Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities^1,2. This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity^3–6. Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017—and more than 80% in some low- and middle-income regions—was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing—and in some countries reversal—of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.

High blood cholesterol is typically considered a feature of wealthy western countries ^1,2 . However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world ³ 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 health ^4,5 . 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.

Lithium remains first choice as maintenance treatment for bipolar affective disorder. Yet, about half of all individuals may stop their treatment at some point, despite lithium’s proven benefits concerning the prevention of severe affective episodes and suicide. Retrospective cohort study in the Swedish region of Norrbotten into the causes of lithium discontinuation. The study was set up to (1) test whether patients with bipolar affective disorder or schizoaffective disorder, treated with lithium maintenance therapy, were more likely to discontinue lithium because of adverse effects than lack of therapeutic effectiveness, (2) explore gender differences, (3) understand the role of diagnosis and (4) identify who, patient or doctor, took the initiative to stop lithium. Review of medical records for all episodes of lithium discontinuation that had occurred between 1997 and 2013 with the intent to stop lithium for good. Of 873 patients treated with lithium, 54% discontinued lithium, corresponding to 561 episodes of lithium discontinuation. In 62% of episodes, lithium was discontinued due to adverse effects, in 44% due to psychiatric reasons, and in 12% due to physical reasons interfering with lithium treatment. The five single most common adverse effects leading to lithium discontinuation were diarrhoea (13%), tremor (11%), polyuria/polydipsia/diabetes insipidus (9%), creatinine increase (9%) and weight gain (7%). Women were as likely as men to take the initiative to stop lithium, but twice as likely to consult a doctor before taking action (p < 0.01). Patients with type 1 BPAD or SZD were more likely to discontinue lithium than patients with type 2 or unspecified BPAD (p < 0.01). Patients with type 1 BPAD or SZD were more likely to refuse medication (p < 0.01). Conversely, patients with type 2 or unspecified BPAD were three times as likely to discontinue lithium for lack or perceived lack of effectiveness (p < 0.001). Stopping lithium treatment is common and occurs mostly due to adverse effects. It is important to discuss potential adverse effects with patients before initiation and continuously during lithium treatment, to reduce the frequency of potentially unnecessary discontinuations.

Rural communities have a higher burden of cardiovascular risk factors than urban communities. In Sweden, socioeconomic transition and urbanization have led to decreased populations in rural areas and changing characteristics of the remaining inhabitants. We investigated the risk factors in urban and rural populations in Northern Sweden. The 2009 Northern Sweden MONICA Study invited a random sample of 2,500 people, 25 to 74 years and 69.2% participated. Community size was classified as rural = 15,000. We adjusted our analysis for age, gender and education. The rural population was older and the proportion of men was higher than in the urban areas. Having only primary education was more common in rural areas than in urban areas (26.2% vs. 12.3%). Waist and hip circumference, body mass index (BMI), and total cholesterol levels were higher in rural areas than in urban areas, even after adjusting for differences in age and gender. The largest differences between rural and urban dwellers were seen in waist circumference of women (4.8 cm), BMI of women (1.8 units) and cholesterol of men (0.37 mmol/l). Blood pressure was higher in rural areas, but not after adjusting for age and gender. Participants in rural areas were more often treated for hypertension and hyperlipidaemia, hospitalized for myocardial infarction and diagnosed with diabetes. However, after adjusting for age and gender, there were no differences. The odds ratio for being physically active comparing rural areas to urban areas was 0.73 (95% CI 0.53; 1.01). Smoking, snuff use and the prevalence of pathological glucose tolerance did not differ between community sizes. Middle-sized communities often had values in between those found in rural and urban communities, but overall they were more similar to the rural population. Further adjustment for education did not change the results for any variable. In 2009 the rural population in northern Sweden was older, with less education, higher BMI, more sedentary lifestyle, and had higher cholesterol levels than the urban population. The rural population should be considered targets for focused preventive interventions, but with due consideration of the socioeconomic and cultural context.

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.

Background: The association between lithium and thyroid dysfunction has long been known. However, it remains unknown if lithium-associated hypothyroidism is reversible once lithium treatment has been stopped. Aims: To determine whether lithium-associated hypothyroidism was reversible in patients who subsequently discontinued lithium. Methods: A retrospective cohort study in the Swedish region of Norrbotten into the effects and side- effects of lithium treatment and other drugs for relapse prevention (Lithium – Study into Effects and Side Effects). For this particular study, we reviewed medical records between 1997 and 2015 of patients with lithium-associated hypothyroidism who had discontinued lithium. Results: Of 1340 patients screened, 90 were included. Of these, 27% had overt hypothyroidism at the start of thyroid replacement therapy. The mean delay from starting lithium to starting thyroid replacement therapy was 2.3 years (SD 4.7). In total, 50% of patients received thyroid replacement therapy within 10 months of starting lithium. Of 85 patients available for follow-up, 41% stopped thyroid replacement therapy after lithium discontinuation. Only six patients reinstated thyroid replacement therapy subsequently. Of these, only one had overt hypothyroidism. Conclusions: Lithium-associated hypothyroidism seems reversible in most patients once lithium has been discontinued. In such cases, thyroid replacement therapy discontinuation could be attempted much more often than currently done. Based on the limited evidence of our study, we can expect hypothyroidism to recur early after thyroid replacement therapy discontinuation, if at all.