Mechanisms and Interventions for Physical Activity in Frail Cardiovascular-kidney-metabolic Syndrome Patients: A Temporal Self-Regulation Approach

This study targets the frail population with early-middle-age CKM syndrome. Grounded in the Time-limited Self-regulation Theory (TST), it employs behavioral data analysis, theoretical variable modeling, and intervention strategy development to systematically identify risk trajectories and influencing pathways of physical activity (PA) insufficiency, thereby formulating stratified and classified intervention strategies to enhance PA levels. The research comprises three key components:

Research Component 1: Risk Prediction Model for PA Insufficiency in Frail CKM Syndrome Patients Early-middle-age frail CKM syndrome patients exhibit significant PA insufficiency and behavioral variability at the disease onset. Early identification of PA evolution trends and high-risk groups is crucial for timely intervention and precise resource allocation.

Objective:

To determine "who is more likely to sustain PA insufficiency" by constructing a trajectory identification model and risk prediction tool using longitudinal data, analyzing dynamic PA behavior patterns, and quantifying multifactorial risk probabilities to support subsequent intervention mechanisms and strategy classification.

Study Design:

Exploring PA Trajectories in Frail CKM Syndrome Patients

Target Population: Early-middle-age frail CKM patients (aligned with AHA lifestyle management guidelines).

Method: Prospective longitudinal study with multi-timepoint data collection.

Analysis: Group-based trajectory modeling (GBTM) to delineate PA dynamics, identifying high-risk trends (e.g., persistent insufficiency, steep decline).

Developing a Risk Prediction Model for PA Insufficiency

Dependent Variable: PA trajectory classification (e.g., stable-high, persistent-low, fluctuating).

Predictors: Sociodemographics, health behaviors, and environmental factors.

Method: Multi-class machine learning (XGBoost) to identify key predictors and quantify risk probabilities.

Output: Interactive visualization tool for community-level screening of high-risk individuals.

Research Component 2: TST-Based Mechanisms of PA Promotion in Frail CKM Syndrome Patients

To elucidate the key determinants and moderators of PA insufficiency, this study leverages TST's six core variables:

Behavioral intention

Consistency beliefs

Self-control capacity

Delay discounting tendency

Environmental cue perception

Habit formation strength

Methodological Approach:

Dynamic Feature Engineering:

Multi-timepoint measurement of TST variables → Derived metrics (baseline level, trend, mean, variability).

Dimensionality Reduction:

LASSO regression + PCA to mitigate multicollinearity.

Predictive Modeling:

XGBoost classification (trajectory groups as outcomes) + SHAP analysis to rank variable contributions.

Causal Pathway Analysis:

Generalized structural equation modeling (GSEM) to identify mechanistic pathways.

Outcome:

Prioritized modifiable factors (e.g., self-control \> environmental cues) for tailored interventions.

Research Component 3: TST-Driven PA Promotion Strategies for Frail CKM Syndrome Patients Goal: Translate mechanistic insights into actionable, precision strategies for behavior change.

Strategy Development Framework:

Intervention Targets:

Mechanistic variables (e.g., enhancing self-control in "persistent-low" trajectory patients).

Three Strategy Archetypes:

Intrinsic Motivation Modulation (e.g., goal-setting interventions)

Social Support Activation (e.g., peer coaching)

• Monetary Choice Questionnaire (MCQ) [Time frame: Baseline , 3 months, 6 months, 9 months]
• Exercise Benefits/Barriers Scale (EBBS) [Time frame: Baseline , 3 months, 6 months, 9 months]
• Intentions [Time frame: Baseline , 3 months, 6 months, 9 months]
• Self-Report Habit Index (SRHI) [Time frame: Baseline , 3 months, 6 months, 9 months]
• Healthy Neighborhood Survey for Community-Dwelling Older Adults [Time frame: Baseline , 3 months, 6 months, 9 months]
• Brief Self-Control Scale (BSCS) [Time frame: Baseline , 3 months, 6 months, 9 months]
• Multidimensional Frailty [Time frame: baseline]
• Charlson Comorbidity Index (CCI) [Time frame: baseline]