Cervical cancer screening programmes and age-specific coverage estimates for 202 countries and territories worldwide: a review and synthetic analysis.

BACKGROUND: Cervical cancer screening coverage is a key monitoring indicator of the WHO cervical cancer elimination plan. We present global, regional, and national cervical screening coverage estimates against the backdrop of the 70% coverage target set by WHO. METHODS: In this review and synthetic analysis, we searched scientific literature, government websites, and official documentation to identify official national recommendations and coverage data for cervical cancer screening for the 194 WHO member states and eight associated countries and territories published from database inception until Oct 30, 2020, supplemented with a formal WHO country consultation from Nov 27, 2020, to Feb 12, 2021. We extracted data on the year of introduction of recommendations, the existence of individual invitation to participate, financing of screening tests, primary screening and triage tests used, recommended ages and screening intervals, use of self-sampling, and use of screen-and-treat approaches. We also collected coverage data, either administrative or survey-based, as disaggregated as possible by age and for any available screening interval. According to data completeness and representativeness, different statistical models were developed to produce national age-specific coverages by screening interval, which were transformed into single-age datapoints. Missing data were imputed. Estimates were applied to the 2019 population and aggregated by region and income level. FINDINGS: We identified recommendations for cervical screening in 139 (69%) of 202 countries and territories. Cytology was the primary screening test in 109 (78%) of 139 countries. 48 (35%) of 139 countries recommended primary HPV-based screening. Visual inspection with acetic acid was the most recommended test in resource-limited settings. Estimated worldwide coverage in women aged 30-49 years in 2019 was 15% in the previous year, 28% in the previous 3 years, and 32% in the previous 5 years, and 36% ever in lifetime. An estimated 1·6 billion (67%) of 2·3 billion women aged 20-70 years, including 662 million (64%) of 1·0 billion women aged 30-49 years, had never been screened for cervical cancer. 133 million (84%) of 158 million women aged 30-49 years living in high-income countries had been screened ever in lifetime, compared with 194 million (48%) of 404 million women in upper-middle-income countries, 34 million (9%) of 397 million women in lower-middle-income countries, and 8 million (11%) of 74 million in low-income countries. INTERPRETATION: Two in three women aged 30-49 years have never been screened for cervical cancer. Roll-out of screening is very low in low-income and middle-income countries, where the burden of disease is highest. The priority of the WHO elimination campaign should be to increase both screening coverage and treatment of detected lesions; however, expanding the efforts of surveillance systems in both coverage and quality control are major challenges to achieving the WHO elimination target. FUNDING: Instituto de Salud Carlos III, European Regional Development Fund, Secretariat for Universities and Research of the Department of Business and Knowledge of the Government of Catalonia, and Horizon 2020. TRANSLATIONS: For the French, Spanish translations of the abstract see Supplementary Materials section.

Levels of domain-specific physical activity at work, in the household, for travel and for leisure among 327 789 adults from 104 countries.

OBJECTIVE: To compare the country-level absolute and relative contributions of physical activity at work and in the household, for travel, and during leisure-time to total moderate-to-vigorous physical activity (MVPA). METHODS: We used data collected between 2002 and 2019 from 327 789 participants across 104 countries and territories (n=24 low, n=34 lower-middle, n=30 upper-middle, n=16 high-income) from all six World Health Organization (WHO) regions. We calculated mean min/week of work/household, travel and leisure MVPA and compared their relative contributions to total MVPA using Global Physical Activity Questionnaire data. We compared patterns by country, sex and age group (25-44 and 45-64 years). RESULTS: Mean MVPA in work/household, travel and leisure domains across the 104 countries was 950 (IQR 618-1198), 327 (190-405) and 104 (51-131) min/week, respectively. Corresponding relative contributions to total MVPA were 52% (IQR 44%-63%), 36% (25%-45%) and 12% (4%-15%), respectively. Work/household was the highest contributor in 80 countries; travel in 23; leisure in just one. In both absolute and relative terms, low-income countries tended to show higher work/household (1233 min/week, 57%) and lower leisure MVPA levels (72 min/week, 4%). Travel MVPA duration was higher in low-income countries but there was no obvious pattern in the relative contributions. Women tended to have relatively less work/household and more travel MVPA; age groups were generally similar. CONCLUSION: In the largest domain-specific physical activity study to date, we found considerable country-level variation in how MVPA is accumulated. Such information is essential to inform national and global policy and future investments to provide opportunities to be active, accounting for country context.

