National Health Insurance Beneficiaries Research Articles

Effect of Sociodemographic Factors, Cancer, Psychiatric Disorder on Suicide: Gender and Age-specific Patterns

We examined the effect of sociodemographic factors, cancer, and psychiatric disorders on suicide by gender and age-specific patterns in South Korea. The study is a case-control study. Claim data was obtained from the national health insurance database and national death registration database. The number of people who committed suicide was 11,523, which was matched with a control group consisting of ten times as many people at 115,230 selected from the national health insurance and medical aids beneficiaries. The medical utilization of the case group was one year before death and that of the control group was from July 1,2003 to June 30, 2004. Four variables-address, economic status, presence of a psychiatric disease, and cancer-were used in multiple logistic regression analyses. Living in cities or in rural areas showed a greater risk for suicide than living in a metropolitan city. Low economic status, the presence of a psychiatric disorder, and cancer were also statistically meaningful risk factors for suicide. The three major psychiatric diseases, schizophrenia, alcohol abuse, and bipolar disorder, were meaningful in all age groups, but the scale of the odds ratio differed by the age group. Only the psychiatric disorder variable was meaningful in the adolescent group, whereas a psychiatric disorder and economic status were meaningful for the young adult group, and all variables were meaningful for the middle-aged group. A psychiatric disorder and cancer were meaningful in the elderly group, economic status was meaningful for male subjects, and address was meaningful for female subjects. Factors such as living in city or rural areas, low economic status, the presence of a psychiatric disorder, and cancer were statistically meaningful risk factors in suicide. These factors also differed by age group. Therefore, policymakers should establish policies for suicide prevention that are relevant for each age group.

日本における魚摂取と前立腺癌罹患に関する前向きコホート研究

Fish intake may reduce the risk of prostate cancer. However, the results of previous prospective cohort studies have been inconsistent, and almost all have been undertaken in Western countries, where total fish intake is low. We therefore investigated the association between fish intake and the risk of prostate cancer in a prospective cohort study in Japan. We delivered a self-administered questionnaire including items on dietary intake (40-item food frequency questionnaire [FFQ]), and various lifestyle habits, between October and December 1994 to all male National Health Insurance (NHI) beneficiaries aged 40-79 years in Japan. Usable questionnaires were returned from 24,895 (94%) of the participants. We divided the participants into quartiles based on their self-reported fish intake. We used the Cox proportional hazards model to estimate the hazard ratio (HR) and 95% confidence interval (CI) of prostate cancer incidence according to fish intake, after adjustment for potential confounders. We identified 95 prostate cancer cases during 7 years of follow-up, to the end of December 2001. An inverse association was observed between fish intake and the risk of prostate cancer. The multivariate HRs (95% CI) of prostate cancer across increasing quartiles of fish intake were 1.00, 0.92 (0.48-1.76), 0.73 (0.42-1.28), and 0.72 (0.40-1.33) (P for trend = 0.23). Among participants aged 40-69 years, the multivariate HRs (95% CI) of prostate cancer across increasing quartiles of fish intake were 1.00, 1.26 (0.51-3.11), 0.86 (0.38-1.94), and 1.01 (0.43-2.34) (P for trend = 0.83). On the other hand, among participants aged 70 years or older, the corresponding multivariate HRs (95% CI) were 1.00, 0.63 (0.23-1.69), 0.60 (0.27-1.30), and 0.44 (0.18-1.11) (P for trend = 0.08). The risk of prostate cancer tended to decrease among those aged 70 years or older although it was not significant. The relation was not seen in those aged 40-69 years old.

The joint impact of cardiovascular risk factors upon medical costs

Objective. The joint impact of obesity, hypertension, and hyperglycemia upon medical costs is not well known. Our objective was to evaluate the joint impact of these cardiovascular risk factors upon medical costs in the rural Japanese population. Methods. The data were derived from a 6-year prospective observation of National Health Insurance beneficiaries in rural Japan. Data on blood chemistry tests, blood pressure, weight, and height were obtained from an annual health check-up provided by the local municipalities in 1995. We prospectively collected data on medical costs over a 6-year period for 12,340 subjects (5306 men and 7034 women) without prior histories of cardiovascular disease or cancer. Results. Mean medical costs for individuals being overweight/obese, hypertensive, and hyperglycemic were 91.0% higher than those for individuals without any of these three cardiovascular risk factors. In this cohort, 17.2% of total medical costs were attributable to these three risk factors. Conclusion. Overweight/obesity, hypertension, and hyperglycemia could have a large impact on health care resources in rural Japan.

