Reproducibility of 24-hour dietary recall for vitamin intakes by middle-aged Japanese men and women

OBJECTIVE

To examine the reproducibility of 24-hour dietary recall for estimating dietary vitamin intakes by middle-aged Japanese men and women.

METHODS AND RESULTS

The subjects were 132 men and 130 women aged 40-69 years, selected from participants in cardiovascular risk surveys conducted in 4 communities. The reproducibility of the 24-hour dietary recall was tested by comparing nutrient and food intake for two recalls conducted on the same season 1 year apart, designated as recalls 1 and 2. Differences in mean values between two recalls were tested using analysis of variance, and Spearman rank correlation coefficients for the two recalls were calculated for nutrient and food intakes. Mean values of energy and vitamins for both sexes were generally similar for the two recalls. The reproducibility of recall by men was high for vitamin B2, folate, pantothenic acid, and vitamin C and by women for vitamin B2, moderate by men for vitamins A, E, K, B1, B6 and niacin, and by women for vitamins A, E, K, B1, B6 and niacin, folate, pantothenic acid and vitamin C, and low by both men and women for vitamins D and B12. The reproducibility during 1985-1999 was generally lower than that of 1973-1984, but that for folate, pantothenic acid and vitamin C remained to be moderate in 1984-1999.

CONCLUSIONS

Although the reproducibility of 24-hour dietary recall varies among vitamins, moderate and sustained reproducibility was observed for folate, vitamin C and pantothenic acid.

Nocturnal intermittent hypoxia and metabolic syndrome; the effect of being overweight: the CIRCS study

AIM

We investigated whether nocturnal intermittent hypoxia, a surrogate marker for obstructive sleep apnea, is associated with metabolic syndrome and its components among Japanese.

METHODS

We examined 1,710 male and 2,896 female community-dwelling Japanese aged 40 to 69, who participated in annual cardiovascular examinations and investigations of sleep. Nocturnal intermittent hypoxia was estimated based on a 3% oxygen desaturation index measured with pulse-oximetry during sleep. No, mild and moderate-to-severe nocturnal intermittent hypoxia were defined by <5, 5 to <15 and >or=15 events/hour, respectively. Metabolic syndrome was defined by modified criteria of the Adult Treatment Panel III guidelines.

RESULTS

Compared with no nocturnal intermittent hypoxia, the multivariable odds ratio of metabolic syndrome was 1.9 (95% confidence interval: 1.6-2.4) for mild and 3.2 (2.2-4.7) for moderate-to-severe nocturnal intermittent hypoxia among men; 2.6 (2.1-3.4) and 5.8 (3.4-9.8) among women, respectively. When stratified by overweight status (body mass index >or=25 kg/m(2)), the multivariable odds ratio of two or more metabolic risk factors (other than overweight) associated with moderate-to-severe nocturnal intermittent hypoxia was 1.9 (1.2-3.1) among non-overweight subjects and 1.4 (0.9-2.1) among overweight subjects (p for interaction=0.002).

CONCLUSIONS

Nocturnal intermittent hypoxia was associated with the accumulation of metabolic risk factors, especially among non-overweight individuals.

Measurement performance of reagent manufacturers by Centers for Disease Control and Prevention/Cholesterol Reference Method Laboratory Network lipid standardization specified for metabolic syndrome-focused health checkups program in Japan

AIM

This study was designed to clarify the current measurement performance of 7 reagent manufacturers for high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol (LDLC) and triglycerides (TG) specified for the metabolic syndrome (MetS)-focused health checkups program in Japan.

METHODS

Twenty HDLC, 21 LDLC and 9 TG analytical reagent/instrument/calibrator systems (system), and combinations of reagent lots, instrument models and calibrator lots, underwent Centers for Disease Control and Prevention (CDC)/Cholesterol Reference Method Laboratory Network (CRMLN) lipid standardization. Eighty and 100% systems were requested to achieve an accuracy of within +/-1% and +/-2% of the reference value, so that a clinical laboratory can meet the CDC criteria.

