Packed Red Blood Cell Transfusion Causes Greater Hemoglobin Rise at a Lower Starting Hemoglobin in Patients with Subarachnoid Hemorrhage

Erythropoietin downregulates red blood cell clearance, increasing transfusion efficacy in severely anemic recipients

Red blood cells (RBC) transfusion is used to alleviate symptoms and prevent complications in anemic patients by restoring oxygen delivery to tissues. RBC transfusion efficacy, that can be measured by a rise in hemoglobin (Hb) concentration, is influenced by donor-, product-, and recipient-related characteristics. In some studies, severe pre-transfusion anemia is associated with a greater than expected Hb increment following transfusion but the biological mechanism underpinning this relationship remains poorly understood. We conducted a prospective study in critically ill patients and quantified Hb increment following one RBC transfusion. In a murine model, we investigated the possibility that, in conjunction with the host erythropoietic response, the persistence of transfused donor RBC is improved to maintain a highest RBC biomass. We confirmed a correlation between a greater Hb increment and a deeper pre-transfusion anemia in a cohort of 17 patients. In the mouse model, Hb increment and post-transfusion recovery were increased in anemic recipients. Post-transfusion RBC recovery was improved in hypoxic mice or those receiving an erythropoiesis-stimulating agent and decreased in those treated with erythropoietin (EPO)-neutralizing antibodies, suggesting that EPO signaling is necessary to observe this effect. Irradiated recipients also showed decreased post-transfusion RBC recovery. The EPO-induced post-transfusion RBC recovery improvement was abrogated in irradiated or in macrophage-depleted recipients, but maintained in splenectomized recipients, suggesting a mechanism requiring erythroid progenitors and macrophages, but which is not spleen-specific. Our study highlights a physiological role of EPO in downregulating post-transfusion RBC clearance, contributing to maintain a vital RBC biomass to rapidly cope with hypoxemia.

Iron status in patients with burn anaemia

PURPOSE

The iron status of burn patients is poorly understood, limited by difficulty interpreting conventional iron studies in the context of the acute phase response triggered by critical illness. The aim of this study was to evaluate the iron status of patients with burn anaemia using recent post-operative guidelines.

METHODOLOGY

This retrospective cohort study utilised data collected from records for adult patients admitted to the Royal Brisbane and Women's Hospital with burns to at least 15% TBSA. Rates of iron deficiency, defined as ferritin< 100 µg/L or ferritin 100-300 µg/L with transferrin saturation< 20%, and low iron availability, defined as transferrin saturation< 20%, were calculated.

RESULTS

Of 60 included patients (90% male), 16 (27%) underwent iron studies. 11 (18%) were treated with intravenous iron. Iron studies showed that five (31%) patients had evidence of iron deficiency, and ten out of 12 (83%) had evidence of reduced iron availability. Two patients (40%) with evidence of iron deficiency were not treated with intravenous iron.

CONCLUSION

Application of recent guidelines for interpretation of conventional iron studies in patients with inflammatory states may improve the identification of iron deficiency in burn patients. Iron deficiency may be an under-recognised and under-treated contributor to burn anaemia.

Thrombocytopenia as an Independent Prognostic Indicator Following Extradural Spinal Tumor Resection

BACKGROUND

Few studies have examined the prognosis for patients with baseline thrombocytopenia undergoing extradural spine tumor resection.

OBJECTIVE

To evaluate mortality, readmission, and other 30-day outcomes in patients with varying degrees of preoperative thrombocytopenia undergoing osseous extradural tumor excision.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) was queried from 2011-2019. Patients were categorized according to baseline preoperative platelet count, in 25,000/μL increments: 125,000-149,000/μL, 100,000-125,000/μL, 75,000-100,000/μL, and < 75,000/μL. These were compared to a control group with platelet count >150,000/μL. Outcomes in each cohort were analyzed using multivariate logistic regression analysis.

