Subsite-specific trends in mid- and long-term survival for head and neck cancer patients in Japan: A population-based study

Advances in diagnostic techniques and treatment modalities have impacted head and neck cancer (HNC) prognosis, but their effects on subsite-specific prognosis remain unclear. This study aimed to assess subsite-specific trends in mid- and long-term survival for HNC patients diagnosed from 1993 to 2011 using data from population-based cancer registries in Japan. We estimated the net survival (NS) for HNC by subsite using data from 13 prefectural population-based cancer registries in Japan. Changes in survival over time were assessed by multivariate excess hazard model of mortality. In total, 68,312 HNC patients were included in this analysis. We observed an overall improvement in 5-year NS for HNC patients in Japan. However, survival varied among subsites of HNC, with some, such as naso-, oro- and hypopharyngeal cancers, showing significant improvement in both 5- and 10-year NS, whereas others such as laryngeal cancer showed only a slight improvement in 5-year NS and no significant change in 10-year NS after adjustment for age, sex and stage. In conclusion, the study provides insights into changing HNC survival by site at the population level in Japan. Although advances in diagnostic techniques and treatment modalities have improved survival, these improvements are not shared equally among subsites.

[Report on COVID-19 infection prevention and control training sessions for care homes provided by Kawaguchi city and comparison with those provided by the local governments in Japan]

Objectives　We compared COVID-19 prevention and control information provided to care homes (CHs) by the Kawaguchi City public health center (PHC), which utilizes our precedent advice on nfection, with the information from several local governments (LGs) in Japan. This study aimed to highlight the role of LG-associated doctors in providing information to CHs, utilizing their precedent advice on infection control in CHs and medical facilities. This study analyzed the sector and type of information the LGs should provide to CHs to prevent and control COVID-19.Methods　We compared training sessions on COVID-19 prevention and control information provided to CHs by the Kawaguchi City PHC with training sessions offered by several other LGs in Japan that are available on their websites.Results　The Kawaguchi City PHC has been providing COVID-19 information to CHs when needed, including prevention and control information, through their doctors, utilizing our precedent advice on infection control, management of health conditions of staff and residents, and early detection of COVID-19. In contrast, 68 LGs announced that they have provided training sessions to CHs for the prevention and control of COVID-19 through their official homepages from March to September 2022. These training sessions involved information dissemination by infection control specialist nurses (42.6%), clinic or hospital doctors (32.4%), infection control specialist doctors (11.8%), and staff from LG headquarters, PHC, or LG-associated doctors (51.5%). Among the 68 LGs, 41 provided information that included hand hygiene (95.1%), personal protective equipment (92.7%), proper ventilation (51.2%), and management of staff (90.2%) and resident (58.5%) health conditions. Furthermore, Kawaguchi City PHC and several LGs provided information for the early detection of COVID-19.Conclusion　We suggest that LGs provide COVID-19 training sessions conducted by LG doctors that include management of staff and resident health conditions, provision of early detection information, and utilization of precedent advice on infection in CHs and medical facilities.

[Impact of COVID-19 on cancer treatment: Results from 18 hospital-based cancer registries in Tochigi prefecture]

Objectives　To show the impact of COVID-19 on cancer treatment in Tochigi prefecture.Methods　The number of cancer cases registered in Tochigi prefecture before (2019) and after (2020) COVID-19 was compared using cancer registry data from 18 member hospitals of the Tochigi Prefecture Cancer Care Collaboration Council. Data were compared by sex, age, patient's address at the time of diagnosis, month of diagnosis, cancer site, cancer stage, and treatment. Data on screenings for stomach, colorectum, lung, female breast, cervix, and prostate cancers were investigated in detail.Results　The total number of registered cancer cases was 19,748 in 2019 and 18,912 in 2020 (a decrease of 836 cases [-4.2%]). Among the total cases, there were 11,223 and 10,511 males in 2019 and 2020, respectively (a decrease of 712 cases [-6.3%]) and 8,525 and 8,401 females in 2019 and 2020, respectively (a decrease of 124 cases [-1.5%]). The decrease was greater among males than among females. There was no decrease in the number of registered patients aged <40 years between 2019 and 2020. Based on the patients' address at the time of diagnosis, there was no decrease in the number of cases from outside of the Tochigi prefecture. Regarding the month of diagnosis, there was a notable decrease in the number of registered patients in May and August of 2020. Among the decrease of 836 cases detected by screening, 689(82.4%) were cases of stomach, lung, colorectum, female breast, cervix, and prostate cancer. The number of registered cases of malignant lymphoma, leukemia, and cancer of the oral cavity and pharynx, pancreas, bone and soft tissue, corpus uteri, and bladder did not decrease between 2019 and 2020. In terms of stage of cancer, the number of registered cases of carcinoma in situ, localized cancer, and regional lymph node metastases was lower in 2020 than in 2019, but there was no decrease in the number of registered cases of distant metastases or regional extension.Conclusion　The number of cancer cases registered in 2020 was lower than in 2019, and the degree of change varied by age, hospital, site, whether the case was detected by screening, and stage of cancer. In particular, a marked decrease was observed in the number of cases detected by screening. Furthermore, the decrease in the number of cancer cases registered in May and August of 2020 were believed to be due to the peak in the spread of COVID-19 and the associated declaration of a state of emergency.

Global survival trends for brain tumors, by histology: analysis of individual records for 556,237 adults diagnosed in 59 countries during 2000-2014 (CONCORD-3)

BACKGROUND

Survival is a key metric of the effectiveness of a health system in managing cancer. We set out to provide a comprehensive examination of worldwide variation and trends in survival from brain tumors in adults, by histology.

METHODS

We analyzed individual data for adults (15-99 years) diagnosed with a brain tumor (ICD-O-3 topography code C71) during 2000-2014, regardless of tumor behavior. Data underwent a 3-phase quality control as part of CONCORD-3. We estimated net survival for 11 histology groups, using the unbiased nonparametric Pohar Perme estimator.

RESULTS

The study included 556,237 adults. In 2010-2014, the global range in age-standardized 5-year net survival for the most common sub-types was broad: in the range 20%-38% for diffuse and anaplastic astrocytoma, from 4% to 17% for glioblastoma, and between 32% and 69% for oligodendroglioma. For patients with glioblastoma, the largest gains in survival occurred between 2000-2004 and 2005-2009. These improvements were more noticeable among adults diagnosed aged 40-70 years than among younger adults.

CONCLUSIONS

To the best of our knowledge, this study provides the largest account to date of global trends in population-based survival for brain tumors by histology in adults. We have highlighted remarkable gains in 5-year survival from glioblastoma since 2005, providing large-scale empirical evidence on the uptake of chemoradiation at population level. Worldwide, survival improvements have been extensive, but some countries still lag behind. Our findings may help clinicians involved in national and international tumor pathway boards to promote initiatives aimed at more extensive implementation of clinical guidelines.

Recent Increasing Incidence of Early-Stage Cervical Cancers of the Squamous Cell Carcinoma Subtype among Young Women

Few studies have reported on the increase in cervical cancer incidence in Japan. We aimed to determine the relevant trends in the metropolitan regions of Japan and to identify the population with the highest risk, based on histological subtype, cancer stage, and diagnostic processes. Using population-based data (2009–2013), we identified 2110 women, aged ≥20 years, with cervical cancer. We estimated the age-standardized and age-specific incidence rates of cervical cancer for the study period based on the 1985 national model population. The average annual percent change (AAPC) and 95% confidence interval (CI) were calculated using the joinpoint regression analysis. We stratified the analyses based on histological subtypes, stage, and diagnostic process via cancer screening. The increase in the overall age-standardized incidence was not significant. However, the increase was significant for women aged 30–39 years (AAPC 20.0%/year, 95% CI: 9.9–31.1), which was attributable to the increase in the incidence of the squamous cell carcinoma (SCC) subtype (AAPC 23.1%/year, 95% CI: 10.7–36.8). Among younger women, aged <50 years, further stratification showed an increase in the undiagnosed early-stage SCC subtype via cancer screening. In Japan, the incidence of HPV-related cervical cancer has been increasing in undiagnosed younger women.

