Abstract:
Previous observational studies revealed controversy about the effect of circulating antioxidants on risk of alopecia. In the present study, we investigated the causal relationships between diet-derived circulating antioxidants and 2 non-scarring alopecia using Mendelian randomization (MR). Instrumental variables for antioxidants (lycopene, retinol, ascorbate, β-carotene, α-tocopherol, and γ-tocopherol) were selected from published studies. Data for alopecia areata (AA) and androgenetic alopecia (AGA) was obtained from the FinnGen study project (R9 released in 2023), including 195 cases and 201,019 controls for AGA and 682 cases and 361,140 controls for AA. We used the inverse variance weighted method as the primary MR method. Three additional methods were used as sensitivity analysis to validate the robustness of the results. We found a causal relationship between absolute β-carotene levels and AGA risk (P = .039), but not with AA (P = .283). The results of Wald ratio showed a protective effect of absolute β-carotene levels against AGA, with per 0.1 ln-transformed β-carotene being associated with a 76% lower risk of AGA (OR: 0.24, 95% CI: 0.06-0.93). Based on the fixed effects inverse variance weighting results, we found that α-tocopherol was protective against both AGA (P = .026) and AA (P = .018). For each unit increase in α-tocopherol, the effects of change in AGA and AA were 0.02 (95% CI: 0.00-0.61) and 0.10 (95% CI: 0.01-0.67), respectively. The results did not reveal any other causal relationships. Our study identified 3 causal associations of antioxidants with the risk of non-scarring alopecia. These results provide new insights into the prevention of non-scarring alopecia through diet.
摘要:
先前的观察性研究揭示了关于循环抗氧化剂对脱发风险的影响的争议。在本研究中,我们使用孟德尔随机化(MR)研究了饮食来源的循环抗氧化剂与2种非瘢痕性脱发之间的因果关系.抗氧化剂的仪器变量(番茄红素,视黄醇,抗坏血酸,β-胡萝卜素,α-生育酚,和γ-生育酚)从已发表的研究中选择。斑秃(AA)和雄激素性脱发(AGA)的数据来自FinnGen研究项目(R9于2023年发布),包括195例AGA和201,019例对照,以及682例AA和361,140例对照。我们使用逆方差加权方法作为主要的MR方法。另外三种方法被用作灵敏度分析以验证结果的稳健性。我们发现绝对β-胡萝卜素水平与AGA风险之间存在因果关系(P=0.039),但不是AA(P=.283)。Wald比值结果显示绝对β-胡萝卜素水平对AGA有保护作用,每0.1ln转化的β-胡萝卜素与AGA风险降低76%相关(OR:0.24,95%CI:0.06-0.93)。根据固定效应方差倒数加权结果,我们发现α-生育酚对AGA(P=0.026)和AA(P=0.018)均具有保护作用。对于α-生育酚每增加一个单位,AGA和AA变化的影响分别为0.02(95%CI:0.00-0.61)和0.10(95%CI:0.01-0.67),分别。结果没有揭示任何其他因果关系。我们的研究确定了抗氧化剂与非瘢痕性脱发风险的3个因果关系。这些结果为通过饮食预防非瘢痕性脱发提供了新的见解。