[Abstract translations] J EPIDEMIOL, 31(4); 2021

To get a quick overview of the issue and survey current topics across the field, I translate the titles and abstracts of the open-access Journal of Epidemiology into Japanese. Because the goal is a general overview, I post these DeepL translations largely as-is.

Update (May 8, 2021)

I learned that official Japanese highlights are available here.

You can read the monthly Japanese highlights for the Japan Epidemiological Association's English-language journal (Journal of Epidemiology) here. I had no idea. https://t.co/aHUkv0PPX0

— Shoei (@shoei05) May 8, 2021

Volume 31(4); 2021

https://www.ncbi.nlm.nih.gov/pmc/issues/376933/

Original Articles

Determinants of the difference in gastric cancer survival between Japan and the United States using national databases

Ito Y, Miyashiro I, Ishikawa T, et al. Determinant Factors on Differences in Survival for Gastric Cancer Between the United States and Japan Using Nationwide Databases. J Epidemiol. 2021;31(4):241-248. doi:10.2188/jea.JE20190351

Background
Although gastric cancer incidence and mortality are declining, it remains a global public health issue. International studies have reported higher survival rates in South Korea and Japan than in other countries, including the United States. We examined the determinants of the higher survival rate in Japan compared with the United States.

Methods
We analyzed data on 78,648 cases from the Japanese Gastric Cancer Association (JGCA), a nationwide gastric cancer registry project conducted from 2004 to 2007, and compared them with data on 16,722 cases from the Surveillance, Epidemiology, and End Results Program (SEER), a population-based cancer registry in the United States, from 2004 to 2010. We estimated 5-year relative survival rates and applied a multivariable excess hazard model accounting for the number of examined lymph nodes (LNs) to compare Japan and the United States.

Results
The 5-year relative survival rate was 81.0% in Japan and 45.0% in the United States. Even after accounting for confounding factors, Japan showed a significantly higher survival rate. Among N2 patients, a greater number of examined LNs was associated with higher survival in both Japan and the United States. Among N3 patients, the relationship between the survival difference between the two countries and the number of examined LNs disappeared.

Conclusion
The large difference in GC survival between Japan and the United States can be largely explained by differences in stage at diagnosis, though the number of examined LNs, in relation to stage migration, may also help explain the gap between the two countries.

Effects of smoking and sex on the association between long-term alcohol consumption and metabolic syndrome in middle-aged and older adults

Lee K, Giovannucci EL, Kim J. The Effect of Smoking and Sex on the Association Between Long-term Alcohol Consumption and Metabolic Syndrome in a Middle-aged and Older Population. J Epidemiol. 2021;31(4):249-258. doi:10.2188/jea.JE20190328

Background
The effects of smoking and sex on the relationship between alcohol consumption and the risk of developing metabolic syndrome (MetS) and its components have not yet been investigated.

Methods
We recruited 5,629 Korean adults aged 40–69 years without metabolic syndrome at baseline. Alcohol consumption was assessed every 2 years, and participants were classified as abstainers, light, moderate, or heavy drinkers. Smoking status was surveyed at baseline and classified into non-smokers and current smokers. Using multivariable Cox proportional hazards models, we examined the risk of developing MetS and its components according to alcohol consumption by smoking status and sex.

Results
During 12 years of follow-up, 2,336 participants (41.5%) developed MetS. Among non-smokers, light or moderate drinkers had a lower risk of developing MetS, abdominal obesity, hyperglycemia, hypertriglyceridemia, and low HDL-C compared with abstainers. Heavy alcohol consumption was found to increase the risk of developing elevated blood pressure in men (hazard ratio [HR] 1.48; 95% confidence interval [CI], 1.07-2.06; P = 0.020) and abdominal obesity in women (HR 1.86; 95% CI, 1.06-3.27; P = 0.030). Among smokers, however, no inverse association was observed between light or moderate alcohol consumption and hypertriglyceridemia or abdominal obesity, whereas a positive association was observed between heavy alcohol consumption and hyperglycemia (HR 1.39; 95% CI, 1.07-1.80; P = 0.014).

Conclusion
Smoking status and sex strongly influence the dose-dependent association between long-term alcohol consumption and MetS and its components.

