Biomedical subjects

Akira Okayama

Publications and source records attributed to Akira Okayama.

At least 37 records · Page 2Linked to original sources

PubMed2006

Chronic kidney disease is a risk factor for cardiovascular death in a community-based population in Japan: NIPPON DATA90.

BACKGROUND: Chronic kidney disease (CKD) has been identified as a risk factor for cardiovascular disease (CVD). METHODS AND RESULTS: The risk of cardiovascular death was evaluated in a large cohort of participants selected randomly from the overall Japanese population. Participants (mean age, 52.4 years) free of previous CVD were followed up for 10 years. Glomerular filtration rate (GFR) was estimated using the abbreviated equation developed at the Cleveland Clinic laboratory for the Modification of Diet in Renal Disease study. Of the 7,316 participants, 6.7% had CKD with a GFR<60 at baseline. Even after adjustment for other risk factors, the presence of CKD conferred an increased risk of cardiovascular death with a hazard ratio of 1.20 (95% confidence interval, 0.82-1.76). Furthermore, a negative, graded correlation between GFR and risk of cardiovascular death was observed: 1.09 (0.72-1.64) for a 60 or=90). The proportion of excess cardiovascular death due to CKD was 1.3%. CONCLUSION: CKD was an independent risk factor for cardiovascular death in a community-dwelling Japanese population.

Adult↗

PubMed2006

Combined cardiovascular risk factors and outcome: NIPPON DATA80, 1980-1994.

BACKGROUND: To examine the prognostic significance of the high-risk group with combined cardiovascular risk factors in the Japanese, we analyzed the relationship between the high-risk group with combined risks and coronary heart disease (CHD) and stroke mortality using the NIPPON DATA80 database. METHODS AND RESULTS: At baseline in 1980, those of age>or=30 years were randomly selected and 4,144 men and 5,318 women without CHD and/or stroke at baseline were followed for 14 years. The cutoff values for risk components obtained heuristically by Cox analysis were hypertension (systolic>or=130, or diastolic>or=85 mmHg, or on antihypertensive drugs), hypercholesterolemia (total cholesterol>or=200 mg/dl), hyperglycemia (>or=130 mg/dl, or self-reported diabetes) and obesity (body mass index>or=27 kg/m2). Subjects were divided into 3 groups (0, 1-2 and 3-4 risks). Compared with those men in the risk 0 group, the hazard ratios in men in the risk 3-4 for CHD mortality was 8.04 (95% confidence interval: 1.03-62.6), and the stroke mortality was 5.06 (1.53-16.7). In women, no statistically significant difference was found due to a lesser number of events. CONCLUSION: The high-risk group with combined risk factors is important risk for Japanese men.

Adult↗

PubMed2006

Genetic variations of HSD11B2 in hypertensive patients and in the general population, six rare missense/frameshift mutations.

Mutations in the gene encoding 11beta-hydroxysteroid dehydrogenase type 2, HSD11B2, cause a rare monogenic juvenile hypertensive syndrome called apparent mineralocorticoid excess (AME). In AME, defective HSD11B2 enzyme activity results in overstimulation of the mineralocorticoid receptor (MR) by cortisol, causing sodium retention, hypokalemia, and salt-dependent hypertension. Here, we have studied whether genetic variations in HDS11B2 are implicated in essential hypertension in Japanese hypertensives and the general population. By sequencing the entire coding region and the promoter region of HDS11B2 in 953 Japanese hypertensives, we identified five missense mutations in 11 patients (L14F, n = 5; R74H, n = 1; R147H, n = 3; T156I, n = 1; R335H, n = 1) and one novel frameshift mutation (4884Gdel, n = 1) in a heterozygous state, in addition to 19 genetic variations. All genetic variations identified were rare, with minor allele frequencies less than 0.005. Four of 12 patients with the missense/frameshift mutations showed renal failure. Four missense mutations, L14F, R74H, R147H, and R335H, were successfully genotyped in the general population, with a sample size of 3,655 individuals (2,175 normotensives and 1,480 hypertensives). Mutations L14F, R74H, R147H, and R335H were identified in hypertensives (n = 6, 8, 3, and 0, respectively) and normotensives (n = 8, 12, 5, and 0, respectively) with a similar frequency, suggesting that these missense mutations may not strongly affect the etiology of essential hypertension. Since the allele frequency of all of the genetic variations identified in this study was rare, an association study was not conducted. Taken together, our results indicate that missense mutations in HSD11B2 do not substantially contribute to essential hypertension in Japanese.

