School of Public Health, Lanzhou University, Lanzhou, Gansu, China.
Second Clinical College, Lanzhou University, Lanzhou, Gansu, China.
BMJ Open. 2022 May 3;12(5):e049516. doi: 10.1136/bmjopen-2021-049516.
Adverse health effects of fine particles (particulate matter) have been well documented by a series of studies. However, evidences on the impacts of black carbon (BC) or elemental carbon (EC) on health are limited. The objectives were (1) to explored the effects of BC and EC on cardiovascular and respiratory morbidity and mortality, and (2) to verified the reliability of the meta-analysis by drawing p value plots.
The systematic review and meta-analysis using adapted Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach and p value plots approach.
PubMed, Embase and Web of Science were searched from inception to 19 July 2021.
Time series, case cross-over and cohort studies that evaluated the associations between BC/EC on cardiovascular or respiratory morbidity or mortality were included.
Two reviewers independently selected studies, extracted data and assessed risk of bias. Outcomes were analysed via a random effects model and reported as relative risk (RR) with 95% CI. The certainty of evidences was assessed by adapted GRADE. The reliabilities of meta-analyses were analysed by p value plots.
Seventy studies met our inclusion criteria. (1) Short-term exposure to BC/EC was associated with 1.6% (95% CI 0.4% to 2.8%) increase in cardiovascular diseases per 1 µg/m in the elderly; (2) Long-term exposure to BC/EC was associated with 6.8% (95% CI 0.4% to 13.5%) increase in cardiovascular diseases and (3) The p value plot indicated that the association between BC/EC and respiratory diseases was consistent with randomness.
Both short-term and long-term exposures to BC/EC were related with cardiovascular diseases. However, the impact of BC/EC on respiratory diseases did not present consistent evidence and further investigations are required.
CRD42020186244.
一系列研究充分证明了细颗粒物（颗粒物）对健康的不良影响。然而，关于黑碳（BC）或元素碳（EC）对健康影响的证据有限。本研究的目的是：（1）探讨 BC 和 EC 对心血管和呼吸道发病率和死亡率的影响；（2）通过绘制 p 值图来验证荟萃分析的可靠性。
采用改良的推荐评估、制定和评价（GRADE）方法和 p 值图方法进行系统评价和荟萃分析。
从建立至 2021 年 7 月 19 日，检索了 PubMed、Embase 和 Web of Science 数据库。
包括时间序列、病例交叉和队列研究，这些研究评估了 BC/EC 与心血管或呼吸道发病率或死亡率之间的关联。
两位审查员独立选择研究、提取数据并评估偏倚风险。使用随机效应模型分析结果，并报告相对风险（RR）及其 95%置信区间（CI）。采用改良的 GRADE 方法评估证据的确定性。通过 p 值图分析荟萃分析的可靠性。
70 项研究符合纳入标准。（1）短期暴露于 BC/EC 与老年人每增加 1 µg/m 心血管疾病增加 1.6%（95%CI 0.4%至 2.8%）有关；（2）长期暴露于 BC/EC 与心血管疾病增加 6.8%（95%CI 0.4%至 13.5%）有关；（3）p 值图表明 BC/EC 与呼吸道疾病之间的关联与随机性一致。
BC/EC 的短期和长期暴露均与心血管疾病有关。然而，BC/EC 对呼吸道疾病的影响没有一致的证据，需要进一步研究。
CRD42020186244。