Disparities between family-performed cardiopulmonary resuscitation and non-family-performed cardiopulmonary resuscitation

Background
Bystander cardiopulmonary resuscitation (BCPR) plays a vital role in lifesaving treatment for out-of-hospital cardiac arrest, yet little is known about the relationship between bystanders and patients in actual settings. This study aimed to evaluate disparities between BCPR performed by family members and BCPR performed by non-family members.

Methods
This population-based observational study included all adult patients with witnessed out-of-hospital cardiac arrest (OHCA) of medical origin in Niigata City, Japan, between January 2012 and December 2016, following the Utstein style. Logistic regression analysis was used to evaluate the association between the type of witness and the probability of providing BCPR. Next, among those who received BCPR, we examined differences between family-performed BCPR and non-family-performed BCPR regarding whether the person who witnessed the cardiac arrest actually performed the BCPR.

Results
During the study period, 818 patients were eligible for this analysis: 609 (74.4%) were witnessed by family members, and 209 (25.6%) were witnessed by non-family members. Multivariable logistic regression analysis showed that OHCA patients witnessed by family members were less likely to receive BCPR than those witnessed by non-family members (260/609 [42.7%] vs. 119/209 [56.9%], P = 0.017). Among witnessed cases in which BCPR was performed, the proportion of BCPR actually performed by the witnessing family member was lower than that performed by the witnessing non-family member (242/260 [93.1%] vs. 116/119 [97.5%], P = 0.011).

Conclusion
This community-based observational study found that witnessing family members were less likely to perform BCPR than witnessing non-family members.

The role of social support in the relationship between economic burden and exercise frequency among older Japanese adults: a 19-year longitudinal study

Komazawa Y, Murayama H, Harata N, Takami K, Parady GT. Role of Social Support in the Relationship Between Financial Strain and Frequency of Exercise Among Older Japanese: A 19-year Longitudinal Study. J Epidemiol. 2021;31(4):265-271. doi:10.2188/jea.JE20190248

Background
Previous studies have reported that economic burden adversely affects health behaviors. Although social support is expected to buffer these effects, few studies have investigated its impact on exercise, and this study can deepen our understanding of the relationship between social support and physical activity or exercise. This study examined the relationship between economic burden and exercise frequency in old age, as well as the role of social support in this relationship.

Methods
Data were obtained from a 19-year longitudinal study conducted from 1987 to 2006 among Japanese adults aged 60 years and older, with up to 7 repeated observations. Exercise frequency was assessed on a 4-point scale. Economic burden was measured using responses to 3 questions regarding financial status. Both emotional support and instrumental support were considered in this study. Covariates included demographic and socioeconomic factors, health behaviors, and health status.

Results
The study included 3,911 participants. Generalized estimating equation models showed that among women, greater economic burden at the previous wave was associated with lower exercise frequency (b = -0.018; 95% confidence interval, -0.032 to -0.004), and as economic burden increased, those receiving more instrumental support showed a greater decrease in exercise than those receiving less support (b = -0.009; 95% confidence interval, -0.017 to -0.002). These relationships were not observed in men.

Conclusion
This study showed that economic burden was negatively associated with exercise frequency among older women. Furthermore, among women experiencing economic burden, instrumental support was negatively associated with exercise frequency.

Population attributable fractions of modifiable risk factors for nonsyndromic orofacial clefts: a prospective cohort study from the Japan Environment and Children's Study

Sato Y, Yoshioka E, Saijo Y, et al. Population Attributable Fractions of Modifiable Risk Factors for Nonsyndromic Orofacial Clefts: A Prospective Cohort Study From the Japan Environment and Children’s Study. J Epidemiol. 2021;31(4):272-279. doi:10.2188/jea.JE20190347

Background
The population impact of modifiable risk factors on orofacial clefts remains unclear. This study aimed to estimate the population attributable fractions (PAFs) of modifiable risk factors for nonsyndromic cleft lip with or without cleft palate (CL±P) and cleft palate only (CP) in Japan.

Methods
We conducted a prospective cohort study using data from the Japan Environment and Children's Study, which recruited pregnant women between 2011 and 2014. We estimated the PAFs of maternal alcohol consumption, psychological distress, maternal active and passive smoking, abnormal BMI (<18.5 kg/m2 and ≥25 kg/m2), and non-use of folic acid supplements during pregnancy for live births with nonsyndromic CL±P and CP.

