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 <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For school-aged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >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 obesity.

FUNDING

UK Medical Research Council, UK Research and Innovation (Research England), UK Research and Innovation (Innovate UK), and European Union.

Diminishing benefits of urban living for children and adolescents' growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1-6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5-19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m-2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified.

The quantification of sodium intake from discretionary salt intake in New Zealand using the lithium-tagged salt method

Introduction

Discretionary salt (added in cooking at home or at the table) is a source of sodium and iodine in New Zealand. The amount of discretionary salt consumed in a population has implications on policies regarding sodium and iodine. Sodium intake from discretionary salt intake has not been quantified in New Zealand. The aim of this study was to estimate the proportion of total sodium that comes from discretionary salt in adults using the lithium-tagged salt method.

Methods

A total of 116 healthy adults, who were not pregnant or breastfeeding, regularly consume home-cooked meals and use salt during cooking or at the table, aged 18-40 years from Dunedin, New Zealand were recruited into the study. The study took place over a 9-day period. On Day 1, participants were asked to collect a baseline 24-h urine to establish their normal lithium output. From Day 2 to Day 8, normal discretionary salt was replaced with lithium-tagged salt. Between Day 6 and Day 8, participants collected another two 24-h urine samples. A 24-h dietary recall was conducted to coincide with each of the final two 24-h urine collections. Urinary sodium was analysed by Ion-Selective Electrode and urinary lithium and urinary iodine were analysed using Inductively Coupled Plasma Mass Spectrometry. The 24-h dietary recall data was entered into Xyris FoodWorks 10. All statistical analysis were conducted using Stata 17.0.

Results

A total of 109 participants with complete 24-h urine samples were included in the analysis. From the 24-h urine collections, the median urinary excretion of sodium and iodine was 3,222 mg/24 h (25th, 75th percentile: 2516, 3969) and 112 μg/24 h (82, 134). The median estimated sodium intake from discretionary salt was 13% (25th, 75th percentile: 7, 22) of the total sodium intake or 366 mg/24 h (25th, 75th percentile: 186, 705).

Conclusion

The total sodium intake was higher than the suggested dietary target of 2,000 mg/day. In this sample of healthy adults 18 to 40 years old, 13% of total sodium intake derived from discretionary salt. Discretionary salt is an additional source of iodine if iodised salt is used. Policies to reduce sodium intake is recommended to include a range of strategies to target discretionary and non-discretionary sources of salt and will need to take into account the contribution of iodine from discretionary salt intake.

National Sporting Organisation Policies: A health promotion opportunity?

The objective was to identify whether National Sporting Organisations (NSOs) have policy documentation on healthy behaviours (smokefree, sun-protection, healthy food/beverages, and alcohol) and, for organisations with such documentation, whether this is in-line with current scientific evidence of past best practice in cancer prevention.

METHODS

This cross-sectional policy analysis study was performed September - December 2018 in New Zealand. A content analysis was undertaken using NSO policy documents matched against a framework of key indicators for best practice within health behaviours of interest. Data analysis of the policy process was undertaken through key informant telephone interviews with NSO staff using semi-structured qualitative interviews.

RESULTS

Of 96 NSOs, nearly half (49%) mentioned smokefree at least once in one of their policy documents, and 47% had an alcohol policy, although in both instances the policies lacked comprehensiveness. Two NSOs had a reasonably comprehensive sun protection policy. Seventeen had at least one specific nutrition policy/guideline. The contents of the latter were primarily related to short-term athletic performance rather than non-communicable disease prevention, specifically promoting hydration during sports participation, and food and nutrition to support sporting performance. Two NSOs had policies relating to the promotion of health food/nutrition more widely. For some NSOs the lack of health-related policies was not a conscious choice but just not considered previously. Other NSOs reported they lacked resources or had other priorities.

CONCLUSIONS

Although this study clearly demonstrates that many NSOs lack adequate health-related policies, this is not necessarily a conscious choice, but the result of a lack of resources, other priorities, or just that they had not considered developing policies in these areas. A number expressed support for these types of policies although it was apparent that some, particularly smaller NSOs would require assistance in policy template development. It seems probable that the development of health-related policies will only occur if partner agencies become involved.

