Noncitrus fruits as novel dietary environmental modifiers of iron stores in people with or without HFE gene mutations

OBJECTIVE

To investigate whether citrus fruit, noncitrus fruit, and other dietary factors act as environmental modifiers of iron status in the absence or presence of hemochromatotic HFE gene mutations.

PARTICIPANTS AND METHODS

Iron studies, HFE genotypic analyses, and dietary data from a survey conducted from March 21, 1994, through December 15, 1995, were analyzed for a group of 2232 residents (1105 men, 1127 women) aged 20 to 79 years recruited from the community electoral roll of Busselton in Western Australia. Data were analyzed by linear regression analysis and analysis of covariance.

RESULTS

Higher levels of fresh fruit intake (excluding citrus fruits and citrus juices) had a significant protective effect (P=.002) against high body iron status as gauged by ferritin levels in men, irrespective of HFE genotype. Consumption of 2 or more pieces of fruit per day on average reduced mean serum ferritin levels by 20% compared with average consumption of less than 1 piece of fruit per day. This effect was not observed in women. Consumption of citrus fruits and citrus juices had no significant effects in either sex. No protective effects were observed for tea consumption or any other dietary factors studied. Red meat and alcohol consumption correlated with high body iron stores (P<.05), consistent with previous studies, but did not interact with fruit with regard to effects on serum ferritin (P>.05).

CONCLUSION

Noncitrus fruits are environmental modifiers of iron status independent of HFE genotype. This could have important implications for the provision of evidence-based dietary advice to patients with other iron-storage disorders.

Evaluating the impact of repeated community-wide health surveys on cardiovascular morbidity and mortality in the Busselton population

OBJECTIVE

To evaluate the impact of repeated community-wide mass health examinations on cardiovascular mortality and hospital morbidity trends in Busselton.

METHOD

Population census, hospital admission and death data were used to calculate and compare cardiovascular mortality rates from 1965 to 1998 and hospital morbidity rates from 1971 to 1998 in Busselton residents aged 40 to 84 years with the remainder of the south-west region of Western Australia.

RESULTS

Among men aged 40-69 years, the calendar year trends in standardised cardiovascular mortality and morbidity ratios were relatively flat and non-significant. Among women aged 40-69 years, the mortality ratio declined significantly up to 1989 (p = 0.03) but not over the whole period (p = 0.12), and the downward trend in the morbidity ratio did not reach statistical significance (p = 0.21). Among men aged 70-84 years, both the mortality and morbidity ratios rose significantly over time, whereas among women aged 70-84 years the mortality ratios showed a flat trend and the morbidity ratios a rising trend. These increasing trends were opposite to what was expected if the surveys had a beneficial impact.

CONCLUSION

This analysis of trends, while failing to demonstrate a clear benefit of repeated mass health screenings on cardiovascular event rates, also highlights the difficulties in evaluating the longer-term impact on event rates of such programs and suggests that negative conclusions should be made with caution.

What can Busselton population health surveys tell us about asthma in older people?

WHAT WE NEED TO KNOW: Do the characteristics of asthma differ in people older than 55 years compared with younger people with respect to risk factors (atopy, airway hyper-responsiveness and genetic variation), smoking, lung function and other illness? How do inflammation and remodelling of airways vary with age and with duration and severity of asthma? WHAT WE NEED TO DO: Continue collecting prevalence data for asthma and its risk factors. Assess (i) period and cohort effects on asthma and its risk factors and (ii) interactions between age, smoking, severity and duration of asthma, lung function and airway responsiveness, and other concurrent disease. Measure airway responsiveness and exhaled nitric oxide to detect airway abnormalities in older people and relate this to the diagnoses of asthma and other diseases.

