Department of Health Psychology, Faculty of Health Science, University of Alicante, Spain.
Department of Health Psychology, Faculty of Health Science, University of Alicante, Spain.
Sleep Med Rev. 2021 Aug;58:101437. doi: 10.1016/j.smrv.2021.101437. Epub 2021 Jan 21.
Twin studies have consistently found that genetic factors explain a substantial proportion of the variance for insomnia. However, studies vary widely in their heritability estimates. Therefore, this meta-analysis aimed to: 1) Estimate the mean heritability of insomnia; 2) Assess heterogeneity among twin studies of insomnia; and 3) Search and analyse characteristics of the studies (moderator variables) that may explain heterogeneity among estimates. For this purpose, separate meta-analyses were carried out for MZ and DZ correlations and for heritability estimates by assuming random-effects models. Thirteen independent samples were included in this meta-analysis. The heterogeneity index for heritability estimates was significant in both best fitting models (I = 98.77, P < .0001) and full models (I = 97.80, P < .0001). MZ correlations were higher (0.37; 95%CI: 0.31,.43) than DZ correlations (0.15; 95%CI: 0.12,.18). A mean heritability of 0.39 (95%CI: 0.32,.44) was found for insomnia. These results highlight the role of genetic factors in explaining differences among the population on insomnia and Emphasize heterogeneity among studies. Further research is needed to identify variables that could explain this heterogeneity.
双生子研究一直发现，遗传因素解释了失眠症变异的很大一部分。然而，研究在其遗传率估计值上存在很大差异。因此，本荟萃分析旨在：1）估计失眠症的平均遗传率；2）评估失眠症双胞胎研究之间的异质性；3）搜索和分析可能解释估计值异质性的研究特征（调节变量）。为此，分别进行了 MZ 和 DZ 相关性以及假设随机效应模型的遗传率估计的荟萃分析。这项荟萃分析共纳入了 13 个独立样本。在最佳拟合模型（I=98.77，P<.0001）和全模型（I=97.80，P<.0001）中，遗传率估计的异质性指数均显著。MZ 相关性（0.37；95%CI：0.31，0.43）高于 DZ 相关性（0.15；95%CI：0.12，0.18）。发现失眠症的遗传率为 0.39（95%CI：0.32，0.44）。这些结果强调了遗传因素在解释人群中失眠症差异方面的作用，并强调了研究之间的异质性。需要进一步研究以确定可解释这种异质性的变量。