National palliative care capacities around the world: Results from the World Health Organization Noncommunicable Disease Country Capacity Survey.

BACKGROUND: Previous estimates of global palliative care development have not been based on official country data. AIM: The World Health Organization Noncommunicable Disease Country Capacity Survey of World Health Organization member state officials monitors countries' capacities for the prevention and control of noncommunicable diseases. In 2015, for the first time, questions were included on a number of palliative care development metrics to generate baseline data for monitoring global palliative care development. DESIGN: Participants were given instructions, a glossary of terms, and 3 months to complete this closed, non-randomized, online survey. Questions were developed through a consultative process with relevant technical World Health Organization departments. SETTING/PARTICIPANTS: Health ministry officials serving as noncommunicable disease focal points from 177 out of 194 (91%) of World Health Organization Member States completed the voluntary survey. RESULTS: This survey reveals that (a) a minority (37%) of countries have an operational national policy for noncommunicable diseases that includes palliative care, (b) palliative care is least likely to have funding available compared with other core noncommunicable disease services, and (c) there is a large country-income gradient for palliative care funding, oral morphine availability, and integration of palliative care services at the primary levels of the health system. CONCLUSION: Palliative care for noncommunicable disease patients must be strengthened in a majority of countries. These data provide a baseline for trend measurement of official country-level and global palliative care development. A repeat assessment is taking place in the first half of 2017.

The World Health Organization STEPwise Approach to Noncommunicable Disease Risk-Factor Surveillance: Methods, Challenges, and Opportunities.

OBJECTIVES: We sought to outline the framework and methods used by the World Health Organization (WHO) STEPwise approach to noncommunicable disease (NCD) surveillance (STEPS), describe the development and current status, and discuss strengths, limitations, and future directions of STEPS surveillance. METHODS: STEPS is a WHO-developed, standardized but flexible framework for countries to monitor the main NCD risk factors through questionnaire assessment and physical and biochemical measurements. It is coordinated by national authorities of the implementing country. The STEPS surveys are generally household-based and interviewer-administered, with scientifically selected samples of around 5000 participants. RESULTS: To date, 122 countries across all 6 WHO regions have completed data collection for STEPS or STEPS-aligned surveys. CONCLUSIONS: STEPS data are being used to inform NCD policies and track risk-factor trends. Future priorities include strengthening these linkages from data to action on NCDs at the country level, and continuing to develop STEPS' capacities to enable a regular and continuous cycle of risk-factor surveillance worldwide.

Short Maternal Stature Increases Risk of Small-for-Gestational-Age and Preterm Births in Low- and Middle-Income Countries: Individual Participant Data Meta-Analysis and Population Attributable Fraction.