Population-based study of the relationship between mutations in the hemochromatosis (HFE) gene and arthritis

BACKGROUND AND AIM

Mutations in the hemochromatosis (HFE) gene are carried by one in three individuals of British Isles descent and may result in increased iron stores. These increased iron stores could potentially induce or exacerbate diseases, such as arthritis, in which iron has a role in pathogenesis. Although arthritis is a well-known association of clinically overt hereditary hemochromatosis, controversy surrounds the role of mutations in the HFE gene as risk factors for arthritis. The aim of the present study was to determine whether mutations in the HFE gene are associated with an increased prevalence of arthritis.

METHODS

A population-based study was conducted in Busselton, Western Australia, of the prevalence of arthritis in 1372 individuals of British Isles descent. Participants completed a questionnaire and general physical examination. Analysis for C282Y and H63D HFE mutations was undertaken. Unadjusted and adjusted odds ratios (OR) were calculated for the relationship between HFE mutations and the prevalence of self-reported, doctor-diagnosed arthritis.

RESULTS

There was no association between the presence of HFE mutations and the prevalence of self-reported, doctor-diagnosed arthritis (C282Y/wild type (WT) adjusted OR = 1.041 (95% confidence interval (CI) 0.68-1.61), H63D/WT OR = 0.76 (95% CI 0.53-1.08), C282Y/C282Y OR = 0.39 (95% CI 0.04-3.63), C282Y/H 63D OR = 0.808 (95% CI 0.27-2.42), H63D/H63D OR = 0.419 (95% CI 0.13-1.36)). Overall adjusted OR for arthritis in participants with one or more HFE mutations was 0.81 (95% CI 0.61-1.09).

CONCLUSIONS

Mutations of the HFE gene are not risk factors for arthritis in populations of British Isles descent.

Correlates of habitual snoring and witnessed apnoeas in Busselton, Western Australia

OBJECTIVE

The aim of this study was to identify potential body size, behavioural and respiratory risk factors for habitual snoring and witnessed apnoeas in a general population.

METHODS

Correlates of these conditions were studied in a sample of 3,577 adults aged 25-74 years who participated in a comprehensive health survey in Busselton, Western Australia, during 1994/95. Logistic regression was used to assess associations after age and gender adjustment and also in multivariate models.

RESULTS

The prevalence of both conditions was higher in men and rose with age. After controlling for age, gender and body mass index no additional body size variable remained significantly associated with witnessed apnoeas, whereas both waist-hip ratio and neck-height ratio remained significantly associated with habitual snoring. Among behavioural variables, smoking showed the strongest association, and among respiratory symptoms, asthma for habitual snoring and bronchitis for witnessed apnoeas had significant independent associations.

CONCLUSIONS AND IMPLICATIONS

This study has confirmed obesity and smoking as key determinants of habitual snoring and witnessed apnoeas. It has also shown that a number of measures of obesity are independently related to habitual snoring and that asthma and bronchitis may also play a role, independently of obesity.

Effects of HFE gene mutations and alcohol on iron status, liver biochemistry and morbidity

BACKGROUND AND AIMS

The aims of the present study were to determine: (i) whether alcohol consumption is greater in individuals with HFE mutations; and (ii) whether common HFE mutations modify the effects of alcohol on serum iron and liver biochemistry or morbidity.

METHODS

The residents of the town of Busselton in Western Australia were subject to cross-sectional health surveys between 1966 and 1983. In 1994/1995 all surviving participants of the earlier surveys were invited to take part in a follow-up survey. Logistic, linear and Poisson log-linear regression analyses were performed in 1490 men and 1452 women from the 1994/1995 survey to assess the relationships between HFE mutations, alcohol, iron levels, liver biochemistry and morbidity.

RESULTS

Heavy or moderate alcohol consumption was present in 7% or 36% of men and 0.5% or 12% of women, respectively. Alcohol consumption strongly influenced levels of serum ferritin and gamma glutamyl transpeptidase (GGT) and mean cell volume (MCV) in men and women but only alanine aminotransferase (ALT) levels in women. These effects were independent of HFE gene mutations. Hospital admission rates for respiratory disorders were higher in men with the C282Y mutation.