Impact of D3 lymph node dissection on survival for patients with T3 and T4 colon cancer

PURPOSE

The clinical significance of D3 lymph node dissection for patients with colon cancer remains controversial. This study aims to clarify the impact of D3 lymph node dissection on survival in patients with colon cancer.

METHODS

This is a retrospective cohort study from a prospectively registered multi-institutional database of colorectal cancer in Japan. Propensity score matching method was applied to balance potential confounders of the treatment. A cohort of 10,098 patients who underwent radical colectomy for pT3 and pT4 colon cancer between 1985 and 1994 were identified. A total of 3,425 propensity score matched pairs were extracted from the entire cohort. The primary outcome measure was overall survival (OS).

RESULTS

In the entire cohort, there was a statistically significant difference in overall survival (OS) between the patients who had D3 and D2 lymph node dissection (p = 0.00003). The estimated hazard ratio (HR) for OS of patients who had D3 versus D2 lymph node dissection was 0.827 (95 % confidence interval, 0.757 to 0.904). In the matched cohort, there was also a significant difference in OS between the two groups (p = 0.0001), and the estimated HR for OS was 0.814 (95 % confidence interval, 0.734 to 0.904).

CONCLUSIONS

We found D3 lymph node dissection for pT3 and pT4 colon cancer to be associated with a significant survival advantage in a large-scale database, even after adjusting potential confounders of lymph node dissection. This finding may provide a rationale for D3 lymph node dissection in radical surgery for pT3 and pT4 colon cancer.

Proposal of new nodal classifications for non-small-cell lung cancer based on the number and ratio of metastatic lymph nodes

OBJECTIVE

The study aimed to evaluate the effectiveness of two new nodal classifications based on the number of metastatic lymph nodes (LNs) or ratio of metastatic to examined LNs (LNR) in making a prognosis, compared with the current nodal classification based on the location of metastatic LNs.

METHODS

We analyzed 651 non-small-cell lung cancer patients who had undergone complete resection with the removal of more than five LNs between 1986 and 2003, excluding preoperative treatment cases, and a Tis, T4, N3, and M1 status, along with limited resection and operative death cases. The cutoff numbers for each category in the two new nodal classifications (number of metastatic LNs (nN0-2): 0, 1-2, and >3, and LNR (rN0-2): 0, 1-12, and >12%) were defined so that the numbers corresponded with paired categories within the current nodal classification.

RESULTS

The 5-year survival rate was 75.4% for patients with the N0 categories in all three classifications. The 5-year survival rates for patients with N1 and N2 categories were 52.2% and 42.6% according to the current nodal classification, 54.3% and 39.8% according to the number of metastatic LNs, and 58.8% and 35.0% according to the LNR, respectively. Although all three nodal classifications were independent prognostic factors along with the age and pathological T status, when the three nodal classifications were entered into multivariate analysis individually, the hazard ratio of rN2 was the highest, at 3.15, followed by that of nN2 at 2.96.

CONCLUSIONS

The LNR followed by the number of metastatic LNs may be more effective prognostic indicators than the current nodal classification based on the location of metastatic LNs. For the future revision, the number of metastatic LNs and LNR should be evaluated as indicators for the nodal classification of lung cancer.

Six principal symptoms and coronary artery sequelae in Kawasaki disease

BACKGROUND

The relationship between coronary artery sequelae due to Kawasaki disease and the six principal symptoms associated with the latter are still unknown.

METHODS

Among the 16,952 patients reported in the 17th nationwide survey on Kawasaki disease, 14,068 were found to have definite and typical cases with five or six principal symptoms. The proportions of coronary artery aneurysms including dilatation of the artery were compared between the patient group with six symptoms and that with five.

RESULTS

Percentages for those with all six symptoms (7223) were 4.7% for coronary dilatations (i.e. small aneurysms), 1.7% for coronary aneurysms (i.e. middle-sized aneurysms), and 0.42% for giant coronary aneurysms (i.e. large aneurysms) 1 month after onset, whereas for those with five symptoms (6,845), the corresponding percentages were 4.1%, 1.4%, and 0.22%, respectively. For overall observation, the odds ratios were 1.44, 1.28, and 1.70 for the three types of aneurysm, respectively. For male patients, all the odds ratios were >1.0, and some were significant. In contrast, odds ratios <1.0 were observed among those with six symptoms in some subgroups among female patients despite the lack of significance.

CONCLUSIONS

Because odds ratios were elevated - especially for male patients with Kawasaki disease - with all six principal symptoms, patients with the six symptoms are more problematic for coronary sequelae among the definite cases, although there was not a specific symptom for the sequelae.

Monthly observation of the number of patients with Kawasaki disease and its incidence rates in Japan: chronological and geographical observation from nationwide surveys

Background

Although the epidemiologic features of Kawasaki disease for Japan have been observed, recently, chronological and geographical observations of the number of patients and incidence rate of the disease have not been conducted using observation units smaller than the whole country.

Methods

We used the recent 5 nationwide surveys (the 15th to 19th) of Kawasaki disease in Japan, which covered patients for 10 years, i.e., between 1997 and 2006. The monthly number of patients by prefecture was calculated, and the number was corrected by the response rate of the target institutes of the prefecture. Chronological changes in the number of patients were observed by district. Geographical changes in the incidence rates were observed bimonthly by prefecture for the recent 6 years, from 2001 through 2006.

Results

On the whole, the monthly number of patients increased gradually. For each year, the number was the highest in January and the lowest in October; it was relatively high during summer as well. Some differences existed among the districts with regard to the monthly observations. Bimonthly observations of the incidence rate by prefecture revealed the differences in the characteristics of the epidemics in different geographic areas.

Conclusion

The chronological and geographical changes in the occurrence of Kawasaki disease in Japan for the recent 10 years suggested the involvement of one or more infectious agents in the occurrence of the disease.

Epidemiologic features of Kawasaki disease in Japan: results from the nationwide survey in 2005-2006

BACKGROUND

The most recent epidemiologic features of Kawasaki disease are unknown.

METHODS

The 19th nationwide survey of the disease was conducted in 2007, targeting patients who were affected by this disease in 2005 and 2006. All pediatric departments in hospitals with 100 or more beds and pediatric hospitals were asked to report all Kawasaki disease patients during the 2 survey years.

RESULTS

From 1543 departments and hospitals, a total of 20475 patients (10041 in 2005 and 10434 in 2006) were reported. There were 11892 male patients and 8583 female patients. The average annual incidence rate was 184.6 per 100000 children aged 0-4 years. The number of patients and the incidence rate have increased significantly during the past 12 years. The age-specific incidence rate was distributed monomodally with a peak at 6-8 months of age. The prevalence of cardiac lesions in the acute phase of the disease and of cardiac sequelae were higher among infants and old patients.

CONCLUSION

The number of patients with Kawasaki disease and its incidence rate in Japan are continuously increasing.

Relationship between BMI and all-cause mortality in Japan: NIPPON DATA80

As body composition in Asian populations is largely different from Western populations, a healthy BMI could also differ between the two populations. Thus, further study is needed to determine whether a healthy BMI in Asians should be lower than Western populations, as recommended by the World Health Organization (WHO). We investigated the relationship between BMI and mortality in a sample of 8,924 Japanese men and women without stroke or heart disease. During 19 years of follow-up, 1,718 deaths were observed. We found a U-shaped relationship between BMI and fatal events. Risk of total mortality was highest in participants with BMI <18.5 kg/m(2) and lowest in participants with BMI 23.0-24.9 kg/m(2). These findings persisted even after excluding the first 5 years of follow-up with a focus on healthy participants who never smoked, were aged <70 years, and had total cholesterol (TC) levels >or=4.1 mmol/l (N=3712). For both the full sample and healthy participants, all-cause mortality risk did not differ between BMI ranges 21.0-22.9 and 23.0-24.9 kg/m(2). Our findings do not support the recent WHO implications that BMIs <23.0 kg/m(2) is healthy for Asians. Therefore, further studies are needed to identify an optimal BMI range for Asia.