Medical costs of obese Japanese: a 10-year follow-up study of National Health Insurance in Shiga, Japan

For the Japanese population, a body mass index (BMI) of 25.0-29.9 is classified as obesity and is a risk factor for cardiovascular disorders such as hypertension. A cohort study to clarify obesity costs for a Japanese population was conducted utilizing baseline BMI and medical costs over a 10-year follow-up period. The participants were 4502 community dwelling Japanese National Health Insurance (NHI) beneficiaries aged 40-69 years. According to their baseline BMI values (kg/m(2)), participants were classified into the following three categories: BMI < 18.5, 18.5 < or = BMI < 25.0 and 25.0 < or = BMI. Medical costs per person per month were compared among the three categories. Excess medical costs attributable to the 25.0 < or = BMI category compared to the 18.5 < or = BMI < 25.0 category were estimated. Approximately 20% of the Japanese population studied had a BMI of 25.0 or over. A J-shaped relationship between BMI and personal total medical costs was observed. Personal total medical costs per month determined from the 10-year follow-up in each category were 189 Euros (BMI < 18.5), 134 Euros (18.5 < or = BMI < 25.0) and 155 Euros (25.0 < or = BMI). A J-shaped pattern was observed after adjusting for age, sex, smoking and drinking habits, and excluding early deceased participants. Furthermore, smoking habit did not modify the J-shaped pattern of total medical costs. The estimated excess medical costs for the 25.0 < or = BMI category represented 3.1% of the total medical costs for the entire study population (634 105 Euros). The Japanese NHI beneficiaries with a BMI of 25.0 or over showed increased medical costs compared to those with a BMI of 18.5-24.9.

Comparing medical expenditures of smokers and nonsmokers in studies using direct methodology in Japan

Numerous epidemiologic studies have revealed that smoking is a significant risk factor of many diseases. Some studies reported increase in medical expenditure by smoking using odds or hazard ratios between smoking and diseases in epidemiologic studies. The purpose of the present study is to investigate the ratios of mean medical expenditures between smokers and nonsmokers from studies conducted observing medical expenditure directly in Japan. We collected 11 published articles of studies conducted observing medical expenditures of smokers and nonsmokers directly in Japan. The weighted geometric mean of ratios between age-adjusted mean medical expenditures for smokers and nonsmokers of National Health Insurance and Government-Managed Health Insurance beneficiaries which included many elderly individuals was somewhat greater than 1.0, while the value of Society-Managed Health Insurance that included a small number of elderly people was less than 1.0. Smoking and smokers' indifference to health increase the medical expenditure of the smokers, especially elderly smokers. It was not determined, however, whether the mean medical expenditure of smokers is actually greater than that of nonsmokers.

Effect of Combined Cardiovascular Risk Factors on Individual and Population Medical Expenditures

Although obesity is required for some criteria defining metabolic syndrome, clustering of other risk factors also indicates an increased risk of cardiovascular disease. Whether the relationship between cardiovascular risk factor clustering and medical expenditures differs with body mass index (BMI) requires investigation, especially in a population with a low prevalence of obesity such as that in Japan. A 10-year cohort study of 4,478 Japanese National Health Insurance beneficiaries aged 40-69 years in a community between 1990 and 2001 was carried out in the present study. The clustering of cardiovascular risk factors showed a positive and graded relationship to personal medical expenditures in participants who are overweight (BMI > or =25.0) and normal weight (BMI <25.0). The individual medical expenditures per month were 1.7-fold higher for participants with 2 or 3 risk factors and overweight than for those without these factors (26,782 vs 15,377 Japanese yen). Differences in the geometric means were similarly significant after adjustment for other confounding factors. However, the excess medical expenditures by risk clustering of normal weight categories within the total medical expenditures were higher than those of overweight categories because more participants were of normal weight. Cardiovascular risk factor clustering and being overweight can be a useful predictor of medical expenditures in a Japanese population.

