Umeå University's logo

The WAA apheresis registry contains data on more than 140,000 apheresis procedures conducted in 12 different countries. The aim is to give an update of indications, type and number of procedures and adverse events (AEs).

Material and Methods: The WAA-registry is used for registration of apheresis procedures and is free of charge. The responsible person for a center can apply at the site www.waa-registry.org

Results: Data includes reported AEs from 2012 and various procedures and diagnoses during the years 2018–2022; the latter in total from 27 centers registered a total of 9500 patients (41% women) that began therapeutic apheresis (TA) during the period. A total of 58,355 apheresis procedures were performed. The mean age was 50 years (range 0–94). The most common apheresis procedure was stem cell collection for which multiple myeloma was the most frequent diagnosis (51%). Donor cell collection was done in 14% and plasma exchange (PEX) in 28% of patients; In relation to all performed procedures PEX, using a centrifuge (35%) and LDL-apheresis (20%) were the most common. The main indication for PEX was TTP (17%). Peripheral veins were used in 56% as the vascular access. The preferred anticoagulant was ACD. AEs occurred in 2.7% of all procedures and were mostly mild (1%) and moderate 1.5% (needed supportive medication) and, only rarely, severe (0.15%).

Conclusion: The data showed a wide range of indications and variability in apheresis procedures with low AE frequency.

Background and objectives: Citrate-based anticoagulation reduces plasma potassium and free magnesium in patients undergoing peripheral stem cell collections. Whether the effects may be mitigated by pre-procedure oral electrolyte supplements has not been previously assessed.

Materials and methods: Results from a historic cohort (2010-2013) guided a systematic prospective intervention in subjects deemed at risk for clinically meaningful hypokalaemia and hypomagnesaemia. From 2015 to 2019, 136 patients were enrolled in the study. Pre- and post-apheresis electrolyte levels were measured, and oral potassium and magnesium supplements were systematically administered based on the pre- electrolyte levels.

Results: We saw a 37% absolute reduction in severe hypokalaemia and 39% absolute reduction in hypomagnesaemia in the prospective intervention cohort when compared to the historic cohort. Multivariate analyses indicated that part of the effect was due to the electrolyte intervention, while part of the effect likely stemmed from other procedure-related changes implemented during the study period.

Conclusion: Oral potassium and magnesium prophylaxis appear to reduce hypokalaemia and hypomagnesaemia following peripheral stem cell collection. Whether the effect size is sufficient to motivate the intervention warrants further investigation, preferably in a prospective randomized trial setting.

Background: Blood donation is associated with a number of adverse events. Most of these are both uncommon and non-severe, leading to mild discomfort for the donor at worst. However, adverse events occurring outside of the donation facility have largely not been studied. In this study, we aim to further the understanding by performing the first large-scale analysis of short-term risks following whole blood donation.

Methods: We set up a nationwide cohort of donors who donated whole blood between 1987 and 2018. Analyses were conducted using conditional logistic regression in a self-comparison design, where each donor was compared only to themselves, considering the 30-day risk of 16 outcomes following whole blood donation. Outcomes included cardiac/vascular diseases such as myocardial infarction, unspecified conditions such as fainting, accidents or external causes of injury, and death.

Results: A total of 963,311 donors were included, 19,670 of whom experienced at least one of the outcomes within 30 days of a blood donation. For fainting and hypotonia we observed transient 2 to 5-fold risk increases on the day of donation and the subsequent 2–3 days. Importantly, the risk increase for the most pronounced effect corresponded to less than 1 additional events of fainting per 200,000 blood donations. Risks of all other outcomes were either unaffected or lower than expected right after blood donation.

Discussion: To conclude, we found no evidence of new or unexpected short-term health effects after blood donation and confirmed that risks of hypotension-related events requiring hospital care are present but small.

