Is hypovitaminosis D associated with abdominal aortic aneurysm, and is there a dose-response relationship?

OBJECTIVE: This study aims to investigate the association between plasma 25-hydroxyvitamin D (25(OH)D) concentrations with the presence of abdominal aortic aneurysm (AAA) and aortic diameter. DESIGN: An observational study of 4233 community-dwelling men aged 70-88 years, who participated in a randomised controlled trial of screening for AAA. METHODS: Infrarenal aortic diameter measured by ultrasound and 25(OH)D by immunoassay. RESULTS: A total of 311 men (7.4%) with AAA (defined as aortic diameter ≥ 30 mm) comprised the study. Multivariable models were adjusted for age, smoking, cardiovascular disease, hypertension, diabetes, dyslipidaemia, body mass index and serum creatinine concentration. Amongst men with the lowest 25(OH)D quartile of values compared with the highest quartile, the adjusted odds ratio of having an AAA increased in a graded fashion from 1.23 (95% confidence interval (CI) 0.87-1.73) for AAA ≥ 30 mm to 5.42 (95% CI 1.85-15.88) for AAA ≥ 40 mm. Similarly, there was a dose-response relationship between 25(OH)D concentrations and the size of the AAA: every 10-nmol l(-1) decrease in 25(OH)D levels was associated with 0.49 mm (95% CI 0.11-0.87) increase in mean aortic diameter. CONCLUSIONS: Low vitamin D status is associated with the presence of larger AAA in older men, and there is a graded inverse relationship between 25(OH)D concentrations and AAA diameter. Further research is needed to clarify the mechanisms underlying these associations.

Hip fractures among indigenous Western Australians from 1999 to 2009.

BACKGROUND: Minimal trauma hip fractures are prevalent in Australia. The incidence rate and trend of hip fractures in Indigenous Western Australians have not been formally reported. AIMS: To evaluate incidence rates and trend of minimal trauma hip fractures in Indigenous and other Western Australians aged 40 years and over in 1999-2009 METHODS: Hip fracture data were obtained from an administrative database for all hospitalisations in Western Australia. Age-standardised incidence rates were calculated using direct standardisation, and standardised rate ratios were calculated using the indirect method. Trend in incidence rates were calculated using Poisson regression. RESULTS: In 1999-2009, 11,844 admissions for minimal trauma hip fractures were reported among Western Australians aged 40 years and over, of which 201 were recorded as indigenous. The age-standardised hip fracture rate was 273.0 (95% confidence interval (CI) 230.7-315.4) per 100,000 person-years for indigenous adults and 148.8 (95% CI 146.1-151.5) per 100,000 person-years for non-indigenous adults. The standardised morbidity ratio was 2.2 (95% CI 1.9-2.5). Over this period, age-standardised rates increased by an average of 7.2% per year among indigenous adults (P = 0.006), whereas non-indigenous rates fell by an average of 3.4% per year (P < 0.001). The relatively higher rates among indigenous adults were more evident in the younger age groups. CONCLUSION: There is a widening gap in minimal trauma hip fracture rates between indigenous and other Western Australians. This study demonstrates a need for public health review and management strategies to reduce falls and hip fracture in the indigenous community.