Principal component analysis to identify the major contributors to task-activated neurovascular responses

Background: Consensus on the optimal metrics for neurovascular coupling (NVC) is lacking. The aim of this study was to use principal component analysis (PCA) to determine the most significant contributors to NVC responses in healthy adults (HC), Alzheimer's disease (AD), and mild cognitive impairment (MCI). New method: PCA was applied to three datasets: 1) 69 HC, 2) 30 older HC, 34 AD, and 22 MCI, 3) 1&2 combined. Data were extracted on peak percentage change in cerebral blood flow velocity (CBFv), variance ratio (VR), cross-correlation function peak (CCF), and blood pressure, for five cognitive tasks. An equamax rotation was applied and factors were significant where the eignevalue was ≥1. Rotated factor loadings ≥0.4 determined significant NVC variables. Results: PCA identified 12 significant factors accounting for 78% of variance (all datasets). Contributing variables loaded differently on the factors across the datasets. In datasets 1&2, peak percentage change in CBFv contributed to factors explaining the most variance (45–58%), whereas cognitive test scores, fluency and memory domains contributed the least (15–37%). In the combined dataset, CBFv, CCF and fluency domain contributed the majority (33–43%), whereas VR and attention the least (6–24%). Conclusions: Peak percentage change in CBFv and the visuospatial task consistently accounted for a large proportion of the variance, suggesting these are robust NVC markers for future studies

What would help young people who feel down? Voices of young people. A Youth19 Brief.

No description supplie

New Zealand Youth19 survey: vaping has wider appeal than smoking in secondary school students, and most use nicotine-containing e-cigarettes

Objective: To investigate smoking and vaping in secondary school students (aged 13–18 years) in New Zealand (NZ) following the introduction of ‘pod’ e-cigarettes, which have been associated with the rapid escalation of youth vaping elsewhere. Methods: Data on smoking and vaping were collected in 2019 as part of a comprehensive youth health survey (N=7,721). Results: Vaping was 2–3 times more prevalent than smoking, with 10% of students vaping regularly (monthly or more often), and 6% weekly or more often, compared with 4% and 2%, respectively, for tobacco smoking. Nicotine-containing e-cigarettes were sometimes or always used by 80% of regular and 90% of weekly vapers. Regular and weekly smoking was rare in low deprivation (affluent) areas, whereas regular and weekly vaping prevalence was similar across the socioeconomic spectrum. More than 80% of ever-vapers (N=2732) reported they were non-smokers when they first vaped, and 49% of regular vapers (N=718) had never smoked. Conclusions: A significant proportion of New Zealand adolescents, many of whom have never smoked, use nicotine-containing e-cigarettes regularly. Implications for public health: Vaping is less harmful than smoking, but it is not harmless. Public health action is needed to support young non-smokers to remain smokefree and vape-free

Rapid and unequal decline in adolescent mental health and well-being 2012–2019: Findings from New Zealand cross-sectional surveys

Objective: To investigate prevalence and trends in key mental health and well-being indicators among New Zealand secondary school students. Methods: Representative cross-sectional youth health surveys with 2–4% of the New Zealand secondary school population were conducted in 2001, 2007, 2012 and 2019 (total n = 34,548). Results: In 2019, 69.1% reported good well-being (95% confidence interval = [67.6, 70.6]; World Health Organization 5-item), 22.8% reported clinically significant depression symptoms (95% confidence interval = [21.4, 24.1]; Reynolds Adolescent Depression Scale–Short Form) and 41.8% reported possible anxiety symptoms (95% confidence interval = [40.5, 43.2]; Generalized Anxiety Disorder 2, adapted). Past-year prevalence of periods of low mood (38.3%, 95% confidence interval = [36.6, 40.1]), deliberate self-harm (24.1%, 95% confidence interval = [22.8, 25.4]), suicide thoughts (20.8%, 95% confidence interval = [19.2, 22.4]) and suicide attempts (6.3%, 95% confidence interval = [5.5, 7.0]) were observed. After relative stability from 2001 to 2012, there were large declines in mental health to 2019. The proportion reporting good well-being decreased (odds ratio 0.71, 95% confidence interval = [0.65, 0.78], p < 0.001), depression symptoms increased (odds ratio 1.96, 95% confidence interval = [1.75, 2.20], p < 0.001) and past-year suicide thoughts and suicide attempts increased (odds ratio 1.41, 95% confidence interval = [1.25, 1.59], p < 0.001; odds ratio 1.60, 95% confidence interval = [1.32, 1.92], p < 0.001). Past-year deliberate self-harm was largely stable. Declines in mental health were unevenly spread and were generally greater among those with higher need in 2012 (females, Māori and Pacific students and those from higher deprivation neighbourhoods), increasing inequity, and among Asian students. Conclusion: Adolescent mental health needs are high in New Zealand and have increased sharply from 2012 among all demographic groups, especially females, Māori, Pacific and Asian students and those from high-deprivation neighbourhoods. Ethnic and socioeconomic disparities have widened