Increasing incidence of Kawasaki disease in Japan: nationwide survey

BACKGROUND

The last nationwide survey of Kawasaki disease in Japan was conducted in 2003; the epidemiologic features of the disease in Japan since then are unknown.

METHODS

All the hospitals with a pediatric department and a bed capacity of > or =100, or hospitals having a bed capacity of <100 but specializing in pediatrics in Japan were asked to report (by mail) all patients with Kawasaki disease who visited the hospital due to the disease in 2003 and 2004.

RESULTS

Of the 2335 hospitals asked to participate, 1058 reported 19,138 patients with Kawasaki disease during the 2 year period 2003-2004. The annual incidence in 2004 reached 174.0 per 100,000 children under 5 years of age. The yearly number of patients and annual incidence increased significantly after the last nationwide epidemic of the disease in 1986. The number of patients was largest in January and lowest in October. The age-specific incidence was highest for those aged 9-11 months, and 88.9% of the patients were under 5 years of age. Of the reported patients, 2595 (13.6%) had cardiac lesions in the acute phase of the disease and 844 (4.4%) had cardiac sequelae 1 month after the onset of the disease.

CONCLUSION

The number of patients and the incidence of Kawasaki disease in Japan has increased year by year in the last two decades.

Mortality among persons with a history of kawasaki disease in Japan: mortality among males with cardiac sequelae is significantly higher than that of the general population

BACKGROUND

The long-term prognosis of those having a history of Kawasaki disease (KD) is still unknown.

METHODS AND RESULTS

Between July 1982 and December 1992, 52 collaborating hospitals collected data on all patients having a new definite diagnosis of KD. Patients were followed-up until December 31, 2004 or their death. Standardized mortality ratios (SMRs) were calculated based on the Japanese vital statistics data. Of 6,576 patients enrolled, 36 (27 males, 9 females) died and the SMR was 1.14. Despite the high SMRs during the acute phase, the mortality rate was not high after the acute phase for the entire group of patients. Although the SMR after the acute phase was 0.71 for those without cardiac sequelae, 10 males (but none of the females) with cardiac sequelae died during the observation period; and the SMR for the male group with cardiac sequelae was 2.55 (95% confidence interval: 1.23-4.70).

CONCLUSIONS

The mortality rate among males with cardiac sequelae because of KD was significantly higher in this cohort than in the general population. On the other hand, those for females with the sequelae and for both males and females without sequelae were not elevated.

Re-treatment regimens for acute stage of Kawasaki disease patients who failed to respond to initial intravenous immunoglobulin therapy: analysis from the 17th nationwide survey

BACKGROUND

Current regimens for re-treatment of patients with Kawasaki disease who failed to respond to the initial intravenous immunoglobulin (IVIG) therapy are still uncertain. The purpose of this study is to reveal what regimens were used as the initial therapy and re-treatment for acute stage of Kawasaki disease in the current Japanese medical setting.

METHODS

The 17th nationwide survey on Kawasaki disease covered patients whose onset was in 2001 and 2002. In questionnaires sent to all hospitals with a bed capacity of 100 or more and a pediatric department, several questions related to therapeutic regimens for Kawasaki disease were posed. The authors observed the proportions of hospitals that had regimens for patients who failed to respond to the initial therapy.

RESULTS

Among those hospitals that responded to the survey, 1052 (64.1%) reported that at least one patient with Kawasaki disease visited the hospital. Among these 1052 hospitals, 73.3% had a regimen to administer 30-39 mg/kg per day of oral aspirin with initial IVIG. The proportion of hospitals that used 1 g/kg per day of IVIG for 2 days was the largest among the options for the initial treatment. For those patients who fail to respond to the initial therapy, 464 hospitals (44.1%) reported that their pediatricians would use additional IVIG only. The number of hospitals that planned to administer high-dose IVIG and ulinastatin was 185 (17.6%). The number of hospitals having regimens of additional IVIG and steroids was 54 (5.1%).

CONCLUSIONS

The current status of the treatment for patients with Kawasaki disease not responding to the initial IVIG therapy in Japan was revealed. A randomized trial of a large sample is needed to ascertain the effectiveness of several options for re-treating Kawasaki disease.

Impact of the universal hepatitis B immunization program in Mongolia: achievements and challenges

BACKGROUND

The impact of the universal infant hepatitis B (HB) immunization program initiated in 1991 in Mongolia is still unclear.

METHODS

A nationwide school-based cross-sectional serosurvey was conducted in 2004, with stratified, multistage, random cluster sampling from all public elementary schools (n=593) in Mongolia. All children were tested for serological markers of hepatitis B virus (HBV).

RESULTS

Serology results were available for 1,145 children (592 boys and 553 girls) aged 7-12 years (survey response rate: 93%). Immunization card was available for 702 (61.3%) children. The coverage of complete HB vaccination was 60.1% and it was increased by birth cohort from 44% to 76%. Significantly higher proportion of children in Metropolitan cities (75.2%) was completely vaccinated with HB compared to those in Province centers (55.7%) and rural areas (59.1%). HBV infection occurred in 5.9%, 13.2%, and 20.8% of complete vaccinees living in Metropolitan, Province centers, and rural areas, respectively; of whom 1.2%, 2.9%, and 8.6% were HB surface antigen (HBsAg) carriers, respectively. Only 17.0% of the children had protective anti-HBs which decreased from 31.1% to 16.3% among 7 to 12-year-olds indicating its decay with time.

CONCLUSIONS

Prevalence of HBV infection and carriage among young generation meaningfully declined compared with those of previous studies in Mongolia. The coverage of birth dose and complete HB vaccination was significantly low in Province centers and rural areas which should be taken into consideration.

Administration of hepatitis B vaccine in winter as a significant predictor of the poor effectiveness of vaccination in rural Mongolia: evidence from a nationwide survey

BACKGROUND

Universal hepatitis B (HB) immunisation is the most effective means for prevention of hepatitis B virus (HBV) infection worldwide. Maintaining the vaccine cold chain is an essential part of a successful immunisation programme. Our recent nationwide survey in Mongolia has observed significant urban-rural differences in the prevalence of HBV infection among vaccinated cohorts.

OBJECTIVE

To examine whether the administration of HB vaccine in winter contributes to these residential discrepancies on the effectiveness of vaccination.

DESIGN AND SETTING

In 2004, a nationwide serosurvey was carried out covering both urban and rural areas of Mongolia. Sampling was multistage, with random probability from all public schools in the country.

PARTICIPANTS

A random sample of 1145 children (51.7% boys; aged 7-12 years), representative of Mongolian elementary school children.

RESULTS

Multivariate logistic regression analysis identified that total (past and current) HBV infection (OR 2.31, 95% CI 1.20 to 4.42; p = 0.012) was independently associated with the administration of all HB vaccines in winter. An increased OR for current HBV infection was also observed (OR 2.58, 95% CI 0.87 to 7.68; p = 0.089), but without significance. Interestingly, after stratifying by residence, the association between winter vaccination and total HBV infection was evident for rural (p = 0.008) but not for urban areas (p = 0.294). The frequency of vaccine-induced immunity was significantly (p = 0.007) lower for those who received HB vaccine at birth during winter in rural areas.

