Ecological study of breast cancer incidence among nationals and non-nationals in the Gulf Cooperation Council countries

Background: Breast cancer incidence is increasing in the Gulf Cooperation Council (GCC) countries: Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and United Arab Emirates. Aims: This study analysed geographical patterns, time trends, and age distribution of female breast cancer incidence among nationals and non-nationals in GCC countries. Methods: Available cancer registry data for 1979-2016 were retrieved for the GCC countries. Age-standardized rates (ASRs) per 100 000 women were calculated using the World standard population. Comparisons were made by calculating comparative incidence figures. Results: From 1998 to 2012, incidence among nationals was highest in Bahrain (ASR 61.85), Kuwait (ASR 52.66), and Qatar (ASR 56.90) and lowest in Saudi Arabia (ASR 19.76), Oman (ASR 22.33), and United Arab Emirates (ASR 31.05). In the most recent period, data were available only in Qatar (2014-2016) and Saudi Arabia (2013-2015). Non-nationals and nationals in Qatar had higher incidence rates than in Saudi Arabia. Incidence among nationals in Qatar was at least twice that in Saudi Arabia (comparative incidence figure 2.32). Incidence among non-nationals in Qatar was 3 times higher than in Saudi Arabia. Among nationals in Kuwait, 10.8% of cases of breast cancer occurred in women aged < 40 years in 2008-2012, compared with 24.2% in non-nationals in Qatar in 2014-2016. Conclusion: Breast cancer incidence has increased over time among women in most GCC countries, likely reflecting the improvements in healthcare access and screening programmes. Nationals and non-nationals developed breast cancer at a younger age than women in other high-income countries. Increased screening uptake is still required in the region. Evidence-based, locally-informed interventions should be implemented to address risk factors specific to the nationals and non-nationals in the GCC countries.