A food frequency questionnaire for use in the Chinese population in Hong Kong: Description and examination of validity

Effects of food groups and dietary nutrients on bone loss in elderly Chinese population

OBJECTIVE

To examine the effects of food groups and dietary nutrients on bone loss in elderly Chinese population.

DESIGN

Prospective cohort study.

SETTING

A longitudinal study started at 2001 in Hong Kong.

PARTICIPANTS

1225 Chinese men and 992 women aged 65 years and over in the community.

METHODS

Daily intake of food groups and dietary nutrients at baseline was assessed by a food frequency questionnaire. Nutrient intake was adjusted for energy intake by residual method. Linear regression was used to examine the association of BMD change and food group or energy-adjusted nutrient intake with adjustment for demographic, anthropometric, lifestyle factors, and daily energy intake (for food group only).

RESULTS

Higher fish intake was associated with smaller bone loss in hip (B=-0.611, p=0.004) and femoral neck (B=-0.724, p=0.040) in men. None of the food groups were associated with bone loss in both measured sites in women. For men, lower intake of protein (B=-0.012, p=0.003), phosphorus (B=-0.0008, p=0.001), sodium (B=-0.0002, p=0.023) and isoflavone (B=-1.084, p=0.030) was associated with greater BMD loss in hip, whereas lower intake of protein (B=-0.018, p=0.006) and sodium (B=-0.0004, p=0.018) was associated with greater BMD loss in femoral neck. However, these significant associations disappeared after further adjustment for energy-adjusted calcium and vitamin D intakes. None of the nutrients were associated with BMD loss in both measured sites in women.

CONCLUSIONS

Greater fish intake may help to reduce bone loss in this sample of elderly Chinese men. The significant association between various nutrients and bone loss in elderly Chinese men was likely due to the influence of dietary calcium and vitamin D intakes. The role of food groups and dietary nutrients on bone health in this sample of elderly Chinese women seems to be minimal.

Association between serum 25-hydroxyvitamin D and psychological health in older Chinese men in a cohort study

BACKGROUND

Few studies evaluated the association between vitamin D and psychological health in Chinese. This study examined these associations in Chinese older men in Hong Kong.

METHODS

Baseline serum 25-hydroxyvitamin D (25OHD), depression and cognitive function were assessed in 939 community-dwelling Chinese men aged >65. Data on depression status at 4-year follow up was available in 629 men. Data were collected for confounding factors: demographics, number of diseases, smoking, alcohol use, body mass index, physical activity, mobility limitations, dietary intake, season of blood measurement, and serum parathyroid hormone level. Multivariate logistic regression analyses were performed with adjustments for confounding factors.

RESULTS

An inverse association between serum 25OHD and baseline depression was observed. Men in the highest (>=92 nmol/L) compared with lowest (<=63 nmol/L) quartile of serum 25OHD had an adjusted odds ratio for depression of 0.46 (95% CI: 0.22-0.98, P(trend)=0.004). The association was more pronounced in low vitamin D season than in high vitamin D season. No association was observed between serum 25OHD and incident depression at 4 years. Baseline cognitive impairment was not associated with serum 25OHD in all models.

LIMITATIONS

Self-reported measure of depression and cognitive performance, the small number of incident depression at 4-year follow up and selection bias may affect the study validity.

CONCLUSIONS

Serum 25OHD was inversely associated with depression at baseline and was not linked to baseline cognitive impairment and 4-year incident depression in Chinese older men. Future studies are warranted to evaluate these associations in populations with higher prevalence of vitamin D deficiency.

Serum 25-hydroxyvitamin D, bone mineral density, and non-vertebral fracture risk in community-dwelling older men: results from Mr. Os, Hong Kong

The study examined vitamin D status in relation to bone mineral density (BMD) and fracture risk in older Chinese men. Vitamin D deficiency was uncommon in this sample. Higher serum vitamin D level was associated with higher baseline BMD, but was not associated with bone loss or fracture risk.

PURPOSE

Vitamin D status in relation to bone health and fracture risk in Asian men is unknown. This study examined how vitamin D status was associated with BMD and fracture risk in Chinese men.

METHODS

The study consisted of a cross-sectional and longitudinal design (the 4-year follow-up). Subjects included 939 and 712 men aged 65 year and older for cross-sectional analysis and longitudinal analysis, respectively. Baseline serum 25-hydroxyvitamin D (25OHD) was measured by a competitive radioimmunoassay kit. Baseline and 4-year percentage change in BMD at total hip, spine, and femoral neck was examined by dual-energy X-ray absorptiometry. Data on incident non-vertebral fractures and hip fractures in 4 years were collected. Data were collected for confounding factors: demographics, smoking, alcohol use, body mass index, physical activity, diet, season of blood measurement, and serum parathyroid hormone level. Multivariate regression analyses were performed with adjustments for confounding factors.

RESULTS

A total of 94.1% of this sample had serum 25OHD at 50 nmol/L and over. After adjustment for potential confounding factors, higher serum 25OHD level was associated with higher baseline BMD at all measured sites. No association was observed between serum 25OHD level and percentage change in BMD or risk of non-vertebral fracture or hip fracture after adjustment for confounding factors.

CONCLUSIONS

Vitamin D deficiency was not common in this sample of Chinese men. Higher serum 25OHD level was associated with higher BMD at cross-sectional level. There was no association between serum 25OHD level and bone loss or fracture risk.

