Researchers in Community & Health Sciences

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Browsing by Author "Bhigjee, Ahmed"

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    Mild cognitive impairment and dementia in a heterogeneous elderly population: prevalence and risk profile
    (OMICS Publishing Group, 2013) Ramlall, Suvira; Chipps, Jennifer; Pillay, Basil; Bhigjee, Ahmed
    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.
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    Screening a heterogeneous elderly South African population for cognitive impairment: the utility and performance of the Mini-Mental State Examination, Six Item Screener, Subjective Memory Rating Scale and Deterioration Cognitive Observee
    (OMICS Publishing Group, 2013) Ramlall, Suvira; Chipps, Jennifer; Pillay, Basil; Bhigjee, Ahmed
    OBJECTIVE: The aim of this study was to report on the prevalence of cognitive impairment, and to assess the performance and utility of subjective, objective and informant screening tools in a heterogeneous community sample. METHOD: A sample of 302 elderly participants (>60 years) living in residential homes in a large city in South Africa were screened for the presence of cognitive impairment using objective (Mini-Mental State Examination [MMSE] and Six Item Screener-[SIS]), subjective (Subjective Memory Complaint [SMC]and Subjective Memory Rating Scale [SMRS]) and informant (Deterioration Cognitive Observee [DECO]) screening tools. All tools were compared to the MMSE and the influence of demographic variables on the performance on these tools was considered. RESULTS: Significantly lower MMSE scores were found in participants aged 80-89 years (p=.023) and those who had 8-11 years of education (p=.002). For every one additional year of education, participants were 0.71 times less likely to screen positive on the MMSE. Differential item functioning on various components of the MMSE was demonstrated due to the effects of education, race and gender. There was significant differential performance between the recommended and alternate attention/concentration items (p<.001) with the alternate item favouring better performance. Based on the MMSE cutoff score of < 23, the prevalence of cognitive impairment was 16.9%; the prevalence yielded by the remaining tools ranged from 10.5% using the DECO to 46% as determined by the presence of a SMC. Using the MMSE as the reference standard for the presence of cognitive impairment, the SIS, SMC, SMRS and DECO had sensitivities of 82.3%, 54.6%, 17.0% and 37.5%, and specificities of 71.3%, 57.6%, 87.4% and 96.7% respectively. Age and race influenced performance on the MMSE, SIS and SMRS. CONCLUSION: Different types of cognitive screening tools yielded varying sensitivities and specificities for identifying cognitive impairment when compared to the MMSE. The influence of race, age and education on test performance highlights the need for suitable, culture-fair screening tools. Locally, the alternate item for attention/concentration should be preferred.
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    Sensitivity and specificity of neuropsychological tests for dementia and mild cognitive impairment in a sample of residential elderly in South Africa
    (Health & Medical Publishing Group, 2014) Chipps, Jennifer; Ramlall, Suvira; Pillay, Basil; Bhigjee, Ahmed
    BACKGROUND. Neuropsychological tests can successfully distinguish between healthy elderly persons and those with clinically significant cognitive impairment. Objectives. A battery of neuropsychological tests was evaluated for their discrimination validity of cognitive impairment in a group of elderly persons in Durban, South Africa. METHOD. A sample of 117 English-speaking participants of different race groups (9 with dementia, 30 with mild cognitive impairment (MCI) and 78 controls) from a group of residential homes for the elderly was administered a battery of 11 neuropsychological tests. Kruskal-Wallis independent sample tests were used to compare performance of tests in the groups. Sensitivity and specificity of the tests for dementia and MCI were determined using random operating curve (ROC) analysis. RESULTS. Most tests were able to discriminate between participants with dementia or MCI, and controls (p<0.05). Area under the curve (AUC) values for dementia v. non-dementia participants ranged from 0.519 for the digit span (forward) to 0.828 for the digit symbol (90 s), with 14 of the 29 test scores achieving significance (p<0.05). AUC values for MCI participants ranged from 0.754 for controlled oral word association test (COWAT) (Animal) to 0.507 for the Rey complex figure test copy, with 17 of the 29 scores achieving significance (p<0.05). CONCLUSION. Several measures from the neuropsychological battery had discrimination validity for the differential diagnosis of cognitive disturbances in the elderly. Further studies are needed to assess the effect of culture and language on the appropriateness of the tests for different populations.
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    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.
    (Karger, 2013) Ramlall, Suvira; Chipps, Jennifer; Bhigjee, Ahmed; Pillay, Basil
    Background: The effectiveness of dementia screening depends on the availability of suitable screening tools with good sensitivity and specificity to confidently distinguish normal age-related cognitive decline from dementia. The aim of this study was to evaluate the discriminant validity of 7 screening measures for dementia. Methods: A sample of 140 participants aged ≥60 years living in a residential facility for the aged were assessed clinically and assigned caseness for dementia using the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revised diagnostic criteria. Sensitivity and specificity of a selection of the following screening measures were tested using receiver operating characteristic (ROC) analysis for individual and combined tests: the Mini-Mental State Examination (MMSE), Six-Item Screener (SIS), Subjective Memory Complaint, Subjective Memory Complaint Clinical (SMCC), Subjective Memory Rating Scale (SMRS), Deterioration Cognitive Observee (DECO) and the Clock Drawing Test (CDT). Results: Using ROC analyses, the SMCC, MMSE and CDT were found to be ‘moderately accurate' in screening for dementia with an area under the curve (AUC) >0.70. The AUCs for the SIS (0.526), SMRS (0.661) and DECO (0.687) classified these measures as being ‘less accurate'. At recommended cutoff scores, the SMCC had a sensitivity of 90.9% and specificity of 45.7%; the MMSE had a sensitivity of 63.6% and a specificity of 76.0%, and the CDT had a sensitivity of 44.4% and a specificity of 88.9%. Combining the SMCC and MMSE did not improve their predictive power except for a modest increase when using the sequential rule. Conclusion: The SMCC is composed of valid screening questions that have high sensitivity, are simple to administer and ideal for administration at the community or primary health care level as a first level of ‘rule-out' screening. The MMSE can be included at a second stage of screening at the general hospital level and the CDT in specialist clinical settings. Sequential use of the SMCC and MMSE will improve the specificity of the former and the sensitivity of the latter.