The Value of Combining Serum Alanine Aminotransferase Levels and Body Mass Index to Predict Mortality and Medical Costs: a 10-year Follow-up Study of National Health Insurance in Shiga, Japan

BACKGROUNDEvidence suggests that the predictive value of serum alanine aminotransferase (ALT) levels for prognosis, measured by indices such as all-cause mortality and medical costs, may be modified by body mass index (BMI). However, the relationship between serum ALT and BMI has not been satisfactorily elucidated.METHODSFour thousand, five hundred and twenty-four community dwelling Japanese National Health Insurance beneficiaries, 40-69 years old, were classified into five categories according to their serum ALT levels (IU/L) (ALT<20, 20≤ALT<30, 30≤ALT<40, 40≤ALT<50 and 50≤ALT) and followed for 10 years. Hazard ratios for all-cause mortality, with reference to the lowest serum ALT category, and medical costs per person were evaluated for each serum ALT category after analyzing interactions between serum ALT levels and BMI for all-cause mortality and for medical costs.RESULTSA significant interaction between serum ALT levels and BMI was observed. In participants below the median BMI, positive, graded relationships were identified between serum ALT levels and all-cause mortality as well as between serum ALT levels and personal medical costs. The multivariate-adjusted hazard ratio in the “50≤ALT” category showed an approximately 8-fold increase. However, in the participants at or above the median BMI, no significant relationships between serum ALT levels and all-cause mortality or personal medical costs were identified.CONCLUSIONSIn these Japanese participants, the predictive value of serum ALT levels for prognosis was more evident if BMI was taken into account. A combination of high serum ALT levels and below median BMI was associated with excess mortality and medical costs.

Antibiotic prescribing by ambulatory care physicians for adults with nasopharyngitis, URIs, and acute bronchitis in Taiwan: a multi-level modeling approach

Imprudent prescribing of antibiotics in ambulatory care in Asia is of great concern. However, an adequate understanding of factors associated with antibiotic prescribing patterns in Asia has not been achieved. Our aim was to identify patient and physician characteristics that influence antibiotic prescribing for adults with nasopharyngitis (common colds), upper respiratory tract infections (URIs) or bronchitis in Taiwan. Generalized Estimating Equations (GEE) were used to analyze all 128,260 episodes of common colds, URIs and bronchitis generated by a random sample of 137,935 adult National Health Insurance (NHI) beneficiaries (> or = 18 years old) in Taiwan in 2000. Multivariate analysis results revealed substantial variations across different physician groups. Physician age and accreditation level of the physician's practice setting were the characteristics most associated with prescribing of antibiotics at the initial encounters for these episodes of care. Urban practising physicians (adjusted OR 1.69, 95% CI 1.29-2.21) and those who were self-dispensing or with on-site pharmacists (adjusted OR 1.32, 95% CI 1.19-1.46) were also higher prescribers of antibiotics for adults. Other significant physician predictors included physician specialty, patient volume, and ownership of practice setting. Results suggest that both accessibility to updated medical information and economic incentives of the attending physician may shape prescribing of antibiotics in ambulatory care in Taiwan. Interventions should be developed to influence these modifiable factors to reduce antibiotic prescriptions of questionable value.

Impact of Hypertension on Medical Economics: A 10-Year Follow-Up Study of National Health Insurance in Shiga, Japan

Hypertension and related cardiovascular diseases may lead to an increase in medical costs for patients. We attempted to clarify the relationship between hypertension and long-term medical costs by a cohort study utilizing existing data as well as baseline blood pressures and medical costs over a 10-year period. The participants included 4191 Japanese National Health Insurance beneficiaries aged 40-69 years, living in one area, who were not taking anti-hypertensive medication and did not have a history of major cardiovascular disease. They were classified into four categories according to their blood pressure. We evaluated the mean medical costs per month, cumulative hospitalization, and all-cause mortality for each blood pressure category. Hypertension-related medical costs attributable to hypertensive individuals, as compared to normotensive individuals, were estimated. There was a positively graded correlation between blood pressure and personal total medical costs, especially for men. The odds ratio for cumulative hospitalization and hazard ratio for all-cause mortality in severe hypertensive men were also higher than those in normotensive men. However, the hypertension-related medical costs for mild to moderate hypertensives were higher than those for severe hypertensives. The hypertension-related medical costs for all hypertensives accounted for 23.7% of the total medical costs for the Japanese population. In conclusion, high blood pressure was a useful predictor for excess medical costs; moreover, concomitant hypertension, regardless of the grade, increased the medical costs of Japanese National Health Insurance beneficiaries.

