Department of Internal Medicine, Rehabilitation and Geriatrics, Geneva University Hospitals, 3, chemin Pont-Bochet, 1226 Thônex, Switzerland.
J Gerontol A Biol Sci Med Sci. 2013 Jun;68(6):705-11. doi: 10.1093/gerona/gls207. Epub 2012 Oct 10.
Association between body mass index (BMI) and long-term mortality is poorly studied in older hospitalized populations.
The researchers prospectively studied the impact of the BMI, comorbidities, and malnutrition on long-term mortality in 444 patients (mean age 85.3±6.7 years; 74.0% women) receiving geriatric inpatient care. All-cause mortality was determined using simple and multiple Cox proportional hazard models.
Higher BMI was associated with a higher prevalence of diabetes, hypertension, and heart failure, but with a lower prevalence of malignancies. Four-year all-cause mortality was inversely associated with a BMI greater than or equal to 30kg/m(2) (hazard ratio = 0.59, p = .037) and positively associated with age, male gender, several individual comorbidities, and the global disease load determined by the Cumulative Illness Rating scale. The inverse association between a BMI greater than or equal to 30 and mortality remained significant after adjustment for age, gender, smoking, individual comorbidities (including heart failure and malignancies), Cumulative Illness Rating scale scores, and malnutrition parameters (hazard ratio = 0.52, p = .015). One-year mortality was associated with the Cumulative Illness Rating scale score but not with BMI categories. There were no survival differences between patients in low (<20.0) and intermediate (20.0-24.9 and 25.0-29.9) BMI categories.
A BMI greater than or equal to 30 is associated with better long-term survival in hospitalized older patients, even after extensive adjustment for comorbidities, malnutrition, and smoking. Conversely, a low BMI (<20-25) is not associated with excess mortality, likely due to the overriding impact of multiple comorbidities. The researchers' observations have important implications for the mortality risk stratification in older high-risk patients.
体重指数（BMI）与长期死亡率之间的关系在老年住院人群中研究甚少。
研究人员前瞻性研究了 BMI、合并症和营养不良对 444 名（平均年龄 85.3±6.7 岁；74.0%为女性）接受老年住院治疗患者长期死亡率的影响。使用简单和多 Cox 比例风险模型确定全因死亡率。
较高的 BMI 与糖尿病、高血压和心力衰竭的患病率较高相关，但与恶性肿瘤的患病率较低相关。4 年全因死亡率与 BMI 大于或等于 30kg/m²呈负相关（风险比=0.59，p=0.037），与年龄、男性、几种单一合并症和累积疾病评分（Cumulative Illness Rating scale，CIRS）确定的全球疾病负担呈正相关。在调整年龄、性别、吸烟、单一合并症（包括心力衰竭和恶性肿瘤）、CIRS 评分和营养不良参数后，BMI 大于或等于 30 与死亡率之间的负相关仍然显著（风险比=0.52，p=0.015）。1 年死亡率与 CIRS 评分相关，而与 BMI 类别无关。低（<20.0）和中（20.0-24.9 和 25.0-29.9）BMI 类别之间的患者生存率无差异。
在接受广泛合并症、营养不良和吸烟调整后，BMI 大于或等于 30 与住院老年患者的长期生存相关，即使是这样。相反，低 BMI（<20-25）与超额死亡率无关，这可能是由于多种合并症的压倒性影响。研究人员的观察结果对老年高危患者的死亡率风险分层具有重要意义。
