Greenberg J A, Axen K V, Schnoll R, Boozer C N
Department of Health and Nutrition Sciences, Brooklyn College, City University of New York, Brooklyn, NY 11210, USA.
Int J Obes (Lond). 2005 Sep;29(9):1121-9. doi: 10.1038/sj.ijo.0802999.
To assess the effect of weight change on the relationship between coffee and tea consumption and diabetes risk.
Prospective cohort study, using data from the First National Health and Nutrition Examination Survey Epidemiologic Follow Up Study. Survival analyses were conducted using 301 selfreported cases of diabetes and eight documented diabetes deaths during an 8.4-y follow-up.
A total of 7006 subjects aged 32-88 y with no reported history of diabetes were included in the study.
For all subjects combined, increases in consumption of ground-caffeinated coffee and caffeine at baseline were followed by decreases in diabetes risk during follow-up. There were significant statistical interactions between age and consumption of caffeine (P=0.02) and ground-caffeinated coffee (P=0.03). Age-stratified analysis showed that the decrease in diabetes risk only applied to < or =60-y-old subjects, for whom the decrease in diabetes risk also obtained for ground-decaffeinated coffee and regular tea. The multivariate hazard ratio (HR) and 95% confidence interval for a 2 cups/day increment in the intake of ground-caffeinated coffee, ground-decaffeinated coffee and regular tea was 0.86 (0.75-0.99), 0.58 (0.34-0.99) and 0.77 (0.59-1.00), respectively. The diabetes risk was negatively related to the consumption in a dose-response manner. There were strong statistical interactions between prior weight change and beverage consumption for < or =60-y-old subjects. Further analysis revealed that the decrease in diabetes risk only applied to those who had lost weight, and that there was a positive dose-response relationship between diabetes risk and weight change. For example, the multivariate HR and 95% confidence interval for >0 vs 0 cups/day of ground-decaffeinated coffee was 0.17 (0.04-0.74), 0.52 (0.19-1.42), 0.77 (0.30-1.96) and 0.91 (0.39-2.14) for subgroups with weight change of < or =0, 0-10, 10-20 and >20 lbs, respectively. There was no significant association between diabetes risk and consumption of instant-caffeinated coffee, instant-decaffeinated coffee or herbal tea. Caffeine intake appeared to explain some, but not all, of the diabetes-risk reduction and weight change.
The negative relationship between diabetes risk and consumption of ground coffee and regular tea, observed for all NHEFS subjects, actually only applied to nonelderly adults who had previously lost weight.
评估体重变化对咖啡和茶的摄入量与糖尿病风险之间关系的影响。
前瞻性队列研究，使用首次全国健康与营养检查调查流行病学随访研究的数据。在8.4年的随访期间，对301例自我报告的糖尿病病例和8例有记录的糖尿病死亡病例进行了生存分析。
共纳入7006名年龄在32 - 88岁之间且无糖尿病报告史的受试者。
对于所有受试者而言，基线时含咖啡因咖啡粉和咖啡因摄入量增加后，随访期间糖尿病风险降低。年龄与咖啡因摄入量（P = 0.02）和含咖啡因咖啡粉摄入量（P = 0.03）之间存在显著的统计学交互作用。年龄分层分析表明，糖尿病风险降低仅适用于年龄≤60岁的受试者，对于他们而言，脱咖啡因咖啡粉和常规茶的摄入量增加也能降低糖尿病风险。含咖啡因咖啡粉、脱咖啡因咖啡粉和常规茶摄入量每天增加2杯的多变量风险比（HR）及95%置信区间分别为0.86（0.75 - 0.99）、0.58（0.34 - 0.99）和0.77（0.59 - 1.00）。糖尿病风险与摄入量呈剂量反应负相关。年龄≤60岁的受试者，既往体重变化与饮料摄入量之间存在很强的统计学交互作用。进一步分析表明，糖尿病风险降低仅适用于体重减轻的人群，且糖尿病风险与体重变化呈正剂量反应关系。例如，脱咖啡因咖啡粉摄入量＞0杯/天与0杯/天相比，体重变化≤0、0 - 10、10 - 20和＞20磅亚组的多变量HR及95%置信区间分别为0.17（0.04 - 0.74）、0.52（0.19 - 1.42）、0.77（0.30 - 1.96）和0.91（0.39 - 2.14）。糖尿病风险与速溶含咖啡因咖啡、速溶脱咖啡因咖啡或花草茶的摄入量之间无显著关联。咖啡因摄入量似乎可以解释部分但不是全部的糖尿病风险降低和体重变化。
在所有全国健康与营养检查调查研究受试者中观察到的糖尿病风险与咖啡粉和常规茶摄入量之间的负相关关系，实际上仅适用于既往体重减轻的非老年成年人。