Results
A total of 94,174 pairs of pregnant women and their singleton infants were included. Among them, there were 146 nonsyndromic CL±P cases and 41 nonsyndromic CP cases. The combined adjusted PAF of modifiable risk factors excluding maternal alcohol consumption for CL±P was 34.3%. Only maternal alcohol consumption was not associated with CL±P risk. The adjusted PAFs for CL±P of psychological distress, maternal active smoking, passive smoking, abnormal BMI, and non-use of folic acid supplements were 1.4% (95% confidence interval [CI], -10.7 to 15.1%), 9.9% (95% CI, -7.0 to 26.9%), 10.8% (95% CI, -9.9 to 30.3%), 2.4% (95% CI, -7.5 to 14.0%), and 15.1% (95% CI, -17.8 to 41.0%), respectively. For CP, PAFs could not be obtained due to the small sample size.

Conclusion
This study reported the impact of modifiable risk factors on CL±P, but not on CP. These findings should be useful in planning primary prevention for CL±P.

Physical fitness and dyslipidemia in Japanese adults: a cohort study from the Niigata Wellness Study

Momma H, Kato K, Sawada SS, et al. Physical Fitness and Dyslipidemia Among Japanese: A Cohort Study From the Niigata Wellness Study. J Epidemiol. 2021;31(4):287-296. doi:10.2188/jea.JE20200034

Background
Grip strength reflects overall muscle strength and muscle mass and has been reported to be associated with various metabolic variables. However, its prognostic association with dyslipidemia remains unclear. This study examined the associations of grip strength and other physical fitness markers with the incidence of dyslipidemia among Japanese adults.

Methods
The study included 16,149 Japanese adults (6,208 women) aged 20 to 92 years who underwent physical fitness tests between April 2001 and March 2002. Grip strength, vertical jump, single-leg balance with eyes closed, forward bending, and whole-body reaction time were assessed at baseline. Dyslipidemia was determined annually from April 2001 to March 2008 based on fasting serum lipid profiles and self-reported dyslipidemia.

Results
During the follow-up period, 4,458 men (44.9%) and 2,461 women (39.6%) developed dyslipidemia. In both men and women, higher relative grip strength (grip strength/body mass index) was associated with a lower incidence of dyslipidemia (P for trend <0.001). Compared with the first septile, the hazard ratios and 95% confidence intervals (CIs) for the seventh septile were 0.56 (95% CI, 0.50–0.63) in men and 0.69 (95% CI, 0.58–0.81) in women. In addition, relative vertical jump (vertical jump power/body mass index) was inversely associated with the incidence of dyslipidemia in both men and women (P for trend <0.001). No associations were observed between the other physical fitness measures and dyslipidemia in either sex.

Conclusions
Relative grip strength and vertical jump may serve as useful risk markers for the development of dyslipidemia.

Short Communication

The association between education and overall diet quality is explained by different food groups in middle-aged and older Japanese women

Hashimoto A, Murakami K, Kobayashi S, Suga H, Sasaki S. Associations of Education With Overall Diet Quality Are Explained by Different Food Groups in Middle-aged and Old Japanese Women. J Epidemiol. 2021;31(4):280-286. doi:10.2188/jea.JE20200030

Background
Disparities in overall diet quality by individual educational attainment have become a social issue. However, it remains unclear which food groups contribute to these disparities. This study examined which food groups explain the association between educational attainment and overall diet quality among Japanese women.

Methods
A total of 3,788 middle-aged women (mean age, 47.7 years) and 2,188 older women (mean age, 74.4 years) living in 47 prefectures in Japan provided data on educational attainment (low, middle, and high) and dietary intake assessed with a diet history questionnaire. Diet quality was scored from 0 to 70 points based on seven food components. After adjusting for lifestyle and neighborhood variables, general linear models were used to estimate mean diet quality scores by education level, followed by Dunnett's multiple comparison tests. Mean scores for each food component were also estimated by education level and compared using the same method.

Results
After adjusting for lifestyle and neighborhood variables, mean diet quality scores were higher among women with middle and high education than among those with low education in both age groups. Middle-aged women with middle and high education had higher scores for milk, snacks, confectioneries, and beverages, fruits, and vegetable dishes than those with low education. Older women with middle and high education had higher scores for sodium from seasonings and fruits than those with low education.

Conclusions
This study suggests that among middle-aged and older Japanese women, the positive association between education and diet quality is explained by different food groups, independent of lifestyle and neighborhood variables.