CONCLUSIONS

Alcohol consumption strongly influences serum ferritin and GGT levels and MCV in men and women but only ALT levels in women, and these effects are independent of HFE mutations. HFE gene mutations do not predispose to moderate or heavy alcohol consumption. The C282Y mutation is associated with increased respiratory admission rates in men.

Spouse selection and environmental effects on spouse correlation in lung function measures

PURPOSE

Concordance between spouses may be due to partner selection factors and/or the effects of marriage/environment. The extent to which partner selection factors contribute to spouse concordance has important implications for heritability studies. The aim of this study was to examine the magnitude of spouse correlation in lung function measures and its relationship to duration of marriage.

METHODS

Cross-sectional and longitudinal data collected over the period 1969 to 1995 for 2615 couples from the Busselton Health Study have been analyzed using the program FISHER.

RESULTS

Unadjusted correlations were around 0.45 for forced expiratory volume in 1 second (FEV1) and 0.25 for FEV1/FVC (forced vital capacity) and were reduced to 0.05 and 0.10, respectively, after adjustment for age, height, and smoking. No trend with marriage duration was apparent in both cross-sectional and longitudinal analyses but there was a significant downward trend in the correlations with age at marriage.

CONCLUSIONS

The findings indicate that observed correlations in lung function measures are mostly due to partner selection factors and that partner selection factors have greater influence for couples that marry at younger ages. Family studies that aim to identify and separate genetic from other influences on lung function measures should not regard the mother-father correlation as due to common environment effects.

Serum ferritin and cardiovascular disease: a 17-year follow-up study in Busselton, Western Australia

The association between serum ferritin level and coronary heart disease (CHD) and stroke events was evaluated in a long-term Western Australia prospective study in 1981-1998. The cohort consisted of the 1612 men and women aged 40-89 years who participated in the 1981 Busselton Health Survey and who were free of cardiovascular disease at that time. Serum ferritin levels were obtained from serum samples stored frozen since 1981. The outcomes of interest were time to first CHD event (hospital admission or death) and time to first stroke event. Case-cohort sampling was used to reduce costs and preserve serum but still allow efficient analysis. Ferritin assays were performed for 217 CHD cases, 118 stroke cases, and a random sample of 450 of the total cohort. Proportional hazards regression models were used to obtain age-adjusted and multivariate-adjusted hazard ratios for ferritin level in relation to CHD and stroke. The hazard ratio for the highest tertile group compared with the lowest group was 0.96 (95% confidence interval: 0.60, 1.53) for CHD and 1.43 (95% confidence interval: 0.78, 2.64) for stroke. Little or no evidence was found that ferritin level was a risk factor for cardiovascular disease.

Health status of users of hormone replacement therapy by hysterectomy status in Western Australia

STUDY OBJECTIVES

To compare the demographic, behavioural, and biological correlates of use of hormone replacement therapy (HRT) in women with an intact uterus and women who have undergone hysterectomy.

DESIGN

Cross sectional analysis of data from the Busselton Health Study and the 1994 Healthway-National Heart Foundation Risk Factor Survey.

SETTING

Busselton and Perth, Western Australia, 1994.

PARTICIPANTS

2540 women aged 35-79 years.

MAIN OUTCOME MEASURES

Demographic, behavioural, and biological correlates of use of HRT by hysterectomy status.

RESULTS

In women with an intact uterus, after adjustment for age and place of residence, current use of HRT was significantly associated with having a professional level of occupation, ever use of alcohol, having a history of smoking, and a lower body mass index. Current users of HRT had significantly lower levels of total cholesterol and higher levels of triglycerides than non-users. In women who had undergone hysterectomy, the only non-biological characteristic associated with use of HRT was having a history of smoking. Current users of HRT had lower levels of systolic blood pressure, lower levels of LDL cholesterol, higher levels of HDL cholesterol, and higher levels of triglycerides. The association between use of HRT and participation in exercise, level of systolic blood pressure, level of HDL cholesterol, and total/HDL cholesterol ratio varied significantly by hysterectomy status. After adjustment for age and place of residence, the mean levels of systolic and diastolic blood pressure, body mass index, waist/hip ratio, LDL cholesterol, and total/HDL cholesterol ratio were highest in women who had undergone hysterectomy and were not using HRT.