BACKGROUND: Small-for-gestational-age (SGA) and preterm births are associated with adverse health consequences, including neonatal and infant mortality, childhood undernutrition, and adulthood chronic disease. OBJECTIVES: The specific aims of this study were to estimate the association between short maternal stature and outcomes of SGA alone, preterm birth alone, or both, and to calculate the population attributable fraction of SGA and preterm birth associated with short maternal stature. METHODS: We conducted an individual participant data meta-analysis with the use of data sets from 12 population-based cohort studies and the WHO Global Survey on Maternal and Perinatal Health (13 of 24 available data sets used) from low- and middle-income countries (LMIC). We included those with weight taken within 72 h of birth, gestational age, and maternal height data (n = 177,000). For each of these studies, we individually calculated RRs between height exposure categories of < 145 cm, 145 to < 150 cm, and 150 to < 155 cm (reference: ≥ 155 cm) and outcomes of SGA, preterm birth, and their combination categories. SGA was defined with the use of both the International Fetal and Newborn Growth Consortium for the 21st Century (INTERGROWTH-21st) birth weight standard and the 1991 US birth weight reference. The associations were then meta-analyzed. RESULTS: All short stature categories were statistically significantly associated with term SGA, preterm appropriate-for-gestational-age (AGA), and preterm SGA births (reference: term AGA). When using the INTERGROWTH-21st standard to define SGA, women < 145 cm had the highest adjusted risk ratios (aRRs) (term SGA-aRR: 2.03; 95% CI: 1.76, 2.35; preterm AGA-aRR: 1.45; 95% CI: 1.26, 1.66; preterm SGA-aRR: 2.13; 95% CI: 1.42, 3.21). Similar associations were seen for SGA defined by the US reference. Annually, 5.5 million term SGA (18.6% of the global total), 550,800 preterm AGA (5.0% of the global total), and 458,000 preterm SGA (16.5% of the global total) births may be associated with maternal short stature. CONCLUSIONS: Approximately 6.5 million SGA and/or preterm births in LMIC may be associated with short maternal stature annually. A reduction in this burden requires primary prevention of SGA, improvement in postnatal growth through early childhood, and possibly further intervention in late childhood and adolescence. It is vital for researchers to broaden the evidence base for addressing chronic malnutrition through multiple life stages, and for program implementers to explore effective, sustainable ways of reaching the most vulnerable populations.

The Burden and Determinants of Non Communicable Diseases Risk Factors in Nepal: Findings from a Nationwide STEPS Survey.

BACKGROUND: World Health Organization (WHO) estimates for deaths attributed to Non Communicable Diseases (NCDs) in Nepal have risen from 51% in 2010 to 60% in 2014. This study assessed the distribution and determinants of NCD risk factors among the Nepalese adult population. METHODS AND FINDINGS: A nationally representative cross-sectional survey was conducted from Jan to June 2013 on the prevalence of NCD risk factors using the WHO NCD STEPS instrument. A multistage cluster sampling method was used to randomly select the 4,200 respondents. The adjusted prevalence ratio (APR) was used to assess the determinants of NCD risk factors using a Poisson regression model. The prevalence of current smoking (last 30 days) was 19% (95%CI:16.6-20.6), and harmful alcohol consumption (≥60 g of pure alcohol for men and ≥40 g of pure alcohol for women on an average day) was 2% (95%CI:1.4-2.9). Almost all (99%, 95%CI:98.3-99.3) of the respondents consumed less than five servings of fruits and vegetables combined on an average day and 3% (95%CI:2.7-4.3) had low physical activity. Around 21% (95%CI:19.3-23.7) were overweight or obese (BMI≥25). The prevalence of raised blood pressure (SBP≥140 mm of Hg or DBP≥90 mm of Hg) and raised blood glucose (fasting blood glucose ≥126 mg/dl), including those on medication were 26% (95%CI:23.6-28.0) and 4% (95%CI:2.9-4.5) respectively. Almost one quarter of respondents, 23% (95%CI:20.5-24.9), had raised total cholesterol (total cholesterol ≥190 mg/dl or under current medication for raised cholesterol). he study revealed a lower prevalence of smoking among women than men (APR:0.30; 95%CI:0.25-0.36), and in those who had higher education levels compared to those with no formal education (APR:0.39; 95%CI:0.26-0.58). Harmful alcohol use was also lower in women than men (APR:0.26; 95%CI:0.14-0.48), and in Terai residents compared to hill residents (APR:0.16; 95%CI:0.07-0.36). Physical inactivity was lower among women than men (APR:0.55; 95%CI:0.38-0.80), however women were significantly more overweight and obese (APR:1.19; 95%CI:1.02-1.39). Being overweight or obese was significantly less prevalent in mountain residents than in hill residents (APR:0.41; 95%CI:0.21-0.80), and in rural compared to urban residents (APR:1.39; 95%CI:1.15-1.67). Lower prevalence of raised blood pressure was observed among women than men (APR:0.69; 95%CI: 0.60-0.80). Higher prevalence of raised blood glucose was observed among urban residents compared to rural residents (APR:2.05; 95%CI:1.29-3.25). A higher prevalence of raised total cholesterol was observed among the respondents having higher education levels compared to those respondents having no formal education (APR:1.76; 95%CI:1.35-2.28). CONCLUSION: The prevalence of low fruit and vegetable consumption, overweight and obesity, raised blood pressure and raised total cholesterol is markedly high among the Nepalese population, with variation by demographic and ecological factors and urbanization. Prevention, treatment and control of NCDs and their risk factors in Nepal is an emerging public health problem in the country, and targeted interventions with a multi-sectoral approach need to be urgently implemented.

