M. Barry

The effect of vitamin D supplementation on arterial stiffness in an elderly community–based population

Vitamin D deficiency may lead to impaired vascular function and abnormalities in central arterial stiffness. We compared the effects of two different doses of vitamin D3 on arterial stiffness in an elderly population with deficient serum 25-hydroxy-vitamin D levels. A total of 119 known vitamin D deficient (<50 nmol/L) subjects were randomized to receive either 50,000 international units (IU) or 100,000 IU single intramuscular vitamin D3. In the group that received 100,000 IU vitamin D, median pulse wave velocity decreased from 12.2 m/s (range, 5.1-40.3 m/s) to 11.59 m/s (range, 4.3-14.9 m/s) after 8 weeks (P = .22). A mean decrease of 3.803 ± 1.7 (P = .032) in augmentation index (a measure of systemic stiffness) was noted. Only 3/51 (5.8%) who received 100,000 IU vitamin D reached levels of sufficiency (>75 nmol/L). A significant decrease in augmentation index was seen in the group that received 100,000 IU vitamin D. Serum levels of 25-hydroxy-vitamin D were still deficient at 8 weeks in the majority of patients, which may be attributable to impaired bioavailability.

Repeatability of the measurement of aortic pulse wave velocity (aPWV) in the clinical assessment of arterial stiffness in community-dwelling older patients using the Vicorder® device

Abstract Background. Pulse wave velocity measured using the Vicorder® apparatus is a non-invasive indicator of arterial stiffness. The objective of this study was to assess its repeatability in older patients when used by medical professionals with limited experience of the technique. Methods. Aortic pulse wave velocity (aPWV) was measured using the Vicorder® system four times using the conventional pathway and twice by adapted pathway in 25 consecutive ambulant patients (15 male) after they rested supine for 15 min. A nurse and a doctor independently and alternately measured PWV using the same equipment and were blinded to their colleagues PWV readings. ‘Within’ and ‘between’ observer differences were assessed using intra-class correlation coefficients (rI) and 95% limits of agreement (95% LoA) derived from Bland-Altman plots. Results. Mean age was 79.8 (mean blood pressure [BP] = 133/69, Mean heart rate [HR]: 70.9). Mean PWV was 11.73 (Standard Deviation [SD] 2.6–3.6). ‘Between’ and ‘within’ observer repeatability was high, with rIs ranging from 0.8–0.93. The repeatability index for ‘between’ nurse and doctor measures was slightly lower (rI = 0.88) when an adapted cuff measure was used in assessing PWV compared to conventional cuff measures (rI = 0.93). Mean PWV readings ‘between’ observers differed by only 0.094 (95% CI −0.24 to 1.59). Conclusion. When undertaken by operators with limited previous technical experience, both ‘within’ and ‘between’ observer repeatability of PWV measurement was high. This method has the potential to be included in the clinical assessment of arterial stiffness in older ambulant patients.

PHP135 Evaluation of Cost Containment Interventions Introduced on the Community Drug Schemes in Ireland Using A National Prescrption Claims Database

PHP135 EVALUATION OF COST CONTAINMENT INTERVENTIONS INTRODUCED ON THE COMMUNITY DRUG SCHEMES IN IRELAND USING A NATIONAL PRESCRPTION CLAIMS DATABASE Usher C1, Tilson L1, Bennett K2, Barry M1 1National Centre for Pharmacoeconomics, Dublin, Ireland, 2Trinity Centre for Health Sciences, Dublin, Ireland OBJECTIVES: The aim of this paper was to examine trends in expenditure of pharmaceuticals on the community drug schemes from 2005 to 2010, during which time a range of cost-containment interventions were introduced which affected the pricing mechanism for pharmaceuticals in Ireland. METHODS: Data were analysed using a national prescription claims database according to drug class, i.e. generic, patent and off-patent for the two largest schemes; the General Medical Scheme (GMS) and Drug Payment (DP) scheme. Segmented regression was used to analyse the effects of the interventions on expenditure. RESULTS: An increase in expenditure was noted across all schemes up to 2009 and declined thereafter to the end of the study period (October 2010). Significant reductions in expenditure were noted following the introduction of a 20% price-cut to patent-expired products (off-patents) (p 0.001). In July 2009, pharmacy and wholesale margins were reduced, resulting in significant reductions in expenditure for patented (GMS; p 0.05 and DP scheme; p 0.001) and generic (DP scheme only; p 0.01) products. No significant reductions in expenditure were noted for off-patent products at this time. Furthermore, no significant reductions in expenditure were noted for off-patents following a 15% price reduction in January 2009 and a further 40% price reduction in February 2010. CONCLUSIONS: Results from the study indicate that reductions in the wholesale margin and pharmacy mark-up had the largest impact on reducing pharmaceutical expenditure during the study period. This analysis of national expenditure trends over a six-year period provides valuable information for the healthcare payer on the impact of the cost-containment interventions and may provide a benchmark for future negotiations with the pharmaceutical industry.