Impact of alcohol consumption upon medical care utilization and costs in men: 4‐year observation of National Health Insurance beneficiaries in Japan

The purpose of the present study was to examine the association between alcohol consumption and in-patient and out-patient care utilization and its costs, respectively. The present data were derived from a 4-year prospective observation of National Health Insurance beneficiaries in rural Japan. A total of 17 497 men aged 40-79 years were analysed, after excluding subjects who at the baseline reported having had at least one of four chronic diseases: stroke, myocardial infarction, liver disease and cancer. Alcohol intake was classified into five groups, not including ex-drinkers: life-long abstainers and ethanol intakes of 1-149 g/week, 150-299 g/week, 300-449 g/week, and > or = 450 g/week. The hospital days and in-patient care cost showed a U-shaped relationship with alcohol consumption. In-patient cost was highest for those consuming more than 450 g/week [ pound 74.96, 95% confidence interval (CI): 54.39, 95.52] and for life-long abstainers ( pound 69.16, 95% CI: 62.08, 77.83), and lowest for those consuming 150-299 g/week ( pound 51.69, 95% CI: 45.33, 58.04). In-patient use by age specific analysis also showed a U-shape at all ages, and was lowest for those consuming 1-149 g/week in youngest age group. In contrast, the number of physician visits and out-patient cost showed an inverse linear relationships with alcohol consumption. This study suggests that in-patient use shows a U-shaped curve and out-patient use shows an inverse linear relationship to alcohol consumption.

Joint impact of health risks on health care charges: 7-year follow-up of National Health Insurance beneficiaries in Japan (the Ohsaki Study)

Background. The objective of this study was to examine the joint impact of modifiable health-risk factors such as smoking, obesity, and physical inactivity on direct health care charges. Method. We conducted a population-based prospective cohort study, with follow-up from 1995 to 2001. The participants were Japanese National Health Insurance (NHI) beneficiaries (26,110 men and women aged 40–79 years). Results. ‘No risk’ group defined as never-smoking, body mass index (BMI) 20.0–24.9 kg/m 2, and walking for ≥1 h/day had mean health care charges of $171.6 after adjustment for potential confounders. Compared with this group, the presence of smoking (SM; ever-smoking) alone, obesity alone (OB; BMI ≥25.0 kg/m 2), or physical inactivity (PI; walking for <1 h/day) alone were associated with a 8.3%, 7.1%, or 8.0% increase in health care charges, respectively. The combinations of the risks of SM and OB, SM and PI, OB and PI, and SM and OB and PI were associated with a 11.7%, 31.4%, 16.4%, and 42.6% increase in charges, respectively. Conclusion. Interventions to improve modifiable health-risk factors may be a cost-effective approach for reducing health care charges as well as improving people's health.

Impact of walking upon medical care expenditure in Japan: the Ohsaki Cohort Study.

Physical activity is expected to reduce medical costs by lowering the risk for a variety of chronic diseases. However, little is known about the actual magnitude of medical cost saved by physical activity. We attempted to quantify the association between time spent walking and medical care costs, based on a 4-year prospective observation of National Health Insurance (NHI) beneficiaries in rural Japan. In 27 431 Japanese men and women, aged 40-79 years, who had no functional limitation or conditions interfering with physical activity at the baseline survey in 1994, we ascertained all hospitalizations, outpatient visits, and the costs through computerized linkage with NHI claims history files between January 1995 and December 1998. Medical costs significantly reduced with longer time spent walking. Per capita medical cost was pound 111.80 per month (95% CI: 109.3, 114.2) in those who walked for < or =30 minutes/day, pound 108.10 (95% CI: 105.7, 110.5) in those who walked for 30 minutes-1 hour, and pound 97.30 (95% CI: 95.5, 99.0) in those who walked for > or =1 hour, after multivariate adjustment of potential confounders. This prospective study in Japan indicated that time spent walking was significantly associated with lower medical costs.

