Peter R. Lewis

Air pollution and daily mortality in Sydney, Australia, 1989 through 1993.

OBJECTIVES This study examined the effects of outdoor air pollutants in Sydney, Australia, on daily mortality. METHODS Time-series analysis was performed on counts of daily mortality and major outdoor air pollutants (particulates, ozone, and nitrogen dioxide) in Sydney (1989 to 1993) with adjustment for seasonal and cyclical factors. Poisson regression was calculated with allowance for overdispersion and autocorrelation. The effects of lagging exposure by 0 to 2 days were assessed with single- and multiple-pollutant models. RESULTS An increase in daily mean particulate concentration from the 10th to the 90th centile was associated with an increase of 2.63% (95% confidence interval 0.87 to 4.41) in all-cause mortality and 2.68% (0.25 to 5.16) in cardiovascular mortality. An increase in daily maximum 1-hour ozone concentration from the 10th to the 90th centile was associated with an increase of 2.04% (0.37 to 3.73) in all-cause mortality and 2.52% (-0.25 to 5.38) in cardiovascular mortality. An increase in the daily mean nitrogen dioxide concentration from the 10th to the 90th centile was associated with an increase of 7.71% (-0.34 to 16.40) in respiratory mortality. Multiple-pollutant models suggest that the effects of particulates and ozone on all-cause and cardiovascular mortality, and of nitrogen dioxide on respiratory mortality, are independent of the effects of the other pollutants. CONCLUSIONS Current levels of air pollution in Sydney are associated with daily mortality.

Folate Nutritional Genetics and Risk for Hypertension in an Elderly Population Sample

Background/Aims: 118 elderly participants (65–90 years) were assessed for any relationship between folate, related genes and hypertension. Methods: Six B-vitamin-related SNPs were genotyped in 80 normotensive and 38 hypertensive subjects. Results: Of six polymorphisms (677C>T-MTHFR, 1298A>C-MTHFR, 80G>A-RFC, 2756A>G-MS, 66A>G- MSR, 19bpDHFR and 1561C>T-GCPII), only 677C>T-MTHFR was a significant risk for hypertension: OR 1.89; 95% CI 1.07–3.32 (χ2 p = 0.038). Additionally, hypertensive subjects had a significantly lower intake of dietary folate than normotensive individuals (p = 0.0221), although this did not markedly alter blood metabolite levels. Several significant linear associations between dietary folate and related blood metabolites were found in normotensive subjects (p < 0.001 for Hcy, red cell and serum folate) and were as predicted on an a priori basis – generally weaker associations existed in hypertensive subjects (p < 0.05 for serum folate). This was true for data examined collectively or by genotype. Multiple-regression analysis for diastolic or systolic blood pressure showed significant interaction for gender and folate intake (p = 0.014 and 0.019, respectively). In both cases this interaction occurred only in females, with higher folate intake associated with decreased blood pressure. Regressing diastolic blood pressure and 677C>T-MTHFR genotype showed significance (males; p = 0.032) and borderline significance (all subjects). Conclusion: Dietary folate and 677C>T-MTHFR genotype may modify blood pressure.

Preliminary Evidence for Genetic Selection of 677T-MTHFR by Natural Annual Cycle of Folate Abundance

Background/Aims: Folic acid mediates transfer of one-carbon units into methionine and DNA-thymine biosynthesis. Discretionary and mandatory use of synthetic folic acid (SFA) to reduce spina bifida is on the increase. We show that historically, the seasonal cycle of abundance of folate-rich foods may have regulated embryo viability by acting as a selection factor for a significant polymorphism within a gene encoding 5,10-methylenetetrahydrofolate reductase (677C→T-MTHFR). Methods: Blood was collected from 150 UK and 118 Australian subjects born prior to discretionary or mandatory use of SFA. 677C→T-MTHFR genotype was determined using PCR. Results: The highest prevalence for 677T-MTHFR occurred 9 months post-harvest in UK subjects and was significantly higher at this time of year (July–Sept.) compared with Jan.-Mar. (OR = 2.0, 95% CI 1.03–3.87, p = 0.039) and Oct.–Dec. (OR = 2.2, 95% CI 1.12–4.31, p = 0.021). This effect was not detected in an Australian population subject to more moderate seasonality. Conclusions: Dietary folate may confer significant genetic buffering within populations dependent upon seasonal food sources that modify an individual’s vitamin status at the time of conception.

Evaluating the efficacy of vaccine storage in the general practice setting.

Objectives: To describe the implementation of guidelines for vaccine storage in general practice, and their effectiveness in achieving optimum vaccine storage temperatures in fridges.

Influenza and pneumococcal vaccination: do older people know if they have been vaccinated?

Objective: To estimate influenza and pneumococcal immunisation rates by self‐report and validate this with immunisation providers.

Retirement Health and Lifestyle Study: Australian Neighborhood Environments and Physical Activity in Older Adults:

The aim of this study was to compare the walkability of neighborhood environments of older adults (65 years and above) living in the general community and retirement village settings, and to describe associations between walkability and the physical activity of participants. The study was conducted in a coastal region of Australia largely characterized by urban sprawl. In 2011-2012, 292 participant neighborhoods (400 m radius around each home) were audited using the Irvine-Minnesota Inventory. Having validated a local adaptation of this tool, we compared neighborhood environments in the two settings. We found no association between walkability of the built environment and walking behavior of participants. Although retirement village residents lived in more highly walkable environments, they did not walk more and their overall levels of physical activity were lower than those of community residents.