中年女性膳食热量构成与痴呆的相关性研究

Relationship between dietary calorie structure and dementia in middle-aged and elderly women

目的研究中年女性每日膳食热量结构与痴呆的关系。方法本组数据来自美国妇女健康研究(1996至1997年),痴呆通过参与者或其家属自评问卷的方式评估。患有痴呆的研究对象纳入痴呆组(n=974),其余纳入对照组(n=1790)。膳食摄入量由1995年版饮食频率调查问卷估算,Mann-Whitney U比较两组均值的差异,卡方检验比较率的差异,Logistic回归分析膳食热量构成与痴呆之间的关系,限制性三次样条回归分析痴呆风险随膳食热量构成变化的非线性关系。结果痴呆组的种族/人种构成与对照组相比差异具有统计学意义(χ2=32.720,P<0.001)。痴呆组血清三酰甘油水平高于对照组,差异具有统计学意义(Z=-1.966,P=0.049)。痴呆组每日摄入的蛋白质供能比低于对照组[对照组15.70%(13.39%~17.96%),痴呆组15.18%(13.02%~17.52%),Z=-3.521,P<0.001],而甜食供能比高于对照组[对照组12.15%(6.38%~21.31%),痴呆组14.09%(6.38%~21.31%),Z=-3.388,P=0.001]。在未调整模型中,蛋白质供能比和酒精供能比与痴呆的发生呈负相关,OR(95%CI)分别为0.961(0.939~0.983)和0.983(0.965~1.000),而甜食供能比与痴呆风险呈正比,OR(95%CI)为1.010(1.003~1.017),这种关系在调整了年龄后依然存在。在充分调整混杂因素年龄、种族和三酰甘油后,蛋白质供能比和甜食供能比与痴呆的关系仍然存在,OR(95%CI)分别为0.966(0.943~0.989)和1.010(1.003~1.016)。限制性三次样条回归表明,随着蛋白质供能比所占比例的升高,痴呆风险先快速下降,而后趋于平稳;随着甜食供能比的升高,痴呆风险先快速上升,随后放缓并有下降的趋势;随着甜食/蛋白质供能比的升高,痴呆风险快速升高,随后处于平台期。结论每日膳食中蛋白质供能比与痴呆风险呈负相关,甜食供能比与痴呆风险呈正相关。由于是横断面研究,不能确定蛋白质、甜食供能比与痴呆的因果关系。

Objective To study the relationship between dietary calorie structure and dementia in middle-aged and elderly women.Methods Data for the present study were obtained from the Study of Women’s Health Across the Nation(SWAN).Dietary intake was estimated using the 1995 Dietary Frequency Questionnaire.Mann-Whitney U test was used to compare the difference of mean values between the two groups.Logistic regression analysis was used to assess the relationship between dietary calorie structure and dementia.Restricted cubic spline analysis was used to examine if there was a non-linear relationship between them.Results The racial composition of the dementia group was significantly different from that of the control group(χ2=32.720,P<0.001).The serum triglyceride level in the dementia group was significantly higher than that in the control group(Z=-1.966,P=0.049).The daily intake of protein calories in the dementia group was lower than that in the control group(control group:15.70%(13.39%-17.96%),dementia group:15.18%(13.02%-17.52%),Z=-3.521,P<0.001),while the sweet calories in dementia group were higher than those in the control group(control group:12.15%(6.38%-21.31%),dementia group:14.09%(6.38%-21.31%),Z=-3.521,P=0.001).In the unadjusted model,protein calorie and alcohol calorie were inversely correlated with dementia,OR and 95%CI were 0.961%(0.939%-0.983%)and 0.983(0.965-1.000),respectively.Sweet calories were positively correlated with dementia risk,OR and 95%CI were 1.010(1.003-1.017).This relationship persisted after adjusting for age.After adjusting the age,race,and TG of the confounding factors,the relationships of protein calorie and sweet calorie with dementia remained intrinsic after adjusting the confounding factors adequately;the OR and 95%CI were 0.966(0.943-0.989)and 1.010(1.003-1.016),respectively.Restricted cubic spline regression showed that the risk of dementia decreased rapidly and then stabilized with the increase of protein calorie proportion.With the increase of the proportion of sweets in calories,the risk of dementia first increased rapidly,then slowed down,and then decreased.The risk of dementia increased rapidly with the increase in sweetener/protein calories,and then reached plateau stage.Conclusions This study found a negative correlation between the proportion of protein calories in the daily diet and the risk of dementia.Sweet calories were positively correlated with dementia risk.However,as this was a cross-sectional study,the causal relationship between protein and sweet intake and dementia could not be determined.