RESULTS

The CDC performance criteria of HDLC, LDLC and TG require an accuracy of within +/-5%, +/-4% and +/-5%, respectively. For HDLC, all 20 systems met the criteria. Fourteen (70.0%) and 18 (90.0%) systems were within +/-1% and +/-2%, respectively. For LDLC, 14 (66.7%) of 21 systems met the criteria, but 7 (33.3%) failed. Five (23.8%) and 17 (81.0%) systems were within +/-1% and +/-2%, respectively. For TG, 8 of 9 systems met the criteria. Two (22.2%) and 4 (44.4%) systems were within +/-1% and +/-2%, respectively. The minimum and maximum differences of a specified sample among manufacturers were 1.6 and 11.0 mg/dL for HDLC, 7.8 and 33.0 mg/dL for LDLC, and 2.8 and 27.4 mg/dL for TG, respectively.

CONCLUSION

Homogeneous HDLC methods are acceptable for MetS, but further accuracy improvement of homogeneous LDLC and TG methods will be needed because of their poor performance.

Relationship of urinary cGMP excretion with aging and menopausal status in a general population

AIM

Aging and postmenopausal women are associated with increased risks of cardiovascular disease; however, epidemiological evidence concerning the relationship of aging and the menopause with vascular biological activity is limited.

METHODS

We investigated the relationship of aging and the menopause with urinary excretion of cyclic guanosine 3',5' monophosphate (cGMP) in 1,541 Japanese men and women aged 40 to 79 years. The 24-hour urinary excretion of cGMP was measured with a (125)I-labeled cGMP radioimmunoassay and was adjusted for urinary creatinine excretion (nmol/mmol creatinine).

RESULTS

Aging was positively associated with urinary excretion of cGMP for both sexes. Postmenopausal women excreted significantly less urinary cGMP than premenopausal women after adjustment for age and other cardiovascular risk factors: 48.3+/-0.04 nmol/mmol vs. 61.5+/-0.07 nmol/mmol, p=0.006.

CONCLUSIONS

Our data suggest that cGMP-related vasodilatation is impaired in postmenopausal women.

Relations between protein intake and blood pressure in Japanese men and women: the Circulatory Risk in Communities Study (CIRCS)

BACKGROUND

An inverse association between protein intake and blood pressure has been reported in Western countries. However, the evidence is limited for Asians, whose protein sources are different from those in Western populations.

OBJECTIVES

The objective was to examine the association between protein intake and blood pressure in Japanese adults.

METHODS

We conducted a population-based, cross-sectional study of 7585 subjects (3499 men and 4086 women) from 40 to 69 y of age living in 5 communities in Japan. Dietary intakes of total, animal, and plant protein were estimated by a single 24-h dietary recall. We then examined the associations between dietary intake of those proteins and blood pressure after adjustment for age, sex, community, body mass index, antihypertensive medication use, ethanol intake, smoking, and dietary intakes of sodium, potassium, and calcium.

RESULTS

After adjustment for cardiovascular disease risk factors, a 25.5-g/d increment in total protein intake was associated with a decrease in systolic blood pressure of 1.14 mm Hg (P < 0.001) and in diastolic blood pressure of 0.65 mm Hg (P < 0.001), and a 19.9-g/d increment in animal protein intake was associated with a decrease in systolic blood pressure of 1.09 mm Hg (P < 0.001) and in diastolic blood pressure of 0.41 mm Hg (P = 0.003). A 13.1-g/d increment in plant protein intake was associated with a decrease in diastolic blood pressure of 0.57 mm Hg (P < 0.001). Further adjustment for nutritional factors weakened these associations, but the inverse associations of total protein intake with diastolic blood pressure and of animal protein intake with systolic blood pressure remained statistically significant.

CONCLUSION

Total and animal protein intakes were inversely associated with blood pressure in Japanese adults.