Smoking prevalence and its impacts on lung cancer mortality in Sub-Saharan Africa: an epidemiological study.

BACKGROUND: Reliable mortality data are sparse for developing countries. Furthermore, risk factor prevalence information is hardly available and thus not taken into consideration when estimating mortality. METHODS: The authors used a validated, statistical model combined with representative smoking prevalence from WHO STEPS surveys to estimate lung cancer mortality for six Sub-Saharan African countries (Benin, Malawi, Mozambique, Niger, Sierra Leone, Swaziland). Results were compared to a reference database (GLOBOCAN). Using different smoking prevalence scenarios, future lung cancer deaths were estimated. RESULTS: The prevalence of current moderate smoking among males ranged from 8.7% to 34.6%. Prevalence was much lower among females. For all countries considered, our mortality estimates were higher than GLOBOCAN estimates that do not consider prevalence: Overall, we estimated 2405 lung cancer deaths for 2008 compared to 531 deaths estimated by GLOBOCAN. Up to 2030, lung cancer deaths are expected to increase in general and by over 100% in Benin and Niger. Even under the assumption of decrease in smoking prevalence, lung cancer mortality will rise. CONCLUSION: On the bases of detailed smoking prevalence information, our findings implicate a higher lung cancer burden in low income countries. The epidemiologic transition in African low-income countries alludes to the need for targeted health prevention efforts.

The global cardiovascular risk transition: associations of four metabolic risk factors with national income, urbanization, and Western diet in 1980 and 2008.

BACKGROUND: It is commonly assumed that cardiovascular disease risk factors are associated with affluence and Westernization. We investigated the associations of body mass index (BMI), fasting plasma glucose, systolic blood pressure, and serum total cholesterol with national income, Western diet, and, for BMI, urbanization in 1980 and 2008. METHODS AND RESULTS: Country-level risk factor estimates for 199 countries between 1980 and 2008 were from a previous systematic analysis of population-based data. We analyzed the associations between risk factors and per capita national income, a measure of Western diet, and, for BMI, the percentage of the population living in urban areas. In 1980, there was a positive association between national income and population mean BMI, systolic blood pressure, and total cholesterol. By 2008, the slope of the association between national income and systolic blood pressure became negative for women and zero for men. Total cholesterol was associated with national income and Western diet in both 1980 and 2008. In 1980, BMI rose with national income and then flattened at ≈Int$7000; by 2008, the relationship resembled an inverted U for women, peaking at middle-income levels. BMI had a positive relationship with the percentage of urban population in both 1980 and 2008. Fasting plasma glucose had weaker associations with these country macro characteristics, but it was positively associated with BMI. CONCLUSIONS: The changing associations of metabolic risk factors with macroeconomic variables indicate that there will be a global pandemic of hyperglycemia and diabetes mellitus, together with high blood pressure in low-income countries, unless effective lifestyle and pharmacological interventions are implemented.

Inequalities in non-communicable diseases and effective responses.

In most countries, people who have a low socioeconomic status and those who live in poor or marginalised communities have a higher risk of dying from non-communicable diseases (NCDs) than do more advantaged groups and communities. Smoking rates, blood pressure, and several other NCD risk factors are often higher in groups with low socioeconomic status than in those with high socioeconomic status; the social gradient also depends on the country's stage of economic development, cultural factors, and social and health policies. Social inequalities in risk factors account for more than half of inequalities in major NCDs, especially for cardiovascular diseases and lung cancer. People in low-income countries and those with low socioeconomic status also have worse access to health care for timely diagnosis and treatment of NCDs than do those in high-income countries or those with higher socioeconomic status. Reduction of NCDs in disadvantaged groups is necessary to achieve substantial decreases in the total NCD burden, making them mutually reinforcing priorities. Effective actions to reduce NCD inequalities include equitable early childhood development programmes and education; removal of barriers to secure employment in disadvantaged groups; comprehensive strategies for tobacco and alcohol control and for dietary salt reduction that target low socioeconomic status groups; universal, financially and physically accessible, high-quality primary care for delivery of preventive interventions and for early detection and treatment of NCDs; and universal insurance and other mechanisms to remove financial barriers to health care.

