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

Combined Associations of Body Mass Index and Metabolic Health Status on Medical and Dental Care Days and Costs in Japanese Male Employees: A 4-Year Follow-Up Study

BACKGROUND

The combined associations of body mass index (BMI) levels and metabolic dysfunction with medical and dental care utilizations is unclear.

METHODS

A 4-year follow-up study was performed in 16,386 Japanese male employees (mean age 48.2 [standard deviation, 11.0] years) without a history of cardiovascular disease (CVD), cancer, or renal failure. They were classified into eight phenotypes based on four BMI levels (underweight, <18.5; normal weight, 18.5-24.9; overweight, 25.0-29.9; and obese, ≥30.0 kg/m²) and the presence or absence of ≥2 of 4 metabolic abnormalities: high blood pressure, high triglycerides, low high-density-lipoprotein cholesterol, and high blood sugar. Based on their health insurance claims data, we compared medical and dental care days and costs among the eight different BMI/metabolic phenotypes during 2010-2013.

RESULTS

The combinations of BMI levels and metabolic status were significantly associated with the adjusted mean and median medical outpatient days and costs and the median dental outpatient days and costs. The obese/unhealthy subjects had the highest medical outpatient days and costs, and the underweight/unhealthy subjects had the highest dental outpatient days and costs. The underweight/unhealthy subjects also had the highest medical inpatient days and hospitalization rates of CVD, and had higher medical costs compared with the obese/healthy subjects. The differences in median medical costs between healthy and unhealthy phenotypes were larger year by year across all BMI levels.

CONCLUSIONS

Identification of obesity phenotypes using both BMI levels (including the underweight level) and metabolic status may more precisely predict healthcare days and costs compared with either BMI or metabolic status alone.

An Investigation of Factors Influencing High Usage of Medical and Long-Term Care Services in an Aging Society in Japan

Medical and long-term care costs are increasing all over the world. In this study, we investigated the characteristics of groups with high cost of medical and long-term care to define targets for curbing social security costs. As a result, for the population covered by the National Health Insurance, a large portion of medical costs were incurred for mental disorders, malignant neoplasms, and lifestyle-related diseases. For those covered by the Late Elderly Health Insurance System, most medical costs were incurred for lifestyle-related diseases, femoral fractures, neurological diseases, mental disorders, pneumonia, malignant neoplasms, and Alzheimer’s disease. From multiple regression analysis, the hospitalization days, use of advanced medical treatment, outpatient days, and high long-term care level influenced the increased costs. On the other hand, disease characteristics had only a very low effect. These findings suggest that the target population has complex medical and long-term care needs because they have multiple diseases.

Impact and attribute of each obesity-related cardiovascular risk factor in combination with abdominal obesity on total health expenditures in adult Japanese National Health insurance beneficiaries: The Ibaraki Prefectural health study

Background

The aim of this study was to examine the attribution of each cardiovascular risk factor in combination with abdominal obesity (AO) on Japanese health expenditures.

Methods

The health insurance claims of 43,469 National Health Insurance beneficiaries aged 40–75 years in Ibaraki, Japan, from the second cohort of the Ibaraki Prefectural Health Study were followed-up from 2009 through 2013. Multivariable health expenditure ratios (HERs) of diabetes mellitus (DM), high low-density lipoprotein cholesterol (LDL-C), low high-density lipoprotein cholesterol (HDL-C), and hypertension with and without AO were calculated with reference to no risk factors using a Tweedie regression model.

Results

Without AO, HERs were 1.58 for DM, 1.06 for high LDL-C, 1.27 for low HDL-C, and 1.31 for hypertension (all P < 0.05). With AO, HERs were 1.15 for AO, 1.42 for DM, 1.03 for high LDL-C, 1.11 for low HDL-C, and 1.26 for hypertension (all P < 0.05, except high LDL-C). Without AO, population attributable fractions (PAFs) were 2.8% for DM, 0.8% for high LDL-C, 0.7% for low HDL-C, and 6.5% for hypertension. With AO, PAFs were 1.0% for AO, 2.3% for DM, 0.4% for low HDL-C, and 5.0% for hypertension.

Conclusions

Of the obesity-related cardiovascular risk factors, hypertension, independent of AO, appears to impose the greatest burden on Japanese health expenditures.

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The highest population attributable fraction was for hypertension without obesity.

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The total population attributable fraction of hypertension was 11.7%.

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Hypertension could impose the greatest attribute on Japanese health expenditures.

