During the past twelve months, much of NDPH’s work refocussed naturally on addressing the COVID-19 pandemic, including testing candidate treatments for hospitalised patients, assisting nationwide infection surveys and developing an ethical framework for contact tracing. Nevertheless, the department continued to produce high-quality research outputs across all areas of health. Here, we review some of the most impactful non-COVID-19 studies of 2020 and ask the lead researchers what’s next for their work.
Established: a definite link between obesity and kidney disease
A study led by NDPH’s Medical Research Council Population Health Research Unit that used almost 300,000 DNA samples from UK Biobank found that obesity is a direct cause of kidney disease. Furthermore, for most cases of obesity-associated kidney disease, diabetes and blood pressure were the driving causes. Clinician scientist Dr William Herrington commented ‘This has refocused our clinical research attention on testing whether interventions which can modify all three (i.e. reduce weight, blood pressure and diabetes risk) can slow the progression of kidney disease. In 2021 we will complete recruitment of 6000 people into a trial called EMPA-KIDNEY which is testing empagliflozin versus placebo (a dummy pill) in kidney disease patients with and without diabetes. The drug causes both blood sugar (about 10 teaspoons a day) and some salt to pass into the urine.’ Results are expected in 2022.
Childhood smoking has significant impacts on premature death
In a study on 150,000 adults in Cuba, NDPH researchers from the Clinical Trial Service & Epidemiological Studies Unit (CTSU) found that starting to smoke in childhood approximately doubled the risk of premature death as an adult. Furthermore, starting in early childhood (before age 10) was associated with nearly three times the excess risk as starting at age 15 or older. However, those who quit smoking before the age of 40 avoided more than 90% of the excess risk associated with prolonged smoking. Epidemiologist and statistician Professor Sarah Lewington said ‘CTSU is currently collaborating with local principal investigators in China, Mexico, Russia, Cuba and India, to study the emerging epidemic of tobacco-related mortality in low- and middle-income countries. Data from these and previous CTSU studies contribute to the World Health Organization’s Framework Convention on Tobacco Control guidelines, which provide a foundation for countries to implement controls on tobacco.’
Research and theatre combined to reduce stigma against maternal mental illness
In March 2020, after birth, a play developed in partnership with researchers from NDPH’s National Perinatal Epidemiology Unit and written by Oxford playwright Zena Forster, won funding to be developed as a two-week residency. Based on the testimonies of women who experienced psychosis after the birth of their babies, the story uses humour to offer a life-affirming portrait of women’s resilience and survival. Professor Rachel Rowe from NPEU said ‘We hope to engage audiences with research evidence about maternal mental health, to raise awareness, reduce stigma, encourage discussion and ultimately improve care for women affected by postnatal mental illness.’ Producer Emma Dolman described the plans for after birth: ‘We are aiming for live performances in June 2021 at North Wall Arts Centre Oxford, besides a national theatre tour from Autumn 2021. We are also putting in bids to fund making a film of the live performance to reach broader and wider audiences.’
Soft drinks industry responds to calls for reduced sugar contents
According to research by the Diet, Data and Interventions Group at NDPH, there was a 29% reduction in the total amount of sugar sold in soft drinks in the UK between 2015 and 2018, despite volumes of soft drinks sales increasing by 7%. This indicates that sustained pressure on the soft drink industry (including the introduction of the UK Soft Drink Industry Level, SDIL) to lower sugar contents is working. Lead researcher Dr Lauren Bandy said ‘I hope this study continues to contribute to the evidence supporting the UK SDIL besides the wider debate around the effectiveness of voluntary reformulation targets compared to mandatory policies. This paper has led to further work investigating how the sugar contents of foods that contribute the most to children’s sugar intakes (like confectionery, biscuits, breakfast cereals and yoghurts) have changed over time, which we aim to publish in the New Year.’
The costs of self-harm are considerably higher than previously thought
In the first detailed study of self-harm and associated hospital costs, researchers from Oxford University’s Centre for Suicide Research and NDPH’s Health Economics Research Centre found that self-harm cost hospitals in England an estimated £128.6m in 2013. Furthermore, the number of people visiting hospital for self-harm injuries was 60% higher than previously estimated by Public Health England. The incidence of self-harm was lower in coastal areas, higher inland, and highest in London. Lead author, Dr Apostolos Tsiachristas, said ‘These results may assist national and local health decision makers in planning the distribution of funds for self-harm and prioritising interventions in areas with the highest need for tackling self-harm. By providing the incidence of self-harm for different regions by gender and age, this study highlights sub-populations where additional resources might potentially be targeted.’
Widespread dietary reform needed to meet global environmental and health targets
A study on 85 countries led by NDPH found that most dietary recommendations provided by national governments and the World Health Organization are not compatible with global environmental and health targets, including the Paris Climate Agreement and the Sustainable Development Goals. Meeting these targets will require much stricter limits on meat and dairy, and greater consumption of whole grains, fruits and vegetables, legumes, and nuts. Dr Marco Springmann, who led the study, said ‘We hope these results will stimulate reform of national and international dietary guidelines in line with current scientific understanding of healthy and sustainable diets, particularly the need to reduce over-consumption of animal-source foods in most countries.’ Professor Mike Rayner said ‘There also needs to be greater investment in measures to facilitate healthier and sustainable diets, such as aligning school and work-place canteen menus with the guidelines and introducing new taxes and subsidies to incentivise sustainable dietary patterns.’