State Key Laboratory for Innovation and Transformation of Luobing Theory, Jinan, China.
Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, Jinan, China.
Cardiovasc Diabetol. 2024 Sep 11;23(1):334. doi: 10.1186/s12933-024-02430-9.
Although the "obesity paradox" is comprehensively elucidated in heart failure (HF) with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), the role of body composition in left ventricular (LV) remodeling, LV reverse remodeling (LVRR), and clinical outcomes is still unclear for HF with mildly reduced ejection fraction (HFmrEF).
Our study is a single-centre, prospective, and echocardiography-based study. Consecutive HFmrEF patients, defined as HF patients with a left ventricular ejection fraction (LVEF) between 40 and 49%, between January 2016 to December 2021 were included. Echocardiography was re-examined at 3-, 6-, and 12-month follow-up to assess the LVRR dynamically. Body mass index (BMI), fat mass, fat-free mass, percent body fat (PBF), CUN-BAE index, and lean mass index (LMI) were adopted as anthropometric parameters in our study to assess body composition. The primary outcome was LVRR, defined as: (1) a reduction higher than 10% in LV end-diastolic diameter index (LVEDDI), or a LVEDDI < 33 mm/m, (2) an absolute increase of LVEF higher than 10 points compared with baseline echocardiogram, or a follow-up LVEF ≥50%. The secondary outcome was a composite of re-hospitalization for HF or cardiovascular death.
A total of 240 HFmrEF patients were enrolled in our formal analysis. After 1-year follow-up based on echocardiography, 113 (47.1%) patients developed LVRR. Patients with LVRR had higher fat mass (21.7 kg vs. 19.3 kg, P = 0.034) and PBF (28.7% vs. 26.6%, P = 0.047) compared with those without. The negative correlation between anthropometric parameters and baseline LVEDDI was significant (all P < 0.05). HFmrEF patients with higher BMI, fat mass, PBF, CUN-BAE index, and LMI had more pronounced and persistent increase of LVEF and decline in LV mass index (LVMI). Univariable Cox regression analysis revealed that higher BMI (HR 1.042, 95% CI 1.002-1.083, P = 0.037) and fat mass (HR 1.019, 95% CI 1.002-1.036, P = 0.026) were each significantly associated with higher cumulative incidence of LVRR for HFmrEF patients, while this relationship vanished in the adjusted model. Mediation analysis indicated that the association between BMI and fat mass with LVRR was fully mediated by baseline LV dilation. Furthermore, higher fat mass (aHR 0.957, 95% CI 0.917-0.999, P = 0.049) and PBF (aHR 0.963, 95% CI 0.924-0.976, P = 0.043) was independently associated with lower risk of adverse clinical events.
Body composition played an important role in the LVRR and clinical outcomes for HFmrEF. For HFmrEF patients, BMI and fat mass was positively associated with the cumulative incidence of LVRR, while higher fat mass and PBF predicted lower risk of adverse clinical events but not LMI.
尽管“肥胖悖论”在射血分数降低的心力衰竭（HFrEF）和射血分数保留的心力衰竭（HFpEF）中得到了全面阐述，但身体成分在左心室（LV）重构、LV 逆重构（LVRR）和临床结局中的作用对于射血分数轻度降低的心力衰竭（HFmrEF）仍不清楚。
我们的研究是一项单中心、前瞻性的、基于超声心动图的研究。连续纳入 2016 年 1 月至 2021 年 12 月期间患有左心室射血分数（LVEF）在 40%至 49%之间的 HFmrEF 患者。在 3、6 和 12 个月的随访中进行超声心动图复查，以动态评估 LVRR。体重指数（BMI）、脂肪量、去脂体重、体脂百分比（PBF）、CUN-BAE 指数和瘦体重指数（LMI）被用作本研究中的人体测量参数，以评估身体成分。主要结局是 LVRR，定义为：（1）LV 舒张末期内径指数（LVEDDI）降低超过 10%，或 LVEDDI<33mm/m；（2）与基线超声心动图相比，LVEF 绝对增加超过 10 个点，或随访 LVEF≥50%。次要结局是心力衰竭或心血管死亡的再住院复合事件。
共有 240 例 HFmrEF 患者纳入正式分析。根据超声心动图，1 年后有 113 例（47.1%）患者发生 LVRR。与未发生 LVRR 的患者相比，发生 LVRR 的患者脂肪量（21.7kg 比 19.3kg，P=0.034）和 PBF（28.7%比 26.6%，P=0.047）更高。人体测量参数与基线 LVEDDI 呈显著负相关（均 P<0.05）。BMI、脂肪量、PBF、CUN-BAE 指数和 LMI 较高的 HFmrEF 患者 LVEF 升高更显著且持续，LV 质量指数（LVMI）下降更显著。单变量 Cox 回归分析显示，较高的 BMI（HR 1.042，95%CI 1.002-1.083，P=0.037）和脂肪量（HR 1.019，95%CI 1.002-1.036，P=0.026）与 HFmrEF 患者更高的 LVRR 累积发生率显著相关，但在调整模型中这种关系消失了。中介分析表明，BMI 和脂肪量与 LVRR 的相关性完全由基线 LV 扩张介导。此外，较高的脂肪量（aHR 0.957，95%CI 0.917-0.999，P=0.049）和 PBF（aHR 0.963，95%CI 0.924-0.976，P=0.043）与不良临床事件的风险降低独立相关。
身体成分在 HFmrEF 的 LVRR 和临床结局中起重要作用。对于 HFmrEF 患者，BMI 和脂肪量与 LVRR 的累积发生率呈正相关，而较高的脂肪量和 PBF 预测不良临床事件的风险较低，但与 LMI 无关。
