We analyzed longitudinal data from 726 individuals with typical PD, including 22 carriers of severe <i>GBA1</i> variants and 47 carriers of PD-risk <i>GBA1</i> variants.<h4>Results</h4>The findings were not significant after adjusting for Bonferroni correction; however, linear mixed models analyses showed that at a nominal significance level of 5%, carriers of PD-risk or severe variants were associated with faster cognitive decline compared to non-carriers. Here, GBA1 is linked to Parkinson disease.