RESULTS

The database search revealed 3,574 patients undergoing extradural tumor resection; 2,171 (4.8%) of patients with platelets 125,000-149,000/μL, 114 (3.2%) with 100,000-125,000/μL, 75,000-100,000/μL in 43 (1.2%), and < 75,000/μL in 42 (1.2%). Platelet counts <100,000/μL was associated with perioperative blood transfusion, cardiac complications, and non-home discharge, and 30-day mortality. On subgroup analysis for mortality, an interaction was present between individuals with moderate/severe thrombocytopenia and cervical tumors.

CONCLUSION

In patients undergoing surgery for extradural spine tumor, degree of baseline thrombocytopenia-rather than presence alone-is an independent predictor of several adverse events. Wherever possible, optimization of preoperative platelet count to at least 100,000/μL may improve outcomes.

Impact of blood donor characteristics on quality of packed red blood cell concentrates

INTRODUCTION

Impact of blood donor characteristics on quality of packed red blood cell concentrates.

OBJECTIVE

To determine the impact of donor factors on the quality of packed red blood cell concentrates.

MATERIAL AND METHODS

The analytical cross sectional study was conducted on 505 whole blood donors after approval by the Institutional Ethics Committee and written informed consent from blood donors. Two mL EDTA sample was collected for pre-donation haemoglobin estimation and all relevant donor details were recorded. Whole blood was collected in 350mL double blood bags. PRBCs were prepared as per the departmental SOP. Volume of each PRBC was recorded and sample from each bag was taken for estimation of total haemoglobin content and haematocrit.

RESULTS

Of 505 blood donors, 459 (90.9%) were males and 324 donors (64.2%) were less than 30 years of age. The majority of the donors were repeat donors (61%, n=308 repeat donors), vegetarians (52.9%, n=267 vegetarians) and non-smokers (92.7%, n=468). Mean haemoglobin was found to be significantly higher in males (14.9 vs. 13.3; P≤0.001), donors more than 30 years of age (15 vs. 14.7; P=0.042), repeat donors (14.9 vs. 14.7), non-vegetarians (15.1 vs. 14.6; P≤0.001) and smokers (15.3 vs. 14.8g/dL; P=0.020). PRBC units prepared from male blood donors, repeat donors and non vegetarians had significantly higher mean volume and mean total haemoglobin content. Strong positive correlation was observed between haemoglobin of the blood donor and total haemoglobin content of the PRBC and volume of blood collected.

CONCLUSIONS

Donor characteristics do have effect on total haemoglobin content of packed red blood cells.

A comparative analysis of factors influencing haemoglobin content in RBC units

BACKGROUND AND OBJECTIVES

The increment in a patient's haemoglobin level is based upon the haemoglobin content of the transfused RBC units. The total haemoglobin present in the blood bags can vary because of the blood donor, processing method, volume and type of bag used. The study is done to analyse the factors causing variation of haemoglobin content in RBC units.

MATERIALS AND METHODS

A total of 260 RBC units were tested for the haemoglobin content and analysed with the donor variables (age, gender, weight & capillary haemoglobin). The blood bags were then separated into two groups based on the donor capillary haemoglobin (normal 12.5-15.0 g/dL vs high 15.1-18.0 g/dL), volume (350 vs 450 mL), processing method (Platelet rich plasma vs buffy coat) and further analysis was carried out.

RESULTS

The mean haemoglobin content was 54.7 g ranging from 34.2-80 g per unit. The factors which significantly influenced (p < 0.0001) were capillary haemoglobin, gender and weight of donor, volume of blood collected and the processing method. There was a significant difference (p < 0.0001) in haemoglobin content between the two groups in all the three categories (capillary haemoglobin, volume and processing method). Regression analysis showed all three of them contributed to 80 % variability of haemoglobin content in the RBC unit.

CONCLUSION

The marked variation of haemoglobin content in our study revealed that there is a need for standardizing RBC unit. Labelling of units with haemoglobin content and transfusion based on it will result in better patient care.

