Significant impairments found to be frequent
A sizeable study of 54 HSPers, including 36 with SPG4, using five different tests for cognitive assessment, has found that cognitive abnormalities occur frequently in both pure and complicated forms of HSP.
People with SPG4 had worse performance on four of the five tests when compared to the control group (no HSP). The cognitive changes identified were not compatible with dementia and included performing poorly on memory, attention and executive functions.
People with SPG5 similarly scored lower on memory and executive functions and those with SPG7 performed poorly on memory tasks.
All with SPG11 had markedly altered cognitive functions across all tests.
Background: Little is known about the cognitive profile of Hereditary Spastic Paraplegias (HSP), where most scientific attention has been given to motor features related to corticospinal tract degeneration.
Objectives: We aimed to perform a broad characterization of the cognitive functions of patients with pure and complicated HSP as well as to determine the frequency of abnormal cognitive performances in the studied subtypes.
Methods: A two-center cross-sectional case-control study was performed. All individuals underwent cognitive assessment through screening tests (Mini Mental State Examination-MEEM and Montreal Cognitive Assessment-MOCA) and tests to assess specific cognitive functions (Verbal fluency with phonological restriction-FAS; Verbal categorical fluency-FAS-cat and Rey’s Verbal Auditory Learning Test -RAVLT).
Results: Fifty four patients with genetically confirmed HSP diagnosis, 36 with spastic paraplegia type 4 (SPG4), 5 SPG11, 4 SPG5, 4 cerebrotendinous xanthomatosis (CTX), 3 SPG7 and 2 SPG3A, and 10 healthy, unrelated control subjects, with similar age, sex, and education participated in the study. SPG4 patients had worse performances in MOCA, FAS, FAS-cat, and RAVLT when compared to controls.
Most SPG4 patients presented cognitive changes not compatible with dementia, performing poorly in memory, attention and executive functions. SPG5 patients scored lower in executive functions and memory, and SPG7 patients performed poorly on memory tasks.
All evaluated cognitive functions were markedly altered in CTX and SPG11 patients.
Conclusions: Cognitive abnormalities are frequent in HSP, being more severe in complicated forms. However, cognitive impairments of pure HSPs might impact patients’ lives, decreasing families’ socioeconomic status and contributing to the overall disease burden.
SOURCE: Front Neurol. 2019 May 24;10:508. doi: 10.3389/fneur.2019.00508. eCollection 2019. PMID: 31231294
Are Cognitive Changes in Hereditary Spastic Paraplegias Restricted to Complicated Forms?
1 Graduate Program in Medicine: Medical Sciences, Universidade Federal Rio Grande do Sul, Porto Alegre, Brazil.
2 Medical Genetics Service, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil.
3 Postgraduate Program in Health Sciences, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil.
4 Graduate Program in Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
5 Graduate program in Medical Physiopathology, School of Medical Science, Universidade Estadual de Campinas, Campinas, Brazil.
6 Graduate program in Gastroenterology and Hepatology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
7 Unit of Laboratorial Research/Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.
8 Department of Neurology, School of Medical Science, Universidade Estadual de Campinas, Campinas, Brazil.
9 Department of Surgery and Orthopedics, Faculdade de Odontologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
10 Department of Internal Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
11 Neurology Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.