11-beta-Hydroxysteroid Dehydrogenase Type 2↗

PubMed2006

Electrocardiogram screening for left high R-wave predicts cardiovascular death in a Japanese community-based population: NIPPON DATA90.

Little is known about the efficacy of left ventricular hypertrophy diagnosed by electrocardiography for predicting cardiovascular disease in a general Japanese population. In a large cohort of participants selected randomly from the overall Japanese population, we attempted to evaluate the usefulness of a high amplitude R-wave (left high R-wave) on the electrocardiogram for predicting cardiovascular death. A total of 6,688 Japanese (mean age, 50.7 years old; 57% women) free of previous cardiovascular disease and use of antihypertensive agents at baseline were followed for 10 years, from 1990 to 2000. Left high R-wave on the electrocardiogram (the Minnesota Code, 3-1 or 3-3) was found in 9.4% of the 6,688 participants, in 14.6% of the 2,413 hypertensives and in 6.4% [corrected] of the 4,275 normotensives. During the follow-up period, 133 [corrected] participants died due to cardiovascular disease. After adjustment for systolic blood pressure and other risk factors, left high R-wave conferred an increased risk of cardiovascular death; the hazard ratio among all the participants was 1.88 (95% confidence interval, 1.22-2.89; p < 0.01), that among hypertensives was 1.97 (1.20-3.24; p = 0.01), and that among normotensives was 1.66 (0.69-3.98; p = 0.26). The population attributable risk percent of left high R-wave for cardiovascular death was 7.6% among all participants, 12.4% among hypertensives and 4.1% among normotensives. Left high R-wave on electrocardiogram, irrespective of the level of systolic blood pressure, was a predictive marker for cardiovascular death among community-dwelling Japanese.

Adult↗

PubMed2006

Polymorphisms in vitamin K-dependent gamma-carboxylation-related genes influence interindividual variability in plasma protein C and protein S activities in the general population.

gamma-Glutamyl carboxylation, a reaction essential for the activity of vitamin K-dependent proteins, requires the concerted actions of gamma-glutamyl carboxylase (GGCX), vitamin K 2, 3-epoxide reductase complex 1 (VKORC1), and the chaperone calumenin (CALU). We evaluated the contribution of genetic polymorphisms in VKORC1, GGCX, and CALU to interindividual variation in the activities of plasma protein C and protein S. We sequenced these 3 genes in 96 Japanese individuals and geno-typed 9 representative single-nucleotide polymorphisms in 3655 Japanese individuals representative of the general population. The mean activity of protein C in women bearing the GG genotype of GGCX 8016G>A (130.8% +/- 1.5%, n = 156) was significantly greater (P = .002) than that of individuals with either the AG (126.8% +/- 0.7%, n = 728) or the AA (125.4% +/- 0.6%, n = 881) genotype, after adjusting for confounding factors. The GGCX 8016G>A change leads to the substitution of Gin for Arg at amino acid residue 325 (Arg 325 Gln). This effect was comparable to that of a previously defined polymorphism in the protein C promoter. Mean protein S activity was influenced by the VKORC1 3730G>A and CALU 20943T>A genotypes, after adjusting for confounding factors. Thus, polymorphisms in genes involved in the vitamin K-dependent gamma-carboxylation reaction influence interindividual variation in the activities of protein C and protein S in the general population.

Aged↗

PubMed2006

Effectiveness of a low-intensity intra-worksite intervention on smoking cessation in Japanese employees: a three-year intervention trial.