Serum 25-hydroxyvitamin D and parathyroid hormone levels in relation to blood pressure in a cross-sectional study in older Chinese men

Vitamin D status, parathyroid hormone (PTH) level and their associations with blood pressure in Chinese population are unknown. This study examined these associations in older Chinese men. Blood pressure, serum 25-hydroxyvitamin D (25OHD) and PTH was measured in 939 community-dwelling Chinese men aged 65 years and older. Linear regression analyses were performed with adjustments for age, body mass index, education, season of measurement, medication use, self-reported history of stroke and Parkinson's disease, and other lifestyle factors. In either crude or adjusted models, serum 25OHD was not associated with blood pressure, whereas increasing PTH levels was associated with higher blood pressure. Men in the highest quartile of serum PTH level had a mean difference of 3.4 mm Hg and 2.8 mm Hg higher in as systolic blood pressure (SBP) and diastolic blood pressure (DBP), respectively, than men in the lowest quartile of serum PTH level (P(trend)=0.019 for SBP and <0.001 for DBP). In conclusion, the findings support an association between serum PTH and blood pressure, but not for serum 25OHD in older Chinese men whose vitamin D status is optimal. The lack of association between serum 25OHD and blood pressure may possibly because of the relatively high serum 25OHD levels of the study sample.

Energy intake and expenditure profile in chronic peritoneal dialysis patients complicated with circulatory congestion

BACKGROUND

Circulatory congestion is an adverse predictor of mortality in peritoneal dialysis (PD) patients.

OBJECTIVE

This study evaluated the nutritional status, energy intake, and expenditure profile of PD patients with and without previous circulatory congestion.

DESIGN

We conducted a cross-sectional study in 244 PD patients, of whom 92 had previous circulatory congestion. We estimated dietary energy intake by using a locally validated 7-d food-frequency questionnaire and by assessing resting energy expenditure (REE) and total energy expenditure (TEE) with indirect calorimetry and a locally validated physical activity questionnaire, respectively.

RESULTS

In comparison with those without circulatory congestion, patients with previous circulatory congestion were more malnourished by subjective global assessment (59% compared with 36%; P < 0.001), had lower handgrip strength, had lower midarm muscle circumference, had lower dietary protein (0.98 +/- 0.45 compared with 1.19 +/- 0.44 g x kg(-1) x d(-1); P < 0.001), and had lower energy intake (92.5 +/- 37.0 compared with 110.9 +/- 35.7 kJ x kg(-1) x d(-1); P < 0.001) but had higher C-reactive protein (P = 0.025) and higher REE (P < 0.001). However, no difference in TEE was noted between the 2 groups, which indicated lower activity energy expenditure among patients with previous circulatory congestion. The resulting energy balance was significantly more negative for patients with previous circulatory congestion than for those without previous circulatory congestion (P = 0.050). Furthermore, the prevalence of malnutrition increased with increasing episodes of circulatory congestion (P = 0.017).

CONCLUSIONS

Patients with previous circulatory congestion had significantly more inflammation, more muscle wasting, and higher REE but lower activity energy expenditure and energy and protein intakes in keeping with an anorexia-cachexia syndrome. The mechanisms of increased REE and reduced energy intake among patients with previous circulatory congestion warrant further investigation.

Older men with higher self-rated socioeconomic status have shorter telomeres

BACKGROUND

previous studies examining the relationship between socioeconomic status and telomere length showed conflicting results, one study finding shorter telomere length in subjects with lower socioeconomic status and one showing no relationship.

DESIGN

cross-sectional study.

SETTING

community-living elderly Chinese in Hong Kong.

OBJECTIVE

this study examines the relationship between self-rated social economic status and telomere length in Hong Kong Chinese men and women aged 65 years and over living in the community.

SUBJECTS AND METHOD

information was collected from 958 men and 978 women regarding possible confounding factors such as the presence of chronic diseases, smoking, physical activity level, dietary intake and body mass index. Telomere length was measured by quantitative PCR.

RESULT

in men only, after adjustment for age and other confounding factors, a higher ranking in community standing was associated with shorter telomere length.

CONCLUSION

men with higher self-rated socioeconomic status have shorter telomeres, possibly mediated through psychosocial rather than lifestyle factors or the presence of chronic disease. There may be cultural ethnic and age-related differences in social determinants of health.

Chinese tea consumption is associated with longer telomere length in elderly Chinese men

Environmental and lifestyle factors that affect oxidative stress and inflammation may influence telomere length (TL). There are limited data to relate the effect of dietary components on TL. The present study examined the association between food groups and TL in a sample of elderly Chinese. In a sample of 2006 Chinese (976 men and 1030 women) aged 65 years and over, TL was measured by quantitative real-time PCR and daily intake of food groups was assessed by a validated FFQ. Linear regression and analysis of covariance were used to examine the association between food group intake and TL, with adjustment for demographic and lifestyle factors. In men, only Chinese tea consumption was significantly associated with TL after adjustment for demographics and lifestyle factors (P = 0·002). Mean difference in TL for those in the highest quartile of Chinese tea consumption (>3 cups/d or >750 ml/d) as compared with those in the lowest quartile of Chinese tea consumption ( ≤ 0·28 cups/d or ≤ 70 ml/d) was 0·46 kb, corresponding to approximately a difference of 5 years of life. In women, intake of fats and oils was borderline and negatively associated with TL after adjustment for demographic and lifestyle factors (P = 0·037). In conclusion, Chinese tea consumption was positively associated with TL in elderly Chinese men.

