GDNF and normal pressure hydrocephalus: This technique was utilized to explore the causal impact of various neurotrophins-such as BDNF, nerve growth factor (NGF), neurotrophin-3 (NT-3), NT-4, ciliary neurotrophic factor (CNTF), and glial cell line-derived neurotrophic factor (GDNF)-on the development or progression of NPH.<h4>Methods</h4>To investigate the causal relationship between five neurotrophin subtypes and NPH, we designed a two-sample Mendelian randomization (MR) study using comprehensive genome-wide association study (GWAS) data.