The Association Between Persistence and Change in Behavioral Difficulties During Early to Middle Childhood and Cognitive Abilities at Age 8.

We investigated the association between persistence and change in behavioral difficulties during early to middle childhood and several cognitive outcomes. We observed 3904 8-year-olds enrolled in the longitudinal study Growing Up in New Zealand (50% male/female; 23% Maori, 9% Pacific Peoples, 13% Asian, 2% Middle Eastern/Latin American/African, 9% Other, 43% European). The NIH Toolbox Cognition Battery was used to assess cognitive functioning at 8 years and the Strengths and Difficulties Questionnaire for behavioral difficulties at 4.5 and 8 years. Multivariate logistic regression analyses were conducted, controlling for well-known sociodemographic confounders. Children with persistent or later onset of behavioral difficulties were at higher risk for poorer vocabulary, reading, inhibitory control/attention, episodic memory, working memory and processing speed at age 8 compared to children with no or improved difficulties. Our study supports the importance of addressing both cognitive and behavioral aspects when planning educational programmes and interventions in early and middle childhood.

Exploring the Factor Structure of the NIH Toolbox Cognition Battery in a Large Sample of 8-Year-Old Children in Aotearoa New Zealand.

OBJECTIVE: The objective of this study was to derive a factor structure of the measures of the National Institutes of Health (NIH) Toolbox Cognition Battery (CB) that is representative of cognitive abilities in a large ethnically diverse cohort of 8-year-old children in Aotearoa New Zealand. METHODS: Our sample comprised of 4298 8-year-old children from the Growing Up in New Zealand study. We conducted exploratory and confirmatory factor analysis for the NIH Toolbox CB measures to discover the best-fitting factor structure in our sample. Measurement invariance of the identified model was tested across child's gender, socio-economic status (SES), and ethnicity. RESULTS: A three-dimensional factor structure was identified, with one factor of Crystallised Cognition (Reading and Vocabulary), and two distinguished factors of fluid cognition: Fluid Cognition I (Attention/Inhibitory Control, Processing Speed, and Cognitive Flexibility) and Fluid Cognition II (Working Memory, Episodic Memory). The results demonstrate excellent model fit, but reliability of the factors was low. Measurement invariance was confirmed for child's gender. We found configural, but neither metric nor scalar, invariance across SES and the four major ethnic groups: European, Maori, Pacific Peoples, and Asian. CONCLUSION: Our findings show that, at the age of 8 years, fluid abilities are more strongly associated with one another than with crystallised abilities and that fluid abilities need to be further differentiated. This dimensional structure allows for comparisons across child's gender, but evaluations across SES and ethnicity within the Aotearoa New Zealand context must be conducted with caution. We recommend using raw scores of the individual NIH Toolbox CB measures in future research.

Peritoneal dialysis is associated with better cognitive function than hemodialysis over a one-year course.

Impaired cognitive functioning in patients with end-stage renal disease may reduce their capabilities to adhere to complex medical or dietary regimens and to fully participate in medical decisions. With decreasing renal function, cognitive abilities are likely to decline, with cognitive dysfunction improving after initiation of dialysis and even being generally reversible after successful renal transplantation. However, little is known about cognitive changes particularly regarding different treatment modalities. To gain further insight into this, we focused on a one-year course of cognitive functions, comparing peritoneal to hemodialysis patients. Within the CORETH-project, two validated neurocognitive tests, assessing executive functioning (Trail Making Test-B) and attention (d2-Revision-Test) and the self-reported Kidney Disease Quality of Life Short Form Cognitive Function-subscale, were administered to 271 patients at baseline and after one year. Subsamples were matched by propensity score, adjusting for age, comorbidity, education, and employment status for 96 hemodialysis and 101 peritoneal dialysis patients. The effects of time and treatment modality were investigated, controlling for well-known confounders. Both tests revealed improvement over one year. Peritoneal dialysis was associated with better outcomes than hemodialysis at baseline and follow-up, but comparability between groups may be limited. The opposite pattern applied to self-reporting. Hemodialysis patients had to be excluded from cognitive testing more often than peritoneal dialysis patients. As such, the number of exclusions may have biased the findings, limiting generalizability. Thus, our findings suggest an improvement of cognitive functioning and support previous indications for peritoneal dialysis being associated with better cognitive functions during a one-year course than hemodialysis.

