Regular exercise, even in polluted areas, can lower risk of cancer mortality

Yacong Bo and Xiang Qian Lao

Regular exercise is recognised as providing significant lifestyle-related protection against non-communicable diseases. It can also reduce the likelihood of cardiovascular disease, cancer and premature death. By contrast, long-term exposure to fine particulate matter (PM2.5) can increase the likelihood of respiratory and cardiovascular disease and certain cancers, leading to premature death.

Outdoor exercise might increase the inhalation and deposition of air pollutants, potentially counteracting its beneficial effects. Evaluation of this risk–benefit relationship has become an important public health concern because more than 91% of the global population lives in areas where air quality fails to meet the 2005 World Health Organization guidelines.

Continue reading “Regular exercise, even in polluted areas, can lower risk of cancer mortality”

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”

Is it time to establish breast cancer as a smoking-related cancer?

Inger T Gram

Smoking was established as a cause of lung cancer in the late 1950s. It then took another 50 years to establish that colorectal cancer was also a smoking-related cancer. However, as of 2018, a causal relationship between smoking and breast cancer had not yet been established. It may seem strange that it is taking so long to prove that smoking is a cause of all three of the most common cancers globally. Breast and lung cancer each account for 2.09 million cases annually and colorectal cancer for 1.8 million.

Continue reading “Is it time to establish breast cancer as a smoking-related cancer?”

Circulating cotinine concentrations and lung cancer risk evaluated in 20 international cohorts

Tricia L Larose, Arnulf Langhammer and Mattias Johansson, for the Lung Cancer Cohort Consortium (LC3)

Lung cancer is one of the most common cancers worldwide, accounting for 2.09 million cases and 1.76 million deaths in 2018. Two of the most prolific cancer epidemiologists of our time — Sir Richard Doll and Sir Bradford Hill — identified smoking as the biggest cause of lung cancer in their seminal report, “Smoking and Carcinoma of the Lung”, published in the British Medical Journal in 1950. Nearly 70 years later, smoking remains the predominant risk factor for lung cancer, as well as for 15 additional cancers and other non-communicable diseases.

Continue reading “Circulating cotinine concentrations and lung cancer risk evaluated in 20 international cohorts”

Families (and their histories) will always be vital for cancer risk assessment

Mary Beth TerryMary Beth Terry

My husband’s dad died of cancer. So did most of his uncles. On both sides. Should he be concerned? Of course. Family history is one of the strongest predictors of most cancers. Few risk factors increase cancer risk more than family history, with the exception of certain viruses and smoking. The increase in risk from family history is even greater if there are multiple individuals within a family with the same cancer and/or if the family members are diagnosed at an early age. The clustering of cancers within families has led to the identification of many causal cancer genes. Genetic testing for these known cancer genes has become the standard of cancer risk assessment for many individuals with a family history. Continue reading “Families (and their histories) will always be vital for cancer risk assessment”

Waterpipe smoking might be just as harmful as smoking cigarettes

Reem Waziry and Elie Akl

Elie_Akl[1] Reem Waziry headshotWaterpipe, also known as shisha, goza, narghile, arghile and hookah, is a traditional method for smoking tobacco. While it originated in Turkey, India and Iran, its use has spread on a global level over the past decade to the point of being labelled a global epidemic.

There are a number of explanations for the global spread of waterpipe tobacco smoking. First, people use it as a way to socialize, as it is smoked in groups. Second, the production of sweetened and flavoured tobacco (Maassel), resulting in aromatic and smooth smoke, can make it more appealing than cigarette smoking. Another major reason is a common misconception that waterpipe tobacco smoking is not harmful, or is less harmful than smoking cigarettes. Continue reading “Waterpipe smoking might be just as harmful as smoking cigarettes”

Parkinson’s disease and cancer risk: is there a relationship?

Freedman_Michal_2015_ORIG_160x140WEBD. Michal Freedman

Some previous epidemiologic studies have suggested that having Parkinson’s disease decreases your risk of developing cancer, and vice versa. If true, this finding could provide insight into underlying biologic mechanisms for the two diseases.

How we set out to answer the question
In a study published in the International Journal of Epidemiology we used data from Medicare, a U.S. federal health insurance programme for those aged ≥65 years, linked to U.S. cancer registry data to examine the relationship between Parkinson’s disease and cancer. Because we used Medicare data, we were limited to people aged 65 years and older. However, as the Medicare database is very large, we were able to examine relationships in whites and non-whites, in men and women, and in different age groups (all above 65 years).

We hypothesized that previous studies may have found a lower risk of cancer after Parkinson’s disease because cancer screening or medical work-ups were less frequent in people with a debilitating condition such as Parkinson’s than in people without such a condition. Continue reading “Parkinson’s disease and cancer risk: is there a relationship?”

World Cancer Day 2016

WCD with logoWorld Cancer Day is a global event which takes place annually on 4 February to educate and raise awareness about the disease with the aim of saving millions of preventable deaths each year. This year’s theme ‘We can. I can’ explores how everyone can do their part to reduce the global burden of cancer.

To mark World Cancer Day, the International Journal of Epidemiology has published a free article collection (available until 4 May 2016) showcasing the latest epidemiological research into a variety of risk factors for cancer: Continue reading “World Cancer Day 2016”

Fluoridation of drinking water supplies: tapping into the debate

This article originally appeared on the OUPblog on 6 March 2014: http://blog.oup.com/2014/03/fluoridation-drinking-water-supplies/

Karen Blakey and Richard J.Q. McNally

Since their introduction in the United States in the 1940s, artificial fluoridation programmes have been credited with reducing tooth decay, particularly in deprived areas. They are acknowledged by the US Centers for Disease Control and Prevention as one of the ten great public health achievements of the 20th century (alongside vaccination and the recognition of tobacco use as a health hazard). Such plaudits however, have only gone on to fuel what is an extremely polarised ‘water fight’. Those opposed to artificial fluoridation continue to claim it causes a range of health conditions and diseases such as reduced IQ in children, reduced thyroid function, and increased risk of bone cancer. Regardless of the controversy, the one thing that everyone agrees upon is that little or no high quality research is available to confirm or refute any public concerns. Continue reading “Fluoridation of drinking water supplies: tapping into the debate”