Correlation between systemic immune-inflammation index and heart failure in elderly patients with hypertension and nursing guidance: an data analysis based on National Health and Nutrition Examination Survey

Objective To explore the relationship of the systemic immune-inflammation index (SII) with heart failure incidence in elderly people with hypertension and its nursing implications.

Methods According to the data of the National Health and Nutrition Examination Survey (NHANES) database from 1999 to 2010, a total of 5 607 hypertension patients aged 60 and above were screened out and divided into heart failure group with 437 cases and non-heart failure group with 5 170 cases. All the participants were divided into Q₁ to Q₄ groups based on their SII levels by using the quartile method, with Q₁ as the reference group. After gradually adjusting for potential confounding factors, the differences in prevalence rate of heart failure among four groups were explored by Logistic regression analysis, and subgroup analyses were conducted as well.

Results There were significant differences in race, age, education level, income level, smoking history, drinking history, body mass index (BMI), C-reactive protein, estimated glomerular filtration rate (eGFR), hemoglobin, diabetes history and coronary heart disease history between the two groups (P < 0.05). Compared with the non-heart failure group, the heart failure group had significant lower lymphocyte and platelet counts, while the neutrophil count and SII were significantly higher (P < 0.05). The result of multiple Logistic regression analysis showed a positive correlation between the increase of SII and the prevalence rate of heart failure (P < 0.05). After adjusting for related confounding factors, the values of odds ratio (OR) and 95% confidence interval (95%CI) for prevalence rate of heart failure in patients with SII from the second to the fourth quartiles were 0.80 (0.57 to 1.11), 1.14 (0.84 to 1.56) and 1.38 (1.02 to 1.87) respectively (P_trend=0.006). Subgroup analyses were carried out according to gender, diabetes, coronary heart disease, hyperlipidemia and eGFR, and the results showed that among women without coronary heart disease, with eGFR≤90 mL/(min·1.73 m²) and with or without hyperlipidemia, participants with the highest quartile of SII (Q₄) had a significant higher risk of heart failure than those with Q₁ (P_trend < 0.05).

Conclusion SII may be independently associated with the prevalence rate of heart failure in elderly people with hypertension, and has guiding significance for clinical and nursing work.