CONCLUSION: In this review, we will discuss the possible mechanisms which may relate the association between MetS and cognitive decline which include vascular damages, elevation of reactive oxygen species (ROS), insulin resistance and low-grade inflammation.
METHOD: Cognitive decline was determined by Montreal Cognitive Assessment (MoCA). Oxidative stress markers (malondialdehyde-MDA and superoxide dismutase-SOD) were determined and DNA damage was assayed using Alkaline Comet Assay. Toenail samples were taken and analyzed using ICP-MS to determine trace element levels.
RESULTS: A total of 62.1 % of subjects had cognitive impairment. Subjects with cognitive impairment had significantly higher levels of MDA and DNA damage as compared to the group with normal cognitive function; MDA (2.07 ± 0.05 nmol/L vs 1.85 ± 0.06 nmol/L) (p<0.05) and DNA damage (% Tail Density, 14.52 ± 0.32 vs 10.31 ± 0.42; Tail Moment, 1.79 ± 0.06 vs 1.28 ± 0.06) (p<0.05 for all parameters). However, the level of SOD among subjects with cognitive impairment (6.67 ± 0.33 u.e/min/mg protein) was lower than the level among those with normal cognitive functions (11.36 ± 0.65 u.e/min/mg protein) (p<0.05). Multiple logistic regression revealed the predictors for cognitive impairment among the subjects were DNA damage (Adjusted odd ratio [OR], 1.37; 95% confidence interval [CI], 1.18-1.59), level of trace elements in toenails namely, lead (OR, 2.471; CI, 1.535-3.980) and copper (OR, 1.275; CI, 1.047-1.552) (p<0.05).
CONCLUSION: High levels of lead and copper can lead to increase in oxidative stress levels and are associated with DNA damage that eventually could be associated with cognitive decline.
DESIGN: Data on sociodemographic background were obtained from parents. Height and weight were measured and BMI-for-age was determined. Adolescents were interviewed on their habitual dietary intakes using a semi-quantitative FFQ. Cognitive ability was assessed using the Wechsler Nonverbal Scale of Ability in a one-to-one manner. Dietary patterns were constructed using principal component analysis based on thirty-eight food groups of the semi-quantitative FFQ.
SETTING: Urban secondary public schools in the district of Gombak in Selangor, Malaysia.
SUBJECTS: Malay adolescents aged 12 to 13 years (n 416).
RESULTS: The mean general cognitive ability score was 101·8 (sd 12·4). Four major dietary patterns were identified and labelled as 'refined-grain pattern', 'snack-food pattern', 'plant-based food pattern' and 'high-energy food pattern'. These dietary patterns explained 39·1 % of the variance in the habitual dietary intakes of the adolescents. The refined-grain pattern was negatively associated with processing speed, which is a construct of general cognitive ability. The high-energy food pattern was negatively associated with general cognitive ability, perceptual reasoning and processing speed. Monthly household income and parents' educational attainment were positively associated with all of the cognitive measures. In multivariate analysis, only the high-energy food pattern was found to contribute significantly towards general cognitive ability after controlling for socio-economic status.
CONCLUSIONS: Consumption of foods in the high-energy food pattern contributed towards general cognitive ability after controlling for socio-economic status. However, the contribution was small.
METHODS: Twenty-nine children in each group, matched for age, sex and ethnicity, were assessed using the Glasgow outcome Scale (GOS), Weschler Intelligence Scale for Children (WISC-III), Movement Assessment Battery for Children (Movement ABC), Wide Range Assessment of Learning and Memory (WRAML) and a standardised neurological examination 6 months post-injury. Parental reporting of pre- and post-injury behaviour was documented using the Child Behaviour Checklist (CBCL).
RESULTS: Seven (24.1%) children with sCHI and three (10.3%) orthopaedic controls had residual motor deficits. Three (10.3%) children with sCHI and none in the other groups faced problems with independent ambulation. Twenty-seven (93.1%) of those with sCHI and all children in the other groups had GOS scores of good recovery or moderate disability. Twenty-two (81.5%) sCHI, five (18.5%) mCHI and one (3.7%) orthopaedic control reported a deterioration in school performance. MANOVAS identified a significant injury group effect for performance skills (P = 0.007), verbal skills (P = 0.002), memory and learning (P = 0.001) and motor skills (P = 0.001). Repeated measures ANOVA for pre- and post-injury CBCL scores showed significant differences related to somatic complaints (P = 0.004), problems of socialising (P = 0.003), delinquency (P = 0.004), aggressiveness (P = 0.010), thought (P < 0.001) and attention (P < 0.001). Post-hoc univariate analysis showed the significant differences were between that of the sCHI children and the other two groups.
CONCLUSION: Although most sCHI children seemed to have made good physical recovery, there were cognitive, motor, memory and learning difficulties and behavioural problems concomitant with a deterioration in school performance compared with those with lesser or no head injury. This highlights the need for better integrated rehabilitation services to enable a gradual return into mainstream school.
METHODS: A total of 2406 Malaysian children aged 5 to 12 years, who had participated in the South East Asian Nutrition Surveys (SEANUTS), were included in this study. Cognitive performance [non-verbal intelligence quotient (IQ)] was measured using Raven's Progressive Matrices, while socioeconomic characteristics were determined using parent-report questionnaires. Body mass index (BMI) was calculated using measured weight and height, while BMI-for-age Z-score (BAZ) and height-for-age Z-score (HAZ) were determined using WHO 2007 growth reference.
RESULTS: Overall, about a third (35.0%) of the children had above average non-verbal IQ (high average: 110-119; superior: ≥120 and above), while only 12.2% were categorized as having low/borderline IQ ( 3SD), children from very low household income families and children whose parents had only up to primary level education had the highest prevalence of low/borderline non-verbal IQ, compared to their non-obese and higher socioeconomic counterparts. Parental lack of education was associated with low/borderline/below average IQ [paternal, OR = 2.38 (95%CI 1.22, 4.62); maternal, OR = 2.64 (95%CI 1.32, 5.30)]. Children from the lowest income group were twice as likely to have low/borderline/below average IQ [OR = 2.01 (95%CI 1.16, 3.49)]. Children with severe obesity were twice as likely to have poor non-verbal IQ than children with normal BMI [OR = 2.28 (95%CI 1.23, 4.24)].
CONCLUSIONS: Children from disadvantaged backgrounds (that is those from very low income families and those whose parents had primary education or lower) and children with severe obesity are more likely to have poor non-verbal IQ. Further studies to investigate the social and environmental factors linked to cognitive performance will provide deeper insights into the measures that can be taken to improve the cognitive performance of Malaysian children.