Impact of smoking habit on medical care use and its costs: a prospective observation of National Health Insurance beneficiaries in Japan.

To quantify excess medical use associated with smoking, a large prospective cohort study is needed. The authors examined the impact of smoking on medical care use in a large population-based cohort with an accurate data collecting system in Japan. The data were derived from a 30-month prospective cohort study of 43,408 National Health Insurance beneficiaries aged 40--79 years living in a rural Japanese community. The smoking habit of beneficiaries was assessed in a baseline survey at the end of 1994. Medical care use and its costs were monitored by linkage with the National Health Insurance claim history files since January 1995. Male smokers incurred 11% more medical costs (after adjustment for age, physical functioning status, alcohol consumption, body mass index and average time spent walking) than 'never smokers' but for female smokers and never smokers the costs were almost the same. This difference was mainly attributable to increased use of inpatient medical care among smokers, especially in males, where per month cost of inpatient care was 33% higher in smokers. Age-group specific analysis in men showed that excess mortality and excess medical cost ratio for smokers peaked in those aged 60--69 years. Smokers consume excess medical care. Among the population aged 45 years and over, about 4% of total medical costs were attributable to smoking. To pursue both better health and lower medical costs for the nation, a comprehensive programme to reduce tobacco use is needed.

Medical cost for disability: a longitudinal observation of national health insurance beneficiaries in Japan.

To measure the impact of disability on the use of medical care and its costs. A 1-year prospective cohort study of National Health Insurance beneficiaries in a rural Japanese community. Their physical function was examined by the Medical Outcomes Study questionnaire at the end of 1994; medical care and its costs were then monitored for 1 year. Participants were the 49,364 subjects, aged 40 to 79 years, who were beneficiaries of National Health Insurance and lived in the catchment area of Ohsaki Public Health Center, Miyagi, Japan. The subjects were mainly farmers, self-employed persons, housewives, or pensioners. Medical care utilization (number of outpatient visits and days of inpatient care) and the costs for each subject were obtained from National Health Insurance Claim History files. These measurements were collected from January to December 1995, and the relationship between physical functioning levels and medical costs was analyzed. The medical costs per capita increased with poorer physical function. Medical costs among those with limitations in performing self-care increased by 4 times in men and 3 times in women compared with those with no functional limitation. In this cohort, the 4.3% of the subjects who were dependent in self-care used 15% of the total inpatient days and 10% of the total medical costs. Treatment of patients with disability requires a huge amount of medical resources. There is an urgent need for cost-effective intervention programs for disability prevention, which could be offset against the cost for treating the disabled.

A prospective cohort study on National Health Insurance beneficiaries in Ohsaki, Miyagi Prefecture, Japan: study design, profiles of the subjects and medical cost during the first year.

To examine the impact of health-related lifestyle upon medical care utilization and its costs, we conducted a cohort study among all National Health Insurance beneficiaries aged from 40 to 79 years living in the catchment area of Ohsaki Public Health Center, Miyagi, Japan. The baseline survey, using self-completed questionnaire regarding health-related lifestyle, was conducted between October and December 1994. Out of 54,996 eligible subjects, 52,029 (94.6%) responded and formed the cohort under study. Medical care utilization (number of outpatient visits and days of inpatient care) and the costs for each subject have been obtained from National Health Insurance Claim History files since January 1995. The baseline characteristics of health-related lifestyle and medical history at the study subjects were consistent with those at our another cohort subjects (so-called Miyagi cohort study; N = 47,605), which included all the residents aged from 40 to 64 years at 14 municipalities in Miyagi Prefecture, Japan conducted in 1990. The medical costs per capita in this cohort was quite compatible with the national average. This prospective cohort study would quantitatively demonstrate the economic impact of health-related lifestyle, thus would lead us to better provision of cost-effective preventive health services.