .001) and indirect positive effects (ß = .186, p = .002) on health behaviour; (b) direct positive effect (ß = .356, p < .001) and indirect positive effects (ß = .183, p = .009) on BP control; and (c) indirect negative effect (ß = -.146, p = .008) on disability. Being female was linked to better health behaviour. Higher education predicted higher level of stroke knowledge and health belief. CONCLUSIONS: The CRS-HBM can not only directly but also indirectly improve patients' health behaviours by improving their health knowledge or health belief. Better health behaviour can improve patients' BP control and reduce disability. Therefore, nurses need to pay more attention to not only patients' health knowledge but also their health belief when providing education. IMPACT: The CRS-HBM intervention accounted for 51.5% of variance in health behaviour, 34.1% in BP control, and 5.7% in modified Rankin Scale score at 6-month postdischarge. This research can help nurses improve health education strategies in postdischarge and community contexts to achieve better health results.

Determinants of hospitalization in Chinese patients with type 2 diabetes receiving a peer support intervention and JADE integrated care: the PEARL randomised controlled trial.

BACKGROUND: In a randomized controlled trial of 628 Chinese patients with type 2 diabetes receiving multidisciplinary care in the Joint Asia Diabetes Evaluation (JADE) Progam, 372 were randomized to receive additional telephone-based peer support (Peer Empowerment And Remote communication Linked by information technology, PEARL) intervention. After 12 months, all-cause hospitalization was reduced by half in the PEARL group especially in those with high Depression Anxiety and Stress Scale (DASS) scores. METHODS: We used stratified analyses, negative binomial regression, and structural equation modelling (SEM) to examine the inter-relationships between emotions, self-management, cardiometabolic risk factors, and hospitalization. RESULTS: Hospitalized patients were older, more likely to have heart or kidney disease, and negative emotions than those without hospitalization. Patients with high DASS score who did not receive peer support had the highest hospitalization rates. After adjustment for confounders, peer support reduced the frequency of hospitalizations by 48% with a relative risk of 0.52 (95% CI 0·35-0·79;p = 0·0018). Using SEM, improvement of negative emotions reduced treatment nonadherence (Est = 0.240, p = 0.034) and hospitalizations (Est=-0.218, p = 0.001). The latter was also reduced by an interactive term of peer support and chronic kidney disease (Est = 0.833, p = < 0.001) and that of peer support and heart disease (Est = 0.455, p = 0.001). CONCLUSIONS: In type 2 diabetes, improvement of negative emotions and peer support reduced hospitalizations, especially in those with comorbidities, in part mediated through improving treatment nonadherence. Integrating peer support is feasible and adds value to multidisciplinary care, augmented by information technology, especially in patients with comorbidities. TRIAL REGISTRATION: NCT00950716 Registered July 31, 2009.

The influence of participation on health-related quality of life in stroke patients.

PURPOSE: Limitations in participation may have independent influences on health-related quality of life (HRQOL) at early and late phases of stroke recovery. METHODS: Consecutive stroke patients were interviewed at months 3 and 12 after stroke for modified Barthel Index (MBI), geriatric depression scale (GDS) and WHO QOL questionnaire (abbreviated Hong Kong version). London handicap scale (LHS) was used to measure limitations in participation. The influence of the six LHS domains on the four HRQOL domains, adjusted for MBI and GDS was analysed by structural equation modelling with a two-component analysis. RESULTS: Complete data were collected in 500 and 433 subjects at months 3 and 12, respectively. On multivariate analysis, after adjustment for MBI and GDS, the independence and social integration domains of LHS had significant influence on physical and social HRQOL, respectively, at both 3 and 12 months post-stroke. The occupation domain was a significant factor of physical and environmental HRQOL at month 12, but not at month 3. Economic sufficiency had more influence on HRQOL at month 3 than at month 12. The mobility and orientation domains had no significant negative influence on HRQOL. CONCLUSIONS: In stroke patients, participation had significant independent influences on HRQOL.

A semiparametric Bayesian approach for structural equation models.

In the development of structural equation models (SEMs), observed variables are usually assumed to be normally distributed. However, this assumption is likely to be violated in many practical researches. As the non-normality of observed variables in an SEM can be obtained from either non-normal latent variables or non-normal residuals or both, semiparametric modeling with unknown distribution of latent variables or unknown distribution of residuals is needed. In this article, we find that an SEM becomes nonidentifiable when both the latent variable distribution and the residual distribution are unknown. Hence, it is impossible to estimate reliably both the latent variable distribution and the residual distribution without parametric assumptions on one or the other. We also find that the residuals in the measurement equation are more sensitive to the normality assumption than the latent variables, and the negative impact on the estimation of parameters and distributions due to the non-normality of residuals is more serious. Therefore, when there is no prior knowledge about parametric distributions for either the latent variables or the residuals, we recommend making parametric assumption on latent variables, and modeling residuals nonparametrically. We propose a semiparametric Bayesian approach using the truncated Dirichlet process with a stick breaking prior to tackle the non-normality of residuals in the measurement equation. Simulation studies and a real data analysis demonstrate our findings, and reveal the empirical performance of the proposed methodology. A free WinBUGS code to perform the analysis is available in Supporting Information.

Longitudinal analysis of quality of life for stroke survivors using latent curve models.

BACKGROUND AND PURPOSE: For the survivors, activities of daily living, handicap, and depression have a significant impact on health-related quality of life (HRQOL). How the dynamic changes of these variables relate to HRQOL over time in the subacute phase of stroke recovery has not been investigated. The objective of this study was to study longitudinal behaviors of HRQOL of the stroke survivors in relation to the changes in activities of daily living, handicap, and depression after stroke. METHODS: This was a prospective cohort study of first disabling patients with stroke. Subjects were interviewed at 3, 6, and 12 months after stroke for modified Barthel Index, London Handicap Scale, Geriatric Depression Scale, and the World Health Organization Quality of Life questionnaire (abbreviated Hong Kong version). A latent curve model was developed to analyze how the dynamic changes in activities of daily living, handicap, and depressive mood related to the changes in HRQOL. RESULTS: Two hundred forty-seven of 303 patients (82%) followed up at 3 months after stroke could complete the quality-of-life questionnaire. Their mean age was 68.8 years. The latent curve model analysis revealed that initial physical health HRQOL was independently associated with activities of daily living, handicap, and depression. The other 3 HRQOL domain scores were primarily associated with depression only. The rates of change in all 4 domains of HRQOL were significantly and inversely associated with rate of change in the Geriatric Depression Scale only. CONCLUSIONS: Change in mood in the postacute phase of stroke recovery is the most significant determinant of change in HRQOL. More attention should be paid to the detection and management of poststroke depression.