Dietary intake, blood pressure and osteoporosis

Both hypertension and osteoporosis have common underlying nutritional aetiology, with regards to dietary cations intake. We tested the hypothesis that sodium intake reflected in urinary Na/Cr and blood pressure would be negatively associated with bone mineral density (BMD), whereas other cations may have opposite associations. Subjects were part of a study of bone health in 4000 men and women aged 65 years and over. A total of 1098 subjects who were not on antihypertensive drugs or calcium supplements and who provided urine samples were available for analysis. Logistic regression was used to examine associations between total hip and lumbar spine BMD, age, gender, body mass index (BMI), urinary Na/Cr, K/Cr, calcium and magnesium intake, systolic blood pressure and diastolic blood pressure. Total hip BMD was inversely associated with age, being female and urinary Na/Cr, and positively associated with BMI, urine K/Cr and dietary calcium intake. Lumbar spine BMD was inversely associated with being female and urinary Na/Cr, and positively associated with BMI, dietary calcium intake and SBP. We conclude that sodium intake, reflected by urinary Na/Cr, is the major factor linking blood pressure and osteoporosis as shown by the inverse relationship with BMD. The findings lend further emphasis to the health benefits of salt reduction in our population both in terms of hypertension and osteoporosis.

Relationship between grip strength and bone mineral density in healthy Hong Kong adolescents

This study evaluated the magnitude of the correlations among grip strength, bone mineral density (BMD) and bone mineral content (BMC), after controlling for weight, height, pubertal development, weight-bearing activities and calcium intake. The results lead to the conclusion that grip strength is an independent predictor of bone mass in both sexes. The relationship between muscle strength and bone mass is systemic.

INTRODUCTION

Previous studies had shown a site-specific relationship between muscle strength and bone in pubertal children. This study evaluated the magnitude of the correlations among grip strength, bone mineral density (BMD) and bone mineral content (BMC) at distant bone.

METHODS

Cross-sectional data of 169 11- to 12-year-old boys and 173 10- to 11-year-old girls came from the baseline result of a cohort study. Grip strength, BMD, BMC, weight, height, pubertal development, weight-bearing activities and calcium intake were measured. Pearson correlations and multiple regressions were used to calculate univariate and adjusted associations among grip strength and bone mass at distant bone.

RESULTS

Significant correlations were shown between grip strength and bone mass at hip, spine and whole body (boys: BMC:0.72-0.74, BMD:0.38-0.60; girls: BMC:0.71-0.72, BMD:0.44-0.63; p<0.0001). Multiple regressions with all covariates showed that about 70% and 50%, respectively, of the variations in BMC and BMD could be explained but not for whole body BMD. Grip strength was an independent predictor of bone mass, except hip BMD in boys and whole body BMD in girls. Stepwise regression showed that grip strength was a robust predictor in both sexes. Prediction models by grip strength and weight explained about 60% and 40% of the variations in BMC of different sites and in BMD of hip and spine, respectively.

CONCLUSIONS

We found that grip strength is an independent predictor of bone mass in both sexes. The relationship between muscle strength and bone mass is systemic.

Bone mineral status and its relation with dietary estimates of net endogenous acid production in Hong Kong Chinese adolescents

Diet composition influences net endogenous acid production (NEAP), which may affect bone health. No studies are available to relate dietary estimate of NEAP to bone health in Chinese adolescents. This study examined the association of dietary estimates of NEAP with bone mineral status in Hong Kong Chinese adolescents. Baseline data on 171 boys and 180 girls aged 10-12 years from the Hong Kong Adolescent Bone Health Cohort Study were presented. Weight, height, Tanner stage and dietary intakes by FFQ were collected. NEAP was estimated from diet using Frassetto's method. Bone area (BA), bone mineral content (BMC) and bone mineral apparent density (BMAD) of total hip, lumbar (L1-L4) spine and whole body were estimated by dual-energy X-ray absorptiometry (DXA). No significant association was observed between BMC or BMAD and energy-adjusted NEAP or other nutrients. BA was significantly and positively associated with BMC at all sites in both sexes. Weight was significantly and positively associated with BMC in hip and spine in both sexes. Height was negatively correlated with hip BMC for boys and whole body BMC for girls. Pubertal stage was significantly and positively associated with BMC in all sites in both sexes. Weight and height contributed most of the variability in BMAD at different sites. The results suggest that anthropometric characteristics and pubertal stage are more influential than dietary NEAP in determining bone mineral status of Hong Kong Chinese adolescents. However, the methodological weaknesses regarding the use of DXA and FFQ in the present sample require attention.

Estimated net endogenous acid production and intake of bone health-related nutrients in Hong Kong Chinese adolescents

BACKGROUND/OBJECTIVES

To examine the daily intake of bone health-related nutrients and to explore the association between diet composition and estimated net endogenous acid production (estimated NEAP) in Hong Kong Chinese adolescents.

SUBJECT/METHODS

In total, 171 boys and 180 girls aged 10-12 years of Chinese origin from nine primary schools from the Hong Kong Adolescent Bone Health Cohort Study. The study design used food frequency questionnaire. Mean daily intakes of foods and selected nutrients were estimated. Mean percentage of nutrient intake contributed by different food groups was presented. Frassetto's method was used to calculate the estimated NEAP from the diet's protein to potassium ratio.

