Open AccessSerum IGF-1 is associated with cognitive functions in early, drug-naïve Parkinson’s disease
Author(s) -
Marina Picillo,
Rosario Pivonello,
Gabriella Santangelo,
Claudia Pivonello,
Riccardo Savastano,
Renata S. Auriemma,
Marianna Amboni,
Sara Scannapieco,
Angela Pierro,
Annamaria Colao,
Paolo Barone,
Maria Teresa Pellecchia
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0186508
Subject(s) - dementia , medicine , verbal fluency test , cohort , neuropsychology , cognitive decline , parkinson's disease , quartile , verbal memory , trail making test , cognition , cognitive reserve , effects of sleep deprivation on cognitive performance , oncology , disease , psychiatry , confidence interval
Objective Cognitive deficits are common in Parkinson’s disease (PD) since the early stages and many patients eventually develop dementia. Yet, occurrence of dementia in PD is unpredictable. Evidence supports the hypothesis that insulin-like growth factor-1 (IGF-1) is involved in cognitive deficits. Our aim was to evaluate the relationship between serum IGF-1 levels and neuropsychological scores in a large cohort of drug-naïve PD patients during the earliest stages of the disease. Methods Serum IGF-1 levels were determined in 405 early, drug-naïve PD patients and 191 healthy controls (HC) enrolled in the Parkinson’s Progression Markers Initiative (PPMI). The association between serum IGF-1 levels and neuropsychological scores was evaluated with linear regression analysis. Results IGF-1 levels were similar in PD and HC. In PD patients the lowest IGF-1 quartile was a predictor of lower performances at the Semantic Fluency task (β = -3.46, 95%CI: -5.87 to -1.01, p = 0.005), the Symbol Digit Modalities Score (β = -2.09, 95%CI: -4.02 to -0.15, p = 0.034), and Hopkins Verbal Learning Test Retention (β = -0.05, 95%CI: -0.09 to -0.009, p = 0.019). Conclusions Lower serum IGF-1 levels are associated to poor performances in cognitive tasks assessing executive function, attention and verbal memory in a large cohort of early PD patients. Follow-up studies are warranted to assess if IGF-1 is related to the development of dementia in PD.