CONCLUSION

Administration of HB vaccine during winter is an important predictor of the low effectiveness of vaccination in rural Mongolia. To improve the effectiveness of HB vaccination in remote areas, cold chain control should be addressed with particular attention to the winter season.

Seroepidemiology of hepatitis B virus infection among children in Mongolia: results of a nationwide survey

BACKGROUND

Because Mongolia is one of the highly endemic countries for hepatitis B virus (HBV) infection in the world, hepatitis B (HB) vaccine was introduced into the National Expanded Program on Immunization in 1991. However, relatively few data are available concerning HBV infection among children born after the start of the program, so far. The aim of the present paper was to describe the seroepidemiology of HBV infection among primary school children using representative national data.

METHODS

In 2004, a nationwide school-based cross-sectional serosurvey was carried out throughout Mongolia, covering both urban and rural areas. Serum samples were tested for hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti-HBc) and hepatitis B e antigen (HBeAg) as well as for liver enzymes.

RESULTS

A total of 1145 children aged 7-12 years were studied, which represents nearly 2% of the second grade population of elementary schools in Mongolia. The overall prevalence of HBsAg and anti-HBc was 5.2% (95% confidence interval [CI]: 3.9-6.5%) and 15.6% (95%CI: 13.5-17.7%), respectively. Among HBsAg-positive children 67.8% (95%CI: 55.9-79.7%) were also positive for HBeAg. The prevalence of chronic HBV infection increased by age and was significantly higher among children from rural areas compared to those from urban areas (7.7% vs 3.0%; P < 0.001). In the multivariate logistic regression analysis, rural residence (odds ratio [OR]: 2.57; 95%CI: 1.45-4.58), male sex (OR: 1.9; 95%CI: 1.08-3.26) and age (OR: 1.5; 95%CI: 1.10-2.05) were independent demographic predictors for chronic HBV infection.

CONCLUSIONS

The prevalence of chronic HBV infection has been decreasing in the Mongolian young generation, most likely due to infant HB vaccination. However, significant rural-urban differences in the prevalence of HBV infection were found that demand further investigation to estimate the potential causes.

Analysis of hepatitis B surface antigen mutations in Mongolia: molecular epidemiology and implications for mass vaccination

Although the potential significance of hepatitis B surface antigen (HBsAg) mutants for failure of immunization has been studied in some endemic countries, whether the "a" determinant variants are responsible for vaccine failure in Mongolia remains unknown. Fifty-nine HBsAg-positive children (age: 8.8 +/- 0.9 years) who had been observed during the nationwide survey of vaccinated cohorts conducted in 2004 were subjected to molecular analyses of hepatitis B virus (HBV). Partial S gene sequences encoding amino acids (aa) 40-171 of HBsAg were determined in 57 children (96.6%) who had detectable HBV DNA. Phylogenetic analysis of the S gene sequences revealed that genotype D accounted for 93.0% and genotype A for 5.3%. Only one child (1.7%) had HBVs of genotypes A and D. HBsAg mutations were found in 17 (29.8%) children ranging from 1 to 4 aa per subject (mean +/- SD, 1.6 +/- 0.9 aa). Pro127Thr and Thr118Ala were the most common substitutions, which occurred in 6 (10.5%) and 3 (5.3%) subjects, respectively; none had Gly145Arg. There were no significant associations in the prevalence of HBsAg mutations with age, sex, residential area, or vaccination status against hepatitis B. Analysis of the deduced amino acid sequence of the entire preS1/preS2/S gene revealed that eight genotype D isolates and one genotype A isolate were quite similar to previously-reported wild-type isolates, suggesting that they are essentially wild-type, but not vaccine-induced mutants. In conclusion, the results demonstrate that hepatitis B surface gene mutants do not play a significant role in vaccination failure in Mongolia.

Body Mass Index and Risk of Stroke Mortality among a Random Sample of Japanese Adults: 19-Year Follow-Up of NIPPON DATA80

BACKGROUND

The relationship between body mass index (BMI) and stroke mortality remains unclear. The aim of the present study was to elucidate the relationship between BMI and stroke death in a representative cohort of Japanese men and women.

METHODS

We analyzed a database of 9,526 men and women aged 30 years and older who were randomly selected throughout Japan in 1980. These individuals had no history of stroke and were followed for 19 years. Hazard ratios (HR) and their 95% confidence intervals (CI) of deaths due to total stroke, cerebral infarction, and intracerebral hemorrhage were examined using Cox's proportional hazards regression models of BMI levels.

RESULTS

A U-shaped association between BMI and cerebral infarction mortality was observed. Participants with the highest BMI category (BMI > or = 30.0) showed a significantly highest HR for cerebral infarction (HR 2.46, 95% CI 1.01-5.99). The excess risk at the lower extreme of the BMI was confined to men. These associations did not change after excluding deaths occurring in the first 2 years of follow-up.

CONCLUSIONS

In the Japanese general population, a U-shaped association between BMI and cerebral infarction mortality was found and the excess risk at the lower extreme of the BMI was confined to men.

Hepatitis delta virus infection in mongolia: analyses of geographic distribution, risk factors, and disease severity

The prevalence and risk factors for hepatitis delta virus (HDV) infection among Mongolian school children were assessed by detecting the antibody against HDV and HDV RNA, and through structured interviews. The study subjects consisted of 181 children with the past or ongoing hepatitis B virus infection who were investigated during the nationwide serosurvey conducted in 2004. The prevalence of antibody to HDV was 6.1%, with the proportion of 13.6% among hepatitis B surface antigen (HBsAg)-positive subjects, all of whom had HDV RNA. Multivariate logistic regression analyses showed that injections (> 11 times) (odds ratio [OR] = 8.31, 95% confidence interval [CI] = 1.28-54.07) and blood sampling (> 3 times) (OR = 5.34, 95% CI = 1.12-25.53) in health care settings, hospitalization (> 3 times) (OR = 6.20, 95% CI = 1.18-32.71), and cohabitating with patients with chronic hepatitis (OR = 4.57, 95% CI = 1.26-16.55) predicted the seropositivity for antibody to HDV. These results suggest that parenteral exposures in health care settings and household transmission are the main routes of HDV transmission among Mongolian children.

Incidence of Kawasaki disease in Japan: the nationwide surveys of 1999-2002

BACKGROUND

The purpose of the present study was to describe the results of nationwide epidemiologic surveys of Kawasaki disease for the 4 year period 1999-2002.

METHODS

The design is a retrospective incidence survey. The patients reported in these two surveys are all new patients who were reported during the two study periods (1999-2000 and 2001-2002), although the data were collected retrospectively. A questionnaire was sent to all pediatric departments of hospitals with 100 beds or more throughout Japan, requesting data on patients with Kawasaki disease, such as sex, age, date of first hospital visit, recurrence, and cardiac lesions.

RESULTS

The total number of patients reported in the 4 year period 1999-2002 was 32 266 (18 604 male, 13 662 female), with an average annual incidence of 137.7 per 100 000 children younger than 5 years old. The male/female ratio was 1.30. The incidence peaked at 9-11 months of age, and the proportion of patients under 1 year of age was 26%. The monthly distribution had a high peak in January and a gradual increase in summer. Geographically, the high-incidence areas were limited to certain prefectures and moved from year to year. The cardiac lesions at acute stage and cardiac sequelae occurred more in children under 1 year and older than 4 years. Among the principal symptoms, fever persisting >or=5 days occurred most commonly, followed by conjunctival congestion, changes in lips and oral cavity, polymorphous exanthema, and changes of extremities. Cervical lymphadenopathy occurred less.

CONCLUSION

More than 32 000 patients with Kawasaki disease during the 4 year period 1999-2002 were reported to the nationwide incidence surveys. The number of patients is steadily increasing despite the decrease of children. The seasonal variation, geographical distribution, and age-specific distribution support the infection theory for the etiology of Kawasaki disease.

