Social inequality in Germany has a significant impact on the rate of new cancer cases - and this trend is increasing. This is what a German research team reports after analyzing data from eight federal states. Accordingly, the age-standardized rate of new cancers has been declining for years. However, this trend is much clearer in socially better off regions than elsewhere, writes the team led by Lina Jansen from the German Cancer Research Center (DKFZ) in the "International Journal of Cancer". If data are age-standardized, it means that a calculation method was used in which the incidence or mortality rates are converted to a (fictitious) reference population with a defined age structure.
Studies from Germany and other countries show that social inequality can influence the rate of cancer. In Germany, between 2010 and 2013, 7.3 percent more men in the socio-economically weakest regions were diagnosed with cancer than in the wealthiest areas.
However, since 2007, the age-standardized incidence rate for almost all types of cancer has been falling in Germany – with the exception of lung cancer in women. According to the researchers, however, little research has been carried out into how social inequalities affect this trend. Now the team examined the development of cancer diagnoses for eight German federal states with a total of around 49 million inhabitants - 60 percent of the total German population - for the period from 2007 to 2018 Hesse, Baden-Württemberg, Berlin and the five East German federal states were not taken into account due to poor data availability.
The study compared the cancer diagnoses at county and district level with the respective socio-economic index. It was divided into five groups, depending on factors such as income, employment rate, education, environment and safety. For all groups, the incidence rate fell from 2007 to 2018 for almost all types of cancer. However, for all cancers, as well as for colorectal cancer and lung cancer, the declines in men in the most disadvantaged regions were significantly weaker than those in the more affluent areas.
And this inequality increased over the observation period: while men in the most socio-economically disadvantaged regions had a 7 percent higher cancer incidence rate in 2007 than in the least disadvantaged regions, this difference rose to 23 percent in 2018. For women it increased he was a little less strong – also from seven to 20 percent.
This discrepancy was particularly pronounced in lung cancer: In 2018, it occurred 82 percent more frequently in men and even 88 percent more frequently in women in the socio-economically weakest regions compared to the most affluent areas. Further analyzes provide indications of the causes of this trend: health care - such as doctor density, distance to the nearest medical center, number of hospital beds or nursing homes - is not very strong between the socio-economically different regions. "So the social factors seem to play a much bigger role than the general infrastructure," concludes Jansen.
On the other hand, there is a clear socio-economic gap in the prevalence of tobacco and alcohol consumption, lack of exercise or severe obesity - all factors that can increase the risk of cancer. "Our results show once again that we must make special efforts in the future to ensure that all people benefit equally from recommendations for a healthy lifestyle and from cancer screening tests - regardless of their postcode," emphasizes Jansen.