The IQCODE: an alternative screening test for dementia for low educated Thai elderly.

OBJECTIVE: To explore an alternative method of screening for dementia in Thai elderly people who have a low educational level. The Informant Questionnaire on Cognitive Decline in the elderly (IQCODE) is used as the screening test. MATERIAL AND METHOD: A community based population of elderly subjects in Bangkok including 87 normal subjects and 73 demented elderly people were studied. Their ages ranged from 52 to 85 years old. The majority of the elderly people had had four years or less of primary-education. Dementia was diagnosed independently by DSM IV criteria. A short form of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE), a short form, was administered to informants of the elderly by trained medical personnel. The Thai Mini Mental State Examination (TMSE) was also administered to these subjects and compared with the IQCODE. SPSS 9.0 was used for statistical analysis. RESULTS: The IQCODE showed a negative correlation with the TMSE (n=160, r=-0.679, p<0.001). The area under the receiver operating characteristic curve (ROC) of the IQCODE was larger than that of TMSE (0.928 vs 0.814). On logistic regression analysis, there were only three questions that contributed to the diagnosis that showed statistical significance. These questions are remembering what day and month it is, learning how to use a new gadget and handling other everyday arithmetic problems. Applying the new formula (z-score), these three questions showed a sensitivity of 84.90 per cent, and a specificity of 92 per cent for the diagnosis of dementia. CONCLUSION: Informants' perceptions of cognitive impairment of the elderly can be reliably applied as a screening instrument for dementia in the Thai population with a variety of educational levels. A short form of the IQCODE using selected questions can be administered with good diagnostic sensitivity and specificity.

Risk factors for dementia and impaired cognitive status in Thai elderly.

OBJECTIVE: To examine the association of physical and biochemical risk factors for dementia and cognitive status in an urban population based Thai elderly. MATERIAL AND METHOD: This study was part of an integrated health research project from 1997 to 1999. Subjects were 550 elders who lived in a community within 10 km from Siriraj Hospital, Bangkok, Thailand. They were 55 years and older. Thai mental state examination (TMSE) was applied to all subjects as the screening test for dementia. Those who scored less than or equal to 24 out of 30 were categorised as having cognitive impairment or suspected of having dementia, and they were then examined in detail for the diagnosis of dementia using the DSM IV criteria. Blood pressure and body weight were recorded. Blood was drawn for biochemical and haematological analysis including the serology for syphilis and thyroid function test as the basic screening investigation for dementia. Descriptive data, expressed as the mean, standard deviation, Pearson Chi square and ANOVA tests were analysed with SPSS 9.0 in the study. RESULTS: Of 550 subjects, 261 (47.45%) were classified as the normal subjects group, 49 (8.91%) as the cognitively impaired group, and 240 (43.82%) as the dementia group. 377 subjects (68.55%) were female and the distribution of females in each subgroup ranged from 63.3-75.5 per cent. The mean age in the normal group was 67.47 +/- 6.05 years, the cognitively impaired group was 70.14 years and the dementia group was 69.63 +/- 9.21 years. Systolic blood pressure (BP), diastolic BP, serum cholesterol, SGOT, GGT, serum albumin, haemoglobin, MCHC, neutrophil counts and weight were statistically significant factors that were associated with cognitive status. Both systolic and diastolic BP were high in the higher cognitive status group. Serum albumin, serum cholesterol levels and body weight were also higher in the high cognitive status group. CONCLUSION: This study demonstrated an association between nutritional status and cognitive status in Thai elderly. Poorer nutritional factor in lower cognitive function individuals might explain a lower of both systolic and diastolic BP in the dementia subjects compared to the healthy subjects.