RESULTS

There was no significant difference in the energy-adjusted intakes of most nutrients between boys and girls, except for intakes of vitamins C and D. Mean protein, sodium and potassium intakes were higher than the Chinese dietary reference intake (DRI), whereas mean intakes of magnesium, calcium and vitamin D were lower than the DRI. Boys had significantly higher estimated NEAP than girls (P=0.0051). Estimated NEAP was significantly positively correlated with meat intake and negatively associated with the consumption of fruits, vegetables, legumes, beverages and dairy products.

CONCLUSIONS

The results highlight the importance of considering whole diet quality when interpreting the effects of single nutrient or diet's net acid load on bone. The effect on high protein intake and low fruit and vegetable intake on the long-term bone health of Hong Kong Chinese adolescents warrants attention.

Effectiveness of a lifestyle modification programme in weight maintenance in obese subjects after cessation of treatment with Orlistat

OBJECTIVE

To examine the efficacy of a lifestyle modification programme in weight maintenance for obese subjects after cessation of treatment with Orlistat.

METHODS

Fifty-five subjects with and without diabetes mellitus were randomized to a lifestyle modification programme or to usual care at the end of 6 months' treatment with Orlistat. The intervention programme was nutritionist led, consisting of components of dietary management, physical activity, peer group support and discussion using techniques of self-monitoring, stimulus control and cognitive restructuring. Anthropometric indices, body composition, basal metabolic rate, blood pressure, fasting glucose, glycosylated haemoglobin, lipid profile, 24-hour urinary albumin excretion, dietary intake, physical activity level, and quality of life were assessed before and after the intervention period. Results Subjects in the intervention group maintained their weight loss and favourable anthropometric, metabolic, dietary intake, physical activity and quality of life profiles, while most parameters deteriorated in the usual care group, being more marked in subjects with diabetes. The magnitude of weight gain was comparable to that lost during Orlistat treatment.

CONCLUSION

A specially designed nutritionist-led lifestyle modification programme for obese subjects is effective in weight maintenance after treatment with Orlistat, in the absence of which the benefits of drug treatment were lost. The magnitude of the effect of lifestyle modification is comparable to that observed with Orlistat.

Nutrient intake during peritoneal dialysis at the Prince of Wales Hospital in Hong Kong

BACKGROUND

Individuals undergoing peritoneal dialysis are at increased risk of developing cardiac disease and malnutrition.

STUDY DESIGN

A cross-sectional survey.

SETTINGS AND PARTICIPANTS

249 Chinese continuous ambulatory peritoneal dialysis (CAPD) patients were recruited from the Prince of Wales Hospital in Hong Kong. Another 249 age- and sex-matched controls were recruited from an archive of 1,010 individuals with known food frequency questionnaire (FFQ) data.

OBJECTIVE

To compare the dietary intake pattern of CAPD patients with controls and evaluate its association with background cardiac disease.

OUTCOMES AND MEASUREMENTS

Intake of different nutrients was estimated by using a 7-day FFQ.

RESULTS

Intake of all nutrients was lower in CAPD patients than controls, with resulting lower overall energy intake. Nutrient intake was decreased further in CAPD patients with background cardiac disease, which corresponded to worse nutritional status. Controlling for age, male sex, body weight, diabetes mellitus, dialysis therapy duration, residual renal function, peritoneal dialysis urea clearance, and Charlson Comorbidity Index score, background cardiac disease was associated independently with less intake of energy and most macronutrients and micronutrients. However, the association between background cardiac disease and energy and most nutrient intake was decreased or even lost when additional adjustment was made for C-reactive protein and serum albumin levels.

LIMITATIONS

An FFQ is limited in that nutrient quantitation is not exact and may be underestimated as a result of underreporting by patients. CAPD patients were compared with a control group without cardiovascular disease ascertainment that did not include subjects with diabetes.

CONCLUSIONS

Chinese CAPD patients had significantly lower nutrient intake than age- and sex-matched controls. The association between cardiac disease and lower dietary macronutrient and micronutrient intake in CAPD patients was mediated in part through systemic inflammation, which also was associated with more malnutrition. More attention should be focused on improving the intake pattern of Chinese CAPD patients.

Influence of dietary pattern on the development of overweight in a Chinese population

OBJECTIVE

To examine dietary factors predisposing to overweight and obesity, taking into account age, gender, education level and physical activity.

DESIGN

Longitudinal population study.

SETTING

Community living subjects in Hong Kong.

SUBJECTS

One thousand and ten Chinese subjects participating in a territory wide dietary and cardiovascular risk factor prevalence survey in 1995-1996 were followed up for 5-9 years.

MEASUREMENTS

Body mass index (BMI) was measured. Information was collected on factors predisposing to development of overweight and obesity (age, gender, education level, physical activity, macronutrient intake, Mediterranean diet score and food variety), and the predisposing dietary factors examined, adjusted for other confounding factors, using logistic regression.

RESULTS

The 5-9-year incidence of overweight is 22.6% (BMI > or =23 kg/m2, 95% confidence interval (CI)=15.0-30.1%) or 11.5% (BMI > or =25 kg/m2, 95% CI=7.3-15.7%), and for obesity (BMI >/=30 kg/m2) is 0.6% (95% CI=-0.2-1.4%). The corresponding figures for women were 14.1% (95% CI=8.8-19.5%), 9.7% (95% CI=6.0-13.4%) and 3% (95% CI=1.3-4.8%). After adjusting for confounding factors (age, sex, education and physical activity), increased variety of snack consumption was associated with increased risk of developing overweight (BMI > or =23 kg/m2) in the Hong Kong Chinese population over a 5-9-year period.

