Japanese Legacy Cohorts: Six-Prefecture Cohort Study (Hirayama Cohort Study).

Late Dr Takeshi Hirayama and his colleagues conducted a mortality follow-up of a large-scale cohort in six prefectures in Japan. This study is called the six-prefecture cohort study or Hirayama Cohort Study. The study subjects were residents aged 40 years or older at the baseline survey in 1965, which covered 94.8% of residents identified in the study area by the National Census conducted on October 1, 1965. The mortality of 264,118 cohort members was followed until the end of 1982. One of the most important findings made by this study was an association between second-hand smoke exposure and lung cancer. This finding is the origin of the worldwide spread of smoking ban in indoor public venues and workplaces. Other major findings obtained from the study are also briefly described in this article.

Possible effect of maternal safe food preparation behavior on child malnutrition in Benin, Africa.

BACKGROUND: In many developing countries, faulty complementary feeding practises and frequently contaminated foods are contributing factors to child malnutrition. The aims of this study were to evaluate the nutrition status of, and clarify the maternal safe food preparation behaviors associated with malnutrition in, children aged <5 years in Cotonou, Benin. METHODS: This study targeted 300 mother-child pairs visiting the University Hospital of Mother and Child Cotonou Lagoon. Mothers were interviewed using a structured questionnaire. Child height/length and weight measurements were determined and Z-scores were calculated using the 2006 World Health Organization Child Growth Standards. Children with Z-score < -2 were considered to have stunting or be underweight. On logistic regression analysis, significant variables on bivariate analysis, the associations of which were clarified in previous studies, were established as independent variables. Approximately 80% of the children who participated in this study were aged < 1 year. Being underweight was analyzed as a dependent variable. RESULTS: Regarding nutrition status, 11.0% of the children had stunting and 14.7% were underweight. On logistic regression analysis, underweight was correlated significantly with birthweight. As a remarkable point, food refrigeration was statistically significant. Food refrigeration can possibly be regarded as a maternal safe food preparation behavior. CONCLUSIONS: Maternal safe food preparation behaviors can prevent child malnutrition, even after considering biological and socioeconomic factors.

Malnutrition among vaccinated children aged 0-5 years in Batouri, Republic of Cameroon.

Objectives: Malnutrition continues to contribute to a high infant mortality rate. This study aimed to determine the prevalence of malnutrition and its potential association with the time at which complementary feeding was introduced among children aged 0-5 years in Batouri, Republic of Cameroon. Methods: Mothers (n=212) were interviewed using a structured questionnaire. Child height or length, and weight measurements were determined and the appropriate Z-scores calculated. Multiple regression analysis was performed with the values of all nutritional status indicators as dependent variables and the time of commencing complementary feeding, and the child's age and sex, as independent variables. Results: The prevalence of stunting (height/length for age<-2 standard deviation [SD]), underweight (weight for age<-2SD), and wasting (weight for height/length<-2SD) was 45.8%, 30.2%, and 11.3%, respectively. Even taking into consideration the biological variables, there was a significant association in the effects of time of starting complementary foods on the nutritional status indicators. Furthermore, adding socio-economic variables did not produce a rise in adjusted R2 values for all age group models concerned. Conclusions: Approximately 30% of the children in the study region were underweight, and approximately half of the children exhibited stunting, indicating chronic malnutrition. Commencing complementary feeding at an appropriate time had a positive effect on nutritional status from approximately 2 years of age.

Sunlight exposure may be a risk factor of hearing impairment: a community-based study in Japanese older men and women.

BACKGROUND: Oxidative stress is an important factor in the pathology of age-related hearing loss. Recent animal studies have reported that ultraviolet radiation in sunlight is related to systemic induction of oxidative stress. Chronic sun exposure leads to photodamaged skin, which is manifested as facial skin wrinkling and hyperpigmentation. We hypothesized that sunlight exposure, as assessed by the severity of facial skin photodamage, might be associated with hearing impairment through an oxidative stress mechanism. To examine this, we performed a cross-sectional analysis by using the baseline data from a community-based cohort study of older Japanese. METHODS: A total of 805 residents (342 men and 463 women) aged 65 years or older living in Kurabuchi Town, Gunma prefecture, Japan, were examined between 2005 and 2006. Facial skin condition was quantified by image analysis of standardized facial images. Hearing impairment was defined as a failure to hear a 30-dB signal at 1 kHz and a 40-dB signal at 4 kHz in the better ear in pure-tone audiometric tests. RESULTS: In men, facial wrinkle was positively associated with hearing impairment (for highest vs lowest: multivariate-adjusted odds ratio, 2.16; 95% confidence interval, 1.00-4.66; p for trend = .01). Stratified analysis by age, educational level, smoking status, sunscreen or foundation use, and diabetes showed results similar to those for men as a whole. This association was particularly pronounced in men with the low levels of antioxidants and without occupational noise exposure. We observed no apparent association in women. CONCLUSIONS: The results support the hypothesis that chronic sun exposure is a risk factor of hearing impairment.

Lifestyle factors and visible skin aging in a population of Japanese elders.

