General and abdominal adiposity and hypertension in eight world regions: a pooled analysis of 837 population-based studies with 7•5 million participants

Background Adiposity can be measured using BMI (which is based on weight and height) as well as indices of abdominal adiposity. We examined the association between BMI and waist-to-height ratio (WHtR) within and across populations of different world regions and quantified how well these two metrics discriminate between people with and without hypertension. Methods We used data from studies carried out from 1990 to 2023 on BMI, WHtR and hypertension in people aged 20–64 years in representative samples of the general population in eight world regions. We graphically compared the regional distributions of BMI and WHtR, and calculated Pearson's correlation coefficients between BMI and WHtR within each region. We used mixed-effects linear regression to estimate the extent to which WHtR varies across regions at the same BMI. We graphically examined the prevalence of hypertension and the distribution of people who have hypertension both in relation to BMI and WHtR, and we assessed how closely BMI and WHtR discriminate between participants with and without hypertension using C-statistic and net reclassification improvement (NRI). Findings The correlation between BMI and WHtR ranged from 0·76 to 0·89 within different regions. After adjusting for age and BMI, mean WHtR was highest in south Asia for both sexes, followed by Latin America and the Caribbean and the region of central Asia, Middle East and north Africa. Mean WHtR was lowest in central and eastern Europe for both sexes, in the high-income western region for women, and in Oceania for men. Conversely, to achieve an equivalent WHtR, the BMI of the population of south Asia would need to be, on average, 2·79 kg/m2 (95% CI 2·31–3·28) lower for women and 1·28 kg/m2 (1·02–1·54) lower for men than in the high-income western region. In every region, hypertension prevalence increased with both BMI and WHtR. Models with either of these two adiposity metrics had virtually identical C-statistics and NRIs for every region and sex, with C-statistics ranging from 0·72 to 0·81 and NRIs ranging from 0·34 to 0·57 in different region and sex combinations. When both BMI and WHtR were used, performance improved only slightly compared with using either adiposity measure alone. Interpretation BMI can distinguish young and middle-aged adults with higher versus lower amounts of abdominal adiposity with moderate-to-high accuracy, and both BMI and WHtR distinguish people with or without hypertension. However, at the same BMI level, people in south Asia, Latin America and the Caribbean, and the region of central Asia, Middle East and north Africa, have higher WHtR than in the other regions. Funding UK Medical Research Council and UK Research and Innovation (Innovate UK)

General and abdominal adiposity and hypertension in eight world regions: a pooled analysis of 837 population-based studies with 7·5 million participants

Background Adiposity can be measured using BMI (which is based on weight and height) as well as indices of abdominal adiposity. We examined the association between BMI and waist-to-height ratio (WHtR) within and across populations of different world regions and quantified how well these two metrics discriminate between people with and without hypertension. Methods We used data from studies carried out from 1990 to 2023 on BMI, WHtR and hypertension in people aged 20–64 years in representative samples of the general population in eight world regions. We graphically compared the regional distributions of BMI and WHtR, and calculated Pearson’s correlation coefficients between BMI and WHtR within each region. We used mixed-effects linear regression to estimate the extent to which WHtR varies across regions at the same BMI. We graphically examined the prevalence of hypertension and the distribution of people who have hypertension both in relation to BMI and WHtR, and we assessed how closely BMI and WHtR discriminate between participants with and without hypertension using C-statistic and net reclassification improvement (NRI). Findings The correlation between BMI and WHtR ranged from 0·76 to 0·89 within different regions. After adjusting for age and BMI, mean WHtR was highest in south Asia for both sexes, followed by Latin America and the Caribbean and the region of central Asia, Middle East and north Africa. Mean WHtR was lowest in central and eastern Europe for both sexes, in the high-income western region for women, and in Oceania for men. Conversely, to achieve an equivalent WHtR, the BMI of the population of south Asia would need to be, on average, 2·79 kg/m² (95% CI 2·31–3·28) lower for women and 1·28 kg/m² (1·02–1·54) lower for men than in the high-income western region. In every region, hypertension prevalence increased with both BMI and WHtR. Models with either of these two adiposity metrics had virtually identical C-statistics and NRIs for every region and sex, with C-statistics ranging from 0·72 to 0·81 and NRIs ranging from 0·34 to 0·57 in different region and sex combinations. When both BMI and WHtR were used, performance improved only slightly compared with using either adiposity measure alone. Interpretation BMI can distinguish young and middle-aged adults with higher versus lower amounts of abdominal adiposity with moderate-to-high accuracy, and both BMI and WHtR distinguish people with or without hypertension. However, at the same BMI level, people in south Asia, Latin America and the Caribbean, and the region of central Asia, Middle East and north Africa, have higher WHtR than in the other regions