Indian blood donor selection guidelines: Review in the context of the ongoing COVID-19 pandemic

The National Blood Transfusion Services under the aegis of the ministry of health and family welfare, India has recently issued guidelines regarding the blood donor selection criteria and the processing of blood. Care has been taken to make the blood transfusions safer. However, COVID-19 has disrupted the organization of the voluntary blood donation drives, whole blood donations [WBD] and restricted the donors' movement to the blood transfusion centres all across the world. While sickness and the need for transfusions are very much in place, the gap of demand against blood collection has widened. Additionally, with the monsoon season at hand, and the categorical challenges of a dengue outbreak, the subsequent need for blood components especially the platelet concentrates is going to rise. Some of the criteria laid for deferring a blood donor from his or her WBD need a categorical revision, considering these unprecedented times. We, therefore, critically analyzed the blood donor selection criteria and hereby, suggest an updating regarding the pre-donation haemoglobin, sexually transmitted diseases, lactation, pregnancy and many such subheadings. We also suggest collecting smaller blood volumes in the blood bags for the optimal benefit of the recipients both for now and also as a measure of pandemic preparedness for future use.

Effect of donor, component, and recipient characteristics on hemoglobin increments following red blood cell transfusion

Significant research has focused individually on blood donors, product preparation and storage, and optimal transfusion practice. To better understand the interplay between these factors on measures of red blood cell (RBC) transfusion efficacy, we conducted a linked analysis of blood donor and component data with patients who received single-unit RBC transfusions between 2008 and 2016. Hemoglobin levels before and after RBC transfusions and at 24- and 48-hour intervals after transfusion were analyzed. Generalized estimating equation linear regression models were fit to examine hemoglobin increments after RBC transfusion adjusting for donor and recipient demographic characteristics, collection method, additive solution, gamma irradiation, and storage duration. We linked data on 23 194 transfusion recipients who received one or more single-unit RBC transfusions (n = 38 019 units) to donor demographic and component characteristics. Donor and recipient sex, Rh-D status, collection method, gamma irradiation, recipient age and body mass index, and pretransfusion hemoglobin levels were significant predictors of hemoglobin increments in univariate and multivariable analyses (P < .01). For hemoglobin increments 24 hours after transfusion, the coefficient of determination for the generalized estimating equation models was 0.25, with an estimated correlation between actual and predicted values of 0.5. Collectively, blood donor demographic characteristics, collection and processing methods, and recipient characteristics accounted for significant variation in hemoglobin increments related to RBC transfusion. Multivariable modeling allows the prediction of changes in hemoglobin using donor-, component-, and patient-level characteristics. Accounting for these factors will be critical for future analyses of donor and component factors, including genetic polymorphisms, on posttransfusion increments and other patient outcomes.

The impact of recipient factors on the lower-than-expected hemoglobin increment in transfused outpatients with hematologic diseases

BACKGROUND

Patients with cancer or chronic hematologic disorders frequently receive red blood cell (RBC) transfusions. Based on long-standing assumptions, each RBC unit is thought to increase recipient hemoglobin by 1 g/dL, but smaller increments can occur. A better understanding of recipient factors affecting hemoglobin increments could help providers manage these patients.

METHODS

Data were collected as a part of the observational Red Cells in Outpatients Transfusion Outcomes (RETRO) study of outpatients with hematologic or cancer-related diagnoses. Hemoglobin was measured before transfusion and 30 minutes after transfusion. A classification and regression tree (CART) analysis was performed to identify statistically significant associations with clinical variables. A corresponding prediction equation was developed and validated using linear regression.

RESULTS

A total of 195 participants had both pre- and posttransfusion hemoglobin values for analysis. The median age was 66 years, and patients received one (73%) or two (27%) RBC units during the transfusion episode. The overall median change in hemoglobin was 0.6 g/dL per RBC unit. Both CART analysis and linear regression identified the following significant predictors of hemoglobin increment: number of units received (positive correlation), patient estimated circulating blood volume (negative correlation), pretransfusion hemoglobin (negative correlation), and patient age (negative correlation).

