Chen Jiasi, Qin Jingmin, He Qinghua, Zou Zhiling
Faculty of Psychology, Southwest University, Chongqing, China.
Front Psychiatry. 2020 Jun 26;11:598. doi: 10.3389/fpsyt.2020.00598. eCollection 2020.
Substance addiction and food addiction are significant social problems worldwide. In previous studies of substance addiction, transcranial direct current stimulation (tDCS) has been used to influence craving of substance or food. However, the reported effects are not always consistent due to inconsistent experimental settings. The way modulators influence the effect of tDCS on substance addiction is worth exploring. This meta-analysis was conducted to estimate the effect size of tDCS on substance and food craving and to investigate the influence of potential modulators. We systemically identified and reviewed studies on substance/food craving using tDCS that were published between January 2008 to January 2020. A total of 32 eligible studies were identified. Hedges' g was computed as an indicator of the effect of tDCS and some potential moderators (substance type, stimulation sites, current intensities, number of sessions, duration of stimulation, and study design) were examined using subgroup analysis. Random effects analysis revealed a total medium effect size [Hedges' = 0.536, 95% confidence interval (CI): 0.389-0.683, after adjusting Hedges' = 0.416, 95% CI: 0.262-0.570] preferring active over sham stimulation to reduce craving. A significant difference was observed between the number of sessions (repeated stimulation was better than single stimulation). The duration of stimulation may have a positive influence on the effects of tDCS. No other significant differences were found in other subgroups analysis. In conclusion, our results provided evidence that tDCS can be an effective way to reduce craving of substance or food, and longer multiple stimulus durations in all can more effectively reduce craving; however, the influences of modulators still need be to be examined in depth in future.
物质成瘾和食物成瘾是全球范围内的重大社会问题。在以往关于物质成瘾的研究中，经颅直流电刺激（tDCS）已被用于影响对物质或食物的渴望。然而，由于实验设置不一致，所报道的效果并不总是一致的。调节剂影响tDCS对物质成瘾效果的方式值得探索。本荟萃分析旨在估计tDCS对物质和食物渴望的效应大小，并研究潜在调节剂的影响。我们系统地识别和回顾了2008年1月至2020年1月期间发表的使用tDCS治疗物质/食物渴望的研究。共识别出32项符合条件的研究。计算了Hedges' g作为tDCS效果的指标，并使用亚组分析检查了一些潜在的调节因素（物质类型、刺激部位、电流强度、疗程数、刺激持续时间和研究设计）。随机效应分析显示，总体效应大小为中等[Hedges' g = 0.536，95%置信区间（CI）：0.389 - 0.683，调整后Hedges' g = 0.416，95% CI：0.262 - 0.570]，表明与假刺激相比，主动刺激更能减少渴望。疗程数之间存在显著差异（重复刺激优于单次刺激）。刺激持续时间可能对tDCS的效果有积极影响。在其他亚组分析中未发现其他显著差异。总之，我们的结果提供了证据，表明tDCS可以是减少对物质或食物渴望的有效方法，并且总体上较长的多次刺激持续时间可以更有效地减少渴望；然而，调节剂的影响仍需要在未来进行深入研究。