Trends for blood pressure and its contribution to stroke incidence in the middle-aged Japanese population: the Circulatory Risk in Communities Study (CIRCS)

BACKGROUND AND PURPOSE

Hypertension is a major risk factor for stroke. However, a substantial decrease in blood pressure levels in Japanese during the past 3 decades may have reduced contributions of hypertension to risk of stroke. The population attributable fraction, the percentage of outcomes attributable to exposure, of blood pressure for the incidence of stroke was investigated during 3 survey periods between 1963 and 1994 by means of a population-based cohort study.

METHODS

We explored 3 cohort data of residents aged 40 to 69 years in 4 Japanese communities in 1963 to 1971 (n=5439), 1975 to 1984 (n=9945), and 1985 to 1994 (n=11 788) baseline surveys. Mean follow-up period for each cohort was 10 years.

RESULTS

Higher blood pressure levels were associated with higher risk of stroke. Positive associations were also observed even within nonhypertension levels. From the first to the third cohorts, the blood pressure category with a majority of stroke incidence shifted from severe or moderate hypertension to mild hypertension. The population attributable fraction of the severe hypertension category in the first, second, and third cohorts were 20%, 14%, and 9%, respectively, and those of the moderate hypertension category were 19%, 24%, and 11%, respectively, whereas those of the mild hypertension category were 17%, 26%, and 23%, respectively. The results were similar when participants on antihypertensive medication were excluded.

CONCLUSIONS

The higher risk of stroke incidence with higher blood pressure levels even in nonhypertension categories and the shift of stroke burden from severe/moderate hypertension to mild hypertension support the early management of hypertension and primary prevention of high blood pressures for the prevention of stroke.

Establishment of long-term monitoring system for blood chemistry data by the national health and nutrition survey in Japan

AIM

We established a monitoring system for the annual follow-up of blood chemistry data obtained by the National Health and Nutrition Survey in Japan.

METHODS

Blood chemistry testing has been entrusted to SRL Inc. We used two external quality control assurance programs established by the Japan Medical Association (JMA) and by CDC/CRMLN during the previous 8-year period. Ten analytes were measured: total cholesterol, HDL cholesterol, triglycerides, urea nitrogen, uric acid, creatinine, AST (GOT), ALT (GPT), gamma-GT (gamma-GTP), and glucose. Total error (TE) was calculated from accuracy by the JMA program and precision by internal quality control of SRL. The permissible range of TE values was determined to be 50% of the evaluation limit on one side in the evaluation criteria of the College of American Pathologists (CAP). When TE fell within the permissible range, the follow-up of annual changes was considered possible.

RESULTS

Annual follow-up of blood chemistry data was considered possible for all the analytes except urea nitrogen. Based on this study, new permissible TE ranges are proposed.

CONCLUSION

We confirmed the functioning of the monitoring system for the annual follow-up of blood chemistry data obtained by the National Health and Nutrition Survey in Japan.

Relationships of Craniofacial Morphology and Body Mass Index with Sleep-Disordered Breathing in Japanese Men

OBJECTIVE/HYPOTHESIS

Obesity is an established risk factor for sleep-disordered breathing, but the impact of craniofacial morphology is uncertain. The aim of this study was to assess the impact of craniofacial morphology and body weight on sleep-disordered breathing in Japanese men.

STUDY DESIGN

A cross-sectional study.

METHODS

We measured body mass index, seven cephalometric variables, and 3% oxygen desaturation index recorded by a pulse oximeter in 313 Japanese men aged 20 to 65 years who attended a sleep clinic. We defined craniofacial score as the sums of quartile points (0-3) for distance from sella to nasion and that from hyoid bone to mandibular plane.

RESULTS

The mean value of 3% oxygen desaturation index and odds ratios of 3% oxygen desaturation index 15 or greater progressively increased with craniofacial score as well as body mass index. Multivariate odds ratios associated with craniofacial score were higher in men with body mass index 25.0 kg/m or greater (odds ratio = 4.2, 95% confidence interval [CI] = 2.1-8.6) than in men with lower body mass index (odds ratio = 1.6, 95% CI = 0.7-3.6).

CONCLUSIONS

Our results imply the importance of cephalometric assessment in overweight patients.