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

BACKGROUND

Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories.

METHODS

We used data from 1990 to 2019 on people aged 30-79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age.

FINDINGS

The number of people aged 30-79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306-359) million women and 317 (292-344) million men in 1990 to 626 (584-668) million women and 652 (604-698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55-62) of women and 49% (46-52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43-51) of women and 38% (35-41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20-27) for women and 18% (16-21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran.

INTERPRETATION

Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings.

FUNDING

WHO.

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions.

Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

BACKGROUND

Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents.

METHODS

For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5-19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence.

FINDINGS

We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9-10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes-gaining too little height, too much weight for their height compared with children in other countries, or both-occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls.

INTERPRETATION

The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks.

FUNDING

Wellcome Trust, AstraZeneca Young Health Programme, EU.

Repositioning of the global epicentre of non-optimal cholesterol

High blood cholesterol is typically considered a feature of wealthy western countries1,2. However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world3 and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health4,5. However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol-which is a marker of cardiovascular risk-changed from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million-4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.

National trends in total cholesterol obscure heterogeneous changes in HDL and non-HDL cholesterol and total-to-HDL cholesterol ratio: a pooled analysis of 458 population-based studies in Asian and Western countries

BACKGROUND

Although high-density lipoprotein (HDL) and non-HDL cholesterol have opposite associations with coronary heart disease, multi-country reports of lipid trends only use total cholesterol (TC). Our aim was to compare trends in total, HDL and non-HDL cholesterol and the total-to-HDL cholesterol ratio in Asian and Western countries.

METHODS

We pooled 458 population-based studies with 82.1 million participants in 23 Asian and Western countries. We estimated changes in mean total, HDL and non-HDL cholesterol and mean total-to-HDL cholesterol ratio by country, sex and age group.

RESULTS

Since ∼1980, mean TC increased in Asian countries. In Japan and South Korea, the TC rise was due to rising HDL cholesterol, which increased by up to 0.17 mmol/L per decade in Japanese women; in China, it was due to rising non-HDL cholesterol. TC declined in Western countries, except in Polish men. The decline was largest in Finland and Norway, at ∼0.4 mmol/L per decade. The decline in TC in most Western countries was the net effect of an increase in HDL cholesterol and a decline in non-HDL cholesterol, with the HDL cholesterol increase largest in New Zealand and Switzerland. Mean total-to-HDL cholesterol ratio declined in Japan, South Korea and most Western countries, by as much as ∼0.7 per decade in Swiss men (equivalent to ∼26% decline in coronary heart disease risk per decade). The ratio increased in China.

CONCLUSIONS

HDL cholesterol has risen and the total-to-HDL cholesterol ratio has declined in many Western countries, Japan and South Korea, with only a weak correlation with changes in TC or non-HDL cholesterol.

Science of Salt: A regularly updated systematic review of salt and health outcomes studies (April to October 2018)

The Science of Salt reviews identify, summarize, and critically appraise published studies on dietary salt and health outcomes according to pre-specified methods. This review covers the period April 3 to October 30, 2018. Here, nineteen studies that fit pre-specified criteria for review and summary are included. Three of these, one prospective cohort study, one randomized controlled trial, and a post hoc analysis of the Dietary Approaches to Stop Hypertension (DASH) sodium trial fulfilled the quality criteria for detailed critical appraisal, including risk of bias assessment, and commentary. Two trials demonstrated a positive association between salt intake and blood pressure. In a cohort of older Italians, increased risk of total mortality was observed with salt intake less than ~16 g/d (6300 mg sodium/d) at baseline; no association existed for incident cardiovascular disease (CVD) or CVD mortality. The paucity of published studies which met our criteria for methodological quality is of concern.