National, regional, and global trends in adult overweight and obesity prevalences.

BACKGROUND: Overweight and obesity prevalence are commonly used for public and policy communication of the extent of the obesity epidemic, yet comparable estimates of trends in overweight and obesity prevalence by country are not available. METHODS: We estimated trends between 1980 and 2008 in overweight and obesity prevalence and their uncertainty for adults 20 years of age and older in 199 countries and territories. Data were from a previous study, which used a Bayesian hierarchical model to estimate mean body mass index (BMI) based on published and unpublished health examination surveys and epidemiologic studies. Here, we used the estimated mean BMIs in a regression model to predict overweight and obesity prevalence by age, country, year, and sex. The uncertainty of the estimates included both those of the Bayesian hierarchical model and the uncertainty due to cross-walking from mean BMI to overweight and obesity prevalence. RESULTS: The global age-standardized prevalence of obesity nearly doubled from 6.4% (95% uncertainty interval 5.7-7.2%) in 1980 to 12.0% (11.5-12.5%) in 2008. Half of this rise occurred in the 20 years between 1980 and 2000, and half occurred in the 8 years between 2000 and 2008. The age-standardized prevalence of overweight increased from 24.6% (22.7-26.7%) to 34.4% (33.2-35.5%) during the same 28-year period. In 2008, female obesity prevalence ranged from 1.4% (0.7-2.2%) in Bangladesh and 1.5% (0.9-2.4%) in Madagascar to 70.4% (61.9-78.9%) in Tonga and 74.8% (66.7-82.1%) in Nauru. Male obesity was below 1% in Bangladesh, Democratic Republic of the Congo, and Ethiopia, and was highest in Cook Islands (60.1%, 52.6-67.6%) and Nauru (67.9%, 60.5-75.0%). CONCLUSIONS: Globally, the prevalence of overweight and obesity has increased since 1980, and the increase has accelerated. Although obesity increased in most countries, levels and trends varied substantially. These data on trends in overweight and obesity may be used to set targets for obesity prevalence as requested at the United Nations high-level meeting on Prevention and Control of NCDs.

The age associations of blood pressure, cholesterol, and glucose: analysis of health examination surveys from international populations.

BACKGROUND: The age association of cardiovascular disease may be in part because its metabolic risk factors tend to rise with age. Few studies have analyzed age associations of multiple metabolic risks in the same population, especially in nationally representative samples. We examined worldwide variations in the age associations of systolic blood pressure (SBP), total cholesterol (TC), and fasting plasma glucose (FPG). METHODS AND RESULTS: We used individual records from 83 nationally or subnationally representative health examination surveys in 52 countries to fit a linear model to risk factor data between ages 30 and 64 years for SBP and FPG, and between 30 and 54 years for TC. We report the cross-country variation of the slope and intercept of this relationship. We also assessed nonlinear associations in older ages. Between 30 and 64 years of age, SBP increased by 1.7 to 11.6 mm Hg per 10 years of age, and FPG increased by 0.8 to 20.4 mg/dL per 10 years of age in different countries and in the 2 sexes. Between 30 and 54 years of age, TC increased by 0.2 to 22.4 mg/dL per 10 years of age in different surveys and in the 2 sexes. For all risk factors and in most countries, risk factor levels rose more steeply among women than among men, especially for TC. On average, there was a flattening of age-SBP relationship in older ages; TC and FPG age associations reversed in older ages, leading to lower levels in older ages than in middle ages. CONCLUSIONS: The rise with age of major metabolic cardiovascular disease risk factors varied substantially across populations, especially for FPG and TC. TC rose more steeply in high-income countries and FPG in the Oceania countries, the Middle East, and the United States. The SBP age association had no specific income or geographical pattern.

