Frailty and 6-Month Clinical Outcomes in Elderly Patients With Heart Failure and Left Ventricular Ejection Fraction >40%

This observational cohort study aims to evaluate the prevalence of frailty and its association with six-month clinical outcomes, including hospitalization and mortality, in elderly patients with heart failure (HF) and left ventricular ejection fraction (LVEF) >40%.

The study is conducted at the Cardiology outpatient clinics of Thong Nhat Hospital and the Heart Failure Clinic of the University Medical Center, Ho Chi Minh City, Vietnam. A total of approximately 301 patients aged ≥60 years with HF and LVEF >40% (per ESC 2021 criteria) will be enrolled. Baseline assessments include demographic and clinical characteristics, geriatric syndromes, and laboratory findings. Frailty will be assessed using Fried criteria; functional status using Katz ADL and Lawton IADL; nutritional status using the Mini Nutritional Assessment (MNA); depression using the Geriatric Depression Scale-15 (GDS-15); and polypharmacy, comorbidities, and falls will also be recorded.

Participants will be followed for six months to collect data on hospitalizations, mortality, and other adverse clinical outcomes. Data collection will be performed by trained investigators using standardized case report forms (CRFs) and entered into a secure electronic database. Data will undergo regular quality checks for accuracy, completeness, and consistency, with predefined range and logic checks, and source data verification against medical records for a random sample of participants.

Standard Operating Procedures (SOPs) are implemented to ensure uniformity in patient recruitment, informed consent, data collection, follow-up, and adverse event reporting. A data dictionary describing all variables, coding schemes, and normal reference ranges has been developed and will be maintained. Missing data will be documented and addressed using appropriate imputation or sensitivity analyses as outlined in the statistical analysis plan (SAP).

The sample size of approximately 301 participants is based on an expected frailty prevalence of ~50% in this population, allowing estimation with acceptable precision and adequate power to detect associations with outcomes. Statistical analyses will include descriptive statistics, Kaplan-Meier survival analysis, and multivariable regression modeling to assess the relationship between frailty and clinical outcomes while adjusting for potential confounders.