Natural history and clinical characteristics of inhibitors in previously treated haemophilia A patients: a case series

BACKGROUND

Development of inhibitors is the most serious complication in haemophilia A treatment. The assessment of risk for inhibitor formation in new or modified factor concentrates is traditionally performed in previously treated patients (PTPs). However, evidence on risk factors for and natural history of inhibitors has been generated mostly in previously untreated patients (PUPs). The purpose of this study was to examine cases of de novo inhibitors in PTPs reported in the scientific literature and to the EUropean HAemophilia Safety Surveillance (EUHASS) programme, and explore determinants and course of inhibitor development.

METHODS

We used a case series study design and developed a case report form to collect patient level data; including detection, inhibitor course, treatment, factor VIII products used and events that may trigger inhibitor development (surgery, vaccination, immune disorders, malignancy, product switch).

RESULTS

We identified 19 publications that reported 38 inhibitor cases and 45 cases from 31 EUHASS centres. Individual patient data were collected for 55/83 (66%) inhibitor cases out of 12 330 patients. The median (range) peak inhibitor titre was 4.4 (0.5-135.0), the proportion of transient inhibitors was 33% and only two cases of 12 undergoing immune tolerance induction failed this treatment. In the two months before inhibitor development, surgery was reported in nine (22%) cases, and high intensity treatment periods reported in seven (17%) cases.

CONCLUSIONS

By studying the largest cohort of inhibitor development in PTPs assembled to date, we showed that inhibitor development in PTPs, is on average, a milder event than in PUPs.

Recommendations for authors of manuscripts reporting inhibitor cases developed in previously treated patients with hemophilia: communication from the SSC of the ISTH

Aim The scope of this recommendation is to provide guidance for reporting of inhibitor cases in previously treated patients (PTPs) with hemophilia A. This guidance is intended to improve transparency and completeness of reporting of observed events; it does not cover planning, executing or analyzing original studies aimed at the assessment of inhibitor rates. Recommendation We recommend that for each case of inhibitor development reported in a published paper, a paragraph or a table is included in the main publication reporting as a minimum the underlined data fields in Table . We recommend transparent reporting when any of the suggested information is not available. We recommend that particular care is used in reporting the timeline of events by clearly identifying a reference time-point. We suggest that journals in the field adopt this guidance as instructions for the authors and as a guide for reviewers. Conclusion Development of inhibitors in PTPs is a very rare event. Standardized reporting of inhibitor characteristics will contribute to generating a body of evidence otherwise not available. Case by case reporting of the recommended data elements may shed light on the natural history and risk factors of inhibitor development in PTPs and be useful for tailoring care in similar future cases.

A qualitative analysis of women's satisfaction with primary care from a panel of focus groups in the National Centers of Excellence in Women's Health

Health issues unique to women and differences in healthcare experiences have recently gained attention as health plans and systems seek to extend and improve health promotion and disease prevention in the population. Successful efforts focused on enhancing quality of care will require information from the patient's perspective on how to improve such services to best support women's attempts to lead healthy and productive lives. The National Centers of Excellence in Women's Health program (CoE), sponsored by the Office on Women's Health within the Department of Health and Human Services, is based on an integrated model uniting research, training, healthcare, and community education and outreach. To examine women's concept and definitions of healthcare quality, 18 focus groups comprising 137 women were conducted nationwide on experiences and attributes of healthcare that women value in primary care. Following the focus groups, a woman-focused healthcare satisfaction instrument was developed for the purpose of assessing and improving healthcare delivery. We describe the qualitative results of the focus group study.