Consequences of switching from prophylactic treatment to on-demand treatment in late teens and early adults with severe haemophilia A: the TEEN/TWEN study

Although many people with haemophilia discontinue prophylaxis in their late teens or early adulthood, the consequences of this decision are largely not known. This 18-month, observational, case-controlled, multicentre study evaluated long-term prophylaxis and the consequences of switching from prophylaxis to on-demand treatment in late teens and young adults with severe haemophilia A. Participants with haemophilia (aged 14-29 years) on prophylaxis ≥ 60% of the time for the 5 years before study entry were enrolled into 1 of 2 prospective or 1 retrospective group. Group 1 was prophylaxis, group 2 had voluntarily discontinued prophylaxis ≤ 12 months before study entry and group 3 had voluntarily discontinued prophylaxis ≥ 13 months before study entry. Assessments included bleeding frequency (primary endpoint), Haemo-QoL-A health-related quality of life (HRQoL) scores, Gilbert score, development of target joints, Haemophilia Activities List, Godin Leisure-Time, treatment satisfaction and State-Trait Anxiety Inventory (secondary and exploratory endpoints). Descriptive statistics were provided for all variables. Thirty-eight participants (group 1, n = 22; group 2, n = 5; group 3, n = 11; median age, 19.5 years) were enrolled. The median annualized number of bleeding events was 0, 4.8 and 24 in groups 1, 2 and 3 respectively. HRQoL was lower in participants who discontinued prophylaxis vs. those who remained on prophylaxis. Changes in the remaining secondary and exploratory variables were small, but were generally worse in participants who discontinued prophylaxis. Following a switch from prophylaxis to on-demand therapy, the number of bleeding events increased and HRQoL worsened in late teens and young adults with severe haemophilia A.

Parental age effects on cortical morphology in offspring

The age at which a parent has a child impacts the child's cognition and risk for mental illness. It appears that this risk is curvilinear, with both age extremes associated with lower intelligence and increased prevalence of some neuropsychiatric disorders. Little is known of the neural mechanisms underpinning this phenomenon. We extracted lobar volumes, surface areas, and cortical thickness from 489 neuroanatomic magnetic resonance images acquired on 171 youth. Using linear mixed model regression, we determined the association between parental age and offspring's neuroanatomy, adjusting for offspring's age, sex, intelligence, and parental socioeconomic class. For gray matter volumes, quadratic paternal and maternal age terms contributed significantly (maternal quadratic age effect: t = -2.2, P = 0.03; paternal quadratic age effect: t = -2.4, P = 0.02) delineating an inverted "U" relationship between parental age and gray matter volume. Cortical volume increased with both advancing paternal and maternal age until around the early 30s after which it fell. Paternal age effects were more pronounced on cortical surface area, whereas maternal age impacted more on cortical thickness. There were no significant effects of parental age on white matter volumes. These parental age effects on cerebral morphology may form part of the link between parental age extremes and suboptimal neurocognitive outcomes.

Elastic contact mechanics: percolation of the contact area and fluid squeeze-out

The dynamics of fluid flow at the interface between elastic solids with rough surfaces depends sensitively on the area of real contact, in particular close to the percolation threshold, where an irregular network of narrow flow channels prevails. In this paper, numerical simulation and experimental results for the contact between elastic solids with isotropic and anisotropic surface roughness are compared with the predictions of a theory based on the Persson contact mechanics theory and the Bruggeman effective medium theory. The theory predictions are in good agreement with the experimental and numerical simulation results and the (small) deviation can be understood as a finite-size effect. The fluid squeeze-out at the interface between elastic solids with randomly rough surfaces is studied. We present results for such high contact pressures that the area of real contact percolates, giving rise to sealed-off domains with pressurized fluid at the interface. The theoretical predictions are compared to experimental data for a simple model system (a rubber block squeezed against a flat glass plate), and for prefilled syringes, where the rubber plunger stopper is lubricated by a high-viscosity silicon oil to ensure functionality of the delivery device. For the latter system we compare the breakloose (or static) friction, as a function of the time of stationary contact, to the theory prediction.

