Increased dementia risk for those who are overweight or obese

Yuxian Ma, Olesya Ajnakina, Andrew Steptoe and Dorina Cadar

Dementia is a major health challenge that could steal away the opportunity for successful ageing of the population. A priority is to identify lifestyle factors that may reduce the risk of dementia, or even prevent it. The modifiable risk factors for vascular diseases — such as smoking, excessive alcohol intake, lack of physical activity, low intake of antioxidants and high intake of saturated fats — are receiving greater attention in this area because of their association with cognitive impairment and dementia in older people.

Obesity, which is linked to lifestyle behaviours, is an important modifiable risk factor. In our recent study carried out at the UCL Department of Behavioural Science and Health, we found that being overweight or obese was associated with a greater risk of developing dementia.

Continue reading “Increased dementia risk for those who are overweight or obese”

Screening participation and general health: another cautionary tale

Mette Lise Lousdal and Henrik Støvring

While organised mammography screening programs were being gradually introduced across various countries, researchers could study the impact of screening on breast cancer mortality by comparing mortality in areas with and without screening. Now that screening has been fully implemented in most Western countries, researchers can only compare women who participate in screening with those who do not participate.

Women who do not participate in screening may seem to be a good choice as a comparison group, as they are not affected by screening. But the question is: can non-participants reflect how breast cancer mortality would have developed in women in general without the introduction of screening?

Continue reading “Screening participation and general health: another cautionary tale”

Herd immunity and the coronavirus

Stephen Leeder

The first preliminary (Phase 1) trial in humans of a coronavirus vaccine in the US is a good moment for reflection on the immunology of this illness.

We need to be cautious. It is not the virus that leads to interstitial lung disease and death. It is our immunological response, the “cytokine storm”, that causes severe illness.

This is comparable to the devastation of the respiratory syncytial virus, persistently responsible for bronchiolitis in the very young, killing tens of thousands worldwide each year.

If the vaccine is both effective and safe, enough people will be immune, and transmission from them to the rest of us will be much diminished. Indeed, if enough people are immune — generally about 60% (“herd immunity”) — either through exposure or vaccination, transmission ceases.

Continue reading “Herd immunity and the coronavirus”

IEA Statement on the Novel Coronavirus (COVID-19) Pandemic

The Council of the International Epidemiological Association, its affiliate bodies and members have viewed with concern the rapidly evolving situation with the novel Coronavirus (COVID-19) pandemic. Since the onset of the outbreak in December 2019, this disease has affected 162 countries and territories (as of 17/03/2020) with over 184,000 people affected and 7,000 deaths. With countries at various response stages of anticipation, early detection, containment, and mitigation, we commend the efforts of the WHO, various national governments, non-governmental organizations, health workers and advocates in addressing this health crisis.

Continue reading “IEA Statement on the Novel Coronavirus (COVID-19) Pandemic”

Coronavirus in Australia

Tony Blakely

If COVID-19 were allowed to spread unchecked, it would devastate Australian society. My modelling suggests that Australia could get as many as 400,000 to 600,000 infections a day at the peak – translating to about 150,000 to 200,000 symptomatic cases a day. There’s no way we can let the numbers get that high. It would be absolute carnage.

Continue reading “Coronavirus in Australia”

Did you know that breathing in smoke from solid fuels or tobacco may increase your risk of dying from chronic liver disease?

Ka Hung Chan, Derrick Bennett, Kin Bong Hubert Lam and Zhengming Chen

Chronic liver diseases (CLD), such as liver cirrhosis and liver cancer, affect more than 800 million people worldwide, with a third of these living in China. Smoke from solid fuels (e.g. coal and wood) and tobacco contains high concentrations of thousands of toxic chemicals. When breathed in, these chemicals can reach and harm major internal organs, including the liver.

Continue reading “Did you know that breathing in smoke from solid fuels or tobacco may increase your risk of dying from chronic liver disease?”

Salami publishing: why we need to talk about it

Ding (Melody) Ding, Adrian Bauman, Esther van Sluijs and Klaus Gebel

Have you ever had this experience? You’re looking into the literature on the association between an exposure (such as accelerometer-measured physical activity) and an outcome (such as all-cause mortality) and, you find six papers, not one, written by the same authors based on the same sample. “Are these the same paper?”, you wonder. On careful perusal of the titles and abstracts, you realise that these are different papers on similar and related research questions, only with minor differences: one looks at the association in men, another in women, a third one in older adults, a fourth in a subsample with a pre-existing condition …

Continue reading “Salami publishing: why we need to talk about it”

With great (statistical) power comes great responsibility

Tessa Strain and Søren Brage

We are all familiar with studies that investigate the associations between physical activity and outcomes such as death or cardiovascular disease. However, we rarely focus on the length of time over which these study participants are followed up to see if one of the outcomes occurs.

Continue reading “With great (statistical) power comes great responsibility”

Childhood diarrhoeal illness may be underestimated in national health surveys

Katie Overbey, Kellogg Schwab and Natalie Exum

For children in low-income countries, diarrhoea remains a major cause of death and can lead to long-term health consequences. Accurate estimates of childhood diarrhoeal illness are crucial to evaluating the success of campaigns to defeat diarrhoea and improve health in countries where the burden of diarrhoea is high.

In our study, recently published in the IJE, we found that caregivers may underestimate diarrhoeal diseases in children aged under 5 years when asked to recall whether the children had diarrhoea in the previous 2 weeks. Compared with a 1-week recall period, there was a consistent underestimation of the prevalence of diarrhoea across five countries in sub-Saharan Africa.

Continue reading “Childhood diarrhoeal illness may be underestimated in national health surveys”

Take my breath away: India’s crop residue burning affects respiratory health

Suman Chakrabarti, Md Tajuddin Khan and Samuel Scott

Respiratory infections are the most common chronic disease in children globally and a leading cause of death in developing countries. This situation is exacerbated by air pollution.

Air pollution in northern India, mainly New Delhi and the neighbouring states, is exacting a toll on the health of residents, making global headlines and highlighting the severity and extent of this public health disaster in one of the world’s fastest-growing economies.

A contributory factor to air pollution in northern India is the harmful practice of crop residue burning — when farmers burn the crop residue to clear fields before sowing a new crop. Although banned by the Indian government in 2015, this practice remains prevalent in many parts of the northern Indian states of Punjab, Haryana and Uttar Pradesh.

Continue reading “Take my breath away: India’s crop residue burning affects respiratory health”