Journal of Epidemiology最新文献

Background: Acute pulmonary embolism (PE) is a life-threatening in-hospital complication. Recently, several studies have reported the clinical characteristics of PE among Japanese patients using the diagnostic procedure combination (DPC)/per diem payment system database. However, the validity of PE identification algorithms for Japanese administrative data is not yet clear. The purpose of this study was to evaluate the validity of using DPC data to identify acute PE inpatients.

Methods: The reference standard was symptomatic/asymptomatic PE patients included in the COntemporary ManageMent AND outcomes in patients with Venous ThromboEmbolism (COMMAND VTE) registry, which is a cohort study of acute symptomatic venous thromboembolism (VTE) patients in Japan. The validation cohort included all patients discharged from the six hospitals included in both the registry and DPC database. The identification algorithms comprised diagnosis, anticoagulation therapy, thrombolysis therapy, and inferior vena cava filter placement. Each algorithm's sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were estimated.

Results: A total of 43.4% of the validation cohort was female, with a mean age of 67.3 years. The diagnosis-based algorithm showed a sensitivity of 90.2% (222/246; 95% confidence interval [CI], 85.8-93.6%), a specificity of 99.8% (228,485/229,027; 95% CI, 99.7-99.8%), a PPV of 29.1% (222/764; 95% CI, 25.9-32.4%) and an NPV of 99.9% (228,485/229,509; 95% CI, 99.9-99.9%) for identifying symptomatic/asymptomatic PE. Additionally, 94.6% (159/168; 95% CI, 90.1-97.5%) of symptomatic PE patients were identified using the diagnosis-based algorithm.

Conclusion: The diagnosis-based algorithm may be a relatively sensitive method for identifying acute PE inpatients in the Japanese DPC database.

Background: In Japan, sentinel surveillance is used to monitor the trend of infectious gastroenteritis. Another method of pathogen surveillance, wastewater-based epidemiology, has been used recently because it can help to monitor infectious disease without relying on patient data. Here, we aimed to determine the viral trends reflected in the number of reported patients and number of gastroenteritis virus-positive samples. We focused on gastroenteritis viruses present in wastewater and investigated the usefulness of wastewater surveillance for the surveillance of infectious gastroenteritis.

Methods: Real-time polymerase chain reaction was used for viral gene detection in wastewater. The number of reported patients per pediatric sentinel site and number of viral genome copies were compared for correlation potential. The number of gastroenteritis virus-positive samples reported by National Epidemiological Surveillance of Infectious Disease (NESID) and the status of gastroenteritis viruses detected in wastewater were also evaluated.

Results: Genes of norovirus genotype I, norovirus genotype II, sapovirus, astrovirus, rotavirus group A, and rotavirus group C were detected in wastewater samples. Viruses were detected in wastewater during periods when no gastroenteritis virus-positive samples were reported to NESID.

Conclusion: Norovirus genotype II and other gastroenteritis viruses were detected in wastewater even during periods when no gastroenteritis virus-positive samples were found. Therefore, surveillance using wastewater can complement sentinel surveillance and is an effective tool for the surveillance of infectious gastroenteritis.

Background: Little is known about the trends of imported infectious diseases among travelers to non-endemic countries during the novel coronavirus disease 2019 (COVID-19) pandemic. This article aimed to describe those among travelers to Japan.

Methods: This is a descriptive study based on national surveillance data. Imported infectious disease cases were defined as those with a reported overseas source of infection among 15 diseases pre-selected based on the probability and impact of importation. The number of notified cases from April 2016 to March 2021 were described by disease and time of diagnosis. The relative ratio and absolute difference in case counts-both by number and per arrival-were calculated by disease comparing those from the pandemic period (April 2020-March 2021) to the pre-pandemic period (April 2016-March 2020).

Results: A total of 3,524 imported infectious disease cases were diagnosed during the study period, including 3,439 cases before and 85 cases during the pandemic. The proportionate distribution of diseases changed but notification counts of all 15 diseases decreased during the pandemic. Accounting for arrivals, however, seven diseases showed a two-fold or greater increase, with a notable absolute increase per million arrivals for amebiasis (60.1; 95% confidence interval [CI], 41.5-78.7), malaria (21.7; 95% CI, 10.5-33.0), and typhoid fever (9.3; 95% CI, 1.9-16.8).

Conclusion: The epidemiology of imported infectious diseases changed during the pandemic. While the number of imported infectious disease cases decreased, the number of cases per arrivals increased considerably both in relative and absolute terms for several diseases of public health and clinical importance.

Background: Behavioral and psychological symptoms of dementia (BPSD) are common among people with dementia from the early stages and can appear even in mild cognitive impairment (MCI). However, the prognostic impact of BPSD is unclear. This study examined the association between BPSD and mortality among people with cognitive impairment.