CONCLUSION

In this study of outpatients with hematologic disease, most patients had a hemoglobin increment of less than 1 g/dL/unit. Recipient-specific factors influenced the hemoglobin increment at 30 minutes, and providers should consider circulating blood volume, pretransfusion hemoglobin, and recipient age, when developing patient-specific RBC transfusion plans for this unique cohort.

Changes in the hemoglobin level after one unit of packed red blood cell transfusion in Intensive Care Unit patients

Background:

Blood transfusion is essential in severely ill patients whose hemoglobin (Hb) levels are low, but there are some factors that inhibit optimal increase in Hb. The aim of this study was to evaluate the amount of increase in Hb levels after packed red blood cell (PRBC) transfusions in the Intensive Care Unit (ICU) patients and its related factors.

Materials and Methods:

This cross-sectional study included 124 patients admitted to the ICU, and needed PRBC transfusion. Demographic information, Hb on the 1^st day of admission, blood volume transfusions during the 7 days, and the 7^th day of admission Hb level were extracted from patients’ records.

Results:

The average initial Hb level of patients was reported as 6.17 ± 1.43 g/dl, and after administrating PRBC (4.23 ± 1.87 units during 7 days), the Hb level was 8.09 ± 1.66 g/dl after 7 days (mean difference was 1.91 ± 1.93, t = 11.06, P < 0.001). No significant differences were found between change in Hb level in the terms of age, gender, underlying illness, body mass index, hospitalization history, fever, and duration of hospitalization (P > 0.05). However, the mean increased Hb level in hospitalized patients with internal disorders was the lowest (0.25 g/dl, P = 0.002).

Conclusion:

The results of our study showed that the increased Hb level based on one unit of received PRBC was low, especially in patients with internal. Therefore, based on high frequency of anemia in ICU patients and relative complications, physicians should pay attention to factors affecting Hb levels after PRBC transfusion such as medical history.

Restrictive transfusion threshold is safe in high-risk patients undergoing brain tumor surgery

OBJECTIVE

To assess the safety of a restrictive threshold for the transfusion of red blood cells (RBCs) compared to a liberal threshold in high-risk patients undergoing brain tumor surgery.

PATIENTS AND METHODS

We reviewed patients who were 50 years of age or older with a preoperative American Society of Anesthesiologists physical status class II to V who underwent open craniotomy for tumor resection and were transfused packed RBCs during or after surgery. We retrospectively assigned patients to a restrictive-threshold (a pretransfusion hemoglobin level <8g/dL) or a liberal-threshold group (a pretransfusion hemoglobin level of 8-10/dL). The primary outcome was in-hospital mortality rate. Secondary outcomes were in-hospital complication rates, length of stay, and discharge disposition.

RESULTS

Twenty-five patients were included in the study, of which 17 were assigned to a restrictive-threshold group and 8 patients to a liberal-threshold group. The in-hospital mortality rates were 12% for the restrictive-threshold group (odds ratio [OR] 0.93, 95% confidence interval [CI] 0.07-12.11) and 13% for the liberal-threshold group. The in-hospital complication rates were 52.9% for the restrictive-threshold group (OR 1.13, 95% CI 0.21-6.05) and 50% for the liberal-threshold group. The average number of days in the intensive care unit and hospital were 8.6 and 22.4 days in the restrictive-threshold group and 6 and 15 days in the liberal-threshold group, respectively (P=0.69 and P=0.20). The rates of non-routine discharge were 71% in the restrictive-threshold group (OR 2.40, 95% CI 0.42-13.60) and 50% in the liberal-threshold group.

CONCLUSIONS

A restrictive transfusion threshold did not significantly influence in-hospital mortality or complication rates, length of stay, or discharge disposition in patients at high operative risk.

