Elucidating the relationship between coffee consumption and obsessive-compulsive disorder: A Mendelian randomization study

Abstract Background The relationship between coffee consumption and obsessive-compulsive disorder (OCD) is inconsistent in previous clinical studies and is still in dispute. This study employs a Mendelian randomization approach to examine the causal relationship between coffee consumption and the prevention of OCD in a European population. Methods The summary statistics of coffee consumption (coffee intake, instant coffee intake, and filtered coffee intake) were obtained from the MRC Integrative Epidemiology Unit consortium, UK Biobank (UKB) data and OCD information was obtained from the FinnGen Consortium (1059 patients and 198110 controls). Sensitivity analysis under various model assumptions was carried out using multiple MR approaches to assess the impact of pleiotropy effects and outliers. Results Genetically predicted coffee consumption was associated with a lower risk of OCD in the main analysis (OR 0.332, 95% CI 0.117,0.943, P = 0.038), especially with instant coffee intake (OR = 0.014, 95%CI: 0,0.426, P = 0.014), but not with filter coffee (OR = 1.037, 95%CI: 0.772,1.392, P = 0.810). There was no significant heterogeneity and pleiotropy between the cohorts. The findings were strong and convincing as the results aligned with the previous study. Conclusions Our MR results based on genetic data revealed the potential protective effect of coffee intake and instant coffee intake on OCD, except for filtered coffee intake. Our results demonstrate the usefulness of coffee consumption habits in the diet in preventing OCD. Additional research with OCD sufferers and more reliable SNPs is required. It is also advised that our findings be verified.