Molecular mechanisms of short-term habituation in the leech Hirudo medicinalis

Although habituation is ubiquitous in the animal kingdom, its underlying mechanisms remain poorly understood. In this study, we began to explore the molecular cascades underlying short-term habituation in the leech Hirudo medicinalis. In H. medicinalis, a training paradigm, consisting of low-frequency repetitive electrical stimulation of the skin, produces a gradual increase in the latency to swim that spontaneously recovers within 20–30 min. As first step in determining the molecular pathways in short-term habituation, we examined the role of Ca2+. Both Ca2+ influx through voltage-gated channels and Ca2+ release from intracellular stores were found to contribute to short-term habituation. The analysis of the downstream targets of elevated cytosolic Ca2+ revealed that the activation of the phosholipase A2 was required for the induction of short-term habituation. Finally, we reported that the recruitment of arachidonic acid metabolites, generated by the 5-lipoxygenase pathway, was also necessary for the induction of swim induction habituation. These results provide the framework for a comprehensive characterization of the molecular underpinnings of habituation. This outcome will allow us to compare the mechanisms of habituation with those underlying other forms of nonassociative learning in the leech, such as sensitization and dishabituation, and, more in general, with those governing habituation in different vertebrate and invertebrate model systems

ACETYL-L-CARNITINE AFFECTS NONASSOCIATIVE LEARNING PROCESSES IN THE LEECH HIRUDO MEDICINALIS

Acetyl-L-carnitine is a natural molecule widely dis- tributed in vertebrate and invertebrate nervous system. It is known to have significant effects on neuronal activity playing a role as neuroprotective and anti-nociceptive agent, as well as neuromodulatory factor. About its capability of affecting learning processes the available data are controversial. In the present study, we utilized the simplified model system of the leech Hirudo medicinalis to analyze the effects of acetyl-L-carnitine, assessing whether and how it might affect elementary forms of nonassociative learning processes. In leeches with the head ganglion disconnected from the first segmental ganglion, repetitive application of weak electrical shocks onto the caudal portion of the body wall induces habituation of swim induction whereas brush strokes on the dorsal skin produces sensitization or dishabituation when the nociceptive stimulus is delivered on previously habituated animals. Herein, the effects of different concentrations of acetyl-L-carnitine (2 mM - 0.05 mM) have been tested at different times on both sensitization and dishabituation. The results show that a single treatment of acetyl L-carnitine blocked the onset of sensitization in a dose- and time-dependent manner. In fact, the most effective concentration able to block this process was 2 mM, which induced its major effects 11 days after the treatment, whereas 0.05 mM was unable to affect the sensitization process at all considered time points. On the contrary, acetyl-L-carnitine did not completely abolish dishabituation at the tested concentrations and at every time point. Finally, acetyl-L-carnitine also impaired the habituation of swim induction, but only 11 days after treatment

Risk of long COVID in people infected with severe acute respiratory syndrome coronavirus 2 after 2 doses of a coronavirus disease 2019 vaccine: community-based, matched cohort study

We investigated long COVID incidence by vaccination status in a random sample of UK adults from April 2020 to November 2021. Persistent symptoms were reported by 9.5% of 3090 breakthrough severe acute respiratory syndrome coronavirus 2 infections and 14.6% of unvaccinated controls (adjusted odds ratio, 0.59 [95% confidence interval, .50–.69]), emphasizing the need for public health initiatives to increase population-level vaccine uptake

Risk of Long COVID in People Infected With Severe Acute Respiratory Syndrome Coronavirus 2 After 2 Doses of a Coronavirus Disease 2019 Vaccine: Community-Based, Matched Cohort Study

We investigated long COVID incidence by vaccination status in a random sample of UK adults from April 2020 to November 2021. Persistent symptoms were reported by 9.5% of 3090 breakthrough severe acute respiratory syndrome coronavirus 2 infections and 14.6% of unvaccinated controls (adjusted odds ratio, 0.59 [95% confidence interval, .50-.69]), emphasizing the need for public health initiatives to increase population-level vaccine uptake

Associations between frailty trajectories and cardiovascular, renal, and mortality outcomes in chronic kidney disease