Social relationships and their impact on health-related outcomes in peritoneal versus haemodialysis patients: a prospective cohort study.

Background: Social relationships are important determinants of health-related outcomes for patients with chronic conditions. However, the effects of social networks and social support on health outcomes of dialysis patients in different treatment modalities have been under studied. Methods: We surveyed peritoneal dialysis (PD) and haemodialysis (HD) patients in the Choice of Renal Replacement Therapy project about their social relationships and health-care outcomes at baseline and 1-year follow-up. Two propensity score-matched groups (n = 353; HD = 200, PD = 153) with similar age, comorbidity level, education and employment status were compared. We used an ego-centred Network Generator to assess quantitative and qualitative aspects of social networks and the Berlin Social Support Scales to evaluate dimensions of social support, and analysed the effects of the social variables on anxiety, depression, autonomy preferences, and physical and psychological quality of life. Results: Over time, the non-family networks (e.g. friends) of both groups decreased (P = 0.04) and the absolute number of types of relationships increased (P = 0.01). The family-network size, quality of relationships and social support remained stable. Larger social networks were associated with higher participation-seeking preferences (B = 1.39, P = 0.002) and lower anxiety (B = -0.11, P = 0.03). Closer and more satisfying relationships were associated with better psychological well-being (B = 3.41, P = 0.003). PD patients had larger networks, more types of relationships and received more social support than HD patients (P ≤ 0.05). Conclusions: These differences may reflect the degree of autonomy and self-care associated with the different treatment modalities. In practice, our findings suggest that the early identification and inclusion of persons providing social support for patients may have a positive effect on different aspects of their care and quality of life.

Ethnic-specific characteristics associated with longitudinal response patterns from prebirth to 12 years: evidence from Growing Up in New Zealand.

BACKGROUND: Longitudinal studies can generate valuable scientific knowledge, but can be compromised by systematic attrition. Previous research shows that sociodemographic characteristics (eg, ethnicity, age, educational level, socioeconomic circumstances) are associated with attrition rates. However, little is known about whether these characteristics differ by ethnicity, and how this impacts cohort retention strategies. METHODS: Using antenatal to 12-year data from the Growing Up in New Zealand birth cohort study (N=6743), we examined transversal response rates by ethnicity (Maori, Pacific, Asian, European), used sequence analysis and cluster analysis to identify unique longitudinal response patterns, and binary logistic regression to examine ethnic-specific sociodemographic characteristics associated with these response patterns. RESULTS: The overall response rate at 12 years was 71.0%, with ethnic differences in response rates widening over the six data collection waves. Three longitudinal response patterns were identified: frequent responders (65.2%), intermittent non-responders (29.6%) and frequent non-responders (5.2%). Sociodemographic characteristics such as younger maternal age and lower maternal education were associated with a higher likelihood of membership in the non-response clusters across all ethnic groups. However, there were also important nuances by ethnicity. Individual level factors (eg, household material deprivation and maternal general health) tended to be associated with non-response for Europeans, whereas structural level factors (eg, area-level deprivation and racial discrimination) tended to be associated with non-response for Maori, Pacific and Asian peoples. CONCLUSION: Ethnic differences in longitudinal response patterns are due to multiple factors of disadvantage, and therefore require targeted retention strategies. Stratifying analyses by ethnicity is important for revealing nuanced insights.

Age at first exposure to antibiotics and neurodevelopmental outcomes in childhood.

RATIONALE: Viral illnesses in children are common and are frequently treated with antibiotic medication. Antibiotics reduce the diversity and composition of the gut microbiota, leading to poor developmental outcomes. OBJECTIVES: To investigate the relationship between age at first exposure to antibiotics and cognitive and behavioural development at 4.5 years while controlling for multiple confounders, including otitis media. METHODS: Study participants were 5589 children enrolled in the broadly generalisable Growing Up in New Zealand cohort study, with antibiotic exposure data, maternal antenatal information, and age 4.5-year behaviour and cognitive outcome data. Children were categorised as first exposed to antibiotics according to the following mutually exclusive ages: 0-2 months; 3-5 months; 6-8 months; 9-11 months; 12-54 months or not exposed by 54 months. Developmental outcome measures included the Strengths and Difficulties Questionnaire, Luria hand clap task, and the Peabody Picture Vocabulary Test-III. RESULTS: In univariate analysis, there was an evident dose-response relationship where earlier exposure to antibiotics in the first year of life was associated with behavioural difficulties, lower executive function scores, and lower receptive language ability. After adjusting for confounders, pairwise comparisons showed that first antibiotic exposure between birth and 3 months or between 6 and 9 months was associated with lower receptive vocabulary. Antibiotic exposure at any age prior to 12 months was associated with increases in behavioural difficulties scores at 4.5 years. CONCLUSIONS: Following adjustment for socioeconomic factors and otitis media, there is evidence that antibiotic exposure during potentially sensitive windows of development is associated with receptive language and behaviour later in childhood.