Effects of habitual alcohol intake on ambulatory blood pressure, heart rate, and its variability among Japanese men

We sought to examine effects of habitual alcohol intake on ambulatory blood pressure (BP), heart rate (HR), and HR variability among Japanese men. Subjects were 539 men aged 35 to 65 years from rural and urban communities. Ambulatory BP and HR were monitored with an automated, portable, noninvasive multibiomedical recorder. Power spectral analysis of the RR intervals on the ECG was performed every 5 minutes. Compared with nondrinkers, moderate drinkers (alcohol intake 23 to 45 g/d) and heavy drinkers (alcohol intake >or=46 g/d) showed higher age- and field-adjusted mean values of systolic and diastolic BPs during the morning and while awake, but there were no differences in BPs over 24-hour periods and while asleep among the alcohol intake categories. Alcohol intake was positively associated with mean values of sleep-morning differences and daytime variability in BPs, HRs while awake and asleep, and low frequency:high frequency ratio while asleep. The results were virtually unchanged after adjustment for body mass index, smoking, and diabetes mellitus. Compared with the nondrinkers, age- and field-adjusted odds ratios of the morning BP surge (excess elevation of BP in the morning: morning systolic BP minus sleep systolic BP >or=37 mm Hg) for light (alcohol intake 0 to 22 g/d), moderate, and heavy drinkers were 0.96 (95% CI: 0.34 to 2.78), 1.68 (95% CI: 0.64 to 4.38), and 2.73 (95% CI: 1.12 to 6.67), respectively. Habitual alcohol intake was associated with increased BP in the morning, HR while awake and asleep, and sympathetic activity while asleep, which may explain some of the mechanisms of the relationship between heavy alcohol intake and risk of cardiovascular diseases.

Associations of sleep-disordered breathing with excessive daytime sleepiness and blood pressure in Japanese women

Sleep-disordered breathing (SDB) is a recognized risk factor for excessive daytime sleepiness (EDS) and hypertension, but evidence of this association in Asian women is limited. We conducted a cross-sectional study of 3,568 women aged 30-69 years living in three Japanese communities. The 3% oxygen desaturation index (ODI) was selected as the indicator of SDB, and blood oxygen fall was estimated by overnight pulse oximetry. The prevalence of SDB was 20.2% for 3% ODI>or=5, 6.4% for 3% ODI>or=10, and 2.8% for 3% ODI>or=15 among Japanese women aged 30-69 years. The 3% ODI was positively associated with the prevalence of self-reported EDS and mean values of systolic and diastolic blood pressure levels. The multivariate odds ratios for 3% ODI of 5-9, 10-14, and >or=15 in reference to 3% ODI<5 were 1.9 (1.2-3.0), 2.2 (1.0-4.6), and 1.8 (0.7-4.4) (p for trend=0.01), respectively, for EDS and 1.1 (0.9-1.4), 1.2 (0.8-1.8), and 2.2 (1.4-3.4) (p for trend<0.001), respectively, for hypertension. The severity of SDB was significantly associated with EDS and hypertension among Japanese women.

Caregiver burden for impaired elderly Japanese with prevalent stroke and dementia under long-term care insurance system

BACKGROUND

Limited data are available on caregiver burden for stroke and dementia patients. We examined the associations of prevalent stroke and dementia with family caregiver burden in Japanese general populations.

METHODS

A total of 916 Japanese home caregivers, whose family members were covered by long-term care insurance, responded to the caregiver burden questionnaire. The questionnaire included the caregiver's age, sex and employment status, the patient-caregiver relationship, the patient's history of stroke, symptoms of dementia, care levels under long-term care insurance and the Zarit Caregiver Burden Interview.

RESULTS

The mean total score from the Zarit Caregiver Burden Interview was 12% higher in patients with stroke than in those without (p = 0.02) and 40% higher in those with dementia than in those without (p < 0.001). Compared with nonstroke patients without dementia, the mean total score was 21% higher in stroke patients without dementia (p = 0.01), 49% higher in nonstroke patients with dementia (p < 0.001) and 55% higher in stroke patients with dementia (p < 0.001). After adjustment for the caregiver's age, sex and employment status, the patient-caregiver relationship, and the patient's care level and community, the higher scores remained statistically significant for nonstroke patients with dementia and for stroke patients with dementia but not for stroke patients without dementia.

