Background: Regular physical activity contributes to the prevention of cancer, cardiovascular disease, and other chronic diseases. However, the frequency of physical activity often declines with age, particularly among the elderly. Thus, we investigated the effects of daily walking on mortality among younger-elderly men (65–74 years) with or without major critical diseases (heart disease, cerebrovascular disease, or cancer). Methods: We assessed 1239 community-dwelling men aged 64/65 years from the New Integrated Suburban Seniority Investigation Project. We estimated hazard ratios (HRs) of all-cause mortality and 95% confidence intervals (CIs) according to daily walking duration and adjusted for potential confounders, including survey year, marital status, work status, education, smoking and drinking status, BMI, regular exercise, regular sports, sleeping time, medical status, disease history, and functional capacity. Results: For men without critical diseases, mortality risk declined linearly with increased walking time after adjustment for confounders (Ptrend = 0.018). Walking ≥2 hours/day was significantly associated with lower all-cause mortality (HR 0.49; 95% CI, 0.27–0.90). For men with critical diseases, walking 1–2 hours/day showed a protective effect on mortality compared with walking <0.5 hours/day after adjustment for confounders (HR 0.29; 95% CI, 0.06–1.20). Walking ≥2 hours/day showed no benefit on mortality in men with critical diseases, even after adjustment for confounders. Conclusions: Different duration of daily walking was associated with decreased mortality for younger-elderly men with or without critical diseases, independent of sociodemographic and lifestyle factors, BMI, medical status, disease history, and functional capacity. Incorporating regular walking into daily lives of younger-elderly men may improve longevity and successful aging.
Background: Many cross-sectional studies have examined the incidences of herpes zoster (HZ) and postherpetic neuralgia (PHN), but prospective studies in Japanese older adults are lacking. Therefore, we conducted a community-based prospective cohort study to determine the incidence in Japanese adults aged ≥50 years. Methods: We recruited 12 522 participants from Shozu County, Kagawa Prefecture, between December 2008 and November 2009 and followed participants for 3 years. When a subject presented with symptoms suggestive of HZ, they were examined at collaborating medical institutions and cooperated with onset and recovery surveys (eg, measurement of varicella zoster virus-specific immunity and a pain survey). The hazard ratios (HRs) of HZ and PHN according to sex and age were analyzed by Cox regression analysis with a significance level of 5%. Results: The incidence of HZ was 10.9/1000 person-years (men: 8.5/1000 person-years; women: 12.8/1000 person-years) and was significantly higher in women than in men (HR 1.5; 95% confidence interval, 1.2–1.8). The incidence of PHN was 2.1/1000 person-years (men: 1.7/1000 person-years; women: 2.4/1000 person-years), with no significant sex differences. A total of 19% of HZ cases progressed to PHN; no sex-specific difference in the proportion of PHN cases was observed. Conclusions: We clarified the accurate incidences of HZ and PHN in a population of Japanese older adults. These incidences increased with age. HZ incidence was higher in women than in men, while PHN incidence did not differ markedly between the sexes.
Background: Some infectious agents have been shown to be human carcinogens. The current study focused on estimation of cancer burden attributable to infection in different regions of Asia. Methods: By systematically reviewing previous studies of the infection prevalence data of 13 countries in Asia and relative risks of specific cancers, we calculated the population attributable fraction of carcinogenic infections. Using data from GLOBOCAN 2012, the overall country-specific and gender-specific number of new cancer cases and deaths resulting from infection were estimated. Results: Across 13 principal Asian countries, the average prevalence and range was 6.6% (0.5% in Japanese women to 15.0% in Vietnamese men) for hepatitis B virus (HBV), 2.6% (0.3% in Iran to 5.1% in Saudi Arabia) for hepatitis C virus (HCV), 7.9% (2.8% in Pakistan to 17.7% in China) for human papillomavirus (HPV), and 61.8% (12.8% in Indonesia to 91.7% in Bangladesh) for Helicobacter pylori (HP). The estimated total number of cancer cases and deaths caused by infection in these 13 countries were 1 212 026 (19.6% of all new cancer cases) and 908 549 (22.0% of all deaths from cancer). The fractions of cancer incidence attributable to infection were 19.7% and 19.5% in men and women, respectively. The percentages of cancer deaths attributable to infection were 21.9% and 22.1% in men and women, respectively. Among the main infectious agents, HP was responsible for 31.5% of infection-related cancer cases and 32.8% of infection-related cancer deaths, followed by HBV (28.6% of new cases and 23.8% of deaths), HPV (22.0% of new cases and 27.3% of deaths), and HCV (12.2% of new cases and 10.6% of deaths). Conclusions: Approximately one quarter of all cancer cases and deaths were infection-associated in Asia, which could be effectively prevented if appropriate long-term controls of infectious agents were applied.