Twenty-Four-Hour Diet recall and Diet records compared with 24-hour urinary excretion to predict an individual's sodium consumption: A Systematic Review

This systematic literature review aimed to investigate whether 24 hour diet recall and diet records are reliable and valid ways to measure usual dietary sodium intake compared with 24 hour urinary assessment. We searched electronic databases Medline, Embase, Cinahl, Lilacs, Google Scholar and the Cochrane Library using pre-defined terms Studies were eligible for inclusion if they assessed adult humans in free-living settings, and if they included dietary assessment and 24 hours urinary collection for assessment of sodium intake in the same participants. Studies that included populations with an active disease state that might interfere with normal sodium metabolism were excluded. Results of 20 studies using 24 hour diet recall recall (including 14 validation studies) and 10 studies using food records (including six validation studies) are included in this review. Correlations between estimates from dietary assessment and urinary excretion ranged from 0.16 to 0.72 for 24 hour diet recall, and 0.11 to 0.49 for food diaries. Bland-Altman analysis in two studies of 24 hour diet recall showed poor agreement with 24 hours urinary sodium excretion. These results show that 24 hour diet recall and diet records inaccurately measure dietary sodium intake in individuals compared with the gold standard 24 hours urinary excretion. Validation studies of dietary assessment methods should include multiple days of assessment and 24 hours urine collection, use relevant food composition databases and Bland-Altman methods of analysis.

Impact of a Modified Version of Baby-Led Weaning on Infant Food and Nutrient Intakes: The BLISS Randomized Controlled Trial

Despite growing international interest in Baby-Led Weaning (BLW), we know almost nothing about food and nutrient intake in infants following baby-led approaches to infant feeding. The aim of this paper was to determine the impact of modified BLW (i.e., Baby-Led Introduction to SolidS; BLISS) on food and nutrient intake at 7–24 months of age. Two hundred and six women recruited in late pregnancy were randomized to Control (n = 101) or BLISS (n = 105) groups. All participants received standard well-child care. BLISS participants also received lactation consultant support to six months, and educational sessions about BLISS (5.5, 7, and 9 months). Three-day weighed diet records were collected for the infants (7, 12, and 24 months). Compared to the Control group, BLISS infants consumed more sodium (percent difference, 95% CI: 35%, 19% to 54%) and fat (6%, 1% to 11%) at 7 months, and less saturated fat (−7%, −14% to −0.4%) at 12 months. No differences were apparent at 24 months of age but the majority of infants from both groups had excessive intakes of sodium (68% of children) and added sugars (75% of children). Overall, BLISS appears to result in a diet that is as nutritionally adequate as traditional spoon-feeding, and may address some concerns about the nutritional adequacy of unmodified BLW. However, BLISS and Control infants both had high intakes of sodium and added sugars by 24 months that are concerning.

Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: a pooled analysis of 1018 population-based measurement studies with 88.6 million participants

BACKGROUND

Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure.

METHODS

We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probit-transformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure.

RESULTS

In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the high-income Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association.

CONCLUSIONS

Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups.

Spot urine and 24-h diet recall estimates of dietary sodium intake from the 2008/09 New Zealand Adult Nutrition Survey: a comparison

BACKGROUND

We aimed to test the difference between estimates of dietary sodium intake using 24-h diet recall and spot urine collection in a large sample of New Zealand adults.

METHODS

We analysed spot urine results, 24-h diet recall, dietary habits questionnaire and anthropometry from a representative sample of 3312 adults aged 15 years and older who participated in the 2008/09 New Zealand Adult Nutrition Survey. Estimates of adult population sodium intake were derived from 24-h diet recall and spot urine sodium using a formula derived from analysis of INTERSALT data. Correlations, limits of agreement and mean difference were calculated for the total sample, and for population subgroups.

RESULTS

Estimated total population 24-h urinary sodium excretion (mean (95% CI)) from spot urine samples was 3035 mg (2990, 3079); 3612 mg (3549, 3674) for men and 2507 mg (2466, 2548) for women. Estimated mean usual daily sodium intake from 24-h diet recall data (excluding salt added at the table) was 2564 mg (2519, 2608); 2849 mg (2779, 2920) for men and 2304 mg (2258, 2350) for women. Correlations between estimates were poor, especially for men, and limits of agreement using Bland-Altman mean difference analysis were wide.

