Persistent cognitive deficits

Neuroleptic-Induced Neurotoxicity, Brain Damage, Persistent Cognitive Deficits, Dementia, and Psychosis... 

Because of their neurotoxicity, neuroleptics probably worsen any brain disorder. A controlled experiment with rats subjected to traumatic brain injury demonstrated that chronic, high doses of risperidone or haloperidol were detrimental, causing persistent cognitive deficits (Kline et al., 2000). 

A number of the CT scan studies have found a correlation between atrophy and persistent cognitive deficits or frank dementia in these neuroleptic-treated patients (DeMeyer et al., 1984 Famuyiwa et al., 1979 Golden et al., 1980 Johnstone et al., 1976 Lawson et al., 1988). Some of these studies used the Nebraska and Halstead-Reitan batteries, considered among the most sensitive for detecting brain damage and dysfunction. 

Many clinical studies have now confirmed the existence of persistent cognitive deficits and dementia in association with neuroleptic use. However, to some extent, researchers have lost their enthusiasm for demonstrating over and over again that neuroleptics cause cognitive deficits, and textbooks of psychiatry simply do not want to mention it (e.g., Hales et al., 2003). This is reminiscent of the history of research into the brain-damaging effects of shock treatment (chapter 9). When repeated... 

Bartha L, Marksteiner J, Bauer G, Benke T. Persistent cognitive deficits associated with lithium intoxication a neuropsychological case description. Cortex 2002 38(5) 743-52. 

Schneider JS, Tobe EH, Mozley Jr. PD, et al. 1998. Persistent cognitive and motor deficits following acute hydrogen sulphide poisoning. Occup Med 48 255-260. 

As in the case of chronic opiate abuse, few brain morphometric studies of human cannabis abusers have been conducted. However, recent preclinical work has demonstrated that 5 -THC concentrations as low as 0.5 to 1 lM, which are compatible with plasma 5 -THC levels achieved by humans ingesting marijuana, are toxic to hippocampal neurons (Chan et ah, 1998). This hippocampal toxicity may underlie the cognitive deficits observed in chronic marijuana users, which have been shown to persist after abstinence (Pope and Yurgel un-Todd, 1996). 

Cognitive deficits and psychosocial dysfunction are common in the first year in patients who otherwise make a good recovery. They persist for years. In one study, a quarter of previously employed patients had stopped working, and another quarter worked shorter hours or in a position with reduced responsibility (Wermer et al. 2007). Changes in personality included increased irritability and emotionality. Overall, only 25% of those living independently reported a complete absence of psychosocial problems. 

Thyroid hormone is essential for normal development of the human brain (Calvo, 1990 Morreale de Escobar et al. 2000). Numerous factors are involved in controlling the levels of receptor-active thyroid hormone, and disruption of any of these at critical phases of human development can lead to severe and persistent cognitive and motor deficits (Haddow, 1999). 

Epilepsy, the most common acquired chronic neurological disease, occurs in 1% of the human population. Despite treatment with the newest antiepileptic medications, almost one-third of the individuals continue having seizures (Kwan and Brodie, 2000). Many of those with seizure persistence and even some with seizure remittance suffer often from under-appreciated co-morbidities including cognitive deficits and psychopathology such as anxiety, depression, and poor attention. 

Dementia generally involves an impairment in (1) memoiy and other cogntive abilities and (2) social and occupational functioning. The Diagnostic and Statisticai Manuai ofMentai Disorders (DSM-IV) defines dementia as a persistent deficit in memory and at least one other area of cognitive function language, praxis, object recognition, or executive... 

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