Impact of cardiovascular risk factors on medical expenditure: evidence from epidemiological studies analysing data on health checkups and medical insurance

Concerns have increasingly been raised about the medical economic burden in Japan, of which approximately 20% is attributable to cardiovascular disease, including coronary heart disease and stroke. Because the management of risk factors is essential for the prevention of cardiovascular disease, it is important to understand the relationship between cardiovascular risk factors and medical expenditure in the Japanese population. However, only a few Japanese epidemiological studies analysing data on health checkups and medical insurance have provided evidence on this topic. Patients with cardiovascular risk factors, including obesity, hypertension, and diabetes, may incur medical expenditures through treatment of the risk factors themselves and through procedures for associated diseases that usually require hospitalization and sometimes result in death. Untreated risk factors may cause medical expenditure surges, mainly due to long-term hospitalization, more often than risk factors preventively treated by medication. On an individual patient level, medical expenditures increase with the number of concomitant cardiovascular risk factors. For single risk factors, personal medical expenditure may increase with the severity of that factor. However, on a population level, the medical economic burden attributable to cardiovascular risk factors results largely from a single, particularly prevalent risk factor, especially from mildly-to-moderately abnormal levels of the factor. Therefore, cardiovascular risk factors require management on the basis of both a cost-effective strategy of treating high-risk patients and a population strategy for reducing both the ill health and medical economic burdens that result from cardiovascular disease.

Serum brain-derived neurotrophic factor levels are associated with dyssomnia in females, but not males, among Japanese workers

STUDY OBJECTIVES

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family of growth factors that promote the growth and survival of neurons. Recent evidence suggests that BDNF is a sleep regulatory substance that contributes to sleep behavior. However, no studies have examined the association between the serum BDNF levels and dyssomnia. The present study was conducted to clarify the association between the serum BDNF levels and dyssomnia.

METHODS

A total of 344 workers (age: 40.1 ± 10.5 years, male: 204, female: 140) were included in the study. The serum BDNF levels were categorized into tertiles according to sex.

RESULTS

The prevalence of dyssomnia was 35.1% in males and 30.0% in females. In the females, the BDNF levels were found to be negatively associated with dyssomnia after adjusting for age, body mass index, hypertension, dyslipidemia, hyperglycemia, depression, smoking, alcohol intake, and regular exercise. Compared with the females in the high BDNF group, the multivariate odds ratio (95% CI) of dyssomnia was 2.08 (0.62-6.98) in females in the moderate BDNF group and 8.41 (2.05-27.14) in females in the low BDNF group. No such relationships were found in the males.

CONCLUSIONS

The serum BDNF levels are associated with dyssomnia in Japanese female, but not male, workers.

The clustering of cardiovascular disease risk factors and their impacts on annual medical expenditure in Japan: community-based cost analysis using Gamma regression models

OBJECTIVE

The clustering of cardiovascular disease (CVD) risk factors is a serious threat for increasing medical expenses. The age-specific proportion and distribution of medical expenditure attributable to CVD risk factors, especially focused on the elderly, is thus indispensable for formulating public health policy given the extent of the ageing population in developed countries.

DESIGN

Cost analysis using individuals' medical expenses and their corresponding health examination measures.

SETTING

Shiga prefecture, Japan, from April 2000 to March 2006.

PARTICIPANTS

33 213 participants aged 40 years and over.

MAIN OUTCOME MEASURES

Mean medical expenditure per year.

METHODS

Gamma regression models were applied to examine how the number of CVD risk factors affects mean medical expenditure. The four CVD risk factors analysed in this study were defined as follows: hypertension (systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg), hypercholesterolaemia (serum total cholesterol ≥240 mg/dl), high blood glucose (casual blood glucose ≥200 mg/dl) and smoking (current smoker). Sex-specific and age-specific investigations were carried out on the elderly (aged 65 and over) and non-elderly (aged 40-64) populations.

RESULTS

The mean medical expenditure (per year) for the no CVD risk-factor group was only 110 000 yen at age 50 (men, 110 708 yen; women, 107 109 yen), but this expenditure was 6-7 times higher for 80-year-olds who have three or four CVD risk factors (men, 603 351 yen; women, 765 673 yen). The total overspend (excess fraction) was larger for the non-elderly (men, 15.4%; women, 11.1%) than that for the elderly (men, 0.1%; women, 5.2%) and largely driven by people with one or two CVD risk factors, except for elderly men.

CONCLUSIONS

The age-specific proportion and distribution of medical expenditure attributable to CVD risk factors showed that a high-risk approach for the elderly and a population approach for the majority are both necessary to reduce total medical expenditure in Japan.

A comparison of disease-specific medical expenditures in Japan using the principal diagnosis method and the proportional distribution method

BACKGROUND

There are technical limitations to handling all the information mentioned in health insurance claims (HICs) in Japan. Therefore, conventional methods for estimating disease-specific medical expenditures assume that all medical care expenditures in a given HIC are spent on only one principal diagnosis even when the HIC contains multiple diagnoses.