Blood transfusion indications in neurosurgical patients: A systematic review

Neurosurgical procedures can be complicated by significant blood losses that have the potential to decrease tissue perfusion to critical brain tissue. Red blood cell transfusion is used in a variety of capacities both inside, and outside, of the operating room to prevent untoward neurologic damage. However, evidence-based guidelines concerning thresholds and indications for transfusion in neurosurgery remain limited. Consequently, transfusion practices in neurosurgical patients are highly variable and based on institutional experiences. Recently, a paradigm shift has occurred in neurocritical intensive care units, whereby restrictive transfusion is increasingly favored over liberal transfusion but the ideal strategy remains in clinical equipoise. The authors of this study perform a systematic review of the literature with the objective of capturing the changing landscape of blood transfusion indications in neurosurgical patients.

Haemoglobin responses to transfusion in severe iron deficiency anaemia: potential impact of gastrointestinal disorders

BACKGROUND AND OBJECTIVES

Red blood cell (RBC) transfusion may be justified in iron deficiency anaemia (IDA) when an increase in oxygen delivery is needed, as sometimes occurs in subjects with haemoglobin <8·0 mg/dL, serious comorbidities or at risk of cardiovascular instability. Earlier investigations showed that some patients with severe IDA requiring transfusion had lower than expected post-transfusion haemoglobin levels with poorer clinical outcomes than other patients. After hypothesizing that haemoglobin responses to transfusion were different and that the underlying gastrointestinal (GI) disorders causing IDA could be a confounder explaining this association, these responses were analysed in a prospective cohort of IDA adults referred for outpatient GI investigation.

MATERIALS AND METHODS

Transfused patients with proven IDA, baseline haemoglobin at referral <9·0 g/dL and no extraintestinal bleeding were eligible. To assess a homogeneous population, only GI disorders known to cause occult bleeding were considered. Haemoglobin increments per 100 mL of RBCs were investigated.

RESULTS

In total, 2818 patients were enrolled over 10·5 years. On multivariable regression, diffuse angiodysplasias and GI cancer independently predicted for reduced increments in post-transfusion haemoglobin [adjusted regression coefficients: -0·082 (95% confidence interval, -0·093 to -0·072) and -0·073 (95% confidence interval, -0·081 to -0·066), respectively, P < 0·001 in both]. Haemoglobin responses in the remaining bleeding disorders were adequate and agreed with the principle that one RBC unit increases the haemoglobin an average of 1 g/dL.

CONCLUSION

The potential differential impact of GI disorders on changes in haemoglobin levels after RBC transfusion could be useful for transfusing physicians, especially for diagnostic purposes.

Factors affecting efficacy of packed red blood cell transfusion in neonates

The degree of increase in haematocrit and equilibration time following packed red blood cell (PRBC) transfusion in neonates is not well studied. We evaluated change in haematocrit 15 min, 6 h and 24 h after PRBC transfusion in neonates and factors predicting this change. Among neonates receiving PRBC transfusion, we recorded pre-transfusion haematocrit and a priori identified putative variables affecting change in haematocrit following transfusion. The factors affecting change in haematocrit were analyzed by multiple linear regression analysis. Eighty-one neonates received 119 PRBC transfusions (mean volume 16 ± 4 mL/kg). Haematocrit increased from 26 ± 5 to 41 ± 5% at 15 min after PRBC transfusion (p = 0.001) and remained stable till 6 h (41 ± 5%, p = 0.11). It decreased to 40 ± 5%, at 24 h post transfusion (p < 0.001). On linear regression analysis, baseline haematocrit of the baby, donor blood haematocrit and volume of PRBC transfusion were independent determinants of increase in haematocrit.