Methods: This longitudinal study involved 1,065 males and 1,681 females (mean age: males = 77.1 years; females = 78.6 years) with MCI or dementia diagnosis, from the National Center for Geriatrics and Gerontology-Life Stories of People with Dementia (NCGG-STORIES), a single-center memory clinic-based cohort study in Japan that registered first-time outpatients from 2010–2018. Information about death was collected through a mail survey returned by participants or their close relatives, with an up to 8-year follow-up. BPSD was assessed using the Dementia Behavior Disturbance Scale (DBD) at baseline.

Results: During the follow-up period, 229 (28.1%) male and 254 (15.1%) female deaths occurred. Cox proportional hazards regression analysis showed that higher DBD scores were significantly associated with increased mortality risk among males, but not females (compared with the lowest quartile score group, hazard ratios [95% confidence intervals] for the highest quartile score group = 1.59 [1.11–2.29] for males and 1.06 [0.66–1.70] for females). Among the DBD items, lack of interest in daily living, excessive daytime sleep, and refusal to receive care had a higher mortality risk.

Conclusions: The findings suggest a potential association between BPSD and poor prognosis among males with cognitive impairment.

Background: This study aimed to develop and validate claims-based algorithms for identifying hospitalized patients with coronavirus disease (COVID-19) and the disease severity.

Methods: We used claims data including all patients at the National Center for Global and Medicine Hospital between January 1, 2020, and December 31, 2021. The claims-based algorithms for three statuses with COVID-19 (hospitalizations, moderate or higher status, and severe status) were developed using diagnosis codes (ICD-10 code: U07.1, B34.2) and relevant medical procedure code. True cases were determined using the COVID-19 inpatient registry and electronic health records. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each algorithm at 6-month intervals.

Results: Of the 75,711 total patients, number of true cases was 1,192 for hospitalizations, 622 for moderate or higher status, and 55 for severe status. The diagnosis code-only algorithm for hospitalization had sensitivities 90.4% to 94.9% and PPVs 9.3% to 19.4%. Among the algorithms consisting of both diagnosis codes and procedure codes, high sensitivity and PPV were observed during the following periods; 93.9% and 97.1% for hospitalization (January-June 2021), 90.4% and 87.5% for moderate or higher status (July-December 2021), and 92.3% and 85.7% for severe status (July-December 2020), respectively. Almost all algorithms had specificities and NPVs of approximately 99%.

Conclusions: The diagnosis code-only algorithm for COVID-19 hospitalization showed low validity throughout the study period. The algorithms for hospitalizations, moderate or higher status, and severe status with COVID-19, consisting of both diagnosis codes and procedure codes, showed high validity in some periods.

Background: The number of methamphetamine-related deaths has been increasing in recent decades. However, current data primarily rely on a few large-scale national surveys, highlighting the need for diverse data sources. Post-mortem studies offer advantages that compensate for the limitations of cohort studies. In this study, we aimed to (1) examine mortality rates and years of potential life lost, (2) compare proportionate mortality with previous cohort studies, and (3) quantitatively investigate causes of death as potential risk factors associated with each manner of death.

Methods: We analyzed 740 cases from 2013 to 2019 in Taiwan.

Results: The mean age of cases was 38.4 years, with a notable loss of 30s years of potential life, and 79.6% were male. The crude mortality rate was 0.45 per 100,000 person-years. The proportionate mortality indicated that autopsy dataset, compared to cohort studies, provided more accurate estimations for accidental deaths, equivalent suicides, underestimated natural deaths, and overestimated homicides. Accidental deaths were evident in 67% of cases with 80% attributed to drug intoxication. Multiple substances were detected in 61% of cases, with psychiatric medications detected in 43% of cases. Higher methamphetamine concentrations and a greater proportion of multiple substances and benzodiazepines were detected in suicidal deaths. Among accidental deaths, traffic accidents (7.9%) were the second most common cause, particularly motorcycle riders.

Conclusions: Using autopsy dataset as a secondary source, we identified that over half of the cases involved accidental drug intoxication. The significant proportion of cases involving multiple substances, psychiatric medications, and drug-impaired driving raises concerning.

Background: In Japan, few studies have examined suicide risk for five-year relative survival rates for cancer sites. Since five-year relative survival rates differ by sex, we aim to examine suicide risk for patients with cancer separately for men and women.

Methods: We estimated the risk of suicide among patients with cancer by sex in Japan compared to the general population, using standardized mortality ratios (SMRs). Patients with cancer diagnosed between January 1, 1985–December 31, 2013 and registered in the Osaka Cancer Registry were followed-up with for up to 10 years. The outcome was suicide death. In addition, cancer sites were classified into three prognosis groups based on five-year relative survival rates: good (> 70%), moderate (40–70%), poor (< 40%).