Extracorporeal photopheresis (ECP) is one of the most used and established therapies for steroid-refractory graft-vs-host disease (GvHD), with a good effect to side effect profile. In this review, we present a summary of present literature and provide evidence-based treatment guidelines for ECP in GvHD. The guidelines constitute a consensus statement formed by the Nordic ECP Quality Group representing all ECP centres in the Nordic countries, and aims to facilitate harmonisation and evidence-based practice. In developing the guidelines, we firstly conducted a thorough literature search of original articles and existing guidelines. In total, we identified 26 studies for ECP use in acute GvHD and 36 in chronic GvHD. The studies were generally small, retrospective and heterogeneous regarding patient characteristics, treatment schedule and outcome assessment. In general, a majority of patients achieved partial response or better, but response rates varied by the organs affected. Head-to-head comparisons to other treatment modalities were lacking. Overall, we consider the quality of evidence to be low-moderate (GRADE) and encourage future prospective multi-armed trials to strengthen the present recommendations. However, despite limitations in evidence strength, standardised treatment schedules and regular follow-up are imperative to ensure the best possible patient outcome.

BACKGROUND AND OBJECTIVES: Red-blood-cells (RBCs) undergo structural and metabolic changes with prolonged storage, which ultimately may decrease their survival after transfusion. Although the storage-induced damage to RBCs has been rather well described biochemically, little is known about the mechanisms underlying the recognition and rapid clearance of the damaged cells by macrophages.

MATERIALS AND METHODS: We, here, used a murine model for cold (+4°C) RBC storage and transfusion. Phagocytosis of human or murine RBCs, liquid stored for 6-8 weeks or 10-14 days, respectively, was investigated in murine peritoneal macrophages.

RESULTS: The effects of storage on murine RBCs resembled that described for stored human RBCs with regard to decreased adenosine triphosphate (ATP) levels, accumulation of microparticles (MPs) during storage, and RBC recovery kinetics after transfusion. Under serum-free conditions, phagocytosis of stored human or murine RBCs in vitro was reduced by 70-75%, as compared with that in the presence of heat-inactivated fetal calf serum (FCS). Human serum promoted phagocytosis of stored human RBCs similar to that seen with FCS. By adding fucoidan or dextran sulphate (blockers of scavenger receptors class A (SR-A)), phagocytosis of human or murine RBCs was reduced by more than 90%. Phagocytosis of stored human RBCs was also sensitive to inhibition by the phosphatidylinositol 3 kinase-inhibitor LY294002, the ERK1/2-inhibitor PD98059, or the p38 MAPK-inhibitor SB203580.

CONCLUSION: RBCs damaged during liquid storage may be recognized by macrophage SR-A and serum-dependent mechanisms. This species-independent recognition mechanism may help to further understand the rapid clearance of stored RBCs shortly after transfusion.

We aimed to examine whether the 9+ screening test score could predict injuries in elite floorball players. Eighty‐four elite floorball players participated in the study. At baseline, two physiotherapists assessed the participants using the 9+ screening test. The test score reflects strength, stability, mobility, and functional movement pattern with an emphasis on the lower body and core. Injuries that occurred the following season (2013/2014) were recorded by medical staff, coaches and/or self‐reported by the players. Overall, there was no relationship between the 9+ screening test score and injury risk (OR = 0.96 per SD lower test score, p = 0.84). We therefore conclude that the 9+ screening test is not suited for overall injury risk prediction in elite floorball players. Whether the test may be used to predict risk of certain injury types more strongly related to inadequate mobility and strength (e.g. muscle ruptures or strains) warrants further investigation.

Background and objectives: Symptomatic hypocalcaemia is common during apheresis procedures based on citrate‐based anticoagulants. As a consequence, patients often receive prophylactic calcium treatment. However, a recent publication based on the World Apheresis Association (WAA) register suggested harmful effects of such prophylactic calcium use. Recognizing possible limitations in the previous WAA register analyses, we critically re‐evaluate the data, to test whether a change in prophylactic calcium usage may be warranted.

Materials and methods: Using the WAA register, we reanalysed previous data by means of centre and treatment type stratification, to explore the role of prophylactic calcium as a risk factor for adverse events.

Results: There was large variability in adverse event rates dependent on the centre performing the apheresis procedure and dependent on the type of procedure. When this variability was accounted for, there was no clear effect of calcium administration on risk of adverse effects.