To test the effectiveness of a low-intensity intervention program for smoking cessation targeting the worksite environment in employees who had a low readiness to quit, we conducted an intervention trial at six intervention and six control worksites in Japan. A total of 2,307 smokers at baseline who remained at their worksite throughout the three-year study period were analyzed (1,017 in intervention and 1,290 in control groups). The multi-component program at the worksites consisted of (1) presenting information on the harms of tobacco smoking and the benefits of cessation by posters, websites, and newsletters; (2) smoking cessation campaigns for smokers; (3) advice on designation of smoking areas; and (4) periodic site-visits of the designated smoking areas by an expert researcher. At baseline, the intervention and control groups each had high prevalence of immotive or precontemplation, that reflected low readiness to quit (71.5% and 73.2%, respectively). The smoking cessation rate, as not having smoked for the preceding six months or longer, assessed at 36 months after the baseline survey by a self-administered questionnaire was significantly higher in the intervention group than the control group (12.1%, vs. 9.4%, p=0.021). The intervention program still had a significant effect on the smoking cessation rate after multiple logistic regression analysis adjusted for sex, age, type of occupation, age of starting smoking, quit attempts in the past, number of cigarettes per day, and readiness to quit (odds ratio: 1.38, 95% confidence interval: 1.05-1.81, p=0.02). The cost per additional quitter due to the intervention was calculated to be Yen 70,080. These findings indicate that this program is effective and can be implemented in similar workplaces where the prevalence of smoking is high and smokers' readiness to cease smoking is low.

Adult↗

PubMed2006

Continuation of smoking cessation and following weight change after intervention in a healthy population with high smoking prevalence.

Smoking prevalence among males is conspicuously high in Asian countries including Japan. There are few prospective intervention studies on the duration of smoking cessation within regions with a high prevalence of smokers, such as Asia. We investigated the extent to which subjects continued abstaining from smoking after receiving smoking cessation support provided for all smokers in an occupational setting, regardless of their willingness to quit smoking. The subjects were 251 male workers who were smokers and had received a smoking cessation intervention in 1997 in an occupational setting. Smoking cessation rates and body mass index (BMI) at 10, 18, 30, 42, 54, and 66 months after the initial intervention were confirmed during annual health check-ups. Those who quit smoking following the intervention and continuously abstained from smoking throughout the study period were separately examined for BMI. After five years, 10.6% of the smokers continued smoking cessation. Of the abstainers who quit following the intervention, the abstinence rate decreased in the first and second year, but it stabilized at approximately 45% after the third year. High nicotine dependence and a self-reported lack of willingness to quit smoking did not lower long-term abstinence rates. Abstainers initially gained 1.55 BMI on average, but decreased the weight gain to 0.96 BMI over six years. Introducing smoking cessation support without nicotine replacement therapy is an effective long-term strategy in a healthy population with a high smoking prevalence. Abstainers maintain their smoking cessation if they refrain from smoking for three years.

Adult↗

PubMed2006

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.

BACKGROUND: Evidence 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. METHODS: Four 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< or =ALT<30, 30< or =ALT<40, 40< or =ALT<50 and 50< or =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. RESULTS: A 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< or =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. CONCLUSIONS: In 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.

Adult↗

PubMed2005

Association between fish consumption and all-cause and cause-specific mortality in Japan: NIPPON DATA80, 1980-99.

PURPOSE: Although high consumption of fish may be one of the contributing factors for Japanese longevity, no epidemiological study using Japanese data has tested this hypothesis. SUBJECTS AND METHODS: The relationship between fish consumption and all-cause as well as cause-specific mortality was analyzed using the database of NIPPON DATA80. At baseline in 1980, history, physical, and blood biochemical measurement and a nutritional survey by the food-frequency method were performed in randomly selected community-based subjects aged 30 years and over in Japan. After exclusion of subjects with significant comorbidities at baseline, we followed 3945 men and 4934 women for 19 years. Men and women were analyzed comprehensively. Age- and sex-adjusted and multivariate adjusted relative risk for all-cause or cause-specific mortality was calculated using a Cox proportional hazards model with delayed entry. RESULTS: During 19 years of followup, there were 1745 deaths. Subjects were divided into 5 groups according to fish consumption frequency. The multivariate Cox analyses showed that relative risks for subjects who ate fish more than twice daily compared with those of subjects who ate 1 to 2 times weekly were 0.99 (95% confidence intervals: 0.77-1.27) for all-cause, 1.26 (0.70-2.29) for stroke, 0.92 (0.20-4.23) for cerebral hemorrhage, 1.09 (0.48-2.43) for cerebral infarction, and 0.91 (0.35-2.35) for coronary heart disease mortality. CONCLUSION: Our results did not provide evidence in support of the fish hypothesis, perhaps because the majority of the Japanese subjects in the study ate fish more than the threshold level shown to be beneficial in the previous studies.