CONCLUSION

After 16 mL/kg PRBC transfusion in neonates, haematocrit increased by 15% at 15 min post transfusion. The equilibration in haematocrit values was achieved by 15 min after transfusion. Baseline haematocrit of neonate, donor blood haematocrit and transfusion volume independently determine the rise in haematocrit. What is Known: • Rise in haematocrit following PRBC transfusion in neonates has been studied in a small number of stable infants. • Determinants of efficacy of PRBC transfusion have not been well studied in newborns. What is New: • Each milliliter/kilogramme of PRBC transfusion increases the neonate's haematocrit by approximately 1%. • Baseline haematocrit, donor blood haematocrit and transfusion volume per kilogramme body weight independently determine the rise in haematocrit.

Red Blood Cell Transfusions and Iron Therapy for Patients Presenting with Acute Upper Gastrointestinal Bleeding: A Survey of Canadian Gastroenterologists and Hepatologists

Introduction. There is limited data evaluating physician transfusion practices in patients with acute upper gastrointestinal bleeding (UGIB). Methods. A web-based survey was sent to 500 gastroenterologists and hepatologists across Canada. The survey included clinical vignettes where physicians were asked to choose transfusion thresholds. Results. The response rate was 41% (N = 203). The reported hemoglobin (Hgb) transfusion trigger differed by up to 50 g/L. Transfusions were more liberal in hemodynamically unstable patients compared to stable patients (mean Hgb of 86.7 g/L versus 71.0 g/L; p < 0.001). Many clinicians (24%) reported transfusing a hemodynamically unstable patient at a Hgb threshold of 100 g/L and the majority (57%) are transfusing two units of RBCs as initial management. Patients with coronary artery disease (mean Hgb of 84.0 g/L versus 71.0 g/L; p < 0.01) or cirrhosis (mean Hgb of 74.4 g/L versus 71.0 g/L; p < 0.01) were transfused more liberally than healthy patients. Fewer than 15% would prescribe iron to patients with UGIB who are anemic upon discharge. Conclusions. The transfusion practices of gastroenterologists in the management of UGIB vary widely and more high-quality evidence is needed to help assess the efficacy and safety of selected transfusion thresholds in varying patients presenting with UGIB.

Predictors for 1-year mortality following hip fracture: a retrospective review of 465 consecutive patients

INTRODUCTION

In Europe, trauma admissions and in particular hip fractures are on the rise. In recent years, health care systems have placed particular emphasis, including financial incentives, on delivering patients quickly and safely to surgery. At our unit, we have observed that hip fracture patients appear to be at significant risk of mortality even up to a year following injury. This study reviews a consecutive population of hip fracture patients to identify predictors of excess risk.

MATERIALS AND METHODS

Four hundred and sixty-five consecutive patients were treated over a 2-year period at our district general hospital with no ward-based orthogeriatricians. Follow-up was for 1 year following hip fracture admission. Statistical analysis of variables and their influence on 1-year mortality were performed by calculating odd's ratio (OR) using a logistic regression model and a p value <0.05 was considered statistically significant.

RESULTS

Four patients were lost to follow-up, 18 patients (4.1 %) were managed conservatively, 16 were too unwell for surgery and their mortality rate at 1 year was 50 %. Following hip fracture, we found an overall 1-year mortality rate of 15.1 %. Patients with a time to surgery ≥36 h were at significantly increased risk of mortality even up to 1 year. We did not identify a further reduction in mortality in those operated on within 24 h. Raised ORs (p > 0.05) were found with increasing comorbidity, surgery type, independence on discharge, alcohol ingestion, history of smoking, readmission and several biochemical markers.

CONCLUSION

Minimising mortality risk, even over the longer term, should begin on admission with prompt optimisation of any acute medical or biochemical abnormalities, followed by early surgery and intensive rehabilitation to maintain patients' functional independence.

