IGF1 and Parkinson disease: The presence of medical confounders showed no significant effect on IGF-1 levels, neither in the overall nor in separate diagnostic groups (p > .1), individuals with these factors numerically showed lower IGF-1 levels compared with those without these factors (PD with: 116 ± 26, without: 125 ± 27; HC with: 100 ± 12, without: 110 ± 26 ng/mL).