Journal of Epidemiology
Online ISSN : 1349-9092
Print ISSN : 0917-5040
ISSN-L : 0917-5040
Volume 26, Issue 1
Displaying 1-9 of 9 articles from this issue
Original Article
  • Takeo Fujiwara, Yui Yamaoka, Naho Morisaki
    2016 Volume 26 Issue 1 Pages 4-13
    Published: January 05, 2016
    Released on J-STAGE: January 05, 2016
    Advance online publication: December 05, 2015
    Supplementary material
    Background: To estimate the prevalence of shaking and smothering and to determine risk factors in a population-based sample of mothers with 4-month-old infants in Japan.
    Methods: We administered a questionnaire to women who participated in a 4-month health checkup program in Aichi Prefecture, Japan (n = 6487; valid response rate, 66.8%), and assessed frequency of shaking and smothering during the past 1 month, as well as maternal, infant, and familial characteristics. Associations of shaking, smothering, and either shaking or smothering with possible risk factors were analyzed using multiple logistic regression.
    Results: Self-reported prevalence of shaking, smothering, and either shaking or smothering at least once during the past month was 3.9% (95% confidence interval [CI], 3.5%–4.4%), 2.7% (95% CI, 2.3%–3.1%), and 5.4% (95% CI, 4.9%–6.0%) respectively. Several different risk factors were found for shaking and smothering. Risk factors for either shaking or smothering were age 34 years or younger (especially 24 years or younger), age 40 years or older, full-time working, later attendance at 4-months health checkup, primiparity, living in a detached house, living on the 2nd floor or higher (especially on the 10th floor or higher), economic adversity, perceived excessive crying, and postpartum depression. Protective factors against infant abuse were living in a four-room house and having a larger number of people to consult with.
    Conclusions: Self-reported prevalences of shaking and smothering among mothers in Japan were similar to prevalences reported in western countries. These finding may be useful for identifying mothers at increased risk of shaking and smothering their infants.
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  • Takahiro Tabuchi, Masakazu Nakamura, Tomio Nakayama, Isao Miyashiro, J ...
    2016 Volume 26 Issue 1 Pages 14-21
    Published: January 05, 2016
    Released on J-STAGE: January 05, 2016
    Advance online publication: August 15, 2015
    Supplementary material
    Background: Longitudinal assessment of the impact of tobacco price on smoking cessation is scarce. Our objective was to investigate the effect of a price increase in October 2010 on cessation rates according to gender, age, socioeconomic status, and level of tobacco dependence in Japan.
    Methods: We used longitudinal data linkage of two nationally representative studies and followed 2702 smokers for assessment of their cessation status. The odds ratios (ORs) for cessation were calculated using logistic regression. To estimate the impact of the 2010 tobacco price increase on cessation, data from 2007 were used as a reference category.
    Results: Overall cessation rates significantly increased from 2007 to 2010, from 3.7% to 10.7% for men and from 9.9% to 16.3% for women. Cessation rates were 9.3% for men who smoked 1–10 cigarettes per day, 2.7% for men who smoked 11–20 cigarettes per day, and 2.0% for men who smoked more than 20 cigarettes per day in 2007. These rates increased to 15.5%, 10.0%, and 8.0%, respectively, in 2010. The impact was stronger among subjects who smoked more than 11 cigarettes per day than those who smoked 1–10 cigarettes per day in both sexes: ORs for 2010 were 4.04 for those smoking 11–20 cigarettes per day, 4.26 for those smoking more than 20 cigarettes per day, and 1.80 for those smoking 1–10 cigarettes per day in the main model in men. There were no obvious differences in the relationship between tobacco price increase and smoking cessation across age and household expenditure groups.
    Conclusions: The tobacco price increase in Japan had a significant impact on smoking cessation in both sexes, especially among heavy smokers, with no clear difference in effect by socio-demographic status.
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  • Hea Young Oh, Mi Kyung Kim, Sang-Soo Seo, Jae-Kwan Lee
    2016 Volume 26 Issue 1 Pages 22-29
    Published: January 05, 2016
    Released on J-STAGE: January 05, 2016
    Advance online publication: October 03, 2015
    Supplementary material
    Background: Cigarette smoking and oral contraceptive (OC) use have been associated with cervical neoplasia, and the combination of smoking and OC use could influence cervical carcinogenesis. We aimed to assess the joint effect of smoking and OC use on the risk of cervical intraepithelial neoplasia (CIN).