Te āniwaniwa takatāpui whānui: Te aronga taera mō ngā rangatahi | Sexual attraction and young people’s wellbeing in Youth19.

No description supplie

Indigenous adolescent health in Aotearoa New Zealand: Trends, policy and advancing equity for rangatahi Maori, 2001–2019

Background: Rangatahi Māori, the Indigenous adolescents of Aotearoa New Zealand (NZ), have poorer health outcomes than Pākehā (NZ European /other European/“White”) adolescents. We explored the influence of policies for Indigenous youth by presenting health trends, inequities and contrasting policy case examples: tobacco control and healthcare access. Methods: Cross-sectional representative surveys of NZ secondary school students were undertaken in 2001, 2007, 2012 and 2019. Health indicators are presented for Māori and Pākehā adolescents (relative risks with 95% CI, calculated using modified Poisson regression) between 2001–2019 and 2012–2019. Policy examples were examined utilising Critical Te Tiriti Analysis (CTA). Findings: Rangatahi Māori reported significant health gains between 2001 and 2019, but an increase in depressive symptoms (13.8% in 2012 to 27.9% in 2019, RR 2.01 [1.65–2.46]). Compared to Pākehā youth there was a pattern of persistent Māori disadvantage, particularly for racism (RR 2.27 [2.08–2.47]), depressive symptoms (RR 1.42 [1.27–1.59]) and forgone healthcare (RR 1.63 [1.45–1.84]). Tobacco use inequities narrowed (RR 2.53 [2.12–3.02] in 2007 to RR 1.55 [1.25–1.93] in 2019). CTA reveals rangatahi Māori-specific policies, Māori leadership, and political support aligned with improved outcomes and narrowing inequities. Interpretation: Age-appropriate Indigenous strategies are required to improve health outcomes and reduce inequities for rangatahi Māori. Characteristics of effective strategies include: (1) evidence-based, sustained, and comprehensive approaches including both universal levers and Indigenous youth-specific policies; (2) Indigenous and rangatahi leadership; (3) the political will to address Indigenous youth rights, preferences, priorities; and (4) a commitment to an anti-racist praxis and healthcare Indigenisation. Funding: Two Health Research Council of New Zealand Project Grants: (a) Fleming T, Peiris–John R, Crengle S, Parry D. (2018). Integrating survey and intervention research for youth health gains. (HRC ref: 18/473); and (b) Clark TC, Le Grice J, Groot S, Shepherd M, Lewycka S. (2017) Harnessing the spark of life: Maximising whānau contributors to rangatahi wellbeing (HRC ref: 17/315)

The impact of viral mutations on recognition by SARS-CoV-2 specific T cells

We identify amino acid variants within dominant SARS-CoV-2 T cell epitopes by interrogating global sequence data. Several variants within nucleocapsid and ORF3a epitopes have arisen independently in multiple lineages and result in loss of recognition by epitope-specific T cells assessed by IFN-γ and cytotoxic killing assays. Complete loss of T cell responsiveness was seen due to Q213K in the A∗01:01-restricted CD8+ ORF3a epitope FTSDYYQLY207-215; due to P13L, P13S, and P13T in the B∗27:05-restricted CD8+ nucleocapsid epitope QRNAPRITF9-17; and due to T362I and P365S in the A∗03:01/A∗11:01-restricted CD8+ nucleocapsid epitope KTFPPTEPK361-369. CD8+ T cell lines unable to recognize variant epitopes have diverse T cell receptor repertoires. These data demonstrate the potential for T cell evasion and highlight the need for ongoing surveillance for variants capable of escaping T cell as well as humoral immunity