Background: Cancer mortality is increasing with the aging of the population in Japan. Cancer information obtained through feasible methods is therefore becoming the basis for planning effective cancer control programs. There are three time-related factors affecting cancer mortality, of which the cohort effect is one. Past descriptive epidemiologic studies suggest that the cohort effect is not negligible in cancer mortality. Methods: In this paper, we develop a statistical method for automatically detecting a cohort effect and assessing its statistical significance for cancer mortality data using a varying coefficient model. Results: The proposed method was applied to liver and lung cancer mortality data on Japanese men for illustration. Our method detected significant positive or negative cohort effects. The relative risk was 1.54 for liver cancer mortality in the cohort born around 1934 and 0.83 for lung cancer in the cohort born around 1939. Conclusions: Cohort effects detected using the proposed method agree well with previous descriptive epidemiologic findings. In addition, the proposed method is expected to be sensitive enough to detect smaller, previously undetected birth cohort effects.
Background: This study aimed to evaluate the practical utility of respondent-driven sampling (RDS) among regular tobacco and alcohol users in Taipei, Taiwan. Methods: RDS was implemented from 2007 to 2010 to recruit seed individuals who were 18 to 50 years old, regular tobacco and alcohol users, and currently residing in Taipei. Each respondent was asked to refer up to five friends known to be regular tobacco smokers and alcohol drinkers to participate in the present study. Information pertaining to drug use was collected using an audio computer-assisted self-interview instrument. RDSAT software was used for data analyses. Results: The prevalence estimates of illegal-drug-using behaviors attained equilibrium after three to five recruitment waves. Nearly one-fifth of the participants had ever used illegal drugs, of whom over 60% were polydrug users. The RDS-adjusted prevalences of illegal-drug-using behaviors among early-onset smokers were all two or three times higher than those among late-onset smokers. Conclusions: Our results provided an empirical basis for the practicality and feasibility of using RDS to estimate illegal drug use prevalence among regular tobacco and alcohol users.
Background: The independent and combined associations of muscle strength and obesity on the prevalence of type 2 diabetes in Japanese men remain unclear. Methods: Hand grip strength was cross-sectionally evaluated between 2011 and 2013 to assess muscle strength in 5039 male workers aged 40 to 64 years. Weight and height were measured, and overweight/obesity was defined as a body mass index ≥25 kg/m2. The prevalence of type 2 diabetes, defined as fasting plasma glucose ≥126 mg/dL and/or hemoglobin A1c ≥6.5% and/or self-reported physician-diagnosed diabetes, was evaluated. Odds ratios (OR) and 95% confidence intervals (95% CI) for the prevalence of type 2 diabetes were obtained using a logistic regression model. Results: In total, 611 participants had type 2 diabetes, and 1763 participants were overweight/obese. After adjustment for covariates, we found an inverse association between muscle strength and the prevalence of type 2 diabetes (P for trend <0.01). In addition, when the analyses were stratified by obesity status, the multivariable-adjusted OR per 2-standard-deviation increase in muscle strength was 0.64 (95% CI, 0.49–0.83) in the overweight/obese group, compared to a weaker relationship in the normal-weight group (OR 0.79 per 2-standard-deviation increase; 95% CI, 0.60–1.06). Conclusions: Dynapenia, an age-related decrease in muscle strength, is associated with increased prevalence of type 2 diabetes, and this relationship is stronger in overweight/obese middle-aged Japanese men than in normal-weight men.