Adult↗

PubMed2005

Relation of long chain n-3 polyunsaturated fatty acid intake to serum high density lipoprotein cholesterol among Japanese men in Japan and Japanese-American men in Hawaii: the INTERLIPID study.

Epidemiologic evidence shows an inverse relationship between fish consumption and coronary heart disease (CHD) mortality. Associations between dietary intake of long chain n-3 polyunsaturated fatty acids (PUFA) and serum high density lipoprotein (HDL) cholesterol concentration are unknown. In this study, the association between n-3 PUFA (eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA)) intake and serum HDL cholesterol among Japanese men and women in Japan and Hawaii was examined. The study population consisted of Japanese ancestries from five research centers of the International Study of Macronutrients and Blood Pressure (INTERMAP) study, in Japan and Hawaii (672 men and 676 women), surveyed between 1996 and 1998. Four 24-h dietary recalls and one set of serum lipid measurements were performed. For men, n-3 PUFA intake and HDL cholesterol were higher in Japan than in Hawaii (n-3 PUFA: 1.32 g/day versus 0.47 g/day, p<0.001). For women, n-3 PUFA intake was higher in Japan than in Hawaii (p<0.001) but HDL cholesterol was not significantly different (p=0.752). After adjustment for age, body mass index, physical activity, number of cigarettes per day, alcohol intake, and hormone replacement therapy (for women), n-3 PUFA intake was positively associated with serum HDL cholesterol in men (4.6 mg/dl higher HDL cholesterol with 1%kcal higher n-3 PUFA intake, p=0.011). This association was not observed in women. This positive association of dietary n-3 PUFA with serum HDL cholesterol may partially explain the low mortality from CHD among Japanese men.

Adult↗

PubMed2005

CRP levels are elevated in smokers but unrelated to the number of cigarettes and are decreased by long-term smoking cessation in male smokers.

BACKGROUND: It is not clear whether there is a dose-response relationship between the number of cigarettes smoked per day and CRP level and whether there is a relationship between the length of smoking cessation and CRP level. METHODS: Geometric mean levels of CRP were compared in smoking status groups for 1926 men aged 40 to 69 years using analysis of covariance. RESULTS: After adjusting for several confounding factors, geometric mean levels of CRP (mg/L) were significantly different among the three smoking status groups (0.41 in non-smokers, 0.57 in current smokers, 0.48 in past smokers, P < 0.05). A linear trend was not found in the relationship between CRP level and number of cigarettes smoked per day. The mean CRP level in the long cessation (> or =5 years) group was significantly lower than that in the short cessation (<5 years) group (0.45 vs. 0.58, P < 0.05) and similar to that in the non-smokers group (0.45 vs. 0.41, NS). CONCLUSIONS: CRP levels in current smokers are elevated but unrelated to the number of cigarettes smoked per day. In past smokers, long-term smoking cessation may contribute to the reduction in risk of development of cardiovascular diseases through inflammatory mechanisms.

Adult↗

PubMed2005

Hypertension susceptibility genes on chromosome 2p24-p25 in a general Japanese population.