OBJECTIVES

To estimate the disease-specific medical expenditures that consider all diagnosis on a given HIC.

METHODS

Data were obtained from 169 622 outpatient HICs in May 2006 from health insurance provided by the employer. We compared the estimated disease-specific medical expenditures of the conventional method with a proportional distribution method (PDM), which considers all diagnoses on the HICs.

RESULTS

For diabetes mellitus and other diseases of the digestive system, the proportion of principal diagnoses among total diagnoses was 52.4% (4849/9251) and 19.6% (2614/13331), respectively. In addition, the ratio of the estimated disease-specific medical expenditures between the conventional method and the PDM method was 1.49 for diabetes mellitus and 0.64 for other diseases of the digestive system. The estimation of disease-specific medical expenditures using the conventional method may therefore have overestimated the expenditures on the disease category typically selected as the principal diagnosis and underestimated the expenditures on the disease category less likely to be selected as the principal diagnosis.

CONCLUSIONS

The conventional method for estimation of disease-specific medical expenditures should be improved by utilizing all the diagnoses information on HICs.

[Effect of cardiovascular risk factors on individual and population medical expenditures: a 10-year cohort study of 4,535 National Health Insurance beneficiaries in Shiga]

A 10-year follow-up cohort study of 4,535 National Health Insurance beneficiaries aged 40 to 69 years in Shiga was performed as part of a research project conducted by the Health Promotion Research Committee of the Shiga National Health Insurance Organizations in 2002. The relationship between cardiovascular risk factors and medical expenditures during the 10-year study period has been examined in this cohort. For example, there was a positively graded correlation between blood pressure and individual total medical expenditures per month. The odds ratio for cumulative hospitalization and hazard ratio for all-cause mortality in severe hypertensives were also higher than those in normotensives. However, from the viewpoint of the entire population, the excess medical expenditures attributable to hypertension within the total medical expenditures were higher for mild-to-moderate hypertensives than for severe hypertensives. On the other hand, although individual medical expenditures per month were 1.7-fold higher for participants with 2 or 3 risk factors and obesity, which was broadly equivalent to metabolic syndrome, than for those without these factors, the excess medical expenditures determined by risk clustering within the total medical expenditures were higher in normal-weight people than in obese people because of the higher prevalence of normal weight. These findings suggest that high-risk individuals are a good target of a high-risk approach, such as intensive health guidance, from the viewpoint of medical expenditures. However, another approach for the majority with a low-to-moderate cardiovascular risk should be considered, because they account for a greater proportion of the excess medical expenditures. Another way to solve this problem may be a population approach with an effective method of providing information to citizens.

Medical expenditures of men with hypertension and/or a smoking habit: a 10-year follow-up study of National Health Insurance in Shiga, Japan

Hypertension and smoking are major causes of disability and death, especially in the Asia-Pacific region, where there is a high prevalence of a combination of these two risk factors. We attempted to measure the medical expenditures of a Japanese male population with hypertension and/or a smoking habit over a 10-year period of follow-up. A cohort study was conducted that investigated the medical expenditures due to a smoking habit and/or hypertension during the decade of the 1990s using existing data on physical status and medical expenditures. The participants included 1708 community-dwelling Japanese men, aged 40-69 years, who were classified into the following four categories: 'neither smoking habit nor hypertension', 'smoking habit alone', 'hypertension alone' or 'both smoking habit and hypertension.' Hypertension was defined as a systolic blood pressure of > or =140 mm Hg, a diastolic blood pressure of > or =90 mm Hg or taking antihypertensive medications. In the study cohort, 24.9% had both a smoking habit and hypertension. During the 10-year follow-up period, participants with a smoking habit alone (18,444 Japanese yen per month), those with hypertension alone (21,252 yen per month) and those with both a smoking habit and hypertension (31,037 yen per month) had increased personal medical expenditures compared with those without a smoking habit and hypertension (17,418 yen per month). Similar differences were observed even after adjustment for other confounding factors (P<0.01). Japanese men with both a smoking habit and hypertension incurred higher medical expenditures compared with those without a smoking habit, hypertension or their combination.

Relationship between 5-year decline in instrumental activity of daily living and accumulation of cardiovascular risk factors: NIPPON DATA90

AIM

To clarify the relationship between the accumulation of cardiovascular risk factors and the 5-year decline in instrumental activity of daily living (IADL) among a cohort representative of the Japanese population aged 65 years and over.

