Rate of inhibitor development in previously untreated hemophilia A patients treated with plasma-derived or recombinant factor VIII concentrates: a systematic review.

BACKGROUND: Different rates of inhibitor development after either plasma-derived (pdFVIII) or recombinant (rFVIII) FVIII have been suggested. However, conflicting results are reported in the literature. OBJECTIVES: To systematically review the incidence rates of inhibitor development in previously untreated patients (PUPs) with hemophilia A treated with either pdFVIII or rFVIII and to explore the influence of both study and patient characteristics. METHODS: Summary incidence rates (95% confidence interval) from all included studies for both pdFVIII and rFVIII results were recalculated and pooled. Sensitivity analysis was used to investigate the effect of study design, severity of disease and inhibitor characteristics. Meta-regression and analysis-of-variance were used to investigate the effect of covariates (testing frequency, follow-up duration and intensity of treatment). RESULTS: Two thousand and ninety-four patients (1965 treated with pdFVIII, 887 with rFVIII; median age, 9.6 months) from 24 studies were investigated and 420 patients were observed to develop inhibitors. Pooled incidence rate was 14.3% (10.4-19.4) for pdFVIII and 27.4% (23.6-31.5) for rFVIII; high responding inhibitor incidence rate was 9.3% (6.2-13.7) for pdFVIII and 17.4% (14.2-21.2) for rFVIII. In the multi-way anova study design, study period, testing frequency and median follow-up explained most of the variability, while the source of concentrate lost statistical significance. It was not possible to analyse the effect of intensity of treatment or trigger events such as surgery, and to completely exclude multiple reports of the same patient or changes of concentrate. CONCLUSIONS: These findings underscore the need for randomized controlled trials to address whether or not the risk of inhibitor in PUPs with hemophilia A differs between rFVIII and pdFVIII.

Diabetic microvascular complications: can patients at risk be identified? A review.

People with diabetes have an increased risk of developing microvascular complications, diabetic retinopathy, diabetic nephropathy and diabetic neuropathy, which, if undetected or left untreated, can have a devastating impact on quality of life and place a significant burden on health care costs. In addition, diabetic microvascular complications can reduce life expectancy. The strongest risk factors are glycaemic control and diabetes duration; however, other modifiable risk factors such as hypertension, hyperlipidaemia and smoking, and unmodifiable risk factors including age at onset of diabetes and genetic factors may all play a part. Along with the presence of external risk factors, some associations have also been noted between diabetic microvascular complications themselves. There is evidence that diabetic retinopathy in association with increased blood pressure is an important risk factor for diabetic nephropathy progression. Significant correlations have also been shown between the presence of diabetic peripheral neuropathy and the presence of background or proliferative diabetic retinopathy. Clinical trials are currently in progress looking at a number of approaches to designing treatments to prevent the adverse effects of hyperglycaemia. It is essential however, that risk factors associated with the progression and development of diabetic microvascular complications are detected and treated at an early stage in order to further reduce morbidity and mortality. Considering all three complications as interrelated may well facilitate early detection of microvascular disease. Despite good long-term glycaemic and blood pressure control, diabetes remains a major cause of blindness, renal failure and amputations. As the incidence of diabetes continues to rise, the burden of diabetic microvascular complications will increase in future, hence the need for early detection. Considering the microvascular complications of diabetes as related, and enquiring proactively about complications, may well facilitate early detection of microvascular disease.