    Methods: From a cohort of human papillomavirus-positive subjects recruited from 6 hospitals in Korea from March 2006 to November 2012, a total of 678 subjects (411 control, 133 CIN 1, and 134 CIN 2 or 3 cases) were selected for this study (mean age, 43 years). The risk of CIN associated with smoking and OC use on additive and multiplicative scales was estimated via multinomial logistic regression after adjustment for potential confounding factors. The relative excess risk due to interaction (RERI) and the synergy index (S) were used to evaluate the additive interaction.
    Results: OC users (odds ratio [OR] 1.98; 95% confidence interval [CI], 1.07–3.69) and long-term OC use (≥20 months; OR 2.71; 95% CI, 1.11–6.59) had a higher risk of CIN 2/3, but had no association with CIN 1, compared to non-OC users. Smokers and heavy smoking (≥8 cigarettes/day) were not associated with any CIN grade. Combined smoking and OC use (OR 4.91; 95% CI, 1.68–14.4; RERI/S, 3.77/27.4; P for multiplicative interaction = 0.003) and combined heavy smoking and long-term OC use (OR 11.5; 95% CI, 1.88–70.4; RERI/S, 9.93/18.8; P for multiplicative interaction = 0.009) had a higher risk of CIN 2/3 but had no association with CIN 1 compared to combined non-smoking and non-OC use.
    Conclusions: OC use and smoking acted synergistically to increase the risk of CIN 2 or 3 in Korean women.
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  • Yasufumi Matsuda, Tatsuhiko Kubo, Yoshihisa Fujino, Shinya Matsuda, Fu ...
    2016 Volume 26 Issue 1 Pages 30-35
    Published: January 05, 2016
    Released on J-STAGE: January 05, 2016
    Advance online publication: November 14, 2015
    Background: Few studies have assessed whether treatment of acute cervical spinal cord injury (SCI) patients contributes to depression.
    Methods: Using an administrative database, we assessed patients for whom the diagnosis was unspecified injuries of cervical spinal cord (International Classification of Diseases and Injuries-10th (ICD-10) code; S14.1). We categorized patients with codes for depressive episode (ICD-10 code; F32) or recurrent depressive disorder (F33), or those prescribed antidepressants (tricyclic, tetracyclic, Selective Serotonin Reuptake Inhibitors, Serotonin Noradrenaline Reuptake Inhibitors, Trazodone, Sulpiride, or Mirtazapine) as having a depressive state. We compared the rate of each acute treatment between the depressive state group and the non-depressive state group using chi-square tests, and a multiple logistic regression model was used to identify the association between the acute treatment and depressive state.
    Results: There were 151 patients who were judged to be in a depressive state, and the other 2115 patients were categorized into the non-depressive state group. Intervention of intravenous anesthesia, tracheostomy, artificial respiration, and gastrostomy had a significant positive correlation with depressive state. Multiple logistic regression analysis showed that tracheostomy (odds ratio [OR] 2.18; 95% confidence interval [CI], 1.09–4.38) and artificial respiration (OR 2.28; 95% CI, 1.32–3.93) were significantly associated with depressive state, and men had a 36% reduction in the risk of depressive state compared with women (OR 0.64; 95% CI, 0.44–0.94), whereas age, wound-treatment, all of the orthopedic procedures, intravenous anesthesia, and gastrostomy were not associated with depressive state.
    Conclusions: These findings suggest that tracheostomy, artificial respiration and female gender in the acute phase after cervical SCI might be associated with the development of depression.
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  • Motoki Iwasaki, Junko Ishihara, Ribeka Takachi, Hidemi Todoriki, Hiros ...
    2016 Volume 26 Issue 1 Pages 36-44
    Published: January 05, 2016
    Released on J-STAGE: January 05, 2016
    Advance online publication: August 15, 2015
    Supplementary material
    Background: Interest in the physiological roles of amino acids and their impact on health outcomes is substantial and growing. This interest has prompted assessment of the habitual intake of amino acids for use in epidemiologic studies and in clarifying the association between habitual intake and plasma levels of amino acids. Here, we investigated the validity of ranking individuals according to dietary amino acid intake as estimated using a food frequency questionnaire (FFQ) in comparison with intakes from dietary records (DRs) and plasma levels.
    Methods: A total of 139 men and women selected from examinees of the cancer screening program at the Research Center for Cancer Prevention and Screening, National Cancer Center, Japan, provided 4-day weighed DRs, a semi-quantitative FFQ, and plasma samples. Plasma levels of amino acids were measured using the UF-Amino Station system.
