Li Zhiqiang, Gong Xinran, Cui Xin, Zhang Wuping, Wang Yanding, Wu Di, Yang Meitao, Jia Xinjing, Duan Chunyuan, Liu Lisha, Guo Jinpeng, Jia Ruizhong, Zhang Xiushan, Chen Yong, Tang Yue, Liu Miao, Wang Yong
School of Public Health, China Medical University, Shenyang, China.
Chinese People's Liberation Army Center for Disease Control and Prevention, Dongda Street No.20 in Fengtai District, Beijing, 100071, China.
Aging Clin Exp Res. 2023 Mar;35(3):689-698. doi: 10.1007/s40520-023-02346-6. Epub 2023 Feb 16.
Epidemiological studies have reported that among participants with impaired cognitive, overweight and mild obesity are associated with substantially improved survival, this finding has been termed the "obesity paradox" and has led to uncertainty about secondary prevention.
To explore whether the association of BMI with mortality differed in different MMSE score, and whether the obesity paradox in patient with cognitive impairment (CI) is real.
The study used data from CLHLS, a representative prospective population-based cohort study in China, which included 8348 participants aged ≥ 60 years between 2011 and 2018. The independent association between BMI and mortality in differed MMSE score by calculating hazard ratios (HRs) in multivariate Cox regression analysis.
During a median (IQR) follow-up of 41.18 months, a total of 4216 participants died. In the total population, underweight increased the risk of all-cause mortality (HRs, 1.33; 95% CI 1.23-1.44), compared with normal weight, and overweight was associated with a decreased risk of all-cause mortality (HR 0.83; 95% CI 0.74-0.93). However, compared to normal weight, only underweight was associated with increased mortality risk among participants with MMSE scores of 0-23, 24-26, 27-29, and 30, and the fully-adjusted HRs (95% CIs) for mortality were 1.30 (1.18, 1.43), 1.31 (1.07, 1.59), 1.55 (1.34, 1.80) and 1.66 (1.26, 2.20), respectively. The obesity paradox was not found in individuals with CI. Sensitivity analyses carried out had hardly any impact on this result.
We found no evidence of an obesity paradox in patients with CI, compared with patients of normal weight. But underweight individuals may have increased mortality risk whether in the population with CI or not. And overweight/obese people with CI should continue to aim for normal weight.
流行病学研究报告称，在认知功能受损的参与者中，超重和轻度肥胖与生存率显著提高相关，这一发现被称为“肥胖悖论”，并导致了二级预防方面的不确定性。
探讨不同MMSE评分下BMI与死亡率的关联是否不同，以及认知障碍（CI）患者中的肥胖悖论是否真实存在。
该研究使用了中国健康与养老追踪调查（CLHLS）的数据，这是一项具有代表性的基于人群的前瞻性队列研究，纳入了2011年至2018年间年龄≥60岁的8348名参与者。通过在多变量Cox回归分析中计算风险比（HRs），分析不同MMSE评分下BMI与死亡率之间的独立关联。
在中位（IQR）随访41.18个月期间，共有4216名参与者死亡。在总人群中，与正常体重相比，体重过轻会增加全因死亡率风险（HRs为1.33；95%CI为1.23 - 1.44），超重与全因死亡率风险降低相关（HR为0.83；95%CI为0.74 - 0.93）。然而，与正常体重相比，在MMSE评分为0 - 23、24 - 26、27 - 29和30的参与者中，只有体重过轻与死亡率风险增加相关，死亡率的完全调整HRs（95%CI）分别为1.30（1.18，1.43）、1.31（1.07，1.59）、1.55（1.34，1.80）和1.66（1.26，2.20）。在CI个体中未发现肥胖悖论。进行的敏感性分析对这一结果几乎没有影响。
与正常体重的患者相比，我们没有发现CI患者存在肥胖悖论的证据。但无论是否患有CI，体重过轻的个体可能有更高的死亡风险。患有CI的超重/肥胖人群仍应努力实现正常体重。