CONCLUSIONS

There is a poor agreement between estimates of individual sodium intake from spot urine collection and those from 24-hour diet recall. Although, both 24-hour dietary recall and estimated urinary excretion based on spot urine indicate mean population sodium intake is greater than 2 g, significant differences in mean intake by method deserve further investigation in relation to the gold standard, 24-hour urinary sodium excretion.

Worldwide trends in body-mass index, underweight, overweight, and obesity from 1975 to 2016: a pooled analysis of 2416 population-based measurement studies in 128·9 million children, adolescents, and adults

BACKGROUND

Underweight, overweight, and obesity in childhood and adolescence are associated with adverse health consequences throughout the life-course. Our aim was to estimate worldwide trends in mean body-mass index (BMI) and a comprehensive set of BMI categories that cover underweight to obesity in children and adolescents, and to compare trends with those of adults.

METHODS

We pooled 2416 population-based studies with measurements of height and weight on 128·9 million participants aged 5 years and older, including 31·5 million aged 5-19 years. We used a Bayesian hierarchical model to estimate trends from 1975 to 2016 in 200 countries for mean BMI and for prevalence of BMI in the following categories for children and adolescents aged 5-19 years: more than 2 SD below the median of the WHO growth reference for children and adolescents (referred to as moderate and severe underweight hereafter), 2 SD to more than 1 SD below the median (mild underweight), 1 SD below the median to 1 SD above the median (healthy weight), more than 1 SD to 2 SD above the median (overweight but not obese), and more than 2 SD above the median (obesity).

FINDINGS

Regional change in age-standardised mean BMI in girls from 1975 to 2016 ranged from virtually no change (-0·01 kg/m2 per decade; 95% credible interval -0·42 to 0·39, posterior probability [PP] of the observed decrease being a true decrease=0·5098) in eastern Europe to an increase of 1·00 kg/m2 per decade (0·69-1·35, PP>0·9999) in central Latin America and an increase of 0·95 kg/m2 per decade (0·64-1·25, PP>0·9999) in Polynesia and Micronesia. The range for boys was from a non-significant increase of 0·09 kg/m2 per decade (-0·33 to 0·49, PP=0·6926) in eastern Europe to an increase of 0·77 kg/m2 per decade (0·50-1·06, PP>0·9999) in Polynesia and Micronesia. Trends in mean BMI have recently flattened in northwestern Europe and the high-income English-speaking and Asia-Pacific regions for both sexes, southwestern Europe for boys, and central and Andean Latin America for girls. By contrast, the rise in BMI has accelerated in east and south Asia for both sexes, and southeast Asia for boys. Global age-standardised prevalence of obesity increased from 0·7% (0·4-1·2) in 1975 to 5·6% (4·8-6·5) in 2016 in girls, and from 0·9% (0·5-1·3) in 1975 to 7·8% (6·7-9·1) in 2016 in boys; the prevalence of moderate and severe underweight decreased from 9·2% (6·0-12·9) in 1975 to 8·4% (6·8-10·1) in 2016 in girls and from 14·8% (10·4-19·5) in 1975 to 12·4% (10·3-14·5) in 2016 in boys. Prevalence of moderate and severe underweight was highest in India, at 22·7% (16·7-29·6) among girls and 30·7% (23·5-38·0) among boys. Prevalence of obesity was more than 30% in girls in Nauru, the Cook Islands, and Palau; and boys in the Cook Islands, Nauru, Palau, Niue, and American Samoa in 2016. Prevalence of obesity was about 20% or more in several countries in Polynesia and Micronesia, the Middle East and north Africa, the Caribbean, and the USA. In 2016, 75 (44-117) million girls and 117 (70-178) million boys worldwide were moderately or severely underweight. In the same year, 50 (24-89) million girls and 74 (39-125) million boys worldwide were obese.