CONCLUSIONS

Prevalent stroke and, more strongly, dementia were associated with increased family caregiver burden. Among patients with dementia, the presence of stroke did not enhance caregiver burden further.

High sodium intake strengthens the association of ACE I/D polymorphism with blood pressure in a community

BACKGROUND

Limited evidence is available on a gene-environment interaction of angiotensin-converting enzyme (ACE) gene I/D polymorphism and high blood pressure (BP) with salt intake among general populations. We hypothesized that persons with the I allele of the ACE gene have elevated BP levels in response to a higher sodium intake, and thus the association of ACE I/D polymorphism with BP levels was stronger among persons with a higher sodium intake than those with a lower sodium intake.

METHODS

We conducted a population-based cross-sectional study of 2823 men and women aged 30 to 74 years in a Japanese rural community to examine the association of the ACE I/D polymorphism with BP levels stratified by salt intake, as estimated by 24-h urine collection and dietary questionnaire. Polymorphism of the ACE I/D was detected by an allele-specific polymerase chain reaction.

RESULTS

There was no significant difference in BP levels among DD, ID, and II groups for either sex or total samples. However, mean difference in diastolic BP levels for II versus DD groups was +3.0 mm Hg (P = .003) among persons with higher sodium excretion, +1.8 mm Hg (P = .04) among those with higher present sodium intake score, and +1.7 mm Hg (P = .06) among those with higher past sodium intake score.

CONCLUSIONS

A high sodium intake strengthens the association of ACE I/D polymorphism with BP levels in community-based samples.

Metabolic Syndrome and the Risk of Ischemic Heart Disease and Stroke Among Japanese Men and Women

Background and Purpose— Limited evidence was available on the metabolic syndrome and risk of cardiovascular disease in Asia. The purpose of this study is to examine the association of the metabolic syndrome and risk of ischemic cardiovascular disease in Japanese men and women.

Methods— We conducted an 18-year prospective study of 9087 Japanese people aged 40 to 69 years (3595 men and 5492 women), initially free of ischemic heart disease or stroke. During follow-up, there were 116 (74 men and 42 women) cases of ischemic heart disease and 256 (144 men and 112 women) ischemic strokes. Metabolic syndrome was defined by the modified criteria of the National Cholesterol Education Program Adult Treatment Panel III (NCEP/ATPIII), with the presence of ≥3 of the following factors: (1) serum triglycerides ≥1.69 mmol/L (150 mg/dL); (2) HDL-cholesterol <1.03 mmol/L (40 mg/dL) for men and <1.29 mmol/L (50 mg/dL) for women; (3) glucose ≥6.11 mmol/L (110 mg/dL) fasting or ≥7.77 mmol/L (140 mg/dL) nonfasting, or on treatment; (4) blood pressure ≥130/85 mm Hg or medication use, and (5) body mass index ≥25.0 kg/m 2 .

Results— For both sexes, high blood pressure, high triglycerides and low HDL cholesterol were associated with increased risks of ischemic heart disease or stroke after adjustment for cardiovascular risk factors. A dose-response relationship was found between the number of metabolic risk factors and incidence of these cardiovascular end points. The multivariable hazard ratio (95% CI) associated with metabolic syndrome was 2.4 (1.4 to 4.0) in men and 2.3 (1.2 to 4.3) in women for ischemic heart disease, and 2.0 (1.3 to 3.1) and 1.5 (1.0 to 2.3), respectively, for ischemic stroke. The contribution of metabolic syndrome to the risks was independent of serum total cholesterol levels but stronger among smokers.

Conclusions— The metabolic syndrome is a major determinant of ischemic cardiovascular disease among middle-aged Japanese men and women, in particular among smokers.