A longitudinal study of antenatal and perinatal risk factors in early childhood cognition: Evidence from Growing Up in New Zealand.

BACKGROUND: Poor maternal health, disadvantageous exposures during pregnancy and unfavourable perinatal events are associated with adverse trajectories in offspring cognitive development. AIM: To examine longitudinal associations between antenatal maternal, perinatal and maternal health characteristics and children's early cognitive development across executive control, motor ability and receptive language domains. STUDY DESIGN, SUBJECTS AND OUTCOME MEASURES: Analyses comprised interview and observational data from 4587 children and their mothers enrolled in the longitudinal Growing Up in New Zealand cohort study. Children's executive control (Luria hand clap task), motor skills (mothers' report) and receptive language ability (Peabody Picture Vocabulary Test) were assessed at age 4.5 years. Multivariate logistic regression analyses were conducted, controlling for sociodemographic factors. RESULTS: Smoking pre- and during pregnancy, no folate intake during first trimester and low birth weight were risk factors for poorer executive control. Perceived stress during pregnancy, no folate intake during first trimester and low birth weight were all risk factors for poorer motor ability. Smoking pre-pregnancy, antenatal anxiety and no folate intake during first trimester were risk factors for poorer receptive language ability. CONCLUSION: Adverse ante- and perinatal environments are associated with poorer executive control, motor and receptive language abilities in early childhood. Improving maternal education and support especially for more disadvantaged mothers during pregnancy may reduce the potential deleterious impact of adverse ante- and perinatal conditions on children's early cognition.

Cognitive Testing in Patients with CKD: The Problem of Missing Cases.

BACKGROUND AND OBJECTIVES: Cognitive testing is only valid in individuals with sufficient visual and motor skills and motivation to participate. Patients on dialysis usually suffer from limitations, such as impaired vision, motor difficulties, and depression. Hence, it is doubtful that the true value of cognitive functioning can be measured without bias. Consequently, many patients are excluded from cognitive testing. We focused on reasons for exclusion and analyzed characteristics of nontestable patients. DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS: Within the Choice of Renal Replacement Therapy Project (baseline survey: May 2014 to May 2015), n=767 patients on peritoneal dialysis (n=240) or hemodialysis (n=527) were tested with the Trail Making Test-B and the German d2-Revision Test and completed the Kidney Disease Quality of Life Short Form cognition subscale. We divided the sample into patients with missing cognitive testing data and patients with full cognitive testing data, analyzed reasons for nonfeasibility, and compared subsamples with regard to psychosocial and physical metrics. The exclusion categories were linked to patient characteristics potentially associated with missing data (age, comorbidity, depression, and education level) by calculation of λ-coefficient. RESULTS: The subsamples consisted of n=366 (48%) patients with missing data (peritoneal dialysis =62, hemodialysis =304) and n=401 patients with full cognitive testing data (peritoneal dialysis =178, hemodialysis =223). Patients were excluded due to visual impairment (49%), lack of motivation (31%), and motor impairment (13%). The remaining 8% did not follow instructions, suffered from medical incidents, or had language difficulties. Compared with patients with full cognitive testing data, they were more likely to have depression; be treated with hemodialysis; be older, nonworking, or more comorbid; and experience poorer shared decision making. Reasons for exclusion were not related to levels of age, comorbidity score, depression score, or education level. CONCLUSIONS: We excluded almost one half of eligible patients from cognitive testing due to visual, motivational, or motor difficulties. Our findings are consistent with exclusion categories reported from the literature. We should be aware that, because of disease-related limitations, conclusions about cognitive functioning in the CKD population may be biased. In the future, nonvisual and nonverbal cognitive testing can be a valuable resource.