Physical activity in 22 African countries: results from the World Health Organization STEPwise approach to chronic disease risk factor surveillance.

BACKGROUND: Baseline physical activity data are needed to effectively plan programs and policies to prevent noncommunicable diseases, but for many African countries these data are lacking. PURPOSE: To describe and compare levels and patterns of physical activity among adults across 22 African countries. METHODS: Data from 57,038 individuals from 22 countries (11 national and 11 subnational samples) that participated in the STEPwise approach to chronic disease risk factor surveillance (2003-2009) were analyzed in 2010. The validated Global Physical Activity Questionnaire (GPAQ) was used to assess days and duration of physical activity at work, for transport, and during leisure time in a typical week. RESULTS: Overall, 83.8% of men and 75.7% of women met WHO physical activity recommendations (at least 150 minutes of moderate activity per week or equivalent). Country prevalence ranged from 46.8% (Mali) to 96.0% (Mozambique). Physical activity, both at work and for transport, including walking, had large contributions to overall physical activity, while physical activity during leisure time was rare in the analyzed countries. CONCLUSIONS: Physical activity levels varied greatly across African countries and population subgroups. Leisure time activity was consistently low. These data will be useful to inform policymakers and to guide interventions to promote physical activity.

National, regional, and global trends in fasting plasma glucose and diabetes prevalence since 1980: systematic analysis of health examination surveys and epidemiological studies with 370 country-years and 2·7 million participants.

BACKGROUND: Data for trends in glycaemia and diabetes prevalence are needed to understand the effects of diet and lifestyle within populations, assess the performance of interventions, and plan health services. No consistent and comparable global analysis of trends has been done. We estimated trends and their uncertainties in mean fasting plasma glucose (FPG) and diabetes prevalence for adults aged 25 years and older in 199 countries and territories. METHODS: We obtained data from health examination surveys and epidemiological studies (370 country-years and 2·7 million participants). We converted systematically between different glycaemic metrics. For each sex, we used a Bayesian hierarchical model to estimate mean FPG and its uncertainty by age, country, and year, accounting for whether a study was nationally, subnationally, or community representative. FINDINGS: In 2008, global age-standardised mean FPG was 5·50 mmol/L (95% uncertainty interval 5·37-5·63) for men and 5·42 mmol/L (5·29-5·54) for women, having risen by 0·07 mmol/L and 0·09 mmol/L per decade, respectively. Age-standardised adult diabetes prevalence was 9·8% (8·6-11·2) in men and 9·2% (8·0-10·5) in women in 2008, up from 8·3% (6·5-10·4) and 7·5% (5·8-9·6) in 1980. The number of people with diabetes increased from 153 (127-182) million in 1980, to 347 (314-382) million in 2008. We recorded almost no change in mean FPG in east and southeast Asia and central and eastern Europe. Oceania had the largest rise, and the highest mean FPG (6·09 mmol/L, 5·73-6·49 for men; 6·08 mmol/L, 5·72-6·46 for women) and diabetes prevalence (15·5%, 11·6-20·1 for men; and 15·9%, 12·1-20·5 for women) in 2008. Mean FPG and diabetes prevalence in 2008 were also high in south Asia, Latin America and the Caribbean, and central Asia, north Africa, and the Middle East. Mean FPG in 2008 was lowest in sub-Saharan Africa, east and southeast Asia, and high-income Asia-Pacific. In high-income subregions, western Europe had the smallest rise, 0·07 mmol/L per decade for men and 0·03 mmol/L per decade for women; North America had the largest rise, 0·18 mmol/L per decade for men and 0·14 mmol/L per decade for women. INTERPRETATION: Glycaemia and diabetes are rising globally, driven both by population growth and ageing and by increasing age-specific prevalences. Effective preventive interventions are needed, and health systems should prepare to detect and manage diabetes and its sequelae. FUNDING: Bill & Melinda Gates Foundation and WHO.

National, regional, and global trends in systolic blood pressure since 1980: systematic analysis of health examination surveys and epidemiological studies with 786 country-years and 5·4 million participants.