Results: Among 623 995 patients with cancer observed for 2 349 432 person-years, 1210 patients died by suicide (867 men and 343 women). The SMRs were almost equal for men (1.66, 95% CI, 1.55-1.77) and women (1.65, 95% CI, 1.48-1.83). SMRs for cancer prognosis groups were 1.01 (95% CI, 0.84-1.22) for men and 1.47 (95% CI, 1.24-1.73) for women in the good group, 1.53 (95% CI, 1.39-1.68) for men and 1.74 (95% CI, 1.47-2.05) for women in the moderate group, and 2.54 (95% CI, 2.27-2.85) for men and 1.87 (95% CI, 1.43-2.46) for women in the poor group.

Conclusions: In this population, both sexes had higher suicide risk with poor prognosis, but the difference in SMRs between the good and poor groups was smaller for women than men.

Background Previous studies have suggested that employment insecurity is associated with adverse health outcomes. We explored the association between temporary employment and smoking behaviors.

Methods We analyzed 11,795 workers (51,867 observations) from the Korea Health Panel Study (2009–2018). Employment types were categorized as regular, fixed-term, or daily, based on the duration of labor contract. The outcomes were current smoking status and changes in smoking behavior (initiation or cessation) in the following year. Generalized estimating equations were used to estimate odds ratio (OR) and 95% confidence interval (CI).

Results The proportions of fixed-term and daily workers were 41.2% and 16.4% for women and 23.6% and 12.4% for men, respectively. Temporary employment was associated with increased odds of current smoking, while also demonstrating prospective associations with changes in smoking behaviors. For instance, in prospective analyses, male workers with fixed-term and daily employments were associated with a decreased likelihood of smoking cessation (OR:0.77; 95% CI:0.65–0.91 for fixed-term employment and OR:0.66; 95% CI:0.52–0.83 for daily employment) in the following year compared to those with regular employment. Moreover, those experiencing consecutive temporary employment was most inversely associated with smoking cessation in both men (OR:0.56; 95% CI:0.44–0.71) and women (OR:0.37; 95% CI:0.16–0.85) compared to those experiencing consecutive regular employment. However, no clear association between temporary employment and smoking initiation was observed in both men and women.

Conclusions Temporary employment is directly associated with current smoking and inversely associated with smoking cessation. Policies are needed to improve job insecurity among temporary employees.

Background: For therapeutic efficacy, molnupiravir and nirmatrelvir-ritonavir must be started to treat patients within 5 days of disease onset to treat patients with novel coronavirus disease 2019 (COVID-19). However, some patients spend more than 5 days from disease onset before reporting to the Public Health Office. This study aimed to clarify the characteristics of patients with reporting delay.

Methods: This study included data from 12,399 patients with COVID-19 who reported to the Public Health Office from March 3^rd, 2021 to June 30^th, 2021. Patients were stratified into "linked" (n = 7,814) and "unlinked" (n = 4,585) cases depending on whether they were linked to other patients. A long reporting delay was defined as the difference between the onset and reporting dates of 5 days or more. Univariate and multivariate analyses were performed using log-binomial regression to identify factors related to long reporting delay, and prevalence ratios with corresponding 95% confidence intervals were calculated.

Results: The proportion of long reporting delay was 24.4% (1,904/7,814) and 29.3% (1,344/4,585) in linked and unlinked cases, respectively. Risks of long reporting delay among linked cases were living alone and onset on the day with a higher 7-day daily average confirmed cases or onset on weekends; whereas, risks for unlinked cases were age over 65 years, without occupation, and living alone.

Conclusion: Our results suggest the necessity to establish a Public Health Office system that is less susceptible to the rapid increase in the number of patients, promotes educational activities for people with fewer social connections, and improves access to health care.

Background: Many epidemiological studies have investigated dietary intake of antioxidant vitamins in relation to prostate cancer risk in Western countries, but the results are inconsistent. However, few studies have reported this relationship in Asian countries.

Methods: We investigated the association between intake of vitamins, including lycopene, α-carotene, β-carotene, vitamin C, vitamin E, with prostate cancer risk in the Japan Public Health Center-based Prospective (JPHC) study. 40,720 men without history of cancer finished the food frequency questionnaire (FFQ) and were included in the study. Hazard ratios (HRs) and 95% confidence intervals (CIs) of prostate cancer risk were calculated according to the quintiles of energy-adjusted intake of vitamins using Cox models.

Results: After an average of 15.2 years (617,599 person-years in total) of follow-up, 1,386 cases of prostate cancer were identified, including 944 localized cases and 340 advanced cases. No associations were observed in consumption of antioxidant vitamins, including α-carotene, β-carotene, vitamin C, and vitamin E, and prostate cancer risk. Although higher lycopene intake was associated with increased risk of prostate cancer (highest vs lowest quintile, HR 1.24; 95% CI, 1.04-1.47; P for trend = 0.01), there was a null association of lycopene intake with risk of prostate cancer detected by subjective symptoms (HR 1.12; 95% CI, 0.79-1.58; P for trend = 0.11).

Conclusion: Our study suggested no association between antioxidant intake of vitamins and prostate cancer risk.