CONCLUSION

Increased variety of snack consumption may predispose to weight gain over a 5-9-year period.

Nutrient intake and psychological health in an elderly Chinese population

BACKGROUND

Associations between nutrition and cognitive impairment, and nutrition and depression, have been observed. Elderly people are at risk of under nutrition, and also have higher prevalence of cognitive impairment and depression.

OBJECTIVE

To examine the relationship between nutrient intake and psychological health in the elderly, adjusting for confounding factors.

SUBJECTS

Three thousand nine hundred and ninety-nine men and women aged 65 years and over living in the community, with approximately equal numbers in three age groups: 65-69, 70-74, 75+ years.

METHODS

Dietary intake was assessed using a 7-day food frequency questionnaire. Cognitive function was assessed by the cognitive part of the Community Screening Instrument for Dementia (CSID). Depression was assessed using the Geriatric Depression Scale (GDS). Information was also collected for confounding factors: demographics, educational level, socioeconomic status, medical history, smoking, alcohol intake, and physical activity. Logistic regression analyses were carried out to examine associations between lifestyle and dietary variables, and CSID and GDS, controlling for confounders.

RESULTS

Both CSID and GDS scores were associated with co-morbidity, demographic and socioeconomic factors. Few associations between lifestyle factors and CSID score were observed. Dietary factors inversely associated with GDS score include total fat intake, vitamins A, B2, B3, C, fibre, and vegetables. In terms of nutrient density, iron and isoflavone intake were additional factors.

CONCLUSION

Association exists between intake of various nutrients and psychological health independent of other confounding factors in the elderly population. A follow-up study of this cohort or interventional studies are needed to elucidate cause effect relationship.

Questionário de freqüência de consumo alimentar e recordatório de 24 horas: aspectos metodológicos para avaliação da ingestão de lipídeos

A adequada avaliação da ingestão lipídica, por meio de inquéritos alimentares, é de interesse em estudos populacionais, visto que os lipídeos estão envolvidos tanto no desenvolvimento quanto na prevenção de doenças arteriais coronarianas. Os inquéritos de consumo alimentar consistem em métodos indiretos de avaliação do estado nutricional, que estão sujeitos a erros inerentes ao indivíduo e à metodologia do estudo. É fundamental que tais métodos, particularmente o questionário de freqüência de consumo alimentar sejam validados para a população em estudo. Entre os principais erros que envolvem a avaliação de consumo de lipídeos, incluem-se a variabilidade intrapessoal, que pode ser minimizada com o aumento do número de recordatórios analisados e por técnicas estatísticas. O uso de biomarcadores para estimar o consumo alimentar a longo prazo é cada vez mais utilizado e apresenta um importante papel na correta avaliação do consumo real de lipídeos. Nesse contexto, pretende-se com este trabalho discutir aspectos metodológicos para estimar a ingestão de lipídeos pela população. Discutem-se aspectos relacionados aos erros de avaliação da ingestão alimentar, aspectos relacionados à utilização do questionário de freqüência de consumo alimentar e do recordatório de 24 horas, a importância de estudos utilizando biomarcadores e a utilização de inquéritos alimentares para estimar o consumo de lipídeos.

A quantitative food frequency questionnaire for women in southeast China: development and reproducibility

This study describes the development and reproducibility of a 128-item quantitative food frequency questionnaire (FFQ) to measure usual food consumption for women in southeast China. The FFQ was pre-tested using 51 Chinese women who recently migrated to Australia. Cronbach's alpha coefficient was 0.81 for internal consistency. The reliability of the FFQ was then assessed by another test-retest study. A sample of 41 women residing in southeast China was interviewed twice within 12 weeks. Intraclass correlation coefficients were moderate to high for mean food group consumption (0.43-0.96) and mean daily nutrient intakes (0.47-0.89). Kappa statistics for eating habits ranged from 0.27 to 0.89 in the test-retest. The mean ratio of energy intake to basal metabolic rate was 1.73 (S.D. 0.39) in both test and retest samples. The study confirmed that the FFQ method using standard containers is appropriate to assess dietary intake for women in southeast China.

Correlates for a low ankle-brachial index in elderly Chinese

This study examines the prevalence of atherosclerosis (using ankle-brachial index (ABI) value <0.9) and associated socioeconomic and lifestyle factors in elderly Chinese, adjusting for presence of cardiovascular diseases and body mass index, in a cross-sectional survey of 1999 men and 1999 women aged 65 years and over living in the community. A questionnaire containing information regarding socioeconomic status, medical history and lifestyle factors was administered. Measurement included height, weight, percentage body fat using dual-energy X-ray absorptiometry and ABI. The Hong Kong population (2000) age adjusted prevalence of ABI <0.9 was 5.3% for men and 11.0% for women. In multivariate analysis, old age, female gender, presence of cardiovascular diseases, cognitive impairment, prolonged 6 m walk, smoking habit and alcohol intake were positively associated with ABI <0.9, while negative associations were observed with Vitamin C intake >100 mg per day, with the lowest OR for the range 141-190 mg (OR 0.4). Physical activity level, and self rated higher social standing in the community, while significant in univariate analysis, were not included as independent significant factors in the multivariate model. Lifestyle factors and the female gender were independent risk factors for atherosclerosis in the elderly Chinese population.