BACKGROUND: Data for trends in blood pressure are needed to understand the effects of its dietary, lifestyle, and pharmacological determinants; set intervention priorities; and evaluate national programmes. However, few worldwide analyses of trends in blood pressure have been done. We estimated worldwide trends in population mean systolic blood pressure (SBP). METHODS: We estimated trends and their uncertainties in mean SBP for adults 25 years and older in 199 countries and territories. We obtained data from published and unpublished health examination surveys and epidemiological studies (786 country-years and 5·4 million participants). For each sex, we used a Bayesian hierarchical model to estimate mean SBP by age, country, and year, accounting for whether a study was nationally representative. FINDINGS: In 2008, age-standardised mean SBP worldwide was 128·1 mm Hg (95% uncertainty interval 126·7-129·4) in men and 124·4 mm Hg (123·0-125·9) in women. Globally, between 1980 and 2008, SBP decreased by 0·8 mm Hg per decade (-0·4 to 2·2, posterior probability of being a true decline=0·90) in men and 1·0 mm Hg per decade (-0·3 to 2·3, posterior probability=0·93) in women. Female SBP decreased by 3·5 mm Hg or more per decade in western Europe and Australasia (posterior probabilities ≥0·999). Male SBP fell most in high-income North America, by 2·8 mm Hg per decade (1·3-4·5, posterior probability >0·999), followed by Australasia and western Europe where it decreased by more than 2·0 mm Hg per decade (posterior probabilities >0·98). SBP rose in Oceania, east Africa, and south and southeast Asia for both sexes, and in west Africa for women, with the increases ranging 0·8-1·6 mm Hg per decade in men (posterior probabilities 0·72-0·91) and 1·0-2·7 mm Hg per decade for women (posterior probabilities 0·75-0·98). Female SBP was highest in some east and west African countries, with means of 135 mm Hg or greater. Male SBP was highest in Baltic and east and west African countries, where mean SBP reached 138 mm Hg or more. Men and women in western Europe had the highest SBP in high-income regions. INTERPRETATION: On average, global population SBP decreased slightly since 1980, but trends varied significantly across regions and countries. SBP is currently highest in low-income and middle-income countries. Effective population-based and personal interventions should be targeted towards low-income and middle-income countries. FUNDING: Funding Bill & Melinda Gates Foundation and WHO.

National, regional, and global trends in body-mass index since 1980: systematic analysis of health examination surveys and epidemiological studies with 960 country-years and 9·1 million participants.

BACKGROUND: Excess bodyweight is a major public health concern. However, few worldwide comparative analyses of long-term trends of body-mass index (BMI) have been done, and none have used recent national health examination surveys. We estimated worldwide trends in population mean BMI. METHODS: We estimated trends and their uncertainties of mean BMI for adults 20 years and older in 199 countries and territories. We obtained data from published and unpublished health examination surveys and epidemiological studies (960 country-years and 9·1 million participants). For each sex, we used a Bayesian hierarchical model to estimate mean BMI by age, country, and year, accounting for whether a study was nationally representative. FINDINGS: Between 1980 and 2008, mean BMI worldwide increased by 0·4 kg/m(2) per decade (95% uncertainty interval 0·2-0·6, posterior probability of being a true increase >0·999) for men and 0·5 kg/m(2) per decade (0·3-0·7, posterior probability >0·999) for women. National BMI change for women ranged from non-significant decreases in 19 countries to increases of more than 2·0 kg/m(2) per decade (posterior probabilities >0·99) in nine countries in Oceania. Male BMI increased in all but eight countries, by more than 2 kg/m(2) per decade in Nauru and Cook Islands (posterior probabilities >0·999). Male and female BMIs in 2008 were highest in some Oceania countries, reaching 33·9 kg/m(2) (32·8-35·0) for men and 35·0 kg/m(2) (33·6-36·3) for women in Nauru. Female BMI was lowest in Bangladesh (20·5 kg/m(2), 19·8-21·3) and male BMI in Democratic Republic of the Congo 19·9 kg/m(2) (18·2-21·5), with BMI less than 21·5 kg/m(2) for both sexes in a few countries in sub-Saharan Africa, and east, south, and southeast Asia. The USA had the highest BMI of high-income countries. In 2008, an estimated 1·46 billion adults (1·41-1·51 billion) worldwide had BMI of 25 kg/m(2) or greater, of these 205 million men (193-217 million) and 297 million women (280-315 million) were obese. INTERPRETATION: Globally, mean BMI has increased since 1980. The trends since 1980, and mean population BMI in 2008, varied substantially between nations. Interventions and policies that can curb or reverse the increase, and mitigate the health effects of high BMI by targeting its metabolic mediators, are needed in most countries. FUNDING: Bill & Melinda Gates Foundation and WHO.

