Abdominal aortic aneurysm (AAA) rupture is a common cause of death in adults. Current AAA treatment is by open surgical or endovascular aneurysm repair. Rodent model and human epidemiology, and genetic and observational studies over the last few decades have highlighted the potential of a number of drug therapies, including medications that lower blood pressure, correct dyslipidaemia, or inhibit thrombosis, inflammation or matrix remodelling, as approaches to managing small AAA. This review summarizes prior AAA pathogenesis data from animal and human studies aimed at identifying targets for the development of drug therapies. The review also systematically assesses past randomized placebo-controlled drug trials in patients with small AAAs. Eleven previously published randomized-controlled clinical trials testing different drug therapies aimed at slowing AAA progression were identified. Five of the trials tested antibiotics and three trials assessed medications that lower blood pressure. Meta-analyses of these trials suggested that neither of these approaches limit AAA growth. Allocation to blood pressure-lowering medication was associated with a small reduction in AAA rupture or repair, compared to placebo (relative risk 0.94, 95% confidence intervals 0.89, 1.00, P = 0.047). Three further trials assessed the effect of a mast cell inhibitor, fibrate or platelet aggregation inhibition and reported no effect on AAA growth or clinical events. Past trials were noted to have a number of design issues, particularly small sample sizes and limited follow-up. Much larger trials are needed to properly test potential therapeutic approaches if a convincingly effective medical therapy for AAA is to be identified.
Mendelian randomisation (MR) has been suggested to be able to overcome biases of observational studies, but no meta-analysis is available on MR studies on abdominal aortic aneurysm (AAA). This systematic review and Meta-analysis examined the evidence of causal risk factors for AAA identified in MR studies.
This study estimated the incidence of major amputation for people in North Queensland, Australia, examined changes in amputation rates over time and investigated survival after major amputation.
Abstract Aim To examine the efficacy of hyperbaric oxygen therapy in healing diabetes‐related lower limb ulcers through a meta‐analysis of randomized clinical trials. Methods A literature search was conducted to identify appropriate clinical trials. Inclusion required randomized study design and reporting of the proportion of diabetes‐related lower limb ulcers that healed. A meta‐analysis was performed to examine the effect of hyperbaric oxygen therapy on ulcer healing. The secondary outcomes were minor and major amputations. Results Nine randomized trials involving 585 participants were included. People allocated to hyperbaric oxygen therapy were more likely to have complete ulcer healing (relative risk 1.95, 95% CI 1.51–2.52; P <0.001), and less likely to require major (relative risk 0.54, 95% CI 0.36–0.81; P =0.003) or minor (relative risk 0.68, 95% CI 0.48–0.98; P =0.040) amputations than control groups. Sensitivity analyses suggested the findings were dependent on the inclusion of one trial. Adverse events included ear barotrauma and a seizure. Many of the trials were noted to have methodological weaknesses including absence of blinding of outcome assessors, lack of a justifiable sample size calculation and limited follow‐up. Conclusions This meta‐analysis suggests hyperbaric oxygen therapy improves the healing of diabetes‐related lower limb ulcers and reduces the requirement for amputation. Confidence in these results is limited by significant design weaknesses of previous trials and inconsistent findings. A more rigorous assessment of the efficacy of hyperbaric the efficacy of hyperbaric oxygen therapy is needed.