Associations between Food Variety and Body Fatness in Hong Kong Chinese Adults

BACKGROUND

Food variety is reported to be closely associated with body fatness in Caucasians. The association has not been examined in a Chinese population.

OBJECTIVE

To examine the association between food variety and body fatness in Hong Kong Chinese adults.

DESIGN

One hundred and twenty Hong Kong Chinese adults (aged 18-50 y). Usual dietary intake over a one-week period of all subjects was assessed by using a food frequency questionnaire. Anthropometric parameters were measured using standardized methods.

RESULTS

Varieties of grain and meat were negatively correlated with obesity indices (grain vs. BMI/body fat/waist/hip circumferences: partial r = -47/-0.43/-0.46/-0.42, p < 0.001; meat vs. BMI/body fat/waist/hip circumferences: partial r = -0.31/-0.24/-0.25/-0.29, p < 0.01). In contrast, there was a positive relationship between variety of snack and obesity indices (snack vs. BMI/body fat/waist/hip circumferences: partial r = 0.35/0.42/0.42/0.36, p < 0.001). A food variety ratio derived from varieties of snack, grain and meat, was a stronger predictor of body fat compared with dietary fat in a regression model.

CONCLUSION

Food variety may contribute to the local escalation in the prevalence of obesity. The variety of snack is the promoting factor for obesity while the variety of grains and meats may counteract its development. The findings of this study may have implications for treatment of obesity and the prevention of further weight gain.

Reliability and validity of a food-frequency questionnaire for Chinese postmenopausal women

OBJECTIVES

(1). To determine the reliability and validity of a food-frequency questionnaire (FFQ) for use in epidemiological research in postmenopausal women; and (2). to compare the volume estimation (VE) and weight estimation (WE) method of administration of this questionnaire.

DESIGN

An initial list of foods was derived and modified after pre-testing in 22 subjects. Test-retest reliability was assessed in 21 subjects who had repeat administrations of the questionnaire 14 days apart (FFQ1, FFQ2). The validity of the FFQ was assessed by comparing nutrient intakes with those from a 4-day food record.

SETTING

Chengdu, People's Republic of China.

SUBJECTS

Twenty-two postmenopausal women (50-70 years) were recruited from The Second University Hospital, West China University of Medical Sciences, Chengdu and participated in the pre-test. Another 21 women (50-70 years) were randomly selected from the general population of all five districts of Chengdu and participated in the reliability and validity sub-studies.

RESULTS

Energy, protein, carbohydrate, magnesium and sodium intakes in this sample were less than the Recommended Dietary Allowances (RDAs) for 45-70-year-old women in China. Intake of non-cooking fat was higher than the Chinese RDA. Pearson correlation coefficients and intra-class correlation coefficients (ICCs) for reliability of the VE FFQ ranged from 0.51 to 0.85 and from 0.51 to 0.81, respectively; for the WE FFQ, they ranged from 0.22 to 0.86 and from 0.21 to 0.81. Correlation coefficients and ICCs for validity of the WE FFQ ranged from 0.36 to 0.69 and from 0.34 to 0.57, respectively; corresponding values for the VE FFQ were -0.30 to 0.65 and -0.14 to 0.65.

CONCLUSIONS

Both the VE and WE FFQs were reliable and valid except for sodium intake. The VE FFQ provided more valid estimates of nutrient intakes than did the WE FFQ.

Is a single time point C-reactive protein predictive of outcome in peritoneal dialysis patients?

C-reactive protein is the prototype marker of inflammation and has been shown to predict mortality in hemodialysis patients. However, it remains uncertain as to whether a single C-reactive protein level has similar prognostic significance in peritoneal dialysis patients. A single high-sensitivity C-reactive protein (hs-CRP) level was measured in 246 continuous ambulatory peritoneal dialysis patients without active infections at study baseline together with indices of dialysis adequacy, echocardiographic parameters (left ventricular mass index, left ventricular dimensions, and ejection fraction), nutrition markers (serum albumin, dietary intake, and subjective global assessment) and biochemical parameters (hemoglobin, lipids, calcium, and phosphate). The cohort was then followed-up prospectively for a median of 24 mo (range, 2 to 34 mo), and outcomes were studied in relation to these parameters. Fifty-nine patients died (36 from cardiovascular causes) during the follow-up period. The median hs-CRP level was 2.84 mg/L (range, 0.20 to 94.24 mg/L). Patients were stratified into tertiles according to baseline hs-CRP, namely those with hs-CRP < or = 1.26 mg/L, 1.27 to 5.54 mg/L, and > or = 5.55 mg/L. Those with higher hs-CRP were significantly older (P < 0.001), had greater body mass index (P < 0.001), higher prevalence of coronary artery disease (P = 0.003), and greater left ventricular mass index (P < 0.001). One-year overall mortality was 3.9% (lower) versus 8.8% (middle) versus 21.3% (upper tertile) (P < 0.0001). Cardiovascular death rate was 2.7% (lower) versus 5.2% (middle) versus 16.2% (upper tertile) (P < 0.0001). Multivariable Cox regression analysis showed that every 1 mg/L increase in hs-CRP was independently predictive of higher all-cause mortality (hazard ratio [HR], 1.02; 95% CI, 1.01 to 1.04; P = 0.002) and cardiovascular mortality (HR, 1.03; 95% CI, 1.01 to 1.05; P = 0.001) in peritoneal dialysis patients. Other significant predictors for all-cause mortality included age (HR, 1.07; 95% CI, 1.04 to 1.10), gender (HR, 0.49; 95% CI, 0.27 to 0.90), atherosclerotic vascular disease (HR, 2.65; 95% CI, 1.46 to 4.80), left ventricular mass index (HR, 1.01; 95% CI, 1.00 to 1.01) and residual GFR (HR, 0.53; 95% CI, 0.38 to 0.75). Age (HR, 1.06; 95% CI, 1.02 to 1.10), history of heart failure (HR, 3.31; 95% CI, 1.36 to 8.08), atherosclerotic vascular disease (HR, 3.20; 95% CI, 1.43 to 7.13), and residual GFR (HR, 0.57; 95% CI, 0.38 to 0.86) were also independently predictive of cardiovascular mortality. In conclusion, a single, random hs-CRP level has significant and independent prognostic value in PD patients.

