Predictors of 90-Day Re-hospitalization in Heart Failure: Insights From a Prospective Observational Study in a Tertiary Care Setting

BACKGROUND: Heart failure (HF) remains a leading cause of recurrent hospital readmissions, particularly during the early post-discharge period (first 90 days). The present study aimed to evaluate sociodemographic, clinical, biochemical, and follow-up determinants of 90-day unplanned readmission among adults admitted with HF at a tertiary cardiac center. METHODS: A prospective observational study was conducted among adults aged ≥18 years with clinically and echocardiographically confirmed HF. Baseline demographics, clinical characteristics, comorbidities, laboratory parameters, medications, and functional status were documented. Participants were followed for 90 days after discharge to assess readmission. Both single-variable and multivariable logistic regression techniques were utilized, and outcomes were summarized in terms of adjusted odds ratios along with 95% confidence intervals (CI). RESULTS: Of 300 patients, 270 (90%) completed follow-up, and 78 of these (28.9%) were readmitted within 90 days; 30 patients (10%) were lost to follow-up. Compared with those not readmitted, patients who were readmitted were older and predominantly from lower socioeconomic groups (p < 0.05). Readmission was more frequent among those with New York Heart Association (NYHA) Class III symptoms, chronic kidney disease (CKD), and anemia (all p ≤ 0.001). They also had lower renal function and serum sodium with markedly higher N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels (p < 0.001). Failure to adhere to the treatment regimen (48.7% vs 21.4%; p < 0.001) and delayed post-discharge review within seven days (57.7% vs 42.3%; p = 0.003) were found to substantially increase the likelihood of readmission. Multivariable logistic regression demonstrated that patients categorized as NYHA Class III had a significantly greater likelihood of readmission (adjusted odds ratio (AOR) = 2.18; 95% confidence interval (CI): 1.15-4.13; p = 0.017). CKD also showed an independent relationship with readmission (AOR = 2.34; 95% CI: 1.02-5.37; p = 0.044). Each 1000 pg/mL increase in NT-proBNP concentration was associated with a 21% rise in the odds of readmission (per 1000 pg/mL; AOR = 1.21; 95% CI: 1.07-1.37; p = 0.002). Furthermore, individuals not receiving angiotensin-converting enzyme inhibitors or angiotensin receptor blockers exhibited higher readmission risk (AOR = 2.87; 95% CI: 1.38-5.97; p = 0.005). Suboptimal medication compliance (AOR = 2.95; 95% CI: 1.52-5.72; p = 0.001) and lack of timely post-discharge follow-up (AOR = 1.98; 95% CI: 1.05-3.73; p = 0.034) were also significant predictors. CONCLUSION: Ninety-day readmission in HF was frequent and independently associated with advanced functional class, renal dysfunction, elevated NT-proBNP, lack of angiotensin-converting enzyme inhibitor or angiotensin receptor blocker therapy, poor adherence, and delayed post-discharge review. Targeted discharge education, adherence support, optimization of renin-angiotensin system blockade, and early clinic review may reduce preventable readmissions.