Background Frailty is characterized by the loss of biological reserves and vulnerability to adverse outcomes. In individuals with chronic kidney disease (CKD), numerous pathophysiological factors may be responsible for frailty development including inflammation, physical inactivity, reduced energy intake, and metabolic acidosis. Given that both CKD and frailty incur a significant healthcare burden, it is important to understand the relationship of CKD and frailty in real-world routine clinical practice, and how simple frailty assessment methods (e.g. frailty indexes) may be useful. We investigated the risk of frailty development in CKD and the impact of frailty status on mortality and end-stage kidney disease (ESKD). Methods A retrospective cohort study using primary care records from the Clinical Practice Research Datalink linked to Hospital Episode Statistics and the UK Office for National Statistics was undertaken in 819 893 participants aged ≥40 years, of which 140 674 had CKD. Frailty was defined using an electronic frailty index, generated electronically from primary care records. Cox proportional hazard and flexible parametric survival models were used to investigate the risk of developing frailty and the effect of frailty on risk of all-cause and cardiovascular mortality, and ESKD. Results The mean age of those with CKD was 77.5 (SD 9.7) years [61.0 (SD 12.1) years in no-CKD group]; 62.0% of the CKD group were female (compared with 53.3% in no-CKD group). The mean estimated glomerular filtration rate of those with CKD was 46.1 (SD 9.9) mL/min/1.73 m2. The majority of those with CKD (75.3%) were frail [vs. 45.4% in those without CKD (no-CKD)]. Over 3 years (median), 69.5% of those with CKD developed frailty. Compared with no-CKD, those with CKD had increased rates of developing mild (hazard ratio: 1.02; 95% confidence interval: 1.01–1.04), moderate (1.30; 1.26–1.34), and severe (1.50; 1.37–1.65) frailty. Mild (1.22; 1.19–1.24), moderate (1.60; 1.56–1.63), and severe (2.16; 2.11–2.22) frailty was associated with increased rates of all-cause and cardiovascular-related mortality (mild 1.35; 1.31–1.39; moderate 1.96; 1.90–2.02; and severe 2.91; 2.81–3.02). All stages of frailty significantly increased ESKD rates. Conclusions Frailty is highly prevalent and associated with adverse outcomes in people with CKD, including mortality and risk of ESKD. Preventative interventions should be initiated to mitigate the development of frailty. The use of a simple frailty index, generated electronically from health records, can predict outcomes and may aid prioritization for management of people with frailty.</p

Associations between frailty trajectories and cardiovascular, renal, and mortality outcomes in chronic kidney disease

Background Frailty is characterized by the loss of biological reserves and vulnerability to adverse outcomes. In individuals with chronic kidney disease (CKD), numerous pathophysiological factors may be responsible for frailty development including inflammation, physical inactivity, reduced energy intake, and metabolic acidosis. Given that both CKD and frailty incur a significant healthcare burden, it is important to understand the relationship of CKD and frailty in real-world routine clinical practice, and how simple frailty assessment methods (e.g. frailty indexes) may be useful. We investigated the risk of frailty development in CKD and the impact of frailty status on mortality and end-stage kidney disease (ESKD). Methods A retrospective cohort study using primary care records from the Clinical Practice Research Datalink linked to Hospital Episode Statistics and the UK Office for National Statistics was undertaken in 819 893 participants aged ≥40 years, of which 140 674 had CKD. Frailty was defined using an electronic frailty index, generated electronically from primary care records. Cox proportional hazard and flexible parametric survival models were used to investigate the risk of developing frailty and the effect of frailty on risk of all-cause and cardiovascular mortality, and ESKD. Results The mean age of those with CKD was 77.5 (SD 9.7) years [61.0 (SD 12.1) years in no-CKD group]; 62.0% of the CKD group were female (compared with 53.3% in no-CKD group). The mean estimated glomerular filtration rate of those with CKD was 46.1 (SD 9.9) mL/min/1.73 m2. The majority of those with CKD (75.3%) were frail [vs. 45.4% in those without CKD (no-CKD)]. Over 3 years (median), 69.5% of those with CKD developed frailty. Compared with no-CKD, those with CKD had increased rates of developing mild (hazard ratio: 1.02; 95% confidence interval: 1.01–1.04), moderate (1.30; 1.26–1.34), and severe (1.50; 1.37–1.65) frailty. Mild (1.22; 1.19–1.24), moderate (1.60; 1.56–1.63), and severe (2.16; 2.11–2.22) frailty was associated with increased rates of all-cause and cardiovascular-related mortality (mild 1.35; 1.31–1.39; moderate 1.96; 1.90–2.02; and severe 2.91; 2.81–3.02). All stages of frailty significantly increased ESKD rates. Conclusions Frailty is highly prevalent and associated with adverse outcomes in people with CKD, including mortality and risk of ESKD. Preventative interventions should be initiated to mitigate the development of frailty. The use of a simple frailty index, generated electronically from health records, can predict outcomes and may aid prioritization for management of people with frailty.</p