Impact of erythropoietin on intensive care unit patients

Anemia is common in intensive care unit (ICU) patients. Red blood cell (RBC) transfusions are mainstays of their treatment and can be life-saving. Allogeneic blood components inherently bear risks of infection and immune reactions. Although these risks are rare in developed countries, recombinant human erythropoietin (rhEpo) and other erythropoiesis-stimulating agents (ESAs) have been considered alternative anti-anemia treatment options. As summarized herein, however, most of the clinical studies suggest that ESAs are not usually advisable in ICU patients unless approved indications exist (e.g., renal disease). First, ESAs act in a delayed way, inducing an increase in reticulocytes only after a lag of 3-4 days. Second, many critically ill patients present with ESA resistance as inflammatory mediators impair erythropoietic cell proliferation and iron availability. Third, the ESA doses used for treatment of ICU patients are very high. Fourth, ESAs are not legally approved for general use in ICU patients. Solely in distinct cases, such as Jehovah's Witnesses who refuse allogeneic blood transfusions due to religious beliefs, ESAs may be considered an exceptional therapy.

Predicting change of hemoglobin after transfusion in hemodynamically stable anemic patients in emergency department

BACKGROUND

To investigate factors associated with change of post-transfusion hemoglobin level, and to derive an equation that predicts post-transfusion changes in hemoglobin levels in hemodynamically stable anemic patients who visited emergency department.

METHODS

A retrospective medical record review of patients who were hemodynamically stable and transfused with packed red blood cells was undertaken. Patients were randomly divided into two groups. One group (derivation group, 70% of total patients) was analyzed for factors associated with changes in post-transfusion hemoglobin levels, and linear regression analysis was performed to derive a prediction equation. The derived prediction equation was then externally validated with the other group (validation group, 30% of total patients).

RESULTS

A total of 196 patients were enrolled. The 137 patients (70% of total patients) in the derivation group were analyzed for factors associated with changes in post-transfusion hemoglobin. Of those, body surface area and initial hemoglobin level were significantly correlated with changes in post-transfusion hemoglobin levels (p < 0.05). From these variables, linear regression analysis resulted in a prediction equation. The derived equation was validated externally with the 59 patients (30% of total patients) in the validation group and found to have an excellent correlation (r = 0.73, intraclass correlation = 0.84, p < 0.05).

CONCLUSIONS

Post-transfusion hemoglobin level in hemodynamically stable adult patients was associated with initial hemoglobin levels and body surface area. These factors must be considered when transfusing hemodynamically stable adult patients with anemia.

Neurobiology confirms psychopathology. On the antagonism of psychosis and obsessive-compulsive syndromes

BACKGROUND

Psychopathological concepts of the 19th and early 20th century postulated an antagonism between psychotic and obsessive-compulsive disorders, assuming obsessions and compulsions to have protective effects on psychotic disintegration. Although both disorders have been subject to intense multimodal research, their pathogeneses are yet to be fully understood.

METHODS

Here, we discuss recent neurobiological findings pointing towards opposite directions which are strongly reminiscent of the historical psychopathological antagonism.

RESULTS

Obsessive-compulsive syndromes (OCS) are efficiently treated with serotonergic substances, while on the other hand modern antipsychotic drugs exert antiserotonergic effects. Especially these atypical antipsychotic substances, however, were found to involve the risk of inducing second-onset OCS. Dopamine antagonists are potent antipsychotic substances, whereas the partial dopamine agonist aripiprazole has been associated with an antiobsessive potency. Within the glutamatergic system, reduced NMDA-dependent glutamatergic neurotransmission is discussed to be one major pathomechanism of psychotic disorders, whilst NMDA antagonists have proven to be effective in improving treatment-resistant OCS. While neurogenetic findings seem to separate the populations in heterogeneous samples, detailed neuroimaging studies suggest that both disorders affect similar neurocircuits in different manners.

CONCLUSIONS

With regard to these findings, future research on schizo-obsessive syndromes will have to be multimodal, integrating psychopathology, neuropsychology, functional imaging, neurogenetics and psychopharmacology. Prospective trials involving these methods might be able to elucidate the dysbalances of neurotransmission and to locate the neuroanatomical and neuropsychological correlates. In particular, this might contribute to defining schizophrenic patients at risk for developing second-onset OCS and to evaluating new treatment strategies in patients suffering from both psychosis and OCS.