National, regional, and global trends in serum total cholesterol since 1980: systematic analysis of health examination surveys and epidemiological studies with 321 country-years and 3·0 million participants.

BACKGROUND: Data for trends in serum cholesterol are needed to understand the effects of its dietary, lifestyle, and pharmacological determinants; set intervention priorities; and evaluate national programmes. Previous analyses of trends in serum cholesterol were limited to a few countries, with no consistent and comparable global analysis. We estimated worldwide trends in population mean serum total cholesterol. METHODS: We estimated trends and their uncertainties in mean serum total cholesterol for adults 25 years and older in 199 countries and territories. We obtained data from published and unpublished health examination surveys and epidemiological studies (321 country-years and 3·0 million participants). For each sex, we used a Bayesian hierarchical model to estimate mean total cholesterol by age, country, and year, accounting for whether a study was nationally representative. FINDINGS: In 2008, age-standardised mean total cholesterol worldwide was 4·64 mmol/L (95% uncertainty interval 4·51-4·76) for men and 4·76 mmol/L (4·62-4·91) for women. Globally, mean total cholesterol changed little between 1980 and 2008, falling by less than 0·1 mmol/L per decade in men and women. Total cholesterol fell in the high-income region consisting of Australasia, North America, and western Europe, and in central and eastern Europe; the regional declines were about 0·2 mmol/L per decade for both sexes, with posterior probabilities of these being true declines 0·99 or greater. Mean total cholesterol increased in east and southeast Asia and Pacific by 0·08 mmol/L per decade (-0·06 to 0·22, posterior probability=0·86) in men and 0·09 mmol/L per decade (-0·07 to 0·26, posterior probability=0·86) in women. Despite converging trends, serum total cholesterol in 2008 was highest in the high-income region consisting of Australasia, North America, and western Europe; the regional mean was 5·24 mmol/L (5·08-5·39) for men and 5·23 mmol/L (5·03-5·43) for women. It was lowest in sub-Saharan Africa at 4·08 mmol/L (3·82-4·34) for men and 4·27 mmol/L (3·99-4·56) for women. INTERPRETATION: Nutritional policies and pharmacological interventions should be used to accelerate improvements in total cholesterol in regions with decline and to curb or prevent the rise in Asian populations and elsewhere. Population-based surveillance of cholesterol needs to be improved in low-income and middle-income countries. FUNDING: Bill & Melinda Gates Foundation and WHO.

Physical activity and sedentary behavior among schoolchildren: a 34-country comparison.

OBJECTIVE: To describe and compare levels of physical activity and sedentary behavior in schoolchildren from 34 countries across 5 WHO Regions. STUDY DESIGN: The analysis included 72,845 schoolchildren from 34 countries that participated in the Global School-based Student Health Survey (GSHS) and conducted data collection between 2003 and 2007. The questionnaire included questions on overall physical activity, walking, or biking to school, and on time spent sitting. RESULTS: Very few students engaged in sufficient physical activity. Across all countries, 23.8% of boys and 15.4% of girls met recommendations, with the lowest prevalence in Philippines and Zambia (both 8.8%) and the highest in India (37.5%). The prevalence of walking or riding a bicycle to school ranged from 18.6% in United Arab Emirates to 84.8% in China. In more than half of the countries, more than one third of the students spent 3 or more hours per day on sedentary activities, excluding the hours spent sitting at school and doing homework. CONCLUSIONS: The great majority of students did not meet physical activity recommendations. Additionally, levels of sedentariness were high. These findings require immediate action, and efforts should be made worldwide to increase levels of physical activity among schoolchildren.