BACKGROUND: Genome-wide scans from Italy and China suggest a hypertension-susceptible locus between D2S2278 (nucleotides 11,245,080 - 11,245,358) and D2S168 (nucleotides 11,467,214 - 11,467,422) on chromosome 2. METHODS: We performed a large association study of polymorphisms in this region with blood pressure modulation in a Japanese general population. Forty-seven polymorphisms in 14 genes between nucleotide 8,845,292 and nucleotide 11,946,689, which contains D2S2278 and D2S168, were genotyped in 1880 individuals, 796 of whom were hypertensive and 1084 normotensive. RESULTS: Multivariate logistic regression analysis with adjustment for age, body mass index, presence of hyperlipidemia, diabetes mellitus, and current smoking and drinking revealed that one single nucleotide polymorphism (SNP), IMS-JST126186, in HPCAL1 (hippocalcin-like 1) in women and two SNPs, IMS-JST149391 and IMS-JST149390, in GREB1 (gene regulated by estrogen in breast cancer 1) in men were significantly associated with both prevalence of hypertension and blood pressure levels. To examine the role of GREB1 in more detail, we identified 38 additional genetic variations in GREB1 by direct sequencing, and eight polymorphisms were genotyped. One SNP, 45718A>G, was significantly associated with hypertension and blood pressure level in men, and this SNP was in linkage disequilibrium with a SNP present at the 3' splice site of intron 11. CONCLUSION: Our study suggests that GREB1 and HPCAL1 are candidate hypertension-susceptibility genes in the Japanese general population and supports previous studies that also identified hypertension-related loci in this narrow region.

Adult↗

PubMed2005

Genetic variations of regulator of G-protein signaling 2 in hypertensive patients and in the general population.

OBJECTIVES: Mice deficient in the regulator of G-protein signaling 2 (RGS2) exhibit a strong hypertensive phenotype. We studied whether genetic variations in RGS2 are implicated in hypertension or other phenotypes in Japanese hypertensive individuals and the general population. METHODS: We sequenced all exons of RGS2 and the promoter region in 953 and 48 hypertensive individuals, respectively. Genotyping by the TaqMan polymerase chain reaction method was performed for six missense or frameshift mutations and common single nucleotide polymorphisms in the general population, with a sample size of 1872 individuals (862 men and 1011 women). RESULTS: We identified five novel missense mutations (Q2L; n = 2, Q2R; n = 1, M5V; n = 1, R44H; n = 2, Q78H; n = 1) and one novel frameshift mutation (1925-1926insT; n = 2) in a heterozygous state, in addition to 33 variations including five common single nucleotide polymorphisms. Six missense/frameshift mutations and three common single nucleotide polymorphisms (-638A > G, 1026T > A, 1891-1892delTC) were successfully genotyped in the general population. Mutations Q2L (n = 2), M5V (n = 1), and 1925-1926insT (n = 2) were only identified in hypertensive subjects. Six out of seven individuals with the R44H mutation, which occurs in the amphipathic alpha-helical domain of RGS2, had hypertension. The results showed a significant association of two common single nucleotide polymorphisms, 1026T > A [TT versus TA + AA: odds ratio (OR) 1.33; 95% confidence interval (CI) 1.02-1.74; P = 0.035] and 1891-1892delTC (I: insertion allele, D: deletion allele, II versus ID + DD: OR 1.47; 95% CI 1.09-1.97; P = 0.012), with hypertension in women by multivariate logistic regression analysis. CONCLUSION: Our results suggest that genetic variations in RGS2 contribute partly to the hypertensive phenotype.

Aged↗

PubMed2005

FRETS-VWF73, a first fluorogenic substrate for ADAMTS13 assay.

A plasma metalloprotease, ADAMTS13, cleaves von Willebrand factor (VWF) multimers and downregulates their activity in platelet aggregation. Functional ADAMTS13 deficiency leads to the accumulation of hyperactive large VWF multimers, inducing a life-threatening disease, thrombotic thrombocytopenic purpura (TTP). Although measuring ADAMTS13 activity is important in TTP diagnosis, existing methods require time and skill. Here, we report a fluorescence resonance energy transfer (FRET) assay for ADAMTS13 activity. We developed a synthetic 73-amino-acid peptide, FRETS-VWF73. Cleavage of this substrate between two modified residues relieves the fluorescence quenching in the intact peptide. Incubation of FRETS-VWF73 with normal human plasma quantitatively increased fluorescence over time, while ADAMTS13-deficient plasma had no effect. Quantitative analysis could be achieved within a 1-h period using a 96-well format in commercial plate readers with common filters. The FRETS-VWF73 assay will be useful for the characterization of thrombotic microangiopathies like TTP and may clarify the importance of ADAMTS13 activity as a predictive marker for various thrombotic diseases.

ADAM Proteins↗

PubMed2005

Association analysis between hypertension and CYBA, CLCNKB, and KCNMB1 functional polymorphisms in the Japanese population--the Suita Study.