Congener profiles of PCDDs, PCDFs, and dioxin-like PCBs in the breast milk samples in Tokyo, Japan

Exposure to dioxins has raised much public concern recently. We determined the congeners' distribution of polychlorinated-dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in the breast milk samples collected in Tokyo, Japan. Breast milk was taken from 240 mothers, 30 days after delivery in 1999 and 2000 in Tokyo, Japan. The actual concentration and TEQ concentration of PCDDs (14 congeners), PCDFs (15 congeners), and dl-PCBs (12 congeners), and each congener's contribution to the total TEQ level were calculated. Among all the samples, PCDDs accounted for 34.8%, PCDFs accounted for 23.5%, dl-PCBs accounted for 41.7%, which was also similar in the breast milk from the primiparae and secundiparae. The main contributors to the total TEQ with increasing percentages were 2,3,4,7,8-PeCDF, 1,2,3,7,8-PeCDD and 3,3',4,4',5-PCB (#126), and they accounted for more than 65% of the total TEQ. Detailed congener analysis in breast milk samples is effective to understand dioxin sources.

Prevalence and risk factors for hepatitis C virus infection in Mongolian children: Findings from a nationwide survey

Although the hepatitis C virus (HCV) infection is one of the major causes of chronic hepatitis and hepatocellular carcinoma (HCC) in Mongolia, its prevalence among children and routes of transmission are largely unknown. The aim of the study was to determine the prevalence of anti-HCV antibodies and the possible risk factors for transmission among school children using representative national data. A nationwide cross-sectional survey among elementary school children was conducted in four main geographical regions and the metropolitan area of Mongolia, through multistage, stratified, random cluster sampling. Serum samples from 1,145 children (response rate, 93%; 592 boys and 553 girls; age range, 7-12 years), which represented nearly 2% of the second grade population in Mongolia, were tested for HCV antibodies with a third-generation immunoradiometric assay (IRMA). Positive samples were further evaluated by a third-generation immunoblot assay (RIBA). A standardized questionnaire concerning the socio-demographic characteristics and potential risk factors was used. Overall, seven subjects were confirmed to be anti-HCV seropositive, giving a prevalence of 0.6% (95% CI: 0.15-1.0%). The prevalence of anti-HCV increased with age. In the multivariate logistic regression analysis, adjusted for age, sex, and residence, the history of dental manipulation (odds ratio [OR] = 15.4; 95% CI: 1.4-164.8) and surgery (OR = 8.3; 95% CI: 1.5-45.6) were associated independently with the presence of anti-HCV. These findings suggest that contaminated equipment used in the dental and surgical manipulations probably played a predominant role in HCV transmission among Mongolian children. Strict guidelines on disinfection and sterilization procedures of medical instruments have to be introduced and should be followed to improve the control of HCV infection in Mongolia.

Correlation coefficients between the dioxin levels in mother's milk and the distances to the nearest waste incinerator which was the largest source of dioxins from each mother's place of residence in Tokyo, Japan

BACKGROUND

To observe the relationship between the PCDD/F and Co-PCB levels in samples of human breast milk and nearby waste incinerators in Tokyo, Japan.

METHODS

Breast milk was taken from 240 mothers residing in Tokyo, Japan to measure and analyze the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs; 14 congeners), polychlorinated dibenzofurans (PCDFs; 15 congeners), and coplanar polychlorinated biphenyls (Co-PCBs; 12 congeners) contained in the fat. Individual milk samples (about 50 ml) were obtained from the mothers 30 days after delivery, between the months of June and September in 1999 and 2000. A map of Tokyo was used to measure the distances between each mother's place of residence and the closest public and industrial waste incinerators.

RESULTS

The distances to the nearest waste incinerators bore no apparent correlations with the congeners of PCDD/Fs and Co-PCBs. The distances were also uncorrelated with the mean toxic equivalent quantities (TEQs) of PCDD/Fs (the sum of PCDDs and PCDFs), Co-PCBs, and the total PCDD/Fs and Co-PCBs.

CONCLUSIONS

Although waste incinerators were the largest source of dioxins in Japan at the time of the study, the dioxins levels of mother's milk bore no apparent relationships with the distances between the mothers' domiciles and the nearest waste incinerators. In this study, several meaningful factors were not taken into account, namely, the wind direction, the level of dioxin emitted from each incinerator, the level of environmental pollution of dioxins, and the average time the mothers stayed at home each day. A full understanding of these points awaits future studies.

Proteinuria is a prognostic marker for cardiovascular mortality: NIPPON DATA 80, 1980-1999

BACKGROUND: Proteinuria has been considered to be a prognostic marker for persons with diabetes mellitus, but only a limited number of studies about the relationship between proteinuria and mortality among general population has been available.

METHODS: The subjects were 10,897 individuals who participated in the National Cardiovascular Survey conducted in 1980 and who were aged 30 years or older living in 300 districts that had been randomly selected throughout Japan. The vital records were confirmed in 1999 and 7,203 subjects (3,180 males and 4,023 females) without a history of hypertension, stroke, heart disease, renal disease, or diabetes mellitus at the start of the study were investigated.

RESULTS: There were 126,825 person-years of follow-up. During the observed period of time, 371 died of cardiovascular causes, including 171 stroke deaths and 74 coronary deaths. The risk of proteinuria for cardiovascular mortality was greater than unity for those with a normal serum creatinine level, after adjusting for age and other cardiovascular disease risk factors.

CONCLUSIONS: When contrasted with other cardiovascular disease risk factors, urinary protein is an independent risk factor for cardiovascular death among the Japanese population.

Associations between dietary intake and breast milk dioxin levels in Tokyo, Japan

BACKGROUND

The presence of dioxins in breast milk has gained much attention recently. However, in Japan the relationship between the consumption of different foods and the human breast milk dioxin concentrations is still unclear.

METHODS

Breast milk was taken from 240 mothers residing in Tokyo, Japan to measure and analyze the concentrations of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and coplanar poly-chlorinated biphenyls contained in the fat. Individual milk samples were obtained from the mothers 30 days after delivery in 1999 and 2000. The data of the mothers' diets before pregnancy were collected by means of food frequency and amount estimation. Spearman correlation analysis and stepwise multiple linear regression were used to analyze the data.

RESULTS

The concentrations of dioxins in breast milk were influenced mainly by the mother's age and history of breast-feeding. All the Spearman correlation coefficients were less than 0.20. Pork, roast ham, sausage, salt codfish and tempura had negative correlations with breast milk dioxins.

CONCLUSIONS

History of breast-feeding and the mother's age should be considered and emphasized in this kind of analysis. The cause effect relationship between dietary intake and breast milk dioxin levels were still uncertain.

Relationship of PCDD/F and Co-PCB concentrations in breast milk with infant birthweights in Tokyo, Japan

OBJECTIVE

To observe how PCDD/F and Co-PCB concentrations in breast milk relate to infant birthweights in Tokyo, Japan.

STUDY DESIGN

Breast milk samples were collected from 240 mothers (aged 25-34years old) residing in Tokyo to measure the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs; 14 congeners), polychlorinated dibenzofurans (PCDFs; 15 congeners), and coplanar polychlorinated biphenyls (Co-PCBs; 12 congeners) in the breast milk fat. Individual milk samples (about 50ml) were obtained 30days after delivery, between the months of June and September in 1999 and 2000. The relationship of the infant birthweights with the PCDD/F and Co-PCB concentrations was observed.

RESULTS

The birthweights were negatively correlated the concentrations of many of the PCDD/F and Co-PCB congeners, with the mean toxic equivalent quantities (TEQs) of the Co-PCBs, and with the sum of the PCDD, PCDF and Co-PCBs, although their correlation coefficients were less than 0.200. Multiple regression analysis showed octachlorodioxin was statistically significant explanatory variate.