Conclusion: Shortcomings in the previous WAA register analyses may have failed to account for important confounding factors resulting in a substantial overestimation of the risk attributable to calcium usage. Overall our findings do not support a negative effect of prophylactic calcium administration in the apheresis setting.

BACKGROUND: Hematocrit is an independent predictor of cardiovascular risk in middle and old age, but whether hematocrit is also a predictor at younger ages is presently not known. In this study, we examined whether hematocrit measured in adolescence was associated with the risk of myocardial infarction later in life. METHODS: During Swedish national conscription tests conducted between 1969 and 1978, the hematocrit was measured in 417,099 young Swedish men. The cohort was followed for subsequent myocardial infarction events through December 2010. Associations between hematocrit and myocardial infarction were accessed using Cox regression models. RESULTS: During a median follow-up period of 36years, 9322 first-time myocardial infarctions occurred within the study cohort. After adjusting for relevant confounders and potential risk factors for myocardial infarction, men with a hematocrit≥49% had a 1.4-fold increased risk of myocardial infarction compared with men with a hematocrit≤44%. This relationship was dose dependent (p<0.001 for trend) and remained consistent throughout the follow-up period. CONCLUSIONS: In this cohort of young Swedish men, hematocrit was associated with the risk of myocardial infarction later in life after controlling for other coronary risk factors. The study findings indicate that hematocrit may aid future risk assessments in young individuals.

Background: There is evidence that atherosclerosis begins in childhood. There is also evidence that inflammatory markers measured in middle and old age predict risks of cardiovascular disease. In this report, we test whether an inflammatory marker measured in young adult men is associated with risk of myocardial infarction in middle age.

Methods: During Swedish national conscription tests from 1969 through 1978, the erythrocyte sedimentation rate, as a measure of inflammation, was measured in 433,577 young Swedish men. The cohort was observed for subsequent myocardial infarction events through December 2009.

Results: During an average follow-up time of 35 years, a total of 8,081 first-time myocardial infarctions occurred within the cohort. After adjustments for potential confounders and known risk factors for myocardial infarction, men with an elevated erythrocyte sedimentation rate (≥15 mm/h) had a 1.7 times increased risk of myocardial infarction during follow-up (95% CI 1.4-2.1) compared with men with an erythrocyte sedimentation rate of 1 mm/h. This relationship was dose dependent for each unit increase in erythrocyte sedimentation rate (P for trend <.001).

Conclusions: In this cohort of young Swedish men, the erythrocyte sedimentation rate was associated with risk of myocardial infarction 35 years later after control of the available data on other coronary risk factors. These data add important relevant information to the existing evidence that atherosclerosis begins in childhood.

BACKGROUND: body mass index is used widely to define overweight and obesity. Both high and low body mass indices are associated with increased mortality risk during middle age, but the relationship is less clear in later life. Thus, studies on the relationships between other aspects of body composition and mortality among older subjects are needed.

OBJECTIVE: to investigate associations between different aspects of body composition and mortality in older people.

METHODS: the study population comprised 921 participants aged ≥65 years who underwent dual-energy X-ray (DXA) absorptiometric examination at the Sports Medicine Unit, Umeå University. The main reason for admission was clinical suspicion of osteoporosis. Total, abdominal and gynoid fat masses and lean body mass were measured by DXA absorptiometry at baseline, and the cohort was followed (mean duration, 9.2 years) for mortality events.

RESULTS: during follow-up, 397 participants died. Lean mass was associated negatively with mortality in men and women (P < 0.001). Total fat mass showed a U-shaped association with mortality in men (P < 0.01) and a negative association in women (P < 0.01). A higher ratio of abdominal to gynoid fat mass increased mortality risk in women (P = 0.04), but not in men (P = 0.91).

CONCLUSIONS: lean mass is associated strongly with survival in older subjects. Greater fat mass is protective in older women, whereas very low or very high fat mass increases the risk of death in men. Further research is needed to better understand the mechanisms underlying these associations.