Long-term use of proton pump inhibitors and vitamin B12 status in elderly individuals

Background  Some studies have shown that short-term use of proton pump inhibitors decreases the absorption of vitamin B12, but the results of studies into long-term proton pump inhibitor use and vitamin B12 deficiency are inconsistent.
Aim  To investigate whether long-term proton pump inhibitor use is associated with an abnormal vitamin B12 status in elderly individuals.
Methods  One hundred and twenty-five long-term (>3, years) proton pump inhibitor users aged 65, years and above were recruited from general practices. Their 125 partners (who did not use proton pump inhibitors) served as the reference group. Vitamin B12 status was determined by serum levels of vitamin B12 and homocysteine, and mean corpuscular volume.
Results  No differences in mean vitamin B12 levels were observed between the long-term proton pump inhibitor users and their partners [345 (s.d. 126), p m vs. 339 (s.d. 133), p m , P, = , 0.73], even after adjustment for age, gender, Helicobacter pylori status and C-reactive protein levels ( P, = , 0.87). Four proton pump inhibitor users and three partners had vitamin B12 levels <150, p m (3% vs. 2%, P, = , 1.00). No differences between the groups were observed in homocysteine levels and mean corpuscular volume.
Conclusions  No association between long-term proton pump inhibitor use and vitamin B12 status was observed. Regular testing for low vitamin B12 levels in elderly patients on long-term treatment with proton pump inhibitors is therefore not recommended.     

Management of adrenal insufficiency in different clinical settings

Adrenal insufficiency is a rare disease, but its prevalence is increasing. The most frequent cause of primary adrenal insufficiency in western countries is autoimmune adrenalitis, whereas secondary adrenal insufficiency is most often caused by pituitary tumours and their treatment (e.g., surgery). Chronic glucocorticoid replacement consists of hydrocortisone 15-25 mg/day in divided doses and dose monitoring is largely based on clinical judgement. Fludrocortisone 0.05-0.2 mg/day is given for substitution in mineralocorticoid deficiency aiming at normotension, normokalaemia and a plasma renin activity in the upper normal range. It has recently been shown that, despite adequate glucocorticoid and mineralocorticoid replacement well being in patients with adrenal insufficiency is still impaired. Several studies have demonstrated that dehydroepiandosterone 25-50 mg/day p.o. may improve mood, fatigue, well-being and, in women, also sexuality, suggesting that dehydroepiandosterone should become part of the standard treatment regime. However, large Phase III trials of dehydroepiandosterone for adrenal insufficiency are still lacking and it has not yet been approved for the treatment of this disease. Patients with adrenal insufficiency are at risk of adrenal crisis, usually precipitated by major stress, such as severe infection or surgery. Early dose adjustments are required to cover the increased glucocorticoid demand in stress. Careful and repeated education of patients and their partners is the best strategy to avoid this life-threatening emergency. Some recent studies suggest that during sepsis some patients with intact adrenal function may develop transient relative adrenal insufficiency and benefit from administration of hydrocortisone plus fludrocortisone. However, the pathophysiology and diagnosis criteria of relative adrenal insufficiency and its treatment remain unsettled issues.     

Use of the deoxyuridine suppression test to evaluate vitamin B12 and folate status

The deoxyuridine suppression test (DUST), performed on bone marrow cells, or peripheral blood lymphocytes, provides a rapid, dynamic assessment of vitamin B12 and folate status. The principles of this test are described and the use of the DUST in haematological practice at Wellington Hospital is reviewed. The advantages of the test are the speed of obtaining results, and an accurate assessment of the patient's condition when other haematological tests may be misleading.     

Management of adrenal insufficiency in different clinical settings

Adrenal insufficiency is a rare disease, but its prevalence is increasing. The most frequent cause of primary adrenal insufficiency in western countries is autoimmune adrenalitis, whereas secondary adrenal insufficiency is most often caused by pituitary tumours and their treatment (e.g., surgery). Chronic glucocorticoid replacement consists of hydrocortisone 15 – 25 mg/day in divided doses and dose monitoring is largely based on clinical judgement. Fludrocortisone 0.05 – 0.2 mg/day is given for substitution in mineralocorticoid deficiency aiming at normotension, normokalaemia and a plasma renin activity in the upper normal range. It has recently been shown that, despite adequate glucocorticoid and mineralocorticoid replacement well being in patients with adrenal insufficiency is still impaired. Several studies have demonstrated that dehydroepiandosterone 25 – 50 mg/day p.o. may improve mood, fatigue, well-being and, in women, also sexuality, suggesting that dehydroepiandosterone should become part of the standard treatment regime. However, large Phase III trials of dehydroepiandosterone for adrenal insufficiency are still lacking and it has not yet been approved for the treatment of this disease. Patients with adrenal insufficiency are at risk of adrenal crisis, usually precipitated by major stress, such as severe infection or surgery. Early dose adjustments are required to cover the increased glucocorticoid demand in stress. Careful and repeated education of patients and their partners is the best strategy to avoid this life-threatening emergency. Some recent studies suggest that during sepsis some patients with intact adrenal function may develop transient relative adrenal insufficiency and benefit from administration of hydrocortisone plus fludrocortisone. However, the pathophysiology and diagnosis criteria of relative adrenal insufficiency and its treatment remain unsettled issues.     

维生素B12治疗周围神经病变的临床疗效比较

目的 比较目前临床应用相对较多的两种维生素B12制剂对周围神经病变临床症状的疗效.方法 选取天津市第一医院临床收纳的满足试验条件的神经卡压性周围神经病变患者,随机分为甲钴胺组(41例),腺苷钴胺组(39例)和针灸组(41例),甲钴胺组患者静脉滴注弥可保,每次0.5 mg,1次/d;腺苷钴胺组患者肌肉注射腺苷钴胺,每次0.5 mg,1次/d;针灸组选用针灸理疗、按摩等常规治疗.3组患者均治疗两周.观测治疗后患者的主观症状、各项体征,并严密观察、记录试验期间发生的不良反应事件.结果 3组治疗患者均未见不良反应,甲钴胺组在主观症状、客观体征方面改善均优于腺苷钴胺组及针灸组.结论 甲钴胺作为最新一代的维生素B12临床应用疗效、安全性方面均优于以往维生素B12,且西医治疗周围神经病变较单纯针灸治疗有明显疗效优势.