Plasma retinol, carotene and vitamin E concentrations and lung function in a crocidolite-exposed cohort from Wittenoom, Western Australia: a cohort study

BACKGROUND: Increased rates of death from asbestos related diseases have been reported for people previously employed in the mining and milling operations at Wittenoom (Western Australia), and people who lived in the nearby town, where they were environmentally exposed to crocidolite. METHODS: Annual measurements of forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) and plasma concentrations of retinol, carotene and vitamin E have been made since 1992. Mixed effects models were used to examine the associations between lung function and the plasma vitamin levels of retinol, carotene and vitamin E. RESULTS: After adjusting for potential confounders, higher plasma retinol and carotene concentrations were significantly associated with higher levels of lung function at entry into the study, while vitamin E concentrations were associated with lower entry lung function. Retinol was associated with a less steep decline of lung function over time, while carotene concentrations were associated with an increased decline of lung function over time and vitamin E levels were not associated with changes of lung function over time. CONCLUSION: These results support a beneficial relationship between plasma concentrations of retinol on the levels and rates of change of lung function, while showing no such consistent beneficial effect for plasma levels of beta-carotene or vitamin E

Which women stop smoking during pregnancy and the effect on breastfeeding duration

BACKGROUND: Cigarette smoking during pregnancy increases the risk of adverse pregnancy outcomes and women who quit smoking at this time are able to reduce the risk of low birth weight, preterm labour, spontaneous abortion and perinatal death. This study investigates the socio-demographic characteristics of pregnant women who stop smoking during pregnancy and the association between stopping smoking and breastfeeding duration. METHODS: A 12 month longitudinal study was conducted in two public maternity hospitals in Perth, Australia between mid-September 2002 and mid-July 2003. While in hospital, participating mothers completed a self-administered baseline questionnaire. Follow up telephone interviews were conducted at 4, 10, 16, 22, 32, 40 and 52 weeks. RESULTS: A total of 587 (55%) mothers participated in the study. Two hundred and twenty six (39%) mothers reported smoking prior to pregnancy and 77 (34%) of these stopped smoking during pregnancy. Women who were pregnant for the first time were twice as likely (OR = 2.05; 95% CI 1.047 – 4.03; p < 0.05) to quit smoking as multiparous women. Women who smoked more than 10 cigarettes per day were significantly less likely to quit smoking during pregnancy (OR = 0.36; 95% CI 0.18 – 0.69; p < 0.05). Women who consumed alcohol before pregnancy were three times more likely to quit smoking (OR = 2.58; 95% CI 1.00 – 6.66; p < 0.05). Quitting smoking during pregnancy was significantly associated with breastfeeding for longer than six months (OR = 3.70; 95% CI 1.55 – 8.83; p < 0.05). CONCLUSION: Pregnancy is a time when many women are motivated to quit smoking and providing targeted smoking cessation interventions at this time, which take into account factors predictive of quitting smoking, are more likely to be successful

Thyroid hormones and depression: The health in men study

Context: Current practice guidelines suggest that thyroid function tests should be an integral part of the assessment of adults presenting with a depressive episode, although there is a paucity of data available to support such a recommendation. Objective: To determine if biochemical markers of thyroid dysfunction are associated with prevalent and incident clinically significant depressive symptoms. Design: Cross-sectional and cohort studies. Patients: Community-dwelling sample of 3,932 men age 69 to 87 free of overt thyroid disease. Main Outcome Measures: We used the 15-item Geriatric Depression Scale to ascertain the presence of prevalent clinically significant depressive symptoms, and the Western Australia Data Linkage System to establish the onset of a depressive episode according to the International Classification of Diseases. Results: The serum concentration of thyroid-stimulating hormone and free thyroxine (fT4) did not affect the odds of prevalent or the hazard of incident depression. The odds of prevalent depression were 0.8 (95% CI: = 0.5-1.3) for men with subclinical hypothyroidism and 1.4 (95% CI: = 0.3-5.8) for those with subclinical hyperthyroidism. The hazard ratio of incident depression associated with subclinical hypothyroidism was 0.7 (95% CI: = 0.3-1.9). No men with subclinical hyperthyroidism developed depression during the follow-up period of 5.5 ± 1.4 years. Conclusions: Subclinical thyroid disease is not associated with prevalent or incident depression in older men. These findings do not support the routine screening of subclinical thyroid dysfunction among older adults with depression. © 2011 American Association for Geriatric Psychiatry

The effect of alcohol on breastfeeding duration in Australian women

Aim: This study investigated the relationships between alcohol consumption and breastfeeding initiation and duration. Methods: Design and Setting: A 12-month longitudinal study was conducted in two public hospitals in Perth, Australia between September 2002 and July 2003. Intervention: Participating mothers completed a self-administered baseline questionnaire. Follow-up telephone interviews were conducted at 4, 10, 16, 22, 32, 40 and 52 weeks. Main outcome measures: Association of the relationships between alcohol consumption and breastfeeding initiation and duration. Results: After 6 months of follow-up, women who consumed alcohol at levels of more than two standard drinks per day were almost twice as likely to discontinue breastfeeding than women who drank below these levels (HR 1.9, 95% CI 1.1, 3.0). Conclusion: Consuming alcohol in excess of two standard drinks per day during lactation was found to be independently associated with shorter breastfeeding duration, even after consideration of previously identified predictors of breastfeeding duration. Guidelines that provide direction on safe alcohol consumption for lactating mothers may help support extended breastfeeding duration

Effect of NSAIDS and COX-2 inhibitors on the incidence and severity of asbestos-induced malignant mesothelioma: Evidence from an animal model and a human cohort

Objectives: Non-steroidal anti-inflammatory drugs (NSAIDs) and COX-2 inhibitors have been associated with lower incidence rates of some cancers. Because asbestos can cause chronic inflammation at the pleural and peritoneal surfaces we hypothesised that NSAID and COX-2 inhibitors would inhibit the development of asbestos-induced mesothelioma. Materials and methods: A murine model of asbestos-induced mesothelioma was used to test this hypothesis by providing the NSAID, aspirin, daily in the feed at 50. mg/kg or 250. mg/kg. In a parallel study, the relationship between the use of NSAID and COX-2 inhibitors and mesothelioma was investigated in a human cohort of 1738 asbestos exposed people living or working in Wittenoom, Western Australia (a crocidolite mine site). Results: Aspirin did not alter the rate of disease development or increase the length of time that mice survived. Aspirin had a small but significant effect on disease latency (the time between asbestos exposure and first evidence of disease; p &lt; 0.05) but disease progression was not affected by the continued presence of the drug. In the Wittenoom cohort, individuals who reported use of NSAIDs, COX-2 inhibitors or both did not have a lower incidence of mesothelioma (HR = 0.85; 95% CI = 0.53-1.37, p= 0.50), (HR = 0.69; 95% CI = 0.21-2.30, p= 0.55) and (HR = 0.43; 95% CI = 0.16-1.13, p= 0.087) respectively. Conclusion: We conclude that NSAIDs and COX-2 inhibitors do not moderate mesothelioma development or progression in a human cohort exposed to asbestos and this result is confirmed in an autochthonous mouse model