著者
Tatsuhiko Anzai Keisuke Fukui Tsubasa Ito Yuri Ito Kunihiko Takahashi
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
pp.JE20200443, (Released:2020-12-12)
参考文献数
34
被引用文献数
2 22

Background: Suicide amidst the coronavirus disease (COVID-19) pandemic is an important issue. In Japan, the number of suicides in April 2020 decreased by nearly 20% from that in 2019. To assess the impact of an infectious disease pandemic, excess mortality is often discussed. Our main purpose was evaluating excess mortality from suicide in Japan during the early pandemic period.Methods: We used data on suicides collected by the National Police Agency of Japan until June 2020. We estimated excess mortality during the early pandemic period (March–June 2020) using a time-series model of the number of suicides before the pandemic. A quasi-Poisson model was employed for the estimation. We evaluated excess mortalities by the categories of age and sex, and prefectures.Results: No significant excess mortality was observed throughout the early pandemic; instead, a downward trend in the number of suicides for both sexes was noted. For males, negative values of excess mortalities below the lower bound of the 95% prediction interval were observed in April and May. All numbers of females during the period were included in the interval, and the excess mortalities in June were positive and higher than those in April and May. In Tokyo, the number of suicides was below the lower bound throughout the period.Conclusion: Our results suggest that various changes such as communication, and social conditions amid the early COVID-19 pandemic induced a decrease in suicides in Japan. However, continuous monitoring is needed to evaluate the long-term effects of the pandemic on suicides.
著者
Masahiko Gosho Tomohiro Ohigashi Kengo Nagashima Yuri Ito Kazushi Maruo
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
pp.JE20210089, (Released:2021-09-25)
参考文献数
46
被引用文献数
7

Background: Logistic regression models are widely used to evaluate the association between a binary outcome and a set of covariates. However, when there are few study participants at the outcome and covariate levels, the models lead to bias of the odds ratio (OR) estimated using the maximum likelihood (ML) method. This bias is known as sparse data bias, and the estimated OR can yield impossibly large values because of data sparsity. However, this bias has been ignored in most epidemiological studies.Methods: We review several methods for reducing sparse data bias in logistic regression. The primary aim is to evaluate the Bayesian methods in comparison with the classical methods, such as the ML, Firth’s, and exact methods using a simulation study. We also apply these methods to a real data set.Results: Our simulation results indicate that the bias of the OR from the ML, Firth’s, and exact methods is considerable. Furthermore, the Bayesian methods with hyper-g prior modeling of the prior covariance matrix for regression coefficients reduced the bias under the null hypothesis, whereas the Bayesian methods with log F-type priors reduced the bias under the alternative hypothesis.Conclusion: The Bayesian methods using log F-type priors and hyper-g prior are superior to the ML, Firth’s, and exact methods when fitting logistic models to sparse data sets. The choice of a preferable method depends on the null and alternative hypothesis. Sensitivity analysis is important to understand the robustness of the results in sparse data analysis.
著者
Kota Katanoda Megumi Hori Eiko Saito Akiko Shibata Yuri Ito Tetsuji Minami Sayaka Ikeda Tatsuya Suzuki Tomohiro Matsuda
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
vol.31, no.7, pp.426-450, 2021-07-05 (Released:2021-07-05)
参考文献数
91
被引用文献数
64

Background: Unlike many North American and European countries, Japan has observed a continuous increase in cancer incidence over the last few decades. We examined the most recent trends in population-based cancer incidence and mortality in Japan.Methods: National cancer mortality data between 1958 and 2018 were obtained from published vital statistics. Cancer incidence data between 1985 and 2015 were obtained from high-quality population-based cancer registries maintained by three prefectures (Yamagata, Fukui, and Nagasaki). Trends in age-standardized rates (ASR) were examined using Joinpoint regression analysis.Results: For males, all-cancer incidence increased between 1985 and 1996 (annual percent change [APC] +1.1%; 95% confidence interval [CI], 0.7–1.5%), increased again in 2000–2010 (+1.3%; 95% CI, 0.9–1.8%), and then decreased until 2015 (−1.4%; 95% CI, −2.5 to −0.3%). For females, all-cancer incidence increased until 2010 (+0.8%; 95% CI, 0.6–0.9% in 1985–2004 and +2.4%; 95% CI, 1.3–3.4% in 2004–2010), and stabilized thereafter until 2015. The post-2000 increase was mainly attributable to prostate in males and breast in females, which slowed or levelled during the first decade of the 2000s. After a sustained increase, all-cancer mortality for males decreased in 1996–2013 (−1.6%; 95% CI, −1.6 to −1.5%) and accelerated thereafter until 2018 (−2.5%; 95% CI, −2.9 to −2.0%). All-cancer mortality for females decreased intermittently throughout the observation period, with the most recent APC of −1.0% (95% CI, −1.1 to −0.9%) in 2003–2018. The recent decreases in mortality in both sexes, and in incidence in males, were mainly attributable to stomach, liver, and male lung cancers.Conclusion: The ASR of all-cancer incidence began decreasing significantly in males and levelled off in females in 2010.
著者
Masato Ota Kohei Taniguchi Mitsuhiro Asakuma Sang-Woong Lee Yuri Ito
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
pp.JE20220347, (Released:2023-12-02)
参考文献数
28