INTERPRETATION

The rising trends in children's and adolescents' BMI have plateaued in many high-income countries, albeit at high levels, but have accelerated in parts of Asia, with trends no longer correlated with those of adults.

FUNDING

Wellcome Trust, AstraZeneca Young Health Programme.

Urinary iodine concentration of New Zealand adults improves with mandatory fortification of bread with iodised salt but not to predicted levels

PURPOSE

To measure the iodine status and iodine intake of New Zealand adults 18-64 years of age following mandatory fortification of bread with iodine.

METHODS

A cross-sectional survey of NZ adults living in Dunedin and Wellington during February-November 2012. Three hundred and one men and women aged 18-64 years randomly selected from the New Zealand Electoral Roll completed a 24-h urine collection, a demographic and iodine-specific food frequency questionnaire (FFQ), and had height and weight measured. Urine collections were analysed for iodine and reported as median urinary iodine concentration (UIC) µg/L and median urinary iodine excretion (UIE) µg/day. The FFQ was used to estimate iodine intake with and without discretionary iodised salt use.

RESULTS

The median UIC for all adults was 73 µg/L, indicative of mild iodine deficiency. The mean urinary volume was 2.0 L. As an estimate of iodine intake, the median UIE was 127 µg/day. Estimated iodine intake, using the FFQ which included discretionary iodised salt use, was 132 µg/day. Iodine intakes were associated with UIC (P = 0.040) and UIE (P = 0.003), but not with bread iodine intake and iodised salt use.

CONCLUSION

Using the WHO/UNICEF/ICCIDD target for iodine sufficiency (a UIC of >100 µg/L) based on school-aged children with a mean urinary volume of 1.0 L, the iodine status of NZ adults does not reach adequate levels (73 µg/L). A more realistic parameter in a population with a higher urinary volume excretion (2.0 L) is the UIE. A median UIE of 127 µg/day suggests that the iodine status of NZ adults is now likely to be adequate.

Measuring population sodium intake: a review of methods

Reduction of population sodium intake has been identified as a key initiative for reduction of Non-Communicable Disease. Monitoring of population sodium intake must accompany public health initiatives aimed at sodium reduction. A number of different methods for estimating dietary sodium intake are currently in use. Dietary assessment is time consuming and often under-estimates intake due to under-reporting and difficulties quantifying sodium concentration in recipes, and discretionary salt. Twenty-four hour urinary collection (widely considered to be the most accurate method) is also burdensome and is limited by under-collection and lack of suitable methodology to accurately identify incomplete samples. Spot urine sampling has recently been identified as a convenient and affordable alternative, but remains highly controversial as a means of monitoring population intake. Studies suggest that while spot urinary sodium is a poor predictor of 24-h excretion in individuals, it may provide population estimates adequate for monitoring. Further research is needed into the accuracy and suitability of spot urine collection in different populations as a means of monitoring sodium intake.

Blood pressure and hypertension in New Zealand: results from the 2008/09 Adult Nutrition Survey

AIMS

To report the blood pressure results from the 2008/09 New Zealand Adult Nutrition Survey (2008/09NZANS).

METHODS

Blood pressure measurements were available for 4,407 adults who were part of a survey involving face-to-face interviews with 4,721 New Zealanders aged 15 years and over. Three measurements were taken one minute apart, and the mean of the second and third readings has been used for this analysis. Hypertension was defined as systolic blood pressure (SBP) greater than and equal to 140 mmHg or diastolic blood pressure (DBP) greater than and equal to 90 mmHg or self reported use of antihypertensive medications. Comparisons were made with previously published New Zealand population blood pressure estimates.

RESULTS

Mean SBP for the New Zealand adult population was 126 mmHg. The prevalence of hypertension was 31%, with 15% reporting taking antihypertensive medication. Mean SBP has increased since 2002/03 for New Zealand European and others (NZEO) aged 35-54 years and Maori aged 35-74 years, reversing a downward trend observed in NZEO between 1982 and 2002.

CONCLUSIONS

The increasing blood pressure levels are concerning. Given the importance of elevated blood pressure as a risk factor for cardiovascular disease, intensive screening, public health measures aimed at lowering population blood pressure, and further population monitoring are warranted.

