Objective: There is a lack of studies evaluating the COVID-19 pandemic effect on breast cancer detection according to age group. This study aimed to assess the pandemic impact on the trend of mammograms, breast biopsies, and breast cancer stage at diagnosis according to age group. Methods: This was an ecological time series study by inflection point regression model. We used data from women aged between 30 and 49, 50 and 69, and 70 years or more available in an open-access dataset of the Brazilian public healthcare system (2017-2021). We analyzed the trend of the variables in the pre-pandemic and the pandemic effect on the total time series. Results: The decreasing or stationary trend of mammograms in the pre-pandemic has changed to a decreasing trend in the total time series in all age groups. Before the pandemic, the increasing trend of breast biopsies has changed to stationary in the total time series in all age groups. The increasing trend of tumors at stages O to II in the pre-pandemic has changed to decreasing or stationary in the total time series. Finally, the increasing trend of tumors at stage III or IV remained increasing in the total time series in all age groups. Conclusion: The pandemic has changed the stationary or increasing trend to a decreasing or stationary trend of mammograms, breast biopsies, and tumors at stages 0 to II but has not influenced the increasing trend of tumors at stages III and IV in all age groups.


中文翻译：

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新冠病毒大流行与分年龄段乳腺癌确诊趋势：总时间序列和间断时间序列研究

目的：缺乏根据年龄组评估 COVID-19 大流行对乳腺癌检测的影响的研究。本研究旨在根据年龄组评估大流行对乳房 X 线照片、乳房活检和乳腺癌诊断分期趋势的影响。方法：这是通过拐点回归模型进行的生态时间序列研究。我们使用了来自 30 至 49 岁、50 至 69 岁以及 70 岁或以上女性的数据，这些数据可在巴西公共医疗保健系统（2017-2021 年）的开放获取数据集中获得。我们分析了大流行前变量的趋势和大流行对总时间序列的影响。结果：在所有年龄组的总时间序列中，大流行前乳房 X 线照片的下降或稳定趋势已变为下降趋势。疫情前，在所有年龄组的总时间序列中，乳房活检的增加趋势已变为平稳。大流行前O至II期肿瘤的增加趋势在总时间序列中已变为减少或稳定。最后，在所有年龄组的总时间序列中，III 期或 IV 期肿瘤的增加趋势仍在增加。结论：大流行改变了乳腺 X 线照片、乳腺活检和 0 到 II 期肿瘤的平稳或上升趋势，但并未影响所有年龄组的 III 期和 IV 期肿瘤的上升趋势。III期或IV期肿瘤的增加趋势在所有年龄组的总时间序列中保持增加。结论：大流行改变了乳腺 X 线照片、乳腺活检和 0 到 II 期肿瘤的平稳或上升趋势，但并未影响所有年龄组的 III 期和 IV 期肿瘤的上升趋势。III期或IV期肿瘤的增加趋势在所有年龄组的总时间序列中保持增加。结论：大流行改变了乳腺 X 线照片、乳腺活检和 0 到 II 期肿瘤的平稳或上升趋势，但并未影响所有年龄组的 III 期和 IV 期肿瘤的上升趋势。