Zhang Ying, Hu Wenting, Zhou Zhilian, Wang Xiuming, Lin ChanChan
Department of Anorectal Surgery, Chengdu Integrated TCM (Traditional Chinese Medicine) & Western Medicine Hospital, Chengdu First People's Hospital, Sichuan, China.
Department of Neurology, Chengdu Integrated TCM & Western Medicine Hospital, Chengdu First People's Hospital, Sichuan, China.
J Health Popul Nutr. 2025 Aug 22;44(1):305. doi: 10.1186/s41043-025-01050-7.
Fecal incontinence (FI), a prevalent condition affecting approximately 7.7% of the global population and 8.3% of Americans, significantly impairs quality of life. Although FI is closely associated with obesity, the specific impact of weight-adjusted waist index (WWI) on FI remains unclear. This study aimed to investigate the association between this novel anthropometric indicator, WWI, and FI among American adults.
This cross-sectional study enrolled 12,922 participants from the National Health and Nutrition Examination Survey (NHANES). WWI was calculated as waist circumference (cm) divided by the square root of weight (kg). FI was defined as any involuntary loss of mucus, liquid, or solid stool in the past month, assessed via the NHANES Bowel Health Questionnaire. Weighted multivariable logistic regression analyses were performed to evaluate the association between WWI and FI. Furthermore, we utilized smoothing curve fitting to elucidate potential linear relationships. The predictive performance of WWI, body mass index (BMI), and waist circumference (WC) in relation to FI was assessed using the receiver operating characteristic curve analysis and DeLong's non-parametric test.
The overall prevalence of FI was 8.14%. Weighted multivariable logistic regression analyses indicated that each one-unit increase in WWI was associated with a 36% higher prevalence of FI (OR = 1.36, 95% CI:1.20-1.55; P < 0.001). When WWI was categorized into tertiles and compared to the lowest tertile, the highest tertile maintained a positive association with FI (OR = 1.63, 95% CI:1.31-2.02; P < 0.001). Smoothing curve fitting revealed a linear dose-response relationship between WWI and FI. Subgroup analysis indicated no significant interactions (all P > 0.05). Additionally, our results suggested that the correlation between WWI and FI was stronger than that between BMI or WC and FI.
WWI is independently associated with FI, suggesting its potential utility in clinical assessment. WWI may refine risk stratification in obesity management strategies.
大便失禁（FI）是一种普遍存在的病症，影响着全球约7.7%的人口以及8.3%的美国人，严重损害生活质量。尽管FI与肥胖密切相关，但体重调整腰围指数（WWI）对FI的具体影响仍不明确。本研究旨在调查这一新型人体测量指标WWI与美国成年人FI之间的关联。
这项横断面研究纳入了来自美国国家健康与营养检查调查（NHANES）的12922名参与者。WWI的计算方法为腰围（厘米）除以体重（千克）的平方根。FI定义为过去一个月内出现的任何黏液、液体或固体粪便的不自主排出，通过NHANES肠道健康问卷进行评估。进行加权多变量逻辑回归分析以评估WWI与FI之间的关联。此外，我们利用平滑曲线拟合来阐明潜在的线性关系。使用受试者工作特征曲线分析和德龙非参数检验评估WWI、体重指数（BMI）和腰围（WC）对FI的预测性能。
FI的总体患病率为8.14%。加权多变量逻辑回归分析表明，WWI每增加一个单位，FI的患病率就会高出36%（OR = 1.36，95% CI：1.20 - 1.55；P < 0.001）。当将WWI分为三分位数并与最低三分位数进行比较时，最高三分位数与FI仍保持正相关（OR = 1.63，95% CI：1.31 - 2.02；P < 0.001）。平滑曲线拟合揭示了WWI与FI之间的线性剂量反应关系。亚组分析表明无显著交互作用（所有P > 0.05）。此外，我们的结果表明WWI与FI之间的相关性强于BMI或WC与FI之间的相关性。
WWI与FI独立相关，表明其在临床评估中的潜在效用。WWI可能会优化肥胖管理策略中的风险分层。
