Sex differences in progression to mild cognitive impairment and dementia in Parkinson's disease

• Published in: Parkinsonism & related disorders Vol. 50; pp. 29 - 36
• Main Authors: Cholerton, Brenna, Johnson, Catherine O., Fish, Brian, Quinn, Joseph F., Chung, Kathryn A., Peterson-Hiller, Amie L., Rosenthal, Liana S., Dawson, Ted M., Albert, Marilyn S., Hu, Shu-Ching, Mata, Ignacio F., Leverenz, James B., Poston, Kathleen L., Montine, Thomas J., Zabetian, Cyrus P., Edwards, Karen L.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.05.2018
• Subjects: Adult; Aged; Aged, 80 and over; Cognition; Cognitive Dysfunction - etiology; Cognitive Dysfunction - physiopathology; Dementia; Dementia - etiology; Dementia - physiopathology; Disease Progression; Female; Humans; Longitudinal Studies; Male; Middle Aged; Mild cognitive impairment; Parkinson Disease - complications; Parkinson Disease - physiopathology; Parkinson's disease; Sex Characteristics; Sex differences; Sex Factors; Sex differences; Cognition; Parkinson's disease; Mild cognitive impairment; Dementia
• ISSN: 1353-8020; 1873-5126
• DOI: 10.1016/j.parkreldis.2018.02.007

Identification of factors associated with progression of cognitive symptoms in Parkinson's disease (PD) is important for treatment planning, clinical care, and design of future clinical trials. The current study sought to identify whether prediction of cognitive progression is aided by examining baseline cognitive features, and whether this differs according to stage of cognitive disease. Participants with PD in the Pacific Udall Center Clinical Consortium who had longitudinal data available and were nondemented at baseline were included in the study (n = 418). Logistic and Cox regression models were utilized to examine the relationship between cognitive, demographic, and clinical variables with risk and time to progression from no cognitive impairment to mild cognitive impairment (PD-MCI) or dementia (PDD), and from PD-MCI to PDD. Processing speed (OR = 1.05, p = 0.009) and working memory (OR = 1.01, p = 0.03) were associated with conversion to PDD among those with PD-MCI at baseline, over and above demographic variables. Conversely, the primary predictive factor in the transition from no cognitive impairment to PD-MCI or PDD was male sex (OR = 4.47, p = 0.004), and males progressed more rapidly than females (p = 0.01). Further, among females with shorter disease duration, progression was slower than for their male counterparts, and poor baseline performance on semantic verbal fluency was associated with shorter time to cognitive impairment in females but not in males. This study provides evidence for sex differences in the progression to cognitive impairment in PD, while specific cognitive features become more important indicators of progression with impending conversion to PDD. •Determining predictors of cognitive impairment in PD will aid in treatment planning andclinical trial design.•Specific cognitive test performance predicts conversion to dementia but not to mild cognitive impairment in patients with PD.•Male sex is an important predictor of early cognitive decline; females have slower progression to cognitive impairmentͅ.