Longo Stacy L, Ryan Jessica M, Sheehan Kelsey B, Reid Debra J, Conley Michael P, Bouwmeester Carla J
Clinical Pharmacist. The Dimock Center, Roxbury, MA (United States).
Clinical Pharmacist. Harbor Health Services Community Health Centers, Boston, MA (United States).
Pharm Pract (Granada). 2019 Jul-Sep;17(3):1499. doi: 10.18549/PharmPract.2019.3.1499. Epub 2019 Sep 13.
Previous studies linked metformin use to vitamin B12 deficiency and demonstrated that the prevalence of vitamin B12 monitoring remains low.
This study aimed to assess the occurrence of monitoring vitamin B12 levels in a diverse population.
This was a retrospective chart review of adult patients with type 2 diabetes on metformin doses ≥ 1000 mg for ≥ 6 months at five Federally Qualified Health Centers (FQHC) and one Program of All-Inclusive Care for the Elderly (PACE). Charts were reviewed for occurrence of monitoring vitamin B12 levels in the past 5 years. Data collected included patient demographics, laboratory data, other potential vitamin B12 level lowering agents, active prescription for vitamin B12 supplementation, concomitant diabetes medications and metformin total daily dose.
Of the 322 patients included, 25% had a vitamin B12 level measured in the previous five years. Among the patients with a vitamin B12 level, 87.7% were within the normal range (>350 pg/mL), 11.1% were low (200-300 pg/mL), and only one patient (1.2%) was deficient (<200 pg/mL). These patients were older (69.2 vs. 56.4, p<0.001); more likely to be white (56.8% vs. 37.8%, p=0.04); and more likely to use proton pump inhibitors (34.6% vs. 20.7%, p=0.02) and vitamin B12 supplementation (27.2% vs. 4.6%, p<0.001). Vitamin B12 monitoring differed between the FQHC (15.2%) and PACE (97.4%) sites (p<0.001). Each greater year of age was associated with a 5% increased odds of vitamin B12 monitoring (a OR: 1.05; 95% CI: 1.02-1.08).
The majority of patients seen at the FQHC sites did not have vitamin B12 levels monitored, however, most of the patients who were monitored had normal vitamin B12 levels, which may warrant extending the monitoring time. This finding may also support monitoring patients who have additional risk factors for vitamin B12 deficiency such as concurrent medication use with other vitamin B12 lowering agents or clinical symptoms of deficiency such as peripheral neuropathy. Future studies are needed to determine appropriate frequency of monitoring.
既往研究将二甲双胍的使用与维生素B12缺乏联系起来，并表明维生素B12监测的普及率仍然很低。
本研究旨在评估不同人群中维生素B12水平监测的情况。
这是一项回顾性病历审查，研究对象为在五家联邦合格医疗中心（FQHC）和一个老年人全包式护理项目（PACE）中服用二甲双胍剂量≥1000mg且持续≥6个月的成年2型糖尿病患者。审查病历以了解过去5年中维生素B12水平监测的情况。收集的数据包括患者人口统计学资料、实验室数据、其他可能降低维生素B12水平的药物、维生素B12补充剂的有效处方、同时使用的糖尿病药物以及二甲双胍的每日总剂量。
在纳入的322例患者中，25%在过去五年中检测过维生素B12水平。在检测过维生素B12水平的患者中，87.7%处于正常范围（>350 pg/mL），11.1%偏低（200 - 300 pg/mL），只有1例患者（1.2%）缺乏（<200 pg/mL）。这些患者年龄较大（69.2岁对56.4岁，p<0.001）；更可能是白人（56.8%对37.8%，p = 0.04）；更可能使用质子泵抑制剂（34.6%对20.7%，p = 0.02）和维生素B12补充剂（27.2%对4.6%，p<0.001）。FQHC（15.2%）和PACE（97.4%）站点之间的维生素B12监测情况存在差异（p<0.001）。年龄每增加一岁，维生素B12监测的几率增加5%（调整后比值比：1.05；95%置信区间：1.02 - 1.08）。
在FQHC站点就诊的大多数患者未进行维生素B12水平监测，然而，大多数接受监测的患者维生素B12水平正常，这可能需要延长监测时间。这一发现也可能支持对有维生素B12缺乏其他危险因素的患者进行监测，如同时使用其他降低维生素B12水平的药物或有缺乏的临床症状（如周围神经病变）。未来需要研究确定合适的监测频率。