World Salt Awareness Week: more action needed in New Zealand

World Salt Awareness Week ran from 21 to 27 March 2011. Increasing attention to the detrimental health effects of a high dietary salt intake has led to substantial public health campaigns in the United Kingdom, New York, Finland, Japan, and Canada. Indeed, recent modelling indicates that salt reduction is likely to be one of the most cost-effective population public health interventions for chronic disease reduction available.

"Healthy Eating - Healthy Action": evaluating New Zealand's obesity prevention strategy

BACKGROUND

New Zealand rates of obesity and overweight have increased since the 1980s, particularly among indigenous Māori people, Pacific people and those living in areas of high deprivation. New Zealand's response to the obesity epidemic has been The Healthy Eating-Healthy Action: Oranga Kai - Oranga Pumau (HEHA) Strategy ('the Strategy'), launched in 2003. Because the HEHA Strategy explicitly recognises the importance of evaluation and the need to create an evidence base to support future initiatives, the Ministry of Health has commissioned a Consortium of researchers to evaluate the Strategy as a whole.

METHODS

This paper discusses the Consortium's approach to evaluating the HEHA Strategy. It includes an outline of the conceptual framework underpinning the evaluation, and describes the critical components of the evaluation which are: judging to what extent stakeholders were engaged in the process of the strategy implementation and to what extent their feedback was incorporated in to future iterations of the Strategy (continuous improvement), to what extent the programmes, policies, and initiatives implemented span the target populations and priority areas, whether there have been any population changes in nutrition and/or physical activity outcomes or behaviours relating to those outcomes, and to what extent HEHA Strategy and spending can be considered value for money.

DISCUSSION

This paper outlines our approach to evaluating a complex national health promotion strategy. Not only does the Evaluation have the potential to identify interventions that could be adopted internationally, but also the development of the Evaluation design can inform other complex evaluations.

Life-threatening clozapine-induced gastrointestinal hypomotility: an analysis of 102 cases

OBJECTIVE

To raise awareness of potentially lethal clozapine-induced gastrointestinal hypomotility (CIGH) by reviewing cases from the literature and unpublished pharmacovigilance data and to offer strategies aimed at prevention and early treatment.

METHOD

Databases (PsycINFO, 1967-2007; MEDLINE, 1950-2007; and EMBASE, 1988-2007) were searched using the term clozapine together with each of the following: gastrointestinal, dysmotility, constipation, obstipation, fecal impaction, fecaloma, paralytic ileus, adynamic ileus, subileus, ischemic colitis, colon ischemia, bowel ischemia, gastrointestinal ischemia, gut ischemia, obstruction, necrosis, gangrene, bowel perforation, micro-perforation, megacolon, toxic megacolon, acquired megacolon, pseudo-obstruction, Ogilvie, and Ogilvie's syndrome. We analyzed the electronic database entries held by the Adverse Drug Reactions Advisory Committee and the New Zealand Intensive Medicines Monitoring Program, which cited suspected clozapine-related gastrointestinal side effects, as well as all relevant published case reports. We reviewed the literature on the treatment of gastrointestinal hypomotility and constipation.

RESULTS

We compiled a database of 102 cases of suspected life-threatening CIGH. There was a mortality rate of 27.5% and considerable morbidity, largely due to bowel resection. Within Australasia, at least 15 patients have died of CIGH. Probable risk factors are identified as recent instigation of clozapine, high clozapine dose or serum level, concomitant anticholinergic use, or intercurrent illness.

CONCLUSION

The paucity of literature on CIGH suggests that the significance of this uncommon but important and frequently fatal side effect has not been recognized. Clozapine can affect the entire gastrointestinal system, from esophagus to rectum, and may cause bowel obstruction, ischemia, perforation, and aspiration. The mechanism is likely to be anticholinergic and antiserotonergic. Clozapine prescribing should be accompanied by regular physical monitoring, appropriate and timely use of laxatives, and early referral of constipated patients--before life-threatening pathologic processes develop.