    Results: Spearman rank correlation coefficients of energy-adjusted intake of amino acids from the DR and FFQ ranged from 0.40 to 0.65 for men and from 0.35 to 0.46 for women. Correlation coefficients of energy-adjusted intake from the DR and plasma levels ranged from −0.40 to 0.25 for men and from −0.16 to 0.11 for women. Similarly, no significant positive correlation coefficients were observed between intake from the FFQ and plasma levels for either men or women.
    Conclusions: We confirmed that this FFQ has moderate validity in estimating amino acid intake when 4-day weighed DRs are used as a reference method, suggesting that it is suitable for ranking individuals living in urban areas in Japan by amino acid intake.
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Short Communication
  • Nargess Saiepour, Robert Ware, Jake Najman, Peter Baker, Alexandra Cla ...
    2016 Volume 26 Issue 1 Pages 45-49
    Published: January 05, 2016
    Released on J-STAGE: January 05, 2016
    Advance online publication: August 29, 2015
    Background: To identify patterns of loss to follow-up and baseline predictors of each pattern.
    Methods: The Mater-University Study of Pregnancy collected baseline information for 7718 pregnant women who attended Mater Hospital in Brisbane, Australia, from 1981 through 1983. Follow-up data for 6753 eligible participants were collected at 6 months, 5 years, 14 years, 21 years, and 27 years after giving birth. Participants were partitioned into groups of ‘Always Responders’, ‘Returners’, ‘Leavers’, ‘Intermittents’, and ‘Never Responders’. Multinomial logistic regression was used to simultaneously compare baseline characteristics of the last four groups with ‘Always Responders’.
    Results: Being younger, less educated, having no partner, and living in rented housing were associated with being a ‘Returner’. Not owning housing, receiving welfare benefits, and being younger, less educated, not married, a smoker, an Aboriginal/Islander, and born in a non-English-speaking country were associated with being a ‘Leaver’, an ‘Intermittent’, or a ‘Never-responder’. Having higher mental health score and drinking before pregnancy were associated with being a ‘Leaver’ or an ‘Intermittent’. Being unemployed and not physically active were associated with being a ‘Leaver’ or ‘Never Responder’. The groups ‘Leavers’ and ‘Never Responders’ were the most different from the ‘Always Responders’. The group that was most similar to ‘Always Responders’ was the ‘Returners’.
    Conclusions: Patterns of loss to follow-up should be considered in the application of missing data techniques, where researchers make assumptions about the characteristics of those subjects who do not respond to assess the type of missing data. This information can be used to prevent individuals who are at high risk of dropping out of a study from doing so.
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Study Profile
  • Hannae Jo, Sora Baek, Hee-won Park, Sang-Ah Lee, Jiyoung Moon, Jae E. ...
    2016 Volume 26 Issue 1 Pages 50-56
    Published: January 05, 2016
    Released on J-STAGE: January 05, 2016
    Advance online publication: August 01, 2015
    Background: The ongoing Farmers’ Cohort for Agricultural Work-related Musculoskeletal Disorders (FARM) study was developed to evaluate health status and related factors in farmers.
    Methods: Farmers in Kangwon Province, South Korea, were recruited. Baseline characteristics were determined using questionnaires about sociodemographic and health characteristics and agricultural work-related factors. In addition, laboratory examinations (lumbar spinal radiography and serologic testing) were conducted.
    Results: The FARM study covers eight rural areas and recruited 1013 subjects (534 women; mean [standard deviation {SD}] age, 57.2 [7.5] years). Musculoskeletal pain in multiple areas was reported by 925 subjects (91.3%), and low back pain (63.8%) was the most frequent site of pain. Farmer’s Stress Inventory (mean [SD], 77.7 [10.2]; range, 28–112] and subjective stress index (mean [SD], 5.3 [2.4]; range, 0–10) were above median scale values, reflecting a stressful condition, while the EuroQol-5D-3L index and the EuroQol-Visual Analog Scale scores were high (mean [SD], 0.9 [0.1]; range −0.171–1 and mean [SD], 67.7 [18.7]; range 0–100, respectively), reflecting good life quality. In total, 53% of participants had worked in farming for more than 30 years, and workers involved in dry-field farming comprised the largest subgroup (41.5%). Most participants (94.3%) had no more than a high school education, and families with annual income below 20 million won constituted the largest subgroup (36.3%).
    Conclusions: The FARM study may provide data on the current health status and related sociodemographic and agricultural work-related risk factors in Korean farmers, with the goal of providing a scientific basis for developing coping interventions and preventive strategies.
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