Department of Medicine, Duke University, Durham, North Carolina.
Department of Biostatistics, Collaborative Studies Coordinating Center.
J Gerontol A Biol Sci Med Sci. 2015 Feb;70(2):255-61. doi: 10.1093/gerona/glu071. Epub 2014 Jun 3.
We sought to determine the impacts of serum and dietary potassium measures on glucose metabolism and diabetes risk in older adults.
Among participants of the Cardiovascular Health Study, a community-based cohort of older American adults, we examined a) cross-sectional associations between potassium and measures of insulin sensitivity and secretion estimated from oral glucose tolerance tests and b) longitudinal associations of serum and dietary potassium with diabetes risk.
Among 4,754 participants aged ≥65 years at baseline, there were 445 cases of incident diabetes during a median follow-up of 12 years. In multivariate models, baseline serum and dietary potassium were both associated with lower insulin sensitivity and greater insulin secretion. Compared with those with a serum potassium ≥4.5 mEq/L, participants with a serum potassium <4.0mEq/L had an adjusted mean difference in Matsuda insulin sensitivity index of -0.18 (-0.39, 0.02). Compared with those in the highest quartile, participants in the lowest quartile of dietary potassium intake had a corresponding adjusted mean difference in Matsuda insulin sensitivity index of -0.61 (-0.94, -0.29). In multivariate models, neither serum nor dietary potassium intake was associated with long-term diabetes risk.
Although we did not identify serum and dietary potassium as risk factors for incident diabetes in older adults, results from cross-sectional analyses suggest that both may be associated with increased insulin resistance. This relationship with insulin resistance needs to be confirmed, and its importance on diabetes risk, cardiovascular risk, and conditions specific to older adults should be determined as well.
我们旨在确定血清和膳食钾测量值对老年人葡萄糖代谢和糖尿病风险的影响。
在心血管健康研究（一项基于社区的美国老年人队列研究）的参与者中，我们检查了 a）钾与口服葡萄糖耐量试验估计的胰岛素敏感性和分泌的测量值之间的横断面关联，以及 b）血清和膳食钾与糖尿病风险的纵向关联。
在基线时年龄≥65 岁的 4754 名参与者中，中位随访 12 年后有 445 例发生糖尿病。在多变量模型中，基线血清和膳食钾均与较低的胰岛素敏感性和更大的胰岛素分泌相关。与血清钾≥4.5mEq/L 的参与者相比，血清钾<4.0mEq/L 的参与者调整后的平均差异为 Matsuda 胰岛素敏感性指数为-0.18（-0.39，0.02）。与膳食钾摄入量最高四分位的参与者相比，膳食钾摄入量最低四分位的参与者相应的调整后的平均差异为 Matsuda 胰岛素敏感性指数为-0.61（-0.94，-0.29）。在多变量模型中，血清和膳食钾摄入均与长期糖尿病风险无关。
尽管我们没有确定血清和膳食钾是老年人发生糖尿病的危险因素，但横断面分析的结果表明，两者都可能与胰岛素抵抗增加有关。这种与胰岛素抵抗的关系需要得到证实，其对糖尿病风险、心血管风险以及老年人特有的情况的重要性也需要确定。
