A case of dementia in a middle aged man following three decades of amphetamine dependence

Abstract

A 48 year old man presented to the outpatient clinic reporting memory decline interfering with his functioning. He would lose his place during tasks; forget appointments, and the names and faces of new and old acquaintances. Symptom commencement was unclear, but had been present for at least two years, first noticed when he ceased methamphetamine use.The patient began smoking amphetamine from age 16. He soon moved to injecting amphetamine and later methamphetamine on a daily basis up to 3 or 4 times a day, for 30 years before ceasing due to incarceration in prison for drug related offences. He had not used psychostimulants for over 2 years. He was also a regular smoker of cannabis. The patient had a history of head injuries from motor vehicle accidents, fights and sporting injuries.He suffered from hemochromatosis, which was well managed by regular venepuncture.On examination, the patient was alert and orientated, and was broadly able to give a coherent history, but lost his place during long anecdotes. On frontal lobe testing he performed poorly on alternating hand sequences, the 'no-go' test and proverb interpretation. There were no frontal release signs. His neurological examination was unremarkable. On further cognitive testing, he scored 75/100 on the Addenbrooke's Cognitive Examination (ACE-R), with significant impairments in memory, verbal fluency and minor impairment in attention and orientation. Other domains were unremarkable. Blood tests including iron studies, metabolic parameters, syphilis serology, HIV and hepatitis screens were negative. CT and MRI of the brain were unremarkable.Methamphetamine (MA) has been shown to be neurotoxic to both dopaminergic and serotonergic neurons in both human, but in particular animal studies. Studies have shown long term neuronal damage in abstinent MA users with significant reductions in basal ganglia and frontal white matter. [1,2] Until recently, the prevailing view was that methamphetamine use, even when the user achieved abstinence, caused a broad range of cognitive deficits, evidenced by deficits on cognitive testing and observed on neuroimaging studies.[3] However a critical review by Hart et al [4] attempted to dispel this view by examining the significance of cognitive deficits and neuroimagining changes in users, suggesting the clinical significance of these findings may be limited because the cognitive functioning had overwhelmingly fallen within the normal range when compared with normative data.Despite neuroanatomical research highlighting selective damage to the medial temporal lobe including cingulate-limbic cortex, the functional cognitive deficits experienced by abstinent chronic MA users has not been well described [3,4] suggest that although cognitive impairment in users may be statistically significant, its clinical relevance, or every day import, is rarely specified. In the case of our patient, his cognitive impairment was clinically significant, functionally impairing and of sufficient degree to merit a diagnosis of dementia in view of the pers...

Young-onset dementia following chronic abuse of amphetamine-type stimulants

“…12 The sole published case report on amphetaminerelated dementia from Australia involved a 48-year-old Australian man who had been using amphetamines for approximately 30 years. 7 This patient struggled with maintaining task continuity and frequently experienced lapses in remembering appointments, names, and familiar faces. More pronounced impairments were observed in the memory and verbal fluency domains than in the attention and orientation domains.…”

“…More pronounced impairments were observed in the memory and verbal fluency domains than in the attention and orientation domains. 7 …”

“… 6 However, to date, only one case of amphetamine-related dementia has been reported. 7 Herein, we present the case of a middle-aged man with YOD following a prolonged history of ATS abuse and provide a comprehensive literature review.…”