BACKGROUND: Reproducibility of results is important for the validity of genetic association studies. Recently, 3 functional polymorphisms, G(-930)A in CYBA, T481S in CLCNKB, and E65K in KCNMB1, were reported to be associated with blood pressure (BP) status and the aim of this study was to confirm those findings using a large cohort representing the general Japanese population. METHODS AND RESULTS: The study population consisted of 3,652 subjects recruited from the Suita study as representative of the general population in Japan. The genotypes of the 3 polymorphisms were determined by the TaqMan method. Logistic analysis indicated that the CYBA/G(-930)A polymorphism was associated with hypertension in male subjects. In the male population, the odds ratio of the GG genotype over GA + AA was 1.27 (95% confidence interval 1.01-1.57, p=0.034). Moreover, residuals of systolic and diastolic BP values were significantly higher in subjects with the GG genotype than in those with the GA or AA genotype (p=0.0007). However, such significant effects of the genotype on BP status were not observed in the female population. The significance of the CLCNKB/T481S and KCNMB1/E65K polymorphisms were not replicated in the present study. CONCLUSION: The significance of the G(-930)A polymorphism of CYBA was confirmed in the present study with adequate statistical power, which strengthens the hypothesis that this polymorphism is important in the pathogenesis of hypertension and confers susceptibility.

Aged↗

PubMed2005

Incidence of acute myocardial infarction in Takashima, Shiga, Japan.

BACKGROUND: The incidence and mortality from ischemic heart disease (IHD) in Japan seem to be among the lowest of all the industrialized countries, but there are few reliable registers of acute myocardial infarction (AMI). METHODS AND RESULTS: To assess the incidence of AMI in Takashima County, Shiga, Japan, from 1988 to 1998 and compare the data with similar registers in the world, cases of AMI or sudden death presumed from myocardial ischemia were registered. The criteria of AMI were based on the WHO MONICA Projects. The medical records of all the hospitals inside as well as outside the county, the original death records in the health center, and the ambulance records in the county were investigated and 291 cases were registered (190 males, 101 females; average age (mean +/- SD), 69.5+/-12.2). The 28-day and 24-h case fatality was 38.1% and 33.0%, respectively. Age-adjusted annual incidence of AMI per 100,000 population aged between 25 and 74 years were 58.2 for men and 18.0 for women. The incidence of AMI showed a constant trend from 1988 to 1998. CONCLUSION: The results confirmed that Japan has the lowest incidence of AMI among the industrialized countries.

Adult↗

PubMed2005

A novel missense mutation, F826Y, in the mineralocorticoid receptor gene in Japanese hypertensives: its implications for clinical phenotypes.

A gain-of-function mutation resulting in the S810L amino acid substitution in the hormone-binding domain of the mineralocorticoid receptor (MR, locus symbol NR3C2) is responsible for early-onset hypertension that is exacerbated in pregnancy. The objective of this study was to test whether other types of missense mutations in the hormone-binding domain could be implicated in hypertension in Japanese. Here, we screened 942 Japanese patients with hypertension for the S810L mutation in exon 6 in the MR. We did not identify the S810L mutation in our hypertensive population, indicating that S810L does not play a major role in the etiology of essential hypertension in Japanese. However, we identified a novel missense mutation, F826Y, in three patients in a heterozygous state, in addition to four single nucleotide polymorphisms, including one synonymous mutation (L809L). The F826Y mutation is present in the MR hormone-binding domain and might affect the ligand affinity. The F826Y mutation was also identified in 13 individuals (5 hypertensives and 8 normotensives) in a Japanese general population (n=3,655). The allele frequency was 0.00178. The frequencies of the F826Y mutation in the hypertensive population (3/942) and in the hypertensive group (5/ 1,480) and the normotensive group (8/2,175) in the general population were not significantly different, suggesting that this mutation does not greatly affect hypertension. Although it is unclear at present whether or not the F826Y mutation makes a substantial contribution to the mineralocorticoid receptor activity, this missense mutation may contribute, to some extent, to clinical phenotypes through its effects on MR.

Aged↗

PubMed2005

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.

Adult↗