Lambros Messinis

Neuropsychological deficits in long-term frequent cannabis users.

The authors examined neuropsychological functioning in 20 long-term (LT), 20 shorter term (ST) heavy frequent cannabis users, and 24 controls after abstinence for ≥24 hours prior to testing. LT users performed significantly worse on verbal memory and psychomotor speed. LT and ST users had a higher proportion of deficits on verbal fluency, verbal memory, attention, and psychomotor speed. Specific cognitive domains appear to deteriorate with increasing years of heavy frequent cannabis use.

Neuropsychological function in Greek patients with chronic hepatitis C

Background: Research has shown that hepatitis C virus (HCV) infection is associated with subclinical neuropsychological deficits in the absence of hepatic encephalopathy.

Prevalence and Incidence of Multiple Sclerosis in Western Greece: A 23-Year Survey

Background: The frequency of multiple sclerosis (MS) in Greece remains speculative, as data from many parts are still lacking. Objective: To estimate trends in MS prevalence and annual incidence in western Greece from January 1, 1984 to December 31, 2006. Methods: Patients were identified from the patient records of the Department of Neurology at Patras University Hospital in Rion-Patras. Only patients with a definite MS diagnosis according to Poser’s criteria and retrospective application of the McDonald’s criteria were included. We calculated age- and sex-specific prevalence rates for patients living in the study area on December 31, 2006. Annual incidence rates were calculated for the period 1984–2006. Results: The crude prevalence rate of definite MS cases increased significantly in 23 years from 10.1/100,000 recorded in northeastern Greece in 1984 to 119.61/100,000 on December 31, 2006 in western Greece for the 780 cases still alive. The mean annual incidence rate increased from 2.71/100,000 recorded during the period 1984–1989 to 10.73/100,000 in the 5-year period of 2002–2006. Conclusion: The prevalence rates were higher than expected, but closer than in previous surveys conducted in Greece to those reported recently in Sicily and Istanbul. These findings place the area in the high-risk zone.

Assessment and rehabilitation of cognitive impairment in multiple sclerosis

Patients with multiple sclerosis (MS) have a substantial risk of cognitive dysfunction, even in the earliest stages of the disease, where there is minimum physical disability. Despite the high prevalence rates and the significant impact of cognitive dysfunction on quality of life in this population, cognitive functions are not routinely assessed due to the high cost and time consumption. This article provides an overview of the current state of knowledge related to cognition in MS and on the optimal approach to neuropsychological assessment of this population. It then focuses on the pharmacological and other treatment options available for MS patients with, or at risk for developing, cognitive impairment. The available immune-modulating agents may reduce the development of new lesions and therefore prevent or minimize the progression of cognitive decline. However, there is currently insufficient evidence concerning the efficiency of symptomatic treatment in MS. There is also currently no optimal non-pharmacological treatment strategy for cognitive decline in MS, as the studies published to date report heterogeneous results. Nevertheless, non-pharmacological treatments such as cognitive rehabilitation may benefit some MS patients. As cognition is increasingly recognized as a major feature of MS, its assessment and rehabilitation will become a greater priority.

Does motor subtype influence neurocognitive performance in Parkinson’s disease without dementia?

The postural instability and gait difficulty (PIGD) motor subtype has been shown to represent a risk factor for development of dementia in Parkinson’s disease. Whether this relationship extends to a more subtle cognitive dysfunction in patients is less clear. Therefore, we administered a battery of selected neuropsychological tests to two groups of non‐demented patients with mild to moderate disease classified either as PIGD or as non‐PIGD subtype and to a group of healthy controls. Groups were matched on potential confounders of neuropsychological performance. No significant differences were revealed between the two groups of patients in the performance of any of the administered neuropsychological tests. However, relative to controls there was a tendency towards a differential pattern of cognitive dysfunction. The PIGD group had slower performance in a test of psychomotor speed and cognitive flexibility, whilst the non‐PIGD group performed worse in measures of verbal learning and visuo‐spatial perception. In conclusion, the PIGD subtype was not associated with more severe cognitive deficits and may to a certain extent share common mechanisms of cognitive dysfunction with non‐PIGD subtypes. Diverse pathological processes however may develop to account for unequal rates of dementia amongst different motor subtypes.

