How Many Patients Are in Need of Vitamin B12 Injections?

Study Overview
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Brief Summary
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The clinical consequences of vitamin B12 deficiency include megaloblastic anemia and neurological disorders. Therefore, a proper and timely diagnosis and treatment is important. The use of sensitive biochemical markers such as methylmalonic acid for the diagnosis of vitamin B12 deficiency have increased since the 1980s. Consequently, the number of individuals treated with vitamin B12 has increased significantly. The objective of this project is to study the actual need for vitamin B12 injections in the group of individuals who have already started treatment. In order to investigate this, the investigators stop vitamin B12 treatment in this group, and look for signs of vitamin B12 deficiency by monitoring changes in biochemical and hematological markers. Furthermore, they will test if the individuals are able to absorb a physiological dose of vitamin B12 using a recently developed absorption test (CobaSorb). If a physiological dose can be absorbed, the vitamin B12 injections can be replaced with tablets. In the end, the investigators hope to be able to divide the patients into three groups: need life long injections with vitamin B12, only need supplementations with a small dose of oral vitamin B12, and no need for further vitamin B12 treatment. The perspective is that the new information from this study might be used for a future strategy for vitamin B12 treatment.

Detailed Description
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The clinical consequences of vitamin B12 deficiency include megaloblastic anemia and neurological disorders. Therefore, a proper and timely diagnosis and treatment is important. The use of sensitive biochemical markers such as methylmalonic acid for the diagnosis of vitamin B12 deficiency have increased since the 1980s. Consequently, the number of individuals treated with vitamin B12 has increased significantly. The objective of this project is to study the actual need for vitamin B12 injections in the group of individuals who have already started treatment. In order to investigate this, the investigators stop vitamin B12 treatment in this group, and look for signs of vitamin B12 deficiency by monitoring changes in biochemical and hematological markers. Furthermore, they will test if the individuals are able to absorb a physiological dose of vitamin B12 using a recently developed absorption test (CobaSorb). If a physiological dose can be absorbed, the vitamin B12 injections can be replaced with tablets. In the end, the investigators hope to be able to divide the patients into three groups: need life long injections with vitamin B12, only need supplementations with a small dose of oral vitamin B12, and no need for further vitamin B12 treatment. The perspective is that the new information from this study might be used for a future strategy for vitamin B12 treatment.

Official Title
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How Many Patients Are in Need of Vitamin B12 Injections?

Conditions
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Vitamin B12 Deficiency

Intervention / Treatment
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* Drug: vitamin B12


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Above 17 years old Have received vitamin B12 treatment for at least one year Capable of reading and understanding Danish Exclusion Criteria: Pregnant or nursing women Not capable of giving informed consent Acute infection during the 3-day examination of vitamin B12 absorption

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: vitamin B12|9 µg vitamin B12 three times daily for two days (CobaSorb)|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in plasma cobalamins |  | Every month | 
| Change in plasma methylmalonic acid |  | Every month | 
| Change in plasma holotranscobalamin |  | Every month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vitamin B12 deficiency, Vitamin B12 absorption, Holotranscobalamin