Alopecia associated with quetiapine

Alopecia has previously been reported with the atypical antipsychotic medicines olanzapine and risperidone, but has not been described with quetiapine. Case reports of alopecia associated with quetiapine reported to the New Zealand Intensive Medicines Monitoring Programme were reviewed. The World Health Organization international spontaneous reporting database was also searched for additional case reports. Literature searches were conducted for previous reports of alopecia associated with quetiapine. The Intensive Medicines Monitoring Programme database included two case reports of alopecia associated with quetiapine. Assessment of these cases suggested a causal relationship with the medicine. The World Health Organization international database included a further 15 case reports, providing evidence supporting this association. No previously published reports of alopecia associated with quetiapine were identified. In conclusion, these are the first published case reports of alopecia associated with quetiapine.

Anticardiolipin antibodies in the polymyalgia rheumatica-temporal arteritis syndromes

A series of seven patients with the polymyalgia rheumatica-temporal arteritis (PMR-TA) complex is presented, each of whom during the clinical course demonstrated the presence of anticardiolipin antibodies (ACLs). Presenting symptoms consisted of proximal myalgias and stiffness characteristic of PMR in five patients and of visual symptoms and headache suspicious for TA in two patients. Two of the five PMR patients later developed jaw claudication characteristic of TA. Six of the seven cases demonstrated clinical evidence of a vasculopathic process such as a cerebrovascular infarct or a vasculitic syndrome. Previous studies have suggested an association between ACLs and PMR-TA, and this series of patients appears to provide more supporting evidence. Even patients who only manifested PMR symptoms without suggestion of accompanying TA developed vascular complications. An increasing range of symptoms have been recognized in association with ACLs, and the vasculitic syndromes of PMR-TA should be included as a possible association. While this series together with previous studies may suggest that the presence of ACLs in patients with PMR-TA symptoms may serve as a marker for the development of vascular complications, larger longitudinal studies will be necessary in the future.

Bone and joint manifestations of hypothyroidism

Hypothyroidism is frequently accompanied by musculoskeletal manifestations ranging from myalgias and arthralgias to true myopathy and arthritis. A case is presented in which an arthropathic process in the hip was the isolated finding in a young man who was severely hypothyroid. Previous literature on bone and joint manifestations of hypothyroidism is reviewed, with emphasis on cases where such manifestations were the presenting symptoms of thyroid dysfunction. Most cases of arthropathic changes in adult-recognized hypothyroidism involved the knees and hands, while the hip and the epiphysis of the femoral head appear more commonly involved in children. Thyroid hormones have known effects at the cellular level on proliferation and differentiation of bone and cartilage. The hypothyroid state appears to induce abnormalities in these tissues, which result in such clinical manifestations as epiphyseal dysgenesis, aseptic necrosis, possibly crystal-induced arthritis, and an arthropathy characterized by highly viscous noninflammatory joint effusions primarily affecting the knees, wrists, and hands. Neuropathic and myopathic symptoms accompanying hypothyroidism may manifest as joint region abnormalities when in fact there is no underlying arthropathy.

Magnesium and its therapeutic uses: a review

Magnesium has been reported as an effective medical therapy in an expanding array of conditions. Evidence investigating magnesium's use is presented, with a number of studies suggesting it should be seriously considered in such conditions as ischemic heart disease, cardiac arrhythmias, and asthma. Magnesium balance and metabolism are briefly reviewed, and then various hypotheses are presented that may explain magnesium's physiologic mechanisms of action, most likely involving calcium and potassium flux across cellular membranes in smooth muscle. In a number of the conditions to be discussed, it has been uncertain whether magnesium administration serves the purpose of merely correcting an underlying deficiency state or of utilizing a specific pharmacologic effect of magnesium. Magnesium deficiency is a relatively common condition, and predisposing factors as well as recent methods for assessing total body stores of magnesium are discussed. Physicians should be familiar with the numerous conditions and therapeutics that are risk factors for an underlying magnesium deficiency and in which empiric magnesium replacement should be considered. Guidelines for administration of parenteral magnesium are presented with specific focus on the low risk of adverse effects, as suggested by the large and rapid dosing regimens used in many of the clinical studies discussed here.