CONCLUSIONS

There were slight relationship between the dioxins levels of breast milk and the birthweights of the infants.

Mortality among persons with a history of Kawasaki disease in Japan: can paediatricians safely discontinue follow-up of children with a history of the disease but without cardiac sequelae?

AIM

To clarify the question of whether patients with Kawasaki disease suffer a higher mortality rate after the incidence of the disease in comparison with age-matched healthy individuals.

METHODS

Between July 1982 and December 1992, 52 collaborating hospitals collected data on all patients having a new, definite diagnosis of Kawasaki disease. Patients were followed up until 31 December 2001 or their death. The expected number of deaths was calculated from Japanese vital statistics data and compared with the observed number.

RESULTS

Of 6576 patients enrolled, 29 (20 males and 9 females) died. The standardized mortality ratio (SMR: the observed number of deaths divided by the expected number of deaths based on the vital statistics in Japan) was 1.15 (95% CI: 0.77-1.66). In spite of the high SMRs during the acute phase, the mortality rate was not high after the acute phase for the entire group of patients. Although the SMR after the acute phase was 0.75 for those without cardiac sequelae, six males (but none of the females) with cardiac sequelae died during this period; and the SMR for the male group with cardiac sequelae was 1.95 (95% CI: 0.71-4.25). The mortality from congenital anomalies of the circulatory system was elevated, but no increase in cancer deaths was observed.

CONCLUSION

Although it was not statistically significant, the mortality rate among males with cardiac sequelae due to Kawasaki disease appeared to be higher than in the general population. On the other hand, the mortality rates for females with the sequelae and both males and females without sequelae were not elevated.

Different effects of blood pressure on mortality from stroke subtypes depending on BMI levels: a 19-year cohort study in the Japanese general population—NIPPON DATA80

To evaluate the relationship between blood pressure and cerebrovascular death depending on body mass index (BMI) levels, we analysed a database of 9338 subjects from the National Integrated Project for Prospective Observation of Non-communicable Disease and its Trends in the Aged, which was originally conducted a baseline survey in 1980 and followed up in 1999. Relative risk (RR) and a 95% confidence interval (CI) of death from total stroke, cerebral infarction, and intracerebral haemorrhage after adjusting for age, sex, serum cholesterol, albumin, glucose, the use of antihypertensive agents, a past history of diabetes, BMI, smoking, and drinking were estimated with the Cox-proportional hazard model in the BMI tertile groups of a representative Japanese population. Cutoff points of BMI tertiles are 21.2 and 23.8 kg/m2. The results indicated that a 10 mmHg systolic blood pressure (SBP) increase was associated with mortality from intracerebral haemorrhage at low and middle BMI groups (RR= 1.38 and 1.23; 95% CI=1.17-1.62 and 1.03-1.47, respectively). SBP was positively associated with mortality from cerebral infarction in middle and high BMI groups (RR=1.19 and 1.21; 95% CI=1.06-1.33 and 1.06-1.38, respectively). The effects of diastolic blood pressure on intracerebral haemorrhage and infarction had the same tendency as those of SBP. These results suggested that the causal effect of blood pressure on stroke subtypes might be modified by BMI.

PCDDs, PCdfs and Co-PCBs in human breast milk samples collected in Tokyo, Japan

AIM

To observe the distribution of PCDD/Fs and Co-PCBs in samples of human breast milk collected in Japan.

METHODS

Using high-resolution gas chromatography, milk samples for polychlorinated dibenzo-p-dioxins (PCDDs; 14 congeners), polychlorinated dibenzofurans (PCDFs; 15 congeners) and coplanar polychlorinated biphenyls (Co-PCBs; 12 congeners) from 240 mothers residing in Tokyo were analysed. There were 120 donors each of primiparae and secundiparae, each group including 60 donors aged 25 to 29 y ("the younger group") and 60 aged 30 to 34 y ("the older group"). Individual milk samples (about 50 ml) were obtained 30 d after delivery in 1999 and in 2000.

RESULTS

The mean toxic equivalent (TEQ) level of PCDD/Fs (the sum of PCDDs and PCDFs) was 14.9 pg TEQ/g fat, of Co-PCBs 10.6 pg TEQ/g fat, and the total sum of PCDD/Fs and Co-PCBs was 25.6 pg TEQ/g fat. The mean TEQ levels of PCDD/Fs, Co-PCBs, and total PCDD/Fs and Co-PCBs were higher in primiparae than in secundiparae. In each of these, the levels were higher in the subgroup of older mothers. In the secundiparae, the mean levels were lower in the group of mothers who had breastfed their first babies than in those who bottle-fed or partly bottle-fed their first born.

CONCLUSIONS

The concentrations of PCDD/Fs and Co-PCBs in the breast milk of Japanese women were slightly lower than those described in previous studies conducted in Japan and other countries; and the concentrations of PCDD/Fs and Co-PCBs in the breast milk were influenced mainly by the mother's age and nursing history.

Population attributable fraction of smoking to low birth weight in Japan

BACKGROUND

The purpose of this study is to quantify the population attributable fraction of active and passive smoking for low birth weight in Japan.

METHODS

A population-based case-control study was conducted by mailing self-report questionnaires. The cases were all singleton low birth weight babies who were born between 1 January 1998 and 30 June 1999 in Tochigi prefecture, Japan. The controls were randomly selected from all singleton babies who were born during the same period as cases in the prefecture.

RESULTS

The number of cases and controls were 286 and 404, respectively. Population attributable fractions of active smoking during and before pregnancy were 7.0% and 8.8%, respectively. Population attributable fraction of passive smoking at home was 15.6% and at the workplace was 1.1%. Combined population attributable fraction of both active and passive smoking was 17.3%.

CONCLUSION

Public education to eliminate passive smoking for pregnant women and smoking prevention in adolescence is very important in order to reduce the risk of low birth weight.

Use of laboratory data to identify risk factors of giant coronary aneurysms due to Kawasaki disease

BACKGROUND

Although some laboratory findings are known to be indicators of the risk of giant coronary aneurysm formation among Kawasaki disease patients, an appropriate cut-off point to predict aneurysm formation is not clear.

METHODS

One hundred and five patients with giant coronary aneurysms were selected from the 15th and 16th nationwide surveys of Kawasaki disease in Japan. A total of 2936 patients without Kawasaki disease were recruited from a single hospital as a control group. Odds ratios were calculated for six laboratory data with specific values as cut-off points. Receiver operating characteristic (ROC) curves were observed to determine the most appropriate laboratory tests and cut-off points.

RESULTS

Hematocrit, leukocyte count, neutrophil proportion, and hemoglobin had one or more peaks of odds ratio for specific cut-off points, but they did not have a clear cut-off point for the predictor according to the receiver operating characteristic curves. Alanine aminotransferase (ALT) increased the risk of giant coronary aneurysms continuously so no clearly appropriate cut-off point was identified. Serum sodium concentration of 135 mEq/L had a peak of odds ratio, and those with <135 mEq/L had the highest odds ratio (4.78). This value seemed appropriate with a sensitivity of 78% and specificity of 57%, although the predictive positive value was as small as 5%.

CONCLUSION

The author's propose that a serum sodium concentration of <135 mEq/L at the patient's first visit to hospital may be a predictor of giant coronary aneurysms due to Kawasaki disease.

Birth cohort effect of the mortality rate from congenital heart disease in Japan

BACKGROUND

The mortality rate from congenital heart disease in Japan had decreased partly because the great improvement of medical treatment and care. Therefore, the patients who would have died of congenital heart disease in younger age in the past may be alive to be adult, and the number of adults with congenital heart disease might increase. If the management of such adults did not improve, the mortality rate from congenital heart disease might increase because of the increased number.

