Increasing Incidence of Brain and Nervous Tumours in Urban Shanghai, China, 1983-2007

Background: Wide use of cellular telephones has given rise to concerns about adverse health effects, especially in the brain, which might caused by the low power microwave-frequency signal transmitted by the antennas on handsets. Subscribers to cellular telephone services increased from mid-1990s in Shanghai; time trends in brain and nervous tumour after 2000 may supply information about possible associations between tumour risk and cellular telephones use.
Methods: We investigated time trends in the incidence of brain and nervous tumour in urban Shanghai, from 1983 to 2007, applying joinpoint regression models to analyze the annual incidence rates and to predict future trends.
Results: from 1983 to 2007, the age-adjusted incidence rate of brain and nervous tumours increased gradually by 1.2% per year (95% confidence interval [CI] = 0.4% to 1.9%) among men and 2.8% per year (95% CI =2.1 to 3.4) among women. Age-adjusted incidences of brain and nervous tumours in urban Shanghai for 2020 were estimated to 7.4 and 10.9 per 100,000 person-years.
Conclusion: The study did not support an association between cellular telephone use and increased risk of brain and nervous tumours. However, considering of the increasing incidence rate of brain and nervous tumours now and in the future, in addition to the high prevalence of mobile phone exposure in the population and worldwide, assessment of longer follow-up time trends in brain tumour incidence rates is warranted.