Background: The COVID-19 pandemic has affected cancer care. The aim of this study was to clarify the trend of colorectal cancer (CRC) stage distribution in Japan during the COVID-19 pandemic.Methods: In this retrospective study, we used an inpatient medical claims database established at approximately 400 acute care hospitals. From the database, we searched patients who were identified as having the main disease (using ICD-10codes [C18.0–C20]) between January 2018 and December 2020. A multivariate logistic regression analysis was used to determine the impact of the pandemic on CRC stage distribution each month, and the odds ratio (OR) for late-stage cancer was calculated.Results: We analyzed 99,992 CRC patients. Logistic regression analysis, including the interaction term between increased late-stage CRC effect during the pandemic period and by each individual month, showed that the OR for late-stage CRC was highest in July during the pandemic, at 1.31 (95%CI: 1.13– 1.52) and also significantly higher in September at 1.16 (95%CI: 1.00– 1.35).Conclusion: We investigated the trend of CRC stage distribution during the COVID-19 pandemic using a nationwide hospital-claims database in Japan, and found that the proportion of early-stage cancers tended to decrease temporarily after the state of emergency declaration due to the COVID-19 pandemic, but the effect was only temporary.
著者
Noriko Kaneko Yoshikazu Nishino Yuri Ito Tomoki Nakaya Seiki Kanemura
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
vol.33, no.10, pp.521-530, 2023-10-05 (Released:2023-10-05)
参考文献数
35
被引用文献数
1

Background: Previous studies have shown that socioeconomic factors are associated with cancer incidence and stage at diagnosis; however, relevant findings in Japan are limited. We examined the association between socioeconomic status and cancer incidence, stage at diagnosis, and detection status by screening, as assessed using the areal deprivation index (ADI), in population-based cancer registry data.Methods: A total of 79,816 cases, including stomach, colorectal, lung, female breast, and cervical cancer diagnosed in Miyagi Prefecture between 2005 and 2010, were analyzed. After calculating the ADI at the place of residence in each case, we examined the association between quintiles of ADI and age-adjusted incidence rates of all stages and advanced stages by sex and site using Poisson regression analysis. The association between the ADI and the proportion of screen-detected cancers was also examined using logistic regression analysis.Results: The age-adjusted incidence rates of all sites and lung cancer in men and lung cancer and cervical cancer in women tended to increase significantly in areas with a higher ADI. The age-adjusted incidence rates of advanced-stage cancers were significantly higher for all sites and lung cancer in both sexes, and for stomach and colorectal cancer in men. The proportion of screen-detected cancer tended to be significantly lower in areas with a higher ADI for stomach and colorectal cancer in men.Conclusion: Our results indicate that socioeconomic disparities may affect cancer incidence and early diagnosis in Japan. These results suggest the importance of cancer control measures targeting people with low socioeconomic status in Japan.
著者
Noriko Kaneko Yoshikazu Nishino Yuri Ito Tomoki Nakaya Seiki Kanemura
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
pp.JE20220066, (Released:2022-07-16)
参考文献数
35
被引用文献数
1

Background: Previous studies have shown that socioeconomic factors are associated with cancer incidence and stage at diagnosis; however, relevant findings in Japan are limited. We examined the association between socioeconomic status and cancer incidence, stage at diagnosis, and detection status by screening, as assessed by the areal deprivation index (ADI), using population-based cancer registry data.Methods: A total of 79,816 cases including stomach, colorectal, lung, female breast, and cervical cancer diagnosed in Miyagi Prefecture between 2005 and 2010 were analyzed. After calculating the ADI at the place of residence in each case, we examined the association between quintiles of ADI and age-adjusted incidence rates of all stages and advanced stages by sex and site using Poisson regression analysis. The association between the ADI and the proportion of screen-detected cancers was also examined using logistic regression analysis.Results: The age-adjusted incidence rates of all sites and lung cancer in men and lung cancer and cervical cancer in women tended to increase significantly in areas with a higher ADI. The age-adjusted incidence rates of advanced-stage cancers were significantly higher for all sites and lung cancer in both sexes, and stomach and colorectal cancer in men. The proportion of screen-detected cancer tended to be significantly lower in areas with a higher ADI for stomach and colorectal cancer in men.Conclusion: Our results indicate that socioeconomic disparities may affect cancer incidence and early diagnosis in Japan. These results suggest the importance of cancer control measures targeting people with low socioeconomic status in Japan.
著者
Tatsuhiko Anzai Keisuke Fukui Tsubasa Ito Yuri Ito Kunihiko Takahashi
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
vol.31, no.2, pp.152-156, 2021-02-05 (Released:2021-02-05)
参考文献数
34
被引用文献数
22

Background: Suicide amidst the coronavirus disease (COVID-19) pandemic is an important issue. In Japan, the number of suicides in April 2020 decreased by nearly 20% from that in 2019. To assess the impact of an infectious disease pandemic, excess mortality is often discussed. Our main purpose was evaluating excess mortality from suicide in Japan during the early pandemic period.Methods: We used data on suicides collected by the National Police Agency of Japan until June 2020. We estimated excess mortality during the early pandemic period (March–June 2020) using a time-series model of the number of suicides before the pandemic. A quasi-Poisson model was employed for the estimation. We evaluated excess mortalities by the categories of age and sex, and by prefecture.Results: No significant excess mortality was observed throughout the early pandemic; instead, a downward trend in the number of suicides for both sexes was noted. For males, negative values of excess mortalities below the lower bound of the 95% prediction interval were observed in April and May. All numbers of females during the period were included in the interval, and the excess mortalities in June were positive and higher than those in April and May. In Tokyo, the number of suicides was below the lower bound throughout the period.Conclusion: Our results suggest that various changes, such as communication, and social conditions amid the early COVID-19 pandemic induced a decrease in suicides in Japan. However, continuous monitoring is needed to evaluate the long-term effects of the pandemic on suicides.