Department of Preventive Medicine and Public Health, School of Medicine, University of Málaga, Málaga, Spain.
Department of Legal Medicine, Toxicology, and Physical Anthropology, School of Medicine, University of Granada, Granada, Spain.
Clin Nutr. 2021 Feb;40(2):496-504. doi: 10.1016/j.clnu.2020.05.044. Epub 2020 Jun 12.
BACKGROUND & AIMS: Epidemiological data on iron status and cardiovascular disease (CVD) are still controversial. The aim of this study was to determine whether low serum iron (SI) levels are associated with an increased odds of first CVD event in a population at high cardiovascular risk.
Case-control study design nested within the "PREvención con DIeta MEDiterránea" (PREDIMED) trial. A total of 207 participants diagnosed with CVD (myocardial infarction, stroke or cardiovascular death) during follow-up period (2003-2010) were matched by sex, age and intervention group to 436 controls by incidence density sampling. Median time between serum sample collection and subsequent CVD event occurrence was 0.94 years. Inductively coupled plasma mass spectrometry analysis was used to determine SI levels. In-person interviews, medical record reviews, and validated questionnaires were used to assess covariates. Multivariable-adjusted odds ratios (ORs) of CVD were calculated with conditional logistic regression.
Mean SI levels were higher in men than in women (1224.0 μg/L vs. 1093.8 μg/L; p < 0.001). Among women, but not in men, the mean SI concentration was lower in cases than in controls (1008.5 μg/L vs. 1132.9 μg/L; p = 0.030). There was a gradual decrease in the multivariable-adjusted ORs of CVD with increasing SI levels (highest vs. lowest quartile: OR = 0.55, 95% CI: 0.32-0.93; p = 0.020). This inverse relationship was more pronounced among women (highest vs. lowest quartile: OR = 0.15, 95% CI: 0.03-0.69; p = 0.011).
The present findings are consistent with previously reported inverse associations between SI and CVD. SI levels as an independent marker of short-term cardiovascular risk may be useful for risk assessment in older populations.
www.controlled-trials.com; International Standard Randomized Controlled Trial Number (ISRCTN): 35,739,639. Registered 5 October 2005. Retrospectively registered.
关于铁状态与心血管疾病（CVD）的流行病学数据仍存在争议。本研究旨在确定在心血管疾病高危人群中，低血清铁（SI）水平是否与首次 CVD 事件的发生风险增加相关。
病例对照研究设计，嵌套于“地中海饮食预防（PREDIMED）”试验中。共有 207 名参与者在随访期间（2003-2010 年）被诊断为 CVD（心肌梗死、卒中和心血管死亡），按照性别、年龄和干预组，通过发生率密度抽样法匹配了 436 名对照。在血清样本采集和随后的 CVD 事件发生之间的中位时间为 0.94 年。采用电感耦合等离子体质谱法分析来确定 SI 水平。通过面对面访谈、病历审查和经过验证的问卷调查来评估协变量。采用条件逻辑回归计算 CVD 的多变量调整比值比（OR）。
男性的平均 SI 水平高于女性（1224.0μg/L 比 1093.8μg/L；p<0.001）。在女性中，但在男性中，病例组的平均 SI 浓度低于对照组（1008.5μg/L 比 1132.9μg/L；p=0.030）。随着 SI 水平的升高，多变量调整后的 CVD OR 值逐渐降低（最高四分位数比最低四分位数：OR=0.55，95%CI：0.32-0.93；p=0.020）。这种负相关在女性中更为明显（最高四分位数比最低四分位数：OR=0.15，95%CI：0.03-0.69；p=0.011）。
本研究结果与之前报道的 SI 与 CVD 之间的负相关一致。SI 水平作为短期心血管风险的独立标志物，可能有助于评估老年人群的风险。
www.controlled-trials.com；国际标准随机对照试验编号（ISRCTN）：35,739,639。2005 年 10 月 5 日注册。回顾性注册。