METHODS

Using the Japanese vital statistics from 1960 through 1999, we observed the time series of the mortality rate from congenital heart disease by age and sex. The birth cohort consisted of those who were bone in 5-year period starting in 1960. The mortality rate was the sum of the number of death in every five years divided by the population of the center year.

RESULTS

The transition of the mortality rate from congenital heart disease for age group 0 to 4 years was decreased since 1973. Other age groups showed decreased mortality rate since late 1960's. The birth cohort analyses showed that the mortality rate of each birth cohort was decreased as time passed, especially the age group 5 to 9 years old and 10 to 14 years old.

CONCLUSION

Birth cohort effect of mortality from congenital heart disease exists in Japan.

Analyses of fatal cases of Kawasaki disease in Japan using vital statistical data over 27 years

BACKGROUND

Chronological changes in mortality and case fatality rates from Kawasaki disease covering an extended period in Japan are still unknown.

METHODS

We analyzed 679 deaths of patients in Japan whose underlying cause was Kawasaki disease, by using the data of vital statistics between 1972 and 1998.

RESULTS

The male-to-female ratio of the number of deaths was 2.07 and the mean age at death in males was higher. Two unusual increases in the epidemic years, 1982 and 1986, were observed in the chronological changes of the number of deaths. The mortality rate of males was higher than that of females, with a few exceptional years, and the annual mortality rates were high in three epidemic years. The age-specific mortality rate was highest in infants under one year of age. Prefectures with high mortality rate clustered in some regions. The case fatality rate decreased annually, declining to as low as 0.2% among those who were born in 1986 and thereafter; and unusual increases in the case fatality rate affected by these three epidemic years were not repeated.

CONCLUSIONS

The case fatality rate from Kawasaki disease in Japan decreased during the 27 years of observation: improvements in treatment might account for this.

Case-control study of giant coronary aneurysms due to Kawasaki disease

BACKGROUND

Epidemiologic features of the formation of giant coronary aneurysm due to Kawasaki disease and its risk factors are not still clear.

METHODS

One hundred and five patients with giant coronary aneurysms were selected from the 15th and 16th nationwide surveys of Kawasaki disease in Japan. With all other patients reported from the same hospital as a control group, odds ratios (OR) were calculated for some potential risk factors.

RESULTS

Some factors affecting the formation of giant coronary aneurysms were revealed. Of these factors, the following were considered to be useful for the treatment of patients with Kawasaki disease: male sex (OR compared with females = 1.99), 0 years old (OR compared with 1-2 years = 1.71), visiting the hospital on 1-3 days of illness (OR compared to 4-6 days = 1.72), leukocyte count (OR with 1000 /mm3 increase = 0.56), neutrophil concentration among leukocyte (OR with 10% increase = 1.11), hemoglobin concentration (OR with 1 mg/dL increase = 0.73), alanine aminotransferase level (ALT; OR with 10 IU/dL increase = 1.02) and serum sodium level (OR with 1 mEq/L increase = 0.80).

CONCLUSIONS

The observation of 105 cases with giant coronary aneurysms due to Kawasaki disease reported in the nationwide survey provides information about some risk factors and other considerations about the aneurysms.

Respiratory symptoms correlating to smoking prevalence: the National Nutrition Survey and the National Life-style Survey in Japan

BACKGROUND

Although the fact that smoking habits have adverse effects on health, whether the high proportion of smokers elevates the prevalence of symptoms relating to the smoking in a community is still unknown.

METHODS

An ecologic study about whole Japan was conducted. Age-adjusted smoking prevalence was calculated using the National Nutrition Survey data from 1986 through 1995 by prefecture and sex. Age-adjusted respiratory symptom prevalence were observed using the National Life-style Survey data in 1995. Correlation among 46 and/or 43 prefectures was examined by sex.

RESULTS

There was a negative correlation between smoking prevalence and wheezing prevalence among males (r = -0.301). Among females, positive correlations were observed on the symptoms of nasal obstruction (r = 0.355), nasal discharge (r = 0.344), sore throat (r = 0.481), cough (r = 0.350), sputum (r = 0.594), wheezing (r = 0.451), palpitation (r = 0.363), dyspnea (r = 0.587), and frontal chest pain (r = 0.472).

CONCLUSIONS

Smoking prevalence was deeply related to respiratory symptoms among females in Japan.

Factors relating to the cardiac sequelae of Kawasaki disease one month after initial onset

This study aimed to determine the risk factors related to the presence of cardiac sequelae 1 mo after initial onset and to examine the preventive effect of the early administration of high-dose gamma-globulin (GG) on cardiac sequelae in patients with Kawasaki disease. Patients treated with high-dose GG of 2000 +/- 100 mg kg(-1) were selected as subjects from the 15th nation-wide survey in Japan. Univariate and logistic multiple variable analyses were used to test the effects of background variables such as age and gender, variables relating to laboratory findings such as the percentage of neutrophil leucocytes, and variables relating to the GG treatment on the presence of cardiac sequelae. The odds ratios were significantly higher for males (1.48), those younger than 1 y of age (1.71), recurrent cases (2.42), and those with a low haematocrit (<32.5%) (1.45) and high percentage of neutrophil leucocytes (>68%) (1.63). The odds ratio was low for those who started GG administration in less than 6 d from onset between the patients with and without cardiac sequelae. The odds ratio for the duration of GG treatment was not significantly different between those with and without cardiac sequelae.

CONCLUSION

Patients who received early administration of GG, less than 6 d from onset of the disease, had a lower risk than those received GG more than 6 d from the onset. The percentage of neutrophil leucocytes and the haematocrit level are useful indicators in predicting the development of cardiac sequelae.

Giant coronary aneurysms due to Kawasaki disease: a case-control study

BACKGROUND

Epidemiologic features of giant coronary aneurysm due to Kawasaki disease and its risk factors are still not clear.

METHODS

Sixty-six patients with giant coronary aneurysms were reported to a 15th nationwide survey of Kawasaki disease in Japan. With all other patients treated in the same hospital as a control group, odds ratios were calculated for certain potential risk factors.

RESULTS

Infant males aged less than 1 year,neutrophil concentration among leukocyte, late administration of intravenous gammaglobulin (IVGG) therapy and additional administration of IVGGwere considered as risk factors of giant coronary aneurysms due to Kawasaki disease. In univariate analysis, use of IVGG therapy and a large amount of IVGG (2500+ mg/kg)elevated the risk, whereas the relationship disappeared after the adjustment.

CONCLUSIONS

The observation of 66 cases with giant coronary aneurysms due to Kawasaki disease reported to the nationwide survey provides some risk factors and consideration about the aneurysms.

Trends in asthma morbidity and mortality in Japan between 1984 and 1996

PURPOSE

To determine whether the increased prevalence of asthma in Japan has influenced its mortality.

MATERIALS AND METHODS

A descriptive study was conducted by the data obtained from Patient Survey and Vital Statistics of Japan between 1984 and 1996. Asthma fatalities were expressed as the number of deaths from asthma per 100,000 asthmatic patients receiving medical treatment on the day when the survey was conducted.

RESULTS

Mortality, prevalence and asthma fatalities showed different changing patterns among several age groups. Asthma mortality for the 10-24 and 25-44 year-old groups increased during the study period, while for other age groups, it decreased. The prevalence increased for all groups classified by age and sex. Asthma fatalities peaked in 1987 among the 10-24, 25-44 and 45-64 year-old groups, and decreased for others throughout the study period.

CONCLUSIONS

There is a possibility that an age-specific phenomenon is at work here because asthma mortality increased only in the 10-24 and 25-44 year-old groups, although the prevalence of asthma increased in all groups, whether classified by age or sex. The asthma fatality of the 10-24, 25-44 and 45-64 year-old groups peaked in 1987: it is conceivable that this was influenced by the particular drug therapy used. The increase in asthma mortality in the 10-24 and 25-44 year-olds might be influenced by the increased prevalence.