METHODS

An IADL survey was performed by public health centers throughout Japan. Study subjects were elderly men and women living in districts under the jurisdiction of collaborating health centers. Subjects were invited to participate in the IADL survey assessed by the Tokyo Metropolitan Institute of Gerontology (TMIG) Index of Competence twice in 1995 and in 2000; 1222 participants were eligible for the analysis. The relationship between the number of cardiovascular risk factors, such as hypertension, hypercholesterolemia, hypertriglycemia, low serum high-density lipoprotein cholesterol, diabetes, obesity and smoking, at baseline and the 5-year difference in IADL scores was examined by linear regression analysis and logistic regression analysis.

RESULTS

Decrease in IADL scores was larger in those with cardiovascular risk factors than in those without. The multivariable odds ratio (OR) for decreased IADL after adding one CVD risk factor was 1.16 (95% confidence interval (CI), 1.04-1.29) after adjusting for age, sex, alcohol consumption and TMIG score at baseline. Among participants who were regarded as physically independent with respect to basic ADL in the baseline survey, the odds ratio was also similar and significant.

CONCLUSION

Preventive interventions directed against cardiovascular risk factors, especially against their accumulation, may contribute to maintaining IADL in the Japanese elderly.

Effect of chronic kidney disease on individual and population medical expenditures in the Japanese population

Chronic kidney disease (CKD) is associated with increased risk of cardiovascular disease (CVD), and may also lead to an increase in medical expenditures. The effect of CKD on individual and population medical expenditures was examined in a Japanese cohort study. The participants included 4026 Japanese National Health Insurance beneficiaries aged 40-74 years living in one city, who had no history of major CVD. They were classified into three categories according to their glomerular filtration rate (GFR) at the baseline survey, and their total medical expenditures were followed-up for 3 years. The arithmetic and geometric means of the cumulative medical expenditures were calculated for each category. The geometric mean was also expressed after adjusting for several confounding factors using analysis of covariance. The CKD-related medical expenditures attributable to the participants with mild (60 < or = GFR < 90) or moderate (30 < or = GFR < 60) kidney dysfunction were compared with those of participants with normal (GFR > or = 90) kidney function. There was a negative correlation between the GFR category and the arithmetic and geometric means of personal medical expenditures (adjusted geometric mean: GFR > or = 90, 167,879 yen; 60 < or = GFR < 90, 210,660 yen; and 30 < or = GFR < 60, 330,050 yen). The CKD-related medical expenditures accounted for 11.5 and 6.5% of the total medical expenditures for the participants with mild and moderate kidney dysfunction, respectively. The prevention of mild CKD is very important for containing medical expenditures. Appropriate strategies, such as regular creatinine measurement, are needed for early detection of CKD.

Cardiac adiposity and global cardiometabolic risk: new concept and clinical implication

The obesity epidemic is a global public health concern that increases the likelihood of morbidity and mortality of metabolic and cardiovascular disease (CVD), and threatens to reduce life expectancy around the world. The concept of the metabolic syndrome (MetS) takes into account the essential role that visceral fat plays in the development of metabolic and CVDs, and indicates how waist circumference measurement aids patient identification in the clinical setting. However, MetS cannot be used to assess global CVD risk and is, at best, another modifiable risk factor. Thus, the global cardiometabolic risk (ie, global risk of CVD resulting from traditional risk factors combined with the additional contribution of MetS) should be considered individually. The contribution of abdominal obesity to global cardiometabolic risk is reviewed and also discussed are potential underlying mechanisms including adipocytokine, insulin resistance, lipotoxicity and ectopic fat deposition in the heart components: (1) circulatory and locally recruited fat, (2) intra-and extra-myocellular fat, (3) perivascular fat, and (4) pericardial fat.

Japan Arteriosclerosis Longitudinal Study-Existing Cohorts Combine (JALS-ECC): rationale, design, and population characteristics

BACKGROUND

The Japan Arteriosclerosis Longitudinal Study-Existing Cohorts Combine (JALS-ECC) is a pooled study based on individual participant data from existing prospective cohort studies in Japan. Its purpose was to consider associations between risk factors and cardiovascular disease (CVD) outcomes, as well as differences between subgroups, defined by age, gender or geographical region, which could not be detected in the smaller samples.

METHODS AND RESULTS

Individual records for 66,691 participants in 21 cohort studies were pooled, accounting for a total of 575,628 person-years. From this data, there were 409 deaths attributed to stroke and 169 deaths attributed to coronary heart disease (CHD). Total stroke and CHD events were 1,478 and 178, respectively. Of the 1,424 total stroke events with a reported stroke subtype, 975 were classified as ischemic, 267 as hemorrhagic, and 178 as subarachnoid hemorrhage.

CONCLUSION

The JALS-ECC collected data from existing cohort studies covering a diverse Japanese population, which has provided information about the effects of modifiable factors on the risks of the CVD. Such information should provide a reliable basis for establishing prevention strategies.