CONCLUSIONS

Demographic/behavioural and biological correlates of use of HRT varied depending on hysterectomy status. Demographic and behavioural characteristics were more important as selection factors for use of HRT in women with an intact uterus than in women who had undergone hysterectomy. Women who had undergone hysterectomy and were not using HRT had a significantly worse profile for CHD than did women with an intact uterus. These results indicate that any bias in estimates of the protective effect of HRT on risk of CHD in observational studies is likely to depend on the prevalence of hysterectomy within the study population. Hysterectomy status needs to be taken into account in any studies that investigate the effect of HRT on risk of CHD.

Familial aggregation and heritability of adult lung function: results from the Busselton Health Study

Decreased spirometric indices are characteristic of asthma and other respiratory diseases. The aim of this study was to investigate the genetic and environmental components of variance of forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) measured in adulthood in an Australian population-based sample of 468 Caucasian nuclear families. The inter-relationships of the genetic determinants of these traits with asthma and atopic rhinitis were also investigated. Serial cross-sectional studies were conducted in the town of Busselton in Western Australia between 1966 and 1981 and follow-up of previous attendees was undertaken in 1995. Data from each subject included in this study were from a single survey in adulthood (25-60 yrs of age) when the subject was as close to age 45 yrs as possible. Multivariate analysis suggested that FEV1 and FVC levels were associated with age, sex, height, tobacco smoke exposure, asthma and atopic rhinitis. After adjustment for relevant covariates, FEV1 levels had a narrow-sense heritability (h2N) of 38.9% (SE 9.1%). FVC levels had an h2N of 40.6% (SE 8.9%). Extended modelling demonstrated little overlap in the genetic determinants of asthma or atopic rhinitis and either FEV1 or FVC levels. The results of this study were consistent with the existence of important genetic determinants of adult lung function that are independent of asthma or other atopic disease, cigarette smoking, height, age or sex.

Effect of dichotomising a continuous variable on the assessment of familial aggregation: an empirical study using body mass index data from the Busselton Health Study

BACKGROUND

Continuous measures are often dichotomised according to some meaningful threshold. When measures of association are the study focus, such as in familial aggregation studies, we may use an odds-ratio (OR), instead of a Pearson correlation coefficient, to measure correlation between outcomes. In this paper, we examine the effect of using different threshold values on the resulting OR estimates and their statistical efficiency.

METHODS

We use an example based on obesity data, in the form of BMI measurements on family members, to guide a study of the OR based on four-fold probabilities which result when a pair of normally distributed outcomes is dichotomised at a certain value. This leads to a study of outcomes from simulated nuclear family data. As a possible alternative, we also assess the performance use of a simple tetrachoric correlation coefficient, the dichotomous analogue of Pearson's correlation coefficient.

RESULTS

The studies indicate that dichotomisation at values close to the mean leads to results more comparable to the continuous equivalent. The results show that, in our setting, there is a positive relationship between threshold value and resulting OR, and between threshold value and resulting standard errors. The value of the tetrachoric correlation coefficient decreases, relative to Pearson's correlation coefficient, as threshold values deviate from the mean.

DISCUSSION

Familial OR that result from dichotomisation are influenced by the choice of threshold value. We discuss implications of this and related issues on the interpretation of results.

Lung function, respiratory symptoms, and mortality: results from the Busselton Health Study

PURPOSE

This study examines the association between lung function [percentage predicted FEV, (forced expiratory volume in 1 s)] and respiratory symptoms (asthma, bronchitis, wheeze, dyspnea) and mortality from all causes; coronary heart disease, stroke, cancer, and respiratory disease in a cohort of 2,100 men and 2,177 women in the Busselton Health Study followed for 20-26 years for mortality.

