Determinants of general practitioner use among women in Australia

This study investigates the use of general practitioner services by women in Australia. Although there is a universal health insurance system (Medicare) in Australia, there are variations in access to services and out of pocket costs for services. Survey data from 2350 mid-age (45-50 years) and 2102 older (70-75 years) women participating in the Australian Longitudinal Study on Women's Health were linked with Medicare data to provide a range of individual and contextual variables hypothesised to explain general practitioner use. Structural equation modelling showed that physical health was the most powerful explanatory factor of general practitioner use. However, after adjusting for self-reported health, out of pocket cost per consultation was inversely associated with use of services. The out of pocket cost was generally lower for women with low socioeconomic status but cost was also directly related to geographical remoteness. Women living in more remote areas had higher out of pocket costs and poorer access to services. Women who reported better access to care were more likely to be satisfied with their most recent general practice consultation and less likely to be sceptical of the value of medical care. These results show the need for health policies that improve the equitable use of general practitioner services in Australia. (C) 2001 Elsevier Science Ltd. All rights reserved.

Dietary treatment of iron deficiency in women of childbearing age

Background: The Australian Iron Status Advisory Panel advocates dietary intervention as the first treatment option for mild iron deficiency [serum ferritin (SF) = 10-15 mug/L]. However, there appear to be no studies on the efficacy of dietary treatment for iron deficiency. Objective: We compared the effects of iron supplementation and of a high-iron diet on serum ferritin (SF) and hemoglobin in iron-deficient women of childbearing age. Design: Forty-four iron-deficient women (SF < 15 mug/L or SF = 15-20 mug/L plus serum iron < 10 mu mol/L and total-iron-binding capacity > 68 mu mol/L) and 22 iron-replete women (hemoglobin greater than or equal to 120 g/L and SF > 20 mug/L) matched for age and parity categories were enrolled and completed 7-d weighed food records at baseline. The iron-deficient women were randomly allocated to receive iron supplementation (105 mg/d; supplement group) or a high-iron diet (recommended intake of absorbable iron: 2.25 mg/d; diet group) for 12 wk. Hematologic and dietary assessments were repeated at the end of the intervention and again after a 6-mo follow-up. Results: Mean SF in the supplement group increased from 9.0 +/- 3.9 mug/L at baseline to 24.8 +/- 10.0 mug/L after the intervention and remained stable during follow-up (24.2 +/- 9.8 mug/L whereas the diet group had smaller increases during the intervention (8.9 +/- 3.1 to 11.0 +/- 5.9 mug/L) but continued to improve during follow-up (to 15.2 +/- 9.5 mug/L). Mean hemoglobin tended to improve in both intervention groups, but the change was only significant in the supplement group. Conclusions: In iron-deficient women of childbearing age, a high-iron diet produced smaller increases in SF than did iron supplementation but resulted in continued improvements in iron status during a 6-mo follow-up.

The validity of an Australian modification of the AUDIT questionnaire

The Alcohol Use Disorders Identification Test (AUDIT) has been used widely and is reported to be superior to conventional questionnaires in detection of current hazardous and harmful alcohol use. We assessed the validity of an Australian modification of the AUDIT (the AusAUDIT), which has been employed widely in Australian and New Zealand early intervention programmes. We used a cross-sectional study of 370 subjects from the follow-up phase of a randomized controlled trial of early intervention to reduce hazardous alcohol consumption. Scores on the AusAUDIT were compared against 12-month ICD-10 diagnoses of harmful alcohol use and dependence, as determined by the Composite International Diagnostic Interview, and against self-report of alcohol consumption exceeding Australian National Health and Medical Research Council (NH&MRC) recommended limits. AusAUDIT had good internal consistency and discriminated significantly between persons meeting criteria for ICD-10 alcohol use disorders, and drinkers who did not. At currently recommended cut-off scores, AusAUDIT detected more than 85% of people meeting criteria for ICD-10 alcohol use disorders, or drinking over NH&MRC recommended limits, but its specificity was limited (29% in men, and 58% in women for drinking over NH&MRC limits). No subset of questions performed as well as the full AusAUDIT in detection of drinking problems, but the alcohol consumption items provided a reasonable screen for drinking over NH&MRC limits. We conclude that AusAUDIT is effective in detecting problematic drinking, but positive cases should be confirmed by clinical assessment. The findings illustrate the need for validation of questionnaire modifications, and the difficulty in increasing test sensitivity without reducing specificity.

The validity and heritability of self-report osteoarthritis in an Australian older twin sample

In order to investigate the genetic and environmental antecedents of osteoarthritis (CA), self-report measures of joint pain, stiffness and swelling were obtained from a population-based sample of 1242 twin pairs over 50 years of age. In order to provide validation for these self-report measures, a subsample of 118 twin pairs were examined according to the American College of Rheumatology clinical and radiographic criteria for the classification of osteoarthritis. A variety of statistical methods were employed to identify the model derived from self-report variables which would provide optimal prediction of these standardised assessments, and structural equation modelling was used to determine the relative influences of genetic and environmental influences on the development of osteoarthritis. Significant genetic effects were found to contribute to osteoarthritis of the hands, hips and knees in women, with heritability estimates ranging from 30-46% depending on the site. In addition, the additive genetic effects contributing to osteoarthritis in various parts of the body were confirmed to be the same. Statistically significant familial aggregation of osteoarthritis in men was also observed, but it was not possible to determine whether this was due to genetic or shared environmental effects.

Gene-Environment Interaction Effects on Behavioral Variation and Risk of Complex Disorders: The Example of Alcoholism and Other Psychiatric Disorders

There have been few replicated examples of genotype x environment interaction effects on behavioral variation or risk of psychiatric disorder. We review some of the factors that have made detection of genotype x environment interaction effects difficult, and show how genotype x shared environment interaction (GxSE) effects are commonly confounded with genetic parameters in data from twin pairs reared together. Historic data on twin pairs reared apart can in principle be used to estimate such GxSE effects, but have rarely been used for this purpose. We illustrate this using previously published data from the Swedish Adoption Twin Study of Aging (SATSA), which suggest that GxSE effects could account for as much as 25% of the total variance in risk of becoming a regular smoker. Since few separated twin pairs will be available for study in the future, we also consider methods for modifying variance components linkage analysis to allow for environmental interactions with linked loci.