BACKGROUND: The number of studies that use objective and quantitative methods to evaluate facial skin aging in elderly people is extremely limited, especially in Japan. Therefore, in this cross-sectional study we attempted to characterize the condition of facial skin (hyperpigmentation, pores, texture, and wrinkling) in Japanese adults aged 65 years or older by using objective and quantitative imaging methods. In addition, we aimed to identify lifestyle factors significantly associated with these visible signs of aging. METHODS: The study subjects were 802 community-dwelling Japanese men and women aged at least 65 years and living in the town of Kurabuchi (Takasaki City, Gunma Prefecture, Japan), a mountain community with a population of approximately 4800. The facial skin condition of subjects was assessed quantitatively using a standardized facial imaging system and subsequent computer image analysis. Lifestyle information was collected using a structured questionnaire. The association between skin condition and lifestyle factors was examined using multivariable regression analysis. RESULTS: Among women, the mean values for facial texture, hyperpigmentation, and pores were generally lower than those among age-matched men. There was no significant difference between sexes in the severity of facial wrinkling. Older age was associated with worse skin condition among women only. After adjusting for age, smoking status and topical sun protection were significantly associated with skin condition among both men and women. CONCLUSIONS: Our study revealed significant differences between sexes in the severity of hyperpigmentation, texture, and pores, but not wrinkling. Smoking status and topical sun protection were significantly associated with signs of visible skin aging in this study population.

[Pathological and biochemical studies of 30 Niigata autopsy cases related to Minamata disease].

OBJECTIVES: To reevaluate pathologically and biochemically 30 autopsy cases related to Minamata disease (MD) in Niigata Prefecture (NP) and compare the findings with those of autopsy cases related to MD in Kumamoto Prefecture (KP). METHODS: Recently, a set of pathological materials of these 30 autopsy cases has been sent from the Brain Research Institute at the University of Niigata to the National Institute for Minamata Disease (NIMD). The materials from each autopsy case were reexamined at the NIMD. RESULTS: There were no postnatal and fetal cases of MD in the NP autopsy materials. The contents of total mercury (T-Hg), methylmercury (Me-Hg), inorganic mercury (I-Hg) and selenium were measured in the organs of cerebrum, cerebellum, liver and kidney. The contents of T-Hg, Me-Hg and I-Hg were much higher in two cases than in controls. The pathological findings leading to the diagnosis of MD in the NP cases were essentially the same as those in KP, including the peripheral nerve lesions. In the most severely affected case of MD in NP, formation of multiple vacuoles of various sizes was observed in the cerebellar cortex, which was never encountered in the KP cases. The KP lesions were similar to that observed in an acute case of Me-Hg-treated common marmoset studied in the NIMD. CONCLUSION: The pathological features were essentially the same between the adult cases of MD in NP and KP.

[Critical thinking on "home visits" through the case method using the teaching material, "the twelfth child birth"].

OBJECTIVE: To use case method seminars in order to critically assess "home visits" for public health nursing practice. METHOD: "The twelfth childbirth" was developed for use as material for the case method in 2002. This case story involves the dilemma of a public health nurse as to whether or not she should intervene in the "private affairs" of a married couple. Case teaching was performed in two seminars during the period from July 2002 to February 2003. Participants in the first seminar were 18 health professionals (13 public health nurses and five supervisors) in Japan, and nine health professionals (8 midwives and one physician) from Cambodia took part in the second. RESULTS: For the problems from the case, the participants in the two seminars made their decisions analytically. Decision making was informative and took different directions. The public health nurses in Japan advocated a collaborative intervention with other health professionals. On the other hand, the midwives from Cambodia selected an approach involving heavy commitments to family planning undertaken by individual midwives. From the discussion in the seminars, this case story was satisfied through the following: (1) the participants used the information in the case to address the problem; (2) the participants thought analytically in order to evaluate potential solutions; and (3) the participants had sufficient information for analysis in the case. CONCLUSION: Both seminars provided good opportunities to enhance critical thinking on "home visits" as a tool for intervention and to develop thinking skills needed for public health nursing practice.

Surgery plus chemotherapy compared with surgery alone for localized squamous cell carcinoma of the thoracic esophagus: a Japan Clinical Oncology Group Study--JCOG9204.

PURPOSE: We performed a multicenter randomized controlled trial to determine whether postoperative adjuvant chemotherapy improves outcome in patients with esophageal squamous cell carcinoma undergoing radical surgery. PATIENTS AND METHODS: Patients undergoing transthoracic esophagectomy with lymphadenectomy between July 1992 and January 1997 at 17 institutions were randomly assigned to receive surgery alone or surgery plus chemotherapy including two courses of cisplatin (80 mg/m2 of body-surface area x 1 day) and fluorouracil (800 mg/m2 x 5 days) within 2 months after surgery. Adaptive stratification factors were institution and lymph node status (pN0 versus pN1). The primary end point was disease-free survival. RESULTS: Of the 242 patients, 122 were assigned to surgery alone, and 120 to surgery plus chemotherapy. In the surgery plus chemotherapy group, 91 patients (75%) received both full courses of chemotherapy; grade 3 or 4 hematologic or nonhematologic toxicities were limited. The 5-year disease-free survival rate was 45% with surgery alone, and 55% with surgery plus chemotherapy (one-sided log-rank, P =.037). The 5-year overall survival rate was 52% and 61%, respectively (P =.13). Risk reduction by postoperative chemotherapy was remarkable in the subgroup with lymph node metastasis. CONCLUSION: Postoperative adjuvant chemotherapy with cisplatin and fluorouracil is better able to prevent relapse in patients with esophageal cancer than surgery alone.