METHODS

A total of 840 men and 637 women died during the follow-up period, and Cox proportional hazards regression was used to assess the relationships between risk factors and mortality.

RESULTS

Lung function was significantly and independently predictive of mortality from all causes, coronary heart disease, cancer, and respiratory disease in both men and women, and of mortality from stroke in women. There was evidence that, among men, the association was stronger in current and former smokers as compared to those who never smoked. After adjustment for age, smoking, lung function, coronary heart disease, blood pressure, treatment for hypertension, total cholesterol, body mass index, and alcohol consumption, dyspnea was significantly related to total mortality in men and women and to respiratory disease mortality in men, and asthma was significantly related to respiratory disease mortality in women.

CONCLUSIONS

Lung function is associated with mortality from many diseases independent of smoking and respiratory symptoms. Although most respiratory symptoms are associated with smoking and lung function, after controlling for smoking and lung function, only dyspnea is associated with mortality from nonrespiratory causes.

Associations between white blood cell count, lung function, respiratory illness and mortality: the Busselton Health Study

An independent association between reduced levels of lung function and increased mortality from nonrespiratory causes has been observed in a number of studies. Since the total white blood cell count (WBC) has been related to both death from coronary heart disease and to levels of lung function, the relationship between these parameters was examined in subjects from the Busselton Health Surveys. Questionnaires regarding respiratory and cardiac illness and smoking habits were administered and total WBC, forced expiratory volume in one second (FEV1) and forced vital capacity measured in 2,105 males and 2,186 females at their initial attendance at a Busselton Health Survey in 1969, 1972 or 1975. Mortality follow-up to 1995 was completed. Multiple linear regression showed that smoking, increasing age, reduced FEV1 (% predicted) and a history of bronchitis were associated with increased WBC. Reduction of FEV1 (% pred) by 20%, a history of dyspnoea and an increase in WBC of 1,300 cells x mL(-1) were predictive of increased mortality from all causes or coronary heart disease by approximately 20, 100 and 10% respectively, independent of smoking. Removing WBC from the regression model did not significantly change the relationship between FEV1 and mortality. The study shows that the white blood cell count, forced expiratory volume in one second and dyspnoea are independently related to mortality in both males and females and that the effect of forced expiratory volume in one second on mortality is not explained by the white blood cell count.

Decline in lung function and mortality: the Busselton Health Study

BACKGROUND

There is a direct association between level of lung function, measured by forced expiratory volume in 1 second (FEV1) and mortality rates. A low FEV may result from an increased decline in FEV1 with age, which may be an independent predictor of mortality.

OBJECTIVE

To examine the association between decline in FEV1 and mortality in a cohort from a community health study.

SETTING AND METHODS

From five cross sectional studies in Busselton between 1969 and 1981 a cohort of 751 men and 940 women was identified who had three assessments of lung function over a six year period and had other health related data collected. Each subject's average FEV1 and decline in FEV1 (litre/year) were calculated from these three measurements. Mortality follow up to December 1995 was obtained. Cause of death was taken as the certified cause of death from the death certificate using ICD9 categories.

RESULTS

The average decline in FEV1 was 0.04 litre per year (SD = 0.07) for men and 0.03 litre per year (SD = 0.06) for women. Average FEV1 was significantly associated with all cause and cardiovascular disease mortality in both sexes. In women there was a significant association between decline in FEV1 and death from all causes, after adjusting for average FEV1, age, smoking, coronary heart disease, and cardiovascular disease risk factors; a 0.05 litre per year increase in the rate of decline of FEV1 increased the risk of death for all causes by 1.23 (95% confidence interval 1.06, 1.44). In men the effect of decline in FEV1 on death rate was less; for all men the hazard ratio for a 0.05 litre/year greater decline in FEV1 was 1.19 (0.99, 1.21).