Mortality from congenital cardiovascular malformations in Japan, 1968 through 1997

Long-term mortality from congenital cardiovascular malformations (CCVM) remains unknown in most countries. Age- and sex-specific mortality rates from CCVM in Japan from 1968 through 1997 were determined from analyses, with official permission, of individual death records held by the Japanese Government. CCVM with chromosomal anomalies were not included. The number of deaths analyzed was 82,919. The mortality rate declined by 64% from 3.36 per 100,000 population in 1968 to 1.22 in 1997, largely because of a decrease in mortality among patients under 20 years of age. Infant mortality remained high until 1978, then sharply declined from 1979 to 1987 with the advent of 2-dimensional echocardiographic diagnosis and prostaglandin El therapy. The cumulative mortality rates in the first 20 years of life were expected to decline among cohort members born after 1978. In contrast, the mortality rates for subjects over 20 years of age increased during the 30-year study period. Mortality rates were higher for males than for females. The mortality rate among young patients with CCVM is expected to decline still further, suggesting that many if not most children with CCVM will survive to adulthood.

Incidence survey of Kawasaki disease in 1997 and 1998 in Japan

OBJECTIVE

To describe the results of a nationwide epidemiologic survey of Kawasaki disease for the 2-year period 1997 and 1998.

DESIGN

We sent a questionnaire to all hospitals with 100 beds or more throughout Japan (2663 hospitals) requesting data on patients with Kawasaki disease. Study items included name, sex, date of birth, date of initial hospital visit, diagnosis, address, recurrence, sibling cases, gammaglobulin treatment, and cardiac lesion in the acute stage or 1 month after onset.

RESULTS

Of the 2663 hospitals, 68.5% responded, reporting 12 966 patients-7489 males and 5477 females. Of the total patients reported, 6373 (incidence rate of 108.0 per 100 000 children <5 years old) occurred in 1997, and 6593 (111.7) in 1998. More than one half of the patients (54.9%) were <2 years old and 81.6% were <4 years old. In males, the incidence rates of cardiac lesions were 27.2 in the acute stage and 10.1 a month after onset. In females, the rates were 16.7 and 5.2, respectively. The incidence rates of cardiac lesions were highest in the youngest age group (<6 months old) both in the acute stage and 1 month after onset. The rates decreased with increasing ages. Although frequency of giant aneurysms was not high at the acute stage, it did not decrease 1 month after onset.

CONCLUSION

The incidence rates have been steadily increasing for 11 years since 1987. The rate in 1998 was over 1.5 times higher than that in 1987. The age and sex distributions were identical in each survey. Although most of the cardiac lesions at the acute stage decreased to half or less 1 month after onset, giant aneurysms did not decrease and existed persistently after 1 month.

A multicenter collaborative study on the risk factors of cardiac sequelae due to Kawasaki disease: a one-year follow-up study

OBJECTIVE

To measure the prevalence of cardiac sequelae 1 y after the onset of Kawasaki disease and determine the risk factors associated with these cardiac sequelae.

MATERIAL AND METHODS

1594 patients who initially visited one of the 87 target hospitals in 1996 for Kawasaki disease participated. Selection of the target hospitals was based on a nationwide survey. The patients were followed-up and information concerning cardiac sequelae occurring within 1 y of onset was obtained by mail survey.

RESULTS

The prevalence of cardiac sequelae 1 mo after onset was 10.2% and decreased to 4.2% in 1 y. The prevalence was higher among males than females and higher in patients less than 1 y and 5 ys or older than in 1-4 year-olds. Of the patients with cardiac sequelae at 1 mo, the sequelae disappeared in 60.7% after 1 y. Analysis revealed low serum albumin as a risk factor related to the occurrence of cardiac sequelae 1 y after onset. Of the 1594 patients, 10 had giant anuerysms and 3 had a fatal outcome.

CONCLUSIONS

Approximately 60% of cardiac sequelae due to Kawasaki disease that developed within 1 mo after onset disappeared in 1 y. The odds ratio was significantly higher among patients with a low serum albumin level 1 y after onset.

A case-control study of Creutzfeldt-Jakob disease in Japan: transplantation of cadaveric dura mater was a risk factor

A case-control study was conducted to reveal the relative risk of cadaveric dura mater graft transplantation for Creutzfeldt-Jakob disease. Fifty-two cases with Creutzfeldt-Jakob disease that were reported to the surveillance of the disease, and 102 age- and sex-matched hospital controls were selected. Information on family history, occupations, and medical history was collected. Eight cases and no control had a history of cadaveric dura mater graft transplantation. Surgical operations without the dura mater graft, blood transfusion, and acupuncture did not elevate the risk.

Repeatability of the questionnaire for the aging level indices

The purpose of the study is to confirm repeatability of the series of self-administrating questions, which can be applied in large community populations. In 1994 and 1995, two surveys were conducted for the residents at Minamikawachi, Japan with a same questionnaire. The number of respondents for the both surveys was 887. Kappa statistics of all items of the series of questions for aging level indices were significantly high. Kappa statistics were over 0.4, and repeatability is good or excellent in 28 items of all the 45 items. The statistics of the items for medical treatments of chronic diseases were high, in such as diabetes (0.846) and hypertension (0.604). For activity of daily livings, such as shopping (0.619), kappa statistics were also high, but that of eating (0.162) was low. The statistics of subjective symptoms were moderate, however, that of impairment of hearing (0.672) was high, and that of decline of interest in opposite sex (0.256) were low. On the other hand, kappa statistics of acute diseases were low, in such as bone fracture (0.073). Correlation coefficients of the comprehensive aging level indices are around 0.6 among the people of 65 years old or older. In conclusion, the repeatability of the questions and indices were good, and they are appropriate to apply to communities.

[Case-control study of risk factors for cedar pollinosis among parents of 3-year-old children]

PURPOSE

To identify risk factors associated with cedar pollinosis among parents of three-year-old children.

METHODS

The subjects were parents whose children underwent health examination at the age of three years in September and October 1997 in Tochigi prefecture. We distributed questionnaires to the examinees beforehand with the request that they be filled in and brought to the examination site. Information on parents' environmental factors (place of residence, type and structure of housing, and distance from roads with heavy traffic), and mothers' past history and family history of allergic diseases was obtained. We defined cedar pollinosis in terms of three symptoms, sneezing, nasal discharge, and nasal obstruction, between February and May. Controls were those who did not have any of the three symptoms. Environmental factors were assessed with univariate and multivariate analyses using unconditional logistic models. Maternal genetic factors were also analyzed with odds ratios and 95% confidence intervals calculated for each. We also compared odds ratios of environmental factors between groups with and without genetic factors.

RESULTS

Of the parents of children taking the health examination, 90.2% took part (2,968 of 3,291 couples). Information was obtained from 2,846 mothers and 2,905 fathers. Mother and father cases were 312 and 229, and controls were 1,857 and 1,934, respectively. For the univariate analysis of environmental factors, place of residence (residential area/agricultural area), type of housing (apartment complex/solitary house), structure (reinforced concrete building/wooden house), and distance from heavy traffic (< 100 m/100 m+) were positively related to cedar pollinosis. For the multivariate analysis using unconditional logistic models, the odds ratio was significantly high for distance from heavy traffic (< 100 m/100 m+) among fathers. Mothers' past history and family history of allergic diseases showed high odds ratios for cedar pollinosis. We classified groups with and without past and family histories of allergic diseases (group with and without genetic factors) for assessment with multivariate analyses. Odds ratios for the group with an allergic history were higher than for those without such a history, but difference for factors such as, distance from heavy traffic type of housing, and structure were not statistically significant.

CONCLUSION

Risk of cedar pollinosis increases with distance from heavy traffic among fathers. Mothers with histories of allergy show slightly elevated odds ratios for environmental factors, but without statistic significance.