Rahimzadeh Shadi, Bentham James, Burczynska Beata, Farzadfar Farshad, Di Cesare Mariachiara
Institute of Public Health and Wellbeing, University of Essex, Colchester, United Kingdom.
School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne, United Kingdom.
PLoS One. 2025 Sep 11;20(9):e0330017. doi: 10.1371/journal.pone.0330017. eCollection 2025.
While trends in breast cancer incidence in Iran are generally monitored at the national level, little is known about subnational variations in these trends. This study aimed to assess the levels and trends (2000-2021) of the relative risk (RR) of breast cancer incidence at the district level in Iran and its relation to key socioeconomic dimensions to understand the full extent of geographical and social inequalities in the country associated with breast cancer morbidity.
District-level incidence data by age and sex from the National Cancer Registry System of the Iranian Ministry of Health were used. Related covariates were extracted from the Census and Household Expenditure and Income Survey (HEIS) datasets. The RR of breast cancer incidence was estimated in women above the age of 30 for all 316 districts in Iran from 2000 to 2010 using a Bayesian spatiotemporal model. Finally, predictions were estimated for the period 2011-2021.
The national RR of breast cancer incidence in Iran increased from 0.21 (95% credible interval (CrI): 0.19, 0.22) in 2000 to 0.66 (0.63, 0.68) in 2010 and 1.23 (1.18, 1.28) in 2021. The RR of breast cancer incidence was highest in Yazd (1.96 [1.63, 2.33]), Shiraz (1.90 [1.72, 2.09]) and Shemiranat (1.90 [1.12, 2.91]) in 2010 and in Tehran (3.99 [3.86, 4.33]), Bushehr (3.89 [3.07, 4.77]) and Abadan (3.67 [2.99, 4.39]) in 2021. In contrast, Savojbolagh, Saravan and Nikshahr had the lowest RRs in both 2010 (0.11 [0.05, 0.20], 0.17 [0.08, 0.30] and 0.20 [0.09, 0.36], respectively) and 2021 (0.19 [0.10, 0.33], 0.34 [0.18, 0.54] and 0.35 [0.17, 0.62], respectively). The RR of breast cancer incidence was 60% greater across districts in the highest YOS quintile (average years of schooling: 3.9) than in those in the lowest YOS quintile (average years of schooling: 2.2; relative index of inequality: 1.6).
The results show that the RR of breast cancer incidence has increased over time (2000-2021) at the national and subnational levels in Iran. Breast cancer is one of the few diseases with a positive education gradient, with a greater RR of breast cancer incidence among higher-educated women than among lower-educated women. However, this is likely due to better awareness of diagnostic approaches and access to those approaches rather than reflecting patterns in the true incidence of breast cancer. While social inequalities are a major barrier to reducing the prevalence and incidence of breast cancer, it is important to track the progress made at the district level based on the characteristics of specific policies aimed at reducing health inequalities. A scaling-up in the quality of healthcare services, national and subnational policies addressing prevention and treatment, and more specialised training programmes for women's health are needed.
虽然伊朗乳腺癌发病率的趋势通常在国家层面进行监测，但对于这些趋势在国家以下层面的差异了解甚少。本研究旨在评估伊朗地区层面乳腺癌发病率相对风险（RR）的水平和趋势（2000 - 2021年）及其与关键社会经济维度的关系，以了解该国与乳腺癌发病相关的地理和社会不平等的全貌。
使用了伊朗卫生部国家癌症登记系统按年龄和性别的地区层面发病数据。相关协变量从人口普查以及家庭支出和收入调查（HEIS）数据集中提取。利用贝叶斯时空模型估计了2000年至2010年伊朗所有316个地区30岁以上女性乳腺癌发病率的RR。最后，对2011 - 2021年期间进行了预测。
伊朗全国乳腺癌发病率的RR从2000年的0.21（95%可信区间（CrI）：0.19，0.22）增加到2010年的0.66（0.63，0.68）和2021年的1.23（1.18，1.28）。2010年乳腺癌发病率RR最高的地区是亚兹德（1.96 [1.63，2.33]）、设拉子（1.90 [1.72，2.09]）和谢米兰特（1.90 [1.12，2.91]），2021年是德黑兰（3.99 [3.86，4.33]）、布什尔（3.89 [3.07，4.77]）和阿巴丹（3.67 [2.99，4.39]）。相比之下，萨沃乔拉格、萨拉万和尼克沙赫尔在2010年（分别为0.11 [0.05，0.20]、0.17 [0.08，0.30]和0.20 [0.09，0.36]）和2021年（分别为0.19 [0.10，0.33]、0.34 [
