Muscular strength across the life course: The tracking and trajectory patterns of muscular strength between childhood and mid-adulthood in an Australian cohort

ObjectivesLow muscular strength is a risk factor for current and future adverse health outcomes. However, whether levels of muscular strength persist, or track, and if there are distinct muscular strength trajectories across the life course is unclear. This study aimed to explore muscular strength trajectories between childhood and mid-adulthood.DesignProspective longitudinal study.MethodsChildhood Determinants of Adult Health Study participants had their muscular strength (right and left handgrip, shoulder extension and flexion, and leg strength measured by hand-held, shoulder and leg-back dynamometers, and a combined strength score) assessed in childhood, young adulthood and mid-adulthood. The tracking of muscular strength was quantified between childhood and mid-adulthood (n = 385) and young- and mid-adulthood (n = 822). Muscular strength trajectory patterns were identified for participants who had their muscular strength assessed at least twice across the life course (n = 1280).ResultsLevels of muscular strength were persistent between childhood and mid-adulthood and between young- and mid-adulthood, with the highest tracking correlations observed for the combined strength score (childhood to mid-adulthood: r = 0.47, p ConclusionsWeak children are likely to become weak adults in midlife unless strategies aimed at increasing muscular strength levels are introduced. Whether interventions aimed at increasing muscular strength could be implemented in childhood to help establish favourable muscular strength trajectories across the life course and in turn, better future health, warrant further attention.</p

The Association Between Grip Strength Measured in Childhood, Young- and Mid-adulthood and Prediabetes or Type 2 Diabetes in Mid-adulthood

Background Although low child and adult grip strength is associated with adverse cardiometabolic health, how grip strength across the life course associates with type 2 diabetes is unknown. This study identified the relative contribution of grip strength measured at specific life stages (childhood, young adulthood, mid-adulthood) with prediabetes or type 2 diabetes in mid-adulthood.Methods Between 1985 and 2019, 263 participants had their grip strength measured using an isometric dynamometer in childhood (9-15 years), young adulthood (28-36 years) and mid-adulthood (38-49 years). In mid-adulthood, a fasting blood sample was collected and tested for glucose and glycated haemoglobin (HbA1c). Participants were categorized as having prediabetes or type 2 diabetes if fasting glucose levels were >= 5.6 mmol or if HbA1c levels were >= 5.7% (>= 39 mmol/mol). A Bayesian relevant life course exposure model examined the association between lifelong grip strength and prediabetes or type 2 diabetes.Results Grip strength at each time point was equally associated with prediabetes or type 2 diabetes in mid-adulthood (childhood: 37%, young adulthood: 36%, mid-adulthood: 28%). A one standard deviation increase in cumulative grip strength was associated with 34% reduced odds of prediabetes or type 2 diabetes in mid-adulthood (OR 0.66, 95% credible interval 0.40, 0.98).Conclusions Greater grip strength across the life course could protect against the development of prediabetes and type 2 diabetes. Strategies aimed at increasing muscular strength in childhood and maintaining behaviours to improve strength into adulthood could improve future cardiometabolic health.</div

Lower grip strength in youth with obesity identifies those with increased cardiometabolic risk

Background: We examined whether grip strength differentiates youth with obesity with increased cardiometabolic risk.Methods: The sample comprised 43 youth with severe obesity (mean age 14.8, standard deviation 3.0 years) enrolled in the Childhood Overweight BioRepository of Australia. Grip strength was normalized to body mass and categorized as low and moderate/high.Results: Youth with low grip strength had higher systolic blood pressure (mean difference 13 mmHg), lowdensity lipoprotein cholesterol (0.26 mmol/l), continuous metabolic syndrome score (0.36), and carotid intima-media thickness (0.05 mm) compared with those with moderate/high grip strength.Conclusions: Low grip strength may differentiate youth with obesity with increased cardiometabolic risk.</p

The great leap backward: changes in the jumping performance of Australian children aged 11−12-years between 1985 and 2015

