Mild cognitive impairment and dementia in a heterogeneous elderly population: prevalence and risk profile

Abstract

Objective: To describe the demographic, clinical and risk profile of Mild Cognitive Impairment and dementia in a sample of elderly South Africans within a residential setting. Method: One hundred and forty participants residing in a group of residential homes for the elderly were assessed by psychiatrists and assigned diagnoses of dementia or Mild Cognitive Impairment (MCI). Participants diagnosed with dementia were also offered haematological investigations and a CT scan of the brain. Results: The sample consisted of 140 participants comprising 46.4% White, 29.3% Coloured, 20% Asian and 4.3% Black participants. There were 97 (69.3%) females and 106 (75.7%) participants had less than 12 years of education. Eleven (7.9%) dementia and 38 (27.1%) MCI cases were diagnosed. Increasing age was associated with cognitive impairment (MCI and dementia) (p=.020) but there was no association between gender and cognitive impairment (p=.165). MCI was significantly associated with a lower education level (p=.036) and no association was found between depression (current-p=.646; past-p=.719) and dementia or MCI. The presence of vascular risk factors (n=140) ranged from 66.4% (hypertension) to 14.3% (stroke). Subjective memory complaints were significantly associated with cognitive impairment (p=.001). Except for the use of the telephone (p=.225) and the television (p=.08), impairment in all domains of instrumental activities of daily living that were assessed were significantly associated with a dementia diagnosis. Conclusion: The study showed that cognitive impairment was associated with increasing age and low education levels. The presence of vascular risk factors places this population at risk for future cognitive decline. ?? differences in the risk profile (low levels of cardiovascular risk and hypolipidaemia) in LAMIC populations may be contributing to the lower rates. 1 While the incidence and prevalence of dementia have been extensively studied in Western and European countries 5 there remains a dearth of similar studies from Africa. The few studies conducted in Africa prior to 2000 used small samples and was reported to have used 'non-standardised clinical assessments'. 10 Recent studies from Africa reported prevalence figures ranging from 2.6% to 8.1%. 11,12,13 Dementia studies from South Africa include a Western Cape sample of coloured people 14 , with a prevalence of 8.6%, and a Free State sample of indigenous Sotho-speaking elderly black people 15 , which reported a prevalence of 7.7%. This paper describes the clinical and risk profile of a sample of elderly participants who were assessed for the presence of dementia and MCI. In addition, the value of functional assessments and subjective memory complaints in case-finding are also explored. Keywords MethodThe study consisted of three stages: 1) Administration of dementia screening tools; 2) Clinical diagnostic evaluation for dementia; and 3) Administration of a neuropsychological battery of tests. SampleThe study population comprised residents (N=1450) of a ...

The Sensitivity and Specificity of Subjective Memory Complaints and the Subjective Memory Rating Scale, Deterioration Cognitive Observee, Mini-Mental State Examination, Six-Item Screener and Clock Drawing Test in Dementia Screening

“…The prevalence data for dementia and MCI are reported fully in a separate paper [41] . Table 1 also reports on the performance of the various assessment measures.…”

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Dysphoria is a risk factor for depression in medically ill older people

“…medically ill patients have more visitors and general company, regular meals and medical attention). It is important to highlight that a similar lack of association between cognitive impairment and depression was reported recently for community dwelling people with MCI (Ramlall et al ., ), suggesting that there may be additional modifiable factors that can influence and prevent the development of negative cognition in older adults.…”

Mild Cognitive Impairment in Rural Tanzania: Prevalence, Profile, and Outcomes at 4-Year Follow-up

“…A recent study from South Africa that assessed 140 elderly care home residents found 38 people (27.1%) had MCI according to the international consensus criteria. 13 MCI was significantly associated with lower education levels.…”