School of Pharmacy, China Medical University, Shenyang, China.
Department of Pharmacy, Shengjing Hospital of China Medical University, Shenyang, China.
BMC Geriatr. 2023 Mar 30;23(1):195. doi: 10.1186/s12877-023-03900-7.
Given their potent antioxidation properties, carotenoids play a role in delaying and preventing dementia and mild cognitive impairment (MCI). However, observational studies have found inconsistent results regarding the associations between blood carotenoid levels and the risk of dementia and MCI. We conducted this systematic review and meta-analysis to investigate the relationship between blood carotenoid levels and the risk of dementia and MCI.
A systematic search was performed in the Web of Science, PubMed, Embase, and Cochrane Library electronic databases to retrieve relevant English articles published from their inception until February 23, 2023. Study quality was assessed by the Newcastle-Ottawa scale. Standardized mean differences (SMDs) and 95% confidence intervals (CIs) were pooled using random-effect meta-analyses. Ultimately, 23 studies (n = 6610) involving 1422 patients with dementia, 435 patients with MCI, and 4753 controls were included.
Our meta-analysis showed that patients with dementia had lower blood lycopene (SMD: -0.521; 95%CI: -0.741, -0.301), α-carotene (SMD: -0.489; 95%CI: -0.697, -0.281), β-carotene (SMD: -0.476; 95%CI: -0.784, -0.168), lutein (SMD: -0.516; 95%CI: -0.753, -0.279), zeaxanthin (SMD: -0.571; 95%CI: -0.910, -0.232) and β-cryptoxanthin (SMD: -0.617; 95%CI: -0.953, -0.281) than the controls. Our results indicated that blood carotenoid levels were significantly lower in patients with dementia than in controls, despite high heterogeneity across the studies. Owing to insufficient data, we did not observe a similar and stable relationship between blood carotenoid levels and MCI.
Our meta-analysis indicated that lower blood carotenoid levels may be a risk factor for dementia and MCI.
类胡萝卜素具有很强的抗氧化作用，因此在延缓和预防痴呆症和轻度认知障碍（MCI）方面发挥作用。然而，观察性研究发现血液类胡萝卜素水平与痴呆症和 MCI 风险之间的关联结果不一致。我们进行了这项系统评价和荟萃分析，以调查血液类胡萝卜素水平与痴呆症和 MCI 风险之间的关系。
我们在 Web of Science、PubMed、Embase 和 Cochrane Library 电子数据库中进行了系统搜索，以检索自成立以来至 2023 年 2 月 23 日发表的相关英文文章。使用纽卡斯尔-渥太华量表评估研究质量。使用随机效应荟萃分析汇总标准化均数差值（SMD）和 95%置信区间（CI）。最终纳入 23 项研究（n=6610），包括 1422 例痴呆症患者、435 例 MCI 患者和 4753 例对照。
我们的荟萃分析表明，痴呆症患者的血液番茄红素（SMD：-0.521；95%CI：-0.741，-0.301）、α-胡萝卜素（SMD：-0.489；95%CI：-0.697，-0.281）、β-胡萝卜素（SMD：-0.476；95%CI：-0.784，-0.168）、叶黄素（SMD：-0.516；95%CI：-0.753，-0.279）、玉米黄质（SMD：-0.571；95%CI：-0.910，-0.232）和β-隐黄质（SMD：-0.617；95%CI：-0.953，-0.281）水平低于对照组。尽管研究之间存在高度异质性，但我们的结果表明，痴呆症患者的血液类胡萝卜素水平明显低于对照组。由于数据不足，我们没有观察到血液类胡萝卜素水平与 MCI 之间存在类似且稳定的关系。
我们的荟萃分析表明，较低的血液类胡萝卜素水平可能是痴呆症和 MCI 的危险因素。