Previous data have indicated relative stability over time of paediatric jumping performance, but few data exist since the early 2000s. This study quantified the 30-year secular changes in jumping performance of Australian children aged 11−12-years using data from the Australian Schools Health and Fitness Survey (1985, n = 1967) and Growing Up in Australia’s Child Health CheckPoint (2015, n = 1765). Both cohorts measured jumping performance (standing long jump distance), anthropometric and demographic data. Secular changes in jumping performance means and quantiles were examined using multivariable linear and quantile regression. Between 1985 and 2015, jumping performance declined by 16.4 cm or by 11.2% (standardised change 0.66 SD, 95%CI 0.60 to 0.73). Adjustment for body mass reduced the effect by 32%, although the decline remained (absolute change – 11.1 cm, 95%CI −12.5 to −9.7; percent change 7.7%, 95%CI 6.7 to 8.6; standardised change 0.51 SD, 95%CI 0.44 to 0.57). This decline was evident across all quantiles. The jumping performance of Australian children aged 11−12-years has declined between 1985 and 2015, with body mass changes accounting for only part of the decline. Efforts should continue to promote paediatric muscular fitness, reduce adiposity, and aim to reverse this decline in jumping performance.</p

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI &lt;18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For school&#x2;aged children and adolescents, we report thinness (BMI &lt;2 SD below the median of the WHO growth reference) and obesity (BMI &gt;2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

Genomic reconstruction of the SARS-CoV-2 epidemic in England.

The evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus leads to new variants that warrant timely epidemiological characterization. Here we use the dense genomic surveillance data generated by the COVID-19 Genomics UK Consortium to reconstruct the dynamics of 71 different lineages in each of 315 English local authorities between September 2020 and June 2021. This analysis reveals a series of subepidemics that peaked in early autumn 2020, followed by a jump in transmissibility of the B.1.1.7/Alpha lineage. The Alpha variant grew when other lineages declined during the second national lockdown and regionally tiered restrictions between November and December 2020. A third more stringent national lockdown suppressed the Alpha variant and eliminated nearly all other lineages in early 2021. Yet a series of variants (most of which contained the spike E484K mutation) defied these trends and persisted at moderately increasing proportions. However, by accounting for sustained introductions, we found that the transmissibility of these variants is unlikely to have exceeded the transmissibility of the Alpha variant. Finally, B.1.617.2/Delta was repeatedly introduced in England and grew rapidly in early summer 2021, constituting approximately 98% of sampled SARS-CoV-2 genomes on 26 June 2021

Association Between Risk Factors in Childhood and Sex Differences in Prevalence of Carotid Artery Plaques and Intima‐Media Thickness in Mid‐Adulthood in the Childhood Determinants of Adult Health Study

Background The origins of sex differences in cardiovascular diseases are not well understood. We examined the contribution of childhood risk factors to sex differences in adult carotid artery plaques and intima‐media thickness (carotid IMT). Methods and Results Children in the 1985 Australian Schools Health and Fitness Survey were followed up when they were aged 36 to 49 years (2014–19, n=1085–1281). Log binomial and linear regression examined sex differences in adult carotid plaques (n=1089) or carotid IMT (n=1283). Childhood sociodemographic, psychosocial, and biomedical risk factors that might contribute to sex differences in carotid IMT/plaques were examined using purposeful model building with additional adjustment for equivalent adult risk factors in sensitivity analyses. Women less often had carotid plaques (10%) than men (17%). The sex difference in the prevalence of plaques (relative risk [RR] unadjusted 0.59 [95% CI, 0.43 to 0.80]) was reduced by adjustment for childhood school achievement and systolic blood pressure (RR adjusted 0.65 [95% CI, 0.47 to 0.90]). Additional adjustment for adult education and systolic blood pressure further reduced sex difference (RR adjusted 0.72 [95% CI, 0.49 to 1.06]). Women (mean±SD 0.61±0.07) had thinner carotid IMT than men (mean±SD 0.66±0.09). The sex difference in carotid IMT (β unadjusted −0.051 [95% CI, −0.061 to −0.042]) reduced with adjustment for childhood waist circumference and systolic blood pressure (β adjusted −0.047 [95% CI, −0.057 to −0.037]) and further reduced with adjustment for adult waist circumference and systolic blood pressure (β adjusted −0.034 [95% CI, −0.048 to −0.019]). Conclusions Some childhood factors contributed to adult sex differences in plaques and carotid IMT. Prevention strategies across the life course are important to reduce adult sex differences in cardiovascular diseases