Diet and glucose tolerance in a Chinese population

BACKGROUND

Associations between dietary factors and glucose tolerance observed in Caucasian populations may not be applicable to Chinese populations, since the traditional Chinese diet contains plentiful vegetables and is rice-based (which has a lower glycemic index than potatoes). To address this question, the dietary patterns in 988 Hong Kong Chinese subjects with normal and impaired glucose tolerance, and diabetes, were examined in a cross sectional survey to determine if there is any association between diet and glucose tolerance.

METHOD

A stratified random population sample of 988 subjects (488 male, 500 female) was recruited. A food frequency questionnaire was used to determine dietary intake, and glucose tolerance was examined using the glucose tolerance test and the WHO criteria used to classify subjects into the three glucose tolerance categories.

RESULTS

Using the standardized world population of Segi, the prevalence rate for DM was 6.6% for men and 5.7% for women; and for IGT 10.3% for men and 15.4% for women aged 30-64 y. Abnormal glucose tolerance is associated with female gender, older age, lower educational attainment and higher body mass index (BMI). No clear pattern of association with dietary factors was observed after adjusting for confounding factors. However, if subjects with BMI>or=25 kg/m(2) were excluded, an increase in mean consumption of rice/noodles/pasta per week was observed in the DM group, after adjusting for total energy intake and other confounding factors. No association between dietary variety, which has been linked with body fatness, and glucose tolerance, was observed.

CONCLUSION

Dietary habit may not be a strong risk factor for the development of glucose intolerance in Chinese populations, given the favorable features of the Chinese diet. The high consumption of rice in the DM subjects who are of normal BMI suggests that further studies examining glycemic indices of Chinese food items may be beneficial. Obesity still remains the most important predisposing factor.

Important factors other than dialysis adequacy associated with inadequate dietary protein and energy intakes in patients receiving maintenance peritoneal dialysis

BACKGROUND

Anorexia that results in inadequate nutrient intake is considered one of the most important causes of malnutrition in dialysis patients.

OBJECTIVE

The objective was to determine factors other than dialysis adequacy that are associated with inadequate protein and energy intakes in patients receiving continuous ambulatory peritoneal dialysis.

DESIGN

Dietary protein and energy intakes were assessed with a food-frequency questionnaire in 266 patients, and factors other than dialysis adequacy that are potentially associated with reductions in energy and protein intakes were examined.

RESULTS

Only 39% of the patients had protein intakes > or = 1.2 g x kg(- 1) x d(- 1), and 26% had energy intakes > or = 126 kJ x kg(- 1) x d(- 1). Other than having a greater total urea clearance and glomerular filtration rate, patients with protein intakes > or = 1.2, as opposed to < 1.2, g x kg(- 1) x d(- 1) had lower high-sensitive C-reactive protein concentrations and fewer complications with volume overload (29% compared with 46%; P = 0.006). Patients with energy intakes > or = 126, as opposed to < 126, kJ x kg(- 1) x d(- 1) were younger, had lower high-sensitive C-reactive protein concentrations, and had a lower prevalence of diabetes (P = 0.006), atherosclerotic vascular disease (P = 0.020), and history of volume overload (P = 0.013). Multiple regression analysis showed that other than increasing age, diabetes, and total urea clearance, having a history of volume overload was independently associated with a 0.22-g x kg(- 1) x d(- 1)decrease in protein (P = 0.001) and a 13.07-kJ x kg(- 1) x d(- 1) decrease in energy intake (P = 0.006).

CONCLUSION

An important yet unrecognized association was observed between a history of volume overload and dietary intake in peritoneal dialysis patients.

Independent effects of residual renal function and dialysis adequacy on dietary micronutrient intakes in patients receiving continuous ambulatory peritoneal dialysis

BACKGROUND

Dialysis patients are at risk of vitamin and mineral deficiencies, not only because of losses during chronic hemodialysis or peritoneal dialysis but also because of low intakes.

OBJECTIVE

The objective was to determine the importance of urea clearance (calculated as K(t)/V) and residual renal function (RRF) in predicting micronutrient intakes in a large cohort of patients receiving continuous ambulatory peritoneal dialysis (CAPD).

DESIGN

We conducted a survey of dietary intakes in 242 CAPD patients and divided them into 3 groups according to their weekly urea clearance and RRF: WD group (n = 84), a urea clearance >/= 1.7 and a glomerular filtration rate (GFR) >/= 1 mL x min(-1) x 1.73 m(-2); DD group (n = 71), a urea clearance >/= 1.7 and a GFR < 1 mL x min(-1) x 1.73 m(-2); and ID group (n = 87), a urea clearance < 1.7.