CONCLUSION

Decline in lung function, measured by FEV1 is a predictor of death, independent of average FEV1 and risk factors for cardiovascular disease.

Multivariate risk estimation for coronary heart disease: the Busselton Health Study

Coronary heart disease (CHD) is a multifactorial disease and CHD risk should be estimated by assessing all cardiovascular risk factors simultaneously. Simply adding up the number of factors with 'at risk' values fails to identify high-risk subjects with multiple risk factors at moderately elevated values. A more efficient approach is to use a quantitative multivariate risk score. A number of overseas studies have produced CHD risk scoring systems for men. There are few risk scores developed for women and no CHD risk scores have been developed from Australian data. This study used data on CHD risk factors and morbidity/mortality follow-up for the 1978 Busselton Health Survey participants to provide age-specific estimates of absolute risk of CHD hospitalisation or death, and to develop multivariate CHD risk scoring systems for men and women. The scores are based on age, blood pressure, anti-hypertensive medication, total and HDL cholesterol, smoking, diabetes, left ventricular hypertrophy and previous history of CHD. The generalisability and applicability of these risk estimation systems to Australian populations in the late 1990s is discussed.

Longitudinal analysis of the effect of smoking cessation on cardiovascular risk factors in a community sample: the Busselton Study

BACKGROUND

Cessation of smoking is known to have health benefits, but individuals who give up smoking can also suffer adverse effects. This study investigated the effects of smoking cessation on cardiovascular risk factors in a community-based sample.

METHODS

Longitudinal risk factor data were analysed in 1372 women and 888 men who took part in population-based mass health screenings in the rural town of Busselton, Western Australia. Age-adjusted changes in body weight, forced expiratory volume in 1 s (FEV1), forced vital capacity, blood pressure and total cholesterol over 3-year and 6-year follow-up periods were compared for 235 ex-smokers ('quitters'), 1499 never-smokers and 526 continuing smokers.

RESULTS

In women, weight gain was larger in 'quitters' than in continuing smokers after 3 years (1.74 versus 0.32 kg, P = 0.015) and after 6 years (2.39 versus 1.24 kg, P = 0.085). Male 'quitters' had gained significantly more weight after both 3 years (2.84 versus 0.93 kg, P < 0.001) and 6 years (4.46 versus 2.40 kg, P < 0.001). Although FEV1 declined less in 'quitters' than in continuing smokers, this was statistically significant only for men and women aged less than 45 years. Smoking cessation was associated with smaller increases in cholesterol level in women, but not in men. Smoking cessation had no significant effect on changes in forced vital capacity or blood pressure.

CONCLUSIONS

Smoking cessation has different consequences for cardiovascular risk factors in men and women. Although giving up smoking is associated with weight gain in both men and women, the magnitude of the gain is larger in men. Smoking cessation has beneficial effects on lung function, especially in younger people, and on lipid levels in women, but this requires further study. Smoking cessation does not appear to influence blood pressure.

Self-reported health and use of health services: a comparison of diabetic and nondiabetic persons from a national sample

Population-based epidemiological and health service utilisation information on diabetes and other noncommunicable diseases is still scarce in Australia. Such information is needed by health economists, policy makers and service providers. Data from the 1989-90 National Health Survey conducted by the Australian Bureau of Statistics have been used to obtain estimates of the prevalence of cardiovascular morbidity, life-style factors, use of hospital and medical services, and self-assessed health and happiness for Australian persons with diabetes. Prevalences are compared with those for persons without diabetes. Those with diabetes had two to three times the prevalence of most cardiovascular conditions, similar levels of exercise (except for diabetic women over 40 years of age who exercised less than their nondiabetic counterparts), lower levels of alcohol consumption (except for younger men, who had a similar frequency of heavy drinking as their nondiabetic peers), similar levels of smoking, a higher prevalence of overweight, and significantly greater frequency of hospital admissions, use of outpatient services and general practitioner consultations. About half of the people with diabetes assessed their health as good or excellent but 90 per cent stated that they were happy or very happy. No differences between diabetic people living in capital cities and other areas were found. These results have implications for education and life-style behaviour modification programs for people with diabetes. Research into the prevention and more effective management of diabetes and its complications is required in order to contain the escalating health care burden associated with diabetes in Australia.