Psychotic features associated with multiple sclerosis

Although once considered rare, several more recent investigations have been published describing psychotic features in multiple sclerosis (MS). The association between the two conditions, however, remains unclear. Large-scale hospital-based, epidemiological and case studies have suggested a relationship between psychosis and MS through demonstrating their higher than chance co-occurrence, their temporal relationship, and their association with particular structural abnormalities in the brain (i.e., periventricular white matter and temporal demyelination). The etiology of psychosis in MS has also not been explained adequately. Regional demyelination and the use of corticosteroids have been implicated, yet their mechanisms of action have not been elucidated. The present review addresses what is known at this point in time regarding the occurrence of psychosis in the context of MS, the data regarding possible etiological factors, and the implications of these data and suggestions regarding diagnosis and treatment. Future research should explore the underlying pathophysiology of psychosis and multiple sclerosis to further our understanding of the central nervous system disease process. This research could help determine the features which would guide clinicians in identifying patients at risk of developing psychosis in the context of MS, as well as propose the optimal pharmacological intervention.

Cognitive Impairment in Relapsing Remitting and Secondary Progressive Multiple Sclerosis Patients: Efficacy of a Computerized Cognitive Screening Battery

Objective. To investigate the pattern of cognitive impairment in relapsing remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS) patients using a computerized battery. Methods. RRMS patients (N = 50), SPMS patients (N = 30), and controls (N = 31) were assessed by Central Nervous System Vital Signs (CNS VS) computerized battery, Trail Making Tests (TMT) A and B, and semantic and phonological verbal fluency tasks. Results. The overall prevalence of cognitive dysfunction was 53.75% (RRMS 38%, SPMS 80%). RRMS patients differed from controls with large effect size on reaction time, medium effect size on TMT A and small on TMT B, phonological verbal fluency, composite memory, psychomotor speed, and cognitive flexibility. SPMS patients differed from controls in all neuropsychological measures (except complex attention) with large effect sizes on TMT A and B, phonological verbal fluency, composite memory, psychomotor speed, reaction time, and cognitive flexibility. Between patient groups, medium effect sizes were present on TMT B and psychomotor speed, while small effect sizes were present on composite memory and processing speed. Conclusion. CNS VS is sensitive in detecting cognitive impairment in RRMS and SPMS patients. Significant impairment in episodic memory, executive function, and processing speed were identified, with gradual increment of the frequency as disease progresses.

Neuropsychological functioning in buprenorphine maintained patients versus abstinent heroin abusers on naltrexone hydrochloride therapy.

Methadone and buprenorphine are among the most widely employed pharmacological treatments currently available for opioid addiction. Cognitive effects of buprenorphine in abstinent heroin abusers are nevertheless far from being understood.

Benton Visual Retention Test performance in normal adults and acute stroke patients: demographic considerations, discriminant validity, and test-retest reliability.

We examined relationships between demographic variables and Benton Visual Retention Test performance in 352 healthy Greek adults, aged 18–84 years. We derived norms for BVRT total number correct and error scores adjusted for variables that contributed significantly to the variance. We also investigated BVRT performance in 28 acute stroke patients M = 6.14 days after insult. Age, education, and IQ, but not gender, were significantly associated with BVRT performance in healthy participants. However, only age contributed significantly to BVRT performance in acute stroke patients. Test–retest reliability was moderate (.782) for number correct and low for number error (.596) scores. Practice effects were noted only for number correct score. The test appears to discriminate adequately between acute stroke patients and matched healthy controls.

Color Trails Test: Normative Data and Criterion Validity for the Greek Adult Population

The Color Trails Test (CTT) was developed as a culturally fair analog of the Trail Making Test. In the present study, normative data for the CTT were developed for the Greek adult population and further the criterion validity of the CTT was examined in two clinical groups (29 Parkinsons disease [PD] and 25 acute stroke patients). The instrument was applied to 163 healthy participants, aged 19-75. Stepwise linear regression analyses revealed a significant influence of age and education level on completion time in both parts of the CTT (increased age and decreased educational level contributed to slower completion times for both parts), whereas gender did not influence time to completion of part B. Further, the CTT appears to discriminate adequately between the performance of PD and acute stroke patients and matched healthy controls.