Investigations on the origin and metabolism of the carbon skeleton of ornithine, arginine and proline in selected animals

The origin and metabolism of the carbon skeletons of the amino acids ornithine and arginine have been investigated in selected animals--an earthworm, an edible mollusc, a starfish, a sea-squirt, a freshwater crustacean and a rat. Only in the rat and microorganisms of sea water was any evidence obtained for the conversion of glutamate (or N-acetylglutamate) to ornithine. Apart from the crustacean, the other animals were able to synthesise the amidine moiety of arginine. All animals were able to hydrolyse (arginase) the amidine moiety from arginine and had the enzymic capacity to convert ornithine to proline. All the animals had some enzymic ability to oxidise proline to pyrroline-5-carboxylic acid. The crustacean (Cherax destructor) was able to conserve the high concentrations of arginine in its tail muscles during fasting. The hypothesis is put forward that, as arginine appears to be an essential amino acid in the diet of this animal, its demonstrated cannibalism is, among other things, a way of supplementing dietary arginine. The results are discussed in relation to the evolution of different phosphagens derived from arginine.

Synthesis of phosphocreatine and phosphoarginine by mitochondria from various sources

Mitochondria from heart, skeletal muscle and the liver of the rat have been shown to synthesise phosphoarginine through ATP if supplied with arginine and lobster arginine kinase. Liver mitochondria have been shown to synthesise phosphocreatine through ATP with the aid of the cytosolic isomer of creatine kinase. Mitochondria prepared from muscles of a crustacean, a fish and a bird have been shown oxidatively to synthesise phosphocreatine (crustacean) and phosphoarginine (fish and bird) provided they are supplied with the appropriate kinase and catalytic amounts of ATP. Within one second of the addition of either cytosolic kinases, mitochondria from skeletal muscle and liver begin a steady state synthesis of phosphoarginine or phosphocreatine. The results suggest that, with respect to phosphagen synthesis, the addition of the cytosolic enzymes can substitute for the mitochondrial enzyme. It is difficult therefore to accept a special vectorial function for the bound mitochondrial enzyme at the biological concentrations of ATP and the cytosolic enzymes normally associated with phosphagen synthesis.

On the possible significance of the transamidination reaction in evolution

The origin of the various muscle phosphagens during evolution is considered in the context of the need to conserve ornithine for the synthesis of proline for connective tissue necessary for structural strength and flexibility and/or a complicated musculature. In each phosphagen, arginine is known to have contributed its amidine moiety thus maintaining the function of the phosphagen and setting free the proline precursor ornithine. Tissues from an earthworm, a starfish and a sea-squirt have been found to contain the enzymes arginase, ornithine aminotransferase and pyrroline-5-carboxylate reductase which are necessary to convert arginine to proline. For each of the animals studied analysis for the relevant free amino acids and for the characteristic amino acids (Pro, Oh-Pro, Oh-Lys, Gly) of collagen are presented. The amino acid composition of the diet of the sea-squirt Pyura stolonifera and of the starfish Coscinasterias calamaria is presented along with the level of the phosphagen kinases of the animals studied. The significance of the experimental results is discussed in connection with the importance of the transamidination reaction.

A study of the plasma lipoproteins and the tissue lipids of the migrating lamprey, Mordacia mordax

Sea lampreys, Mordacia mordax, were collected in spring from the Yarra River, Victoria, during their upstream spawning migration, to study the lipid composition in their tissues and plasma and their lipid transport system. Plasma lipoproteins were isolated by preparative ultracentrifugation and their chemical compositions were analyzed. The major classes of lipoproteins were found to be similar to those of man and higher animals. Lipids from the muscle and liver were analyzed for fatty acids. The striking feature of the lipids in the migrating lamprey is the presence of very high levels of cholesterol in both plasma and muscle. The possible metabolic roles of cholesterol have been discussed.