Abstract：
OBJECTIVE: In populations of black African ancestry (BA), a paradox exists whereby lower visceral adipose tissue is found despite their high risk for type 2 diabetes (T2D). This systematic review investigates ethnic differences in other ectopic fat depots (intrahepatic lipid: IHL; intramyocellular lipid: IMCL and intrapancreatic lipid; IPL) to help contextualise their potential contribution to T2D risk.
METHODS: A systematic literature search was performed in December 2020 to identify studies reporting at least one ectopic fat comparison between BA and one/more other ethnicity. For IHL, a meta-analysis was carried out with studies considered comparable based on the method of measurement.
RESULTS: Twenty-eight studies were included (IHL: n = 20; IMCL: n = 8; IPL: n = 4). Meta-analysis of 11 studies investigating IHL revealed that it was lower in BA populations vs pooled ethnic comparators (MD -1.35%, 95% CI -1.55 to -1.16, I2 = 85%, P < 0.00001), white European ancestry (MD -0.94%, 95% CI -1.17 to -0.70, I2 = 79%, P < 0.00001), Hispanic ancestry (MD -2.06%, 95% CI -2.49 to -1.63, I2 = 81%, P < 0.00001) and South Asian ancestry comparators (MD -1.92%, 95% CI -3.26 to -0.57, I2 = 78%, P = 0.005). However, heterogeneity was high in all analyses. Most studies found no significant differences in IMCL between BA and WE. Few studies investigated IPL, however, indicated that IPL is lower in BA compared to WE and HIS.
CONCLUSIONS: The discordance between ectopic fat and greater risk for T2D in BA populations raises questions around its contribution to T2D pathophysiology in BA.
METHODS: A systematic literature search was performed in December 2020 to identify studies reporting at least one ectopic fat comparison between BA and one/more other ethnicity. For IHL, a meta-analysis was carried out with studies considered comparable based on the method of measurement.
RESULTS: Twenty-eight studies were included (IHL: n = 20; IMCL: n = 8; IPL: n = 4). Meta-analysis of 11 studies investigating IHL revealed that it was lower in BA populations vs pooled ethnic comparators (MD -1.35%, 95% CI -1.55 to -1.16, I2 = 85%, P < 0.00001), white European ancestry (MD -0.94%, 95% CI -1.17 to -0.70, I2 = 79%, P < 0.00001), Hispanic ancestry (MD -2.06%, 95% CI -2.49 to -1.63, I2 = 81%, P < 0.00001) and South Asian ancestry comparators (MD -1.92%, 95% CI -3.26 to -0.57, I2 = 78%, P = 0.005). However, heterogeneity was high in all analyses. Most studies found no significant differences in IMCL between BA and WE. Few studies investigated IPL, however, indicated that IPL is lower in BA compared to WE and HIS.
CONCLUSIONS: The discordance between ectopic fat and greater risk for T2D in BA populations raises questions around its contribution to T2D pathophysiology in BA.
摘要：
目标：在非洲黑人血统（BA）的人群中，存在一个自相矛盾的现象,即发现下内脏脂肪组织,尽管它们患2型糖尿病(T2D)的风险很高.本系统综述调查了其他异位脂肪库（肝内脂质：IHL；肌内脂质：IMCL和胰腺内脂质；IPL）的种族差异，以帮助了解其对T2D风险的潜在贡献。
方法：于2020年12月进行了系统的文献检索，以确定报告BA与一个/多个其他种族之间至少有一项异位脂肪比较的研究。对于国际人道主义法，我们对基于测量方法认为具有可比性的研究进行了荟萃分析.
结果：纳入28项研究（IHL：n=20；IMCL：n=8；IPL：n=4）。对调查IHL的11项研究进行的荟萃分析显示，与合并的种族比较者相比，BA人群中的IHL较低（MD-1.35％，95%CI-1.55至-1.16，I2=85%，P<0.00001),欧洲白人血统（MD-0.94%，95%CI-1.17至-0.70，I2=79%，P<0.00001),西班牙裔血统（MD-2.06%，95%CI-2.49至-1.63，I2=81%，P<0.00001)和南亚血统比较者(MD-1.92%，95%CI-3.26至-0.57，I2=78%，P=0.005)。然而,所有分析的异质性都很高.大多数研究发现BA和WE之间的IMCL没有显着差异。很少有研究调查IPL，然而,表明与WE和HIS相比，BA的IPL较低。
结论：BA人群中异位脂肪与T2D风险之间的不一致引发了关于其对BA中T2D病理生理学的贡献的疑问。
方法：于2020年12月进行了系统的文献检索，以确定报告BA与一个/多个其他种族之间至少有一项异位脂肪比较的研究。对于国际人道主义法，我们对基于测量方法认为具有可比性的研究进行了荟萃分析.
结果：纳入28项研究（IHL：n=20；IMCL：n=8；IPL：n=4）。对调查IHL的11项研究进行的荟萃分析显示，与合并的种族比较者相比，BA人群中的IHL较低（MD-1.35％，95%CI-1.55至-1.16，I2=85%，P<0.00001),欧洲白人血统（MD-0.94%，95%CI-1.17至-0.70，I2=79%，P<0.00001),西班牙裔血统（MD-2.06%，95%CI-2.49至-1.63，I2=81%，P<0.00001)和南亚血统比较者(MD-1.92%，95%CI-3.26至-0.57，I2=78%，P=0.005)。然而,所有分析的异质性都很高.大多数研究发现BA和WE之间的IMCL没有显着差异。很少有研究调查IPL，然而,表明与WE和HIS相比，BA的IPL较低。
结论：BA人群中异位脂肪与T2D风险之间的不一致引发了关于其对BA中T2D病理生理学的贡献的疑问。