RESULTS

Most of the patients had intakes of water-soluble vitamins and minerals that were lower than the recommended dietary allowance; most intakes were significantly higher in the WD group than in the DD and ID groups, except those of niacin and calcium. After age, sex, body weight, and the presence of diabetes were controlled for, total weekly urea clearance and the GFR (but not peritoneal dialysis urea clearance) were significantly associated with intakes of vitamins A and C, the B vitamins, and minerals (calcium, phosphate, iron, and zinc). Low intakes of vitamins and minerals with low RRF and urea clearance were the result of reduced overall food intakes, except for thiamine, vitamin B-6, and folic acid, which were deficient in the diet.

CONCLUSIONS

Supplementation with most water-soluble vitamins and minerals, including iron and zinc, should be considered in CAPD patients, especially those with low RRF and low urea clearance. The optimal dose needs to be determined.

Independent effects of residual renal function and dialysis adequacy on actual dietary protein, calorie, and other nutrient intake in patients on continuous ambulatory peritoneal dialysis

Previous studies have suggested that the cross-sectional relationship observed between total solute clearance (Kt/V) and dietary protein intake (DPI) in patients undergoing dialysis is possibly mathematical in origin. A cross-sectional study on 242 patients undergoing continuous ambulatory peritoneal dialysis (CAPD) was performed to determine the differential effects of dialysis adequacy and residual renal function (RRF) on actual dietary intake. All patients underwent a 7-d food frequency questionnaire to quantify daily dietary protein, calorie (DCI), and other nutrient intake, subjective global assessment (SGA), and collection of 24-h dialysate and urine for total (PD and renal) Kt/V and RRF. Patients were categorized into three groups: I (n = 94), total Kt/V >/=1.7 and GFR >0.5 ml/min per 1.73 m(2); II (n = 58), total Kt/V >/=1.7 but GFR <0.5 ml/min per 1.73 m(2); and III (n = 90), total Kt/V <1.7. Sixty-nine percent versus 62% versus 42% of group I versus II versus III patients were well nourished according to SGA (P = 0.004). DPI (1.23 [0.47] versus 1.12 [0.49] versus 0.99 [0.40] g/kg per d; P = 0.002) and DCI (27.3 [8.9] versus 23.8 [8.6] versus 23.0 [8.2] kcal/kg per d; P = 0.002) showed significant decline across the three groups. Intake of other nutrients, including carbohydrate, fat, fatty acids, and cholesterol was higher for group I compared with groups II and III. Adjusting for age, gender, weight, and diabetes, every 1 ml/min per 1.73 m(2) increase in GFR was associated with a 0.838-fold increase in DCI (95% confidence interval to interval, 0.279 to 1.397; P = 0.003) and a 0.041-fold increase in DPI (95% confidence interval, 0.009 to 0.072; P = 0.012), whereas every 0.25-unit increase in total (PD and renal) Kt/V was associated with a 0.570-fold increase in DCI (95% confidence interval, 0.049 to 1.092; P = 0.032) and a 0.052-fold increase in DPI (95% confidence interval, 0.023 to 0.081; P = 0.001). Greater small-solute clearances are associated with better dietary intake and better nutrition. The study confirmed significant and independent effect of RRF, but not PD solute clearance, on actual DPI, DCI, and other nutrient intake in patients on CAPD.

Dietary intake and practices in the Hong Kong Chinese population

OBJECTIVES

To examine dietary intake and practices of the adult Hong Kong Chinese population to provide a basis for future public health recommendations with regard to prevention of certain chronic diseases such as cardiovascular disease, hypertension, and osteoporosis.

PARTICIPANTS

Age and sex stratified random sample of the Hong Kong Chinese population aged 25 to 74 years (500 men, 510 women).

METHOD

A food frequency method over a one week period was used for nutrient quantification, and a separate questionnaire was used for assessment of dietary habits. Information was obtained by interview.

RESULTS

Men had higher intakes of energy and higher nutrient density of vitamin D, monounsaturated fatty acids and cholesterol, but lower nutrient density of protein, many vitamins, calcium, iron, copper, and polyunsaturated fatty acids. There was an age related decrease in energy intake and other nutrients except for vitamin C, sodium, potassium, and percentage of total calorie from carbohydrate, which all increased with age. Approximately 50% of the population had a cholesterol intake of < or = 300 mg; 60% had a fat intake < or = 30% of total energy; and 85% had a percentage of energy from saturated fats < or = 10%; criteria considered desirable for cardiovascular health. Seventy eight per cent of the population had sodium intake values in the range shown to be associated with the age related rise in blood pressure with age. Mean calcium intake was lower than the FAO/WHO recommendations. The awareness of the value of wholemeal bread and polyunsaturated fat spreads was lower in this population compared with that in Australia. There was a marked difference in types of cooking oil compared with Singaporeans, the latter using more coconut/palm/mixed vegetable oils.

CONCLUSION

Although the current intake pattern for cardiovascular health for fat, saturated fatty acid, and cholesterol fall within the recommended range for over 50% of the population, follow up surveys to monitor the pattern would be needed. Decreasing salt consumption, increasing calcium intake, and increasing the awareness of the health value of fibre may all be beneficial in the context of chronic disease prevention.