The use of a single von Willebrand factor-containing, plasma-derived FVIII product in hemophilia A immune tolerance induction: the US experience

BACKGROUND

Inhibitors are a serious complication for patients with severe hemophilia A. Immune tolerance induction (ITI) is the primary method for eradicating these inhibitors. The role of type of concentrate and in particular the use of von Willebrand factor-containing, plasma-derived factor VIII (VWF/pd-FVIII) concentrate in primary or rescue ITI remains unclear.

OBJECTIVES

To report retrospective collection of data on the use of a single VWF/pd-FVIII concentrate in primary and rescue ITI.

METHODS

Retrospective chart review of hemophilia A inhibitor patients at 11 US institutions who received VWF/pd-FVIII concentrate in primary or rescue ITI.

RESULTS

Primary ITI was carried out in eight inhibitor patients with a 75% complete and partial success. Secondary ITI was carried out in 25 inhibitor patients, with 52% attaining complete or partial success.

CONCLUSIONS

This report represents the largest group of primarily pediatric, high-titer inhibitor patients treated with a single VWF/pd-FVIII concentrate. It adds retrospective data to the use of VWF-containing plasma-derived factor VIII concentrate in primary and rescue ITI, particularly in those patients with characteristics of poor response to ITI.

Utilization patterns and associated costs of factor assistance programmes among persons with haemophilia: a single institution review

Although individuals with haemophilia have benefited from advances and the availability of safe, effective factor replacement products, high treatment costs and insurance coverage limits remains a significant concern among persons with this disease. Many uninsured haemophiliacs turn to emergency rooms for treatment and/or patient assistance programmes for treatment of a bleed or injury. However, neither of these options is a sustainable solution for managing the care of patients with this costly disease. This study was conducted to examine the use of factor assistance programmes and estimate annual amounts of factor dispensed by each programme along with their associated costs. Retrospective review of pharmacy and medical record of all patients who attended the Gulf States Hemophilia and Thrombophilia Center, and who were enrolled in any factor assistance programme(s) between January 2007 and December 2010 was performed. During the 4-year observation period, approximately 19% of the centre's haemophilia patient population was enrolled and received free factor products from at least one patient assistance programme. In addition, approximately 9.1 million dollars (US) worth of factor replacement therapy was donated to our patients during the study time. Although assistance programmes have helped many uninsured individuals with haemophilia to receive free factor products, they are not an enduring answer to the insurance problems many of our patients face. More effort needs to be focused on how to effectively manage uninsured persons with haemophilia to ensure that their health care and treatment needs are adequately met.

Relationship among maximal grip, throwing velocity and anthropometric parameters in elite water polo players

AIM

As independent aspects, body size, body composition, and physiological performance of elite athletes have aroused the interest of sports scientists but, unfortunately, studies that combine these aspects are scarcely avalaible in water polo. The aim of the present study was to: 1) to develop an anthropometric profile of highly skilled male Water Polo players, and 2) to identify significant relationships between these features and overhead throwing velocity in highly skilled male water polo players.

METHODS

Thirteen male water polo players, with a mean age of 26.10±4.82, were recruited from the Spanish Water Polo team and an anthropometric assessment on all of them was carried out. Throwing velocity was evaluated in three different situations from the 5 m-penalty line on the center of the water polo goal: A) throwing without a defender nor a goalkeeper; B) throwing with a goalkeeper only, and C) 3) armfuls running shot with goalkeeper. Maximal handgrip was also tested.

RESULTS

Biacromial breadth shows a significative correlation with hand grip in water polo players (r=0.792; P=0.001) and also correlates with Throwing velocity (r=0.716; P<0.001). Biepicondylar femur breadth correlates significatively with hand grip (r=0.727; P<0.05) and also with throwing velocity in "throwing with goalkeeper" situation (r=0.664; P<0.05). Hand grip shows a significant correlation with throwing velocity in "throwing with goalkeeper" situation (r=0.603; P<0.05).

CONCLUSION

In conclusion, body mass aspects are not related with throwing velocity in highly skilled Water Polo players. Maximal hand grip is related with throwing velocity in "throwing with goalkeeper" situation. More investigations about water polo are necessary.