Familial correlations, cohabitation effects, and heritability for cardiovascular risk factors

Familial correlations in cardiovascular risk factors were investigated with use of data from a community-based sample of 1319 nuclear families involving 4178 adult persons collected in the Busselton Population Health Surveys over the period 1966 to 1981. The risk factors considered were systolic blood pressure, diastolic blood pressure, body mass index, triceps fatfold, and cholesterol. All risk factors showed positive familial correlations, with correlations generally being lower for spouses than for parent-offspring pairs or for siblings. Spouse correlations showed little variation with age, suggesting that observed correlations are primarily due to assortative mating and not to cohabitation. The parent-offspring correlations tended to decline with age of (adult) offspring; this observation suggests that the effect of a shared household environment during childhood and adolescence diminishes over time when living apart during adulthood. The sibling correlations decreased with age for blood pressure and serum cholesterol and increased with age for body mass index and triceps fatfold. The estimated heritabilities were 27% for systolic and diastolic blood pressure, 37% for serum cholesterol, 52% for body mass index, and 23% for triceps fatfold. These results confirm that substantial familial aggregation of cardiovascular risk factors occurs and that much of this aggregation has a genetic basis, although assortative mating (in spouses) and environmental influences (in offspring and siblings) are also present. The nuclear family should be considered as a point of intervention in cardiovascular disease prevention programs.

Spouse correlations in cardiovascular risk factors and the effect of marriage duration

Spouse correlations in cardiovascular risk factors were investigated using data on 2,836 spouse pairs collected in the Busselton Population Health Surveys over the period 1966-1981. The risk factors considered were systolic blood pressure, diastolic blood pressure, body mass index, triceps fatfold, cholesterol, and forced expiratory volume (1 second). Statistically significant positive correlations (p < 0.01) were found for all (age-adjusted) variables. There was a statistically significant decreasing trend in the correlations for systolic blood pressure with marriage duration (trend p < 0.01). Although no other variables showed statistically significant trends, the correlations for diastolic blood pressure (p = 0.29), body mass index (p = 0.14), and forced expiratory volume (p = 0.16) also decreased with marriage duration, and correlations for cholesterol (p = 0.61) and triceps fatfold (p = 0.99) increased with marriage duration. These results suggest that there is spousal concordance in cardiovascular risk factors. The lack of consistent increasing trends in the correlations with marriage duration suggests that assortative mating may be a more likely explanation than the sharing of a common environment.

1989-90 National Health Survey: prevalence of self-reported diabetes in Australia

OBJECTIVE

To estimate the prevalence of self-reported diabetes in a representative population sample in Australia; to identify major differences in prevalence by State and Territory and by geographic origin; and to compare trends in prevalence over time.

DESIGN

and setting: Analysis of data collected by the Australian Bureau of Statistics in the 1989-90 National Health Survey. The sampling frame (22,202 households and 54,241 people) ensured adequate representation from each State and Territory in Australia.

RESULTS

Prevalences of self-reported diabetes/high blood sugar levels were 1.9% for males and 2.0% for females over all ages; 3.1% for men and 2.9% for women aged over 25 years; and 8.1% for men and 6.9% for women aged over 65 years. Interstate differences of borderline significance were found and will require validation in larger samples. Age-standardised prevalences were higher in subjects born in Southern Europe and lower in those born in Western Europe compared with Australian-born subjects. Prevalences were high in households where the language spoken was other than English. The frequency of self-reported diabetes appears to be rising.

CONCLUSIONS

Australia has comparatively low total prevalences of self-reported diabetes/high blood sugar levels. High prevalences subsections exist, including the elderly and certain migrant groups