Thiamin (vitamin B1) plays an important role in energy metabolism and cell function. Thiamin deficiency is common both before and after bariatric surgery and, if left untreated, can have serious consequences. Here is what you need to know.
Key takeaways
- Thiamin is not stored in large quantities; its half-life is only a few weeks, so daily intake is imperative.
- Pre-operative deficiency rates of 15.5–29% have been reported.
- After surgery, deficiency can develop in as few as 20 days without supplementation.
- Untreated deficiency can lead to Wernicke encephalopathy, wet beriberi and death.
Pre-operative deficiency
Thiamin plays an important role in energy metabolism (through the metabolism of glucose) and cell function; it is essential for tissues and organs to function properly. Thiamin deficiency can lead to cardiac and neurological abnormalities.1 Thiamin is not stored in large quantities in the body, and its half-life is only a few weeks, so dietary and supplemental intake is imperative.
Food sources of thiamin include wholegrains, meat and seafood, and fortified foods such as bread and cereals; some of these foods are beyond the budget of many patients.
In a study by Flancbaum et al, the pre-operative thiamin deficiency rate was 29%, with Hispanic and African American patients having a higher prevalence (47.2% and 31%).2 Another study of over 300 patients in the pre-operative phase found low thiamin levels in forty-seven (15.5%) participants, most of them female.3
Post-operative deficiency
Thiamin deficiency can lead to Wernicke encephalopathy, wet beriberi and ultimately death if left untreated. Wernicke encephalopathy is diagnosed by a change in mental status, eye movement abnormalities and ataxia. Early symptoms of thiamin deficiency are non-specific and can include fatigue, lethargy, uneasiness and headaches.4 If untreated, symptoms can progress to congestive heart failure or wet beriberi, peripheral neuropathy, dysphagia, depression or Korsakoff syndrome.4 Kröll et al. developed an overview of Wernicke encephalopathy after sleeve gastrectomy:4
| Progression of Wernicke encephalopathy after sleeve gastrectomy | |
|---|---|
| Risk factors | Recurrent vomiting; non-compliance and inadequate vitamin supplementation; pre-operative vitamin B deficiencies; surgical complications (stenosis); parenteral feeding, caloric carbohydrate diet; co-morbidities: alcohol consumption, type 2 diabetes, hepatic stenosis, non-alcoholic fatty liver disease, delayed gastric emptying |
| Timing of neurological symptoms | Early: within 2–6 weeks (stores can be depleted). Late: within 7 months with variability, usually within 3–5 months |
| Clinical manifestations | Wernicke encephalopathy (ocular dysfunction, gait ataxia, encephalopathy) – the classic triad is often not seen; altered mental status; Korsakoff syndrome (amnestic-confabulatory syndrome); peripheral neuropathy and polyradiculopathy; non-specific symptoms: fatigue, lethargy, restlessness; atypical symptoms: vestibular dysfunction without hearing loss, dysphagia, depression |
| Diagnostic tools | Clinical diagnosis; laboratory examination may not be specific, serum thiamin levels may be reduced; MRI may show increased T2 signals in periventricular regions |
| Differential diagnosis | Other nutrient deficiencies: vitamin B12, copper, folate, niacin, vitamin E |
| Treatment | 500 mg thiamin IV three times a day for 2 days, followed by 500 mg/day IV or IM for 5 days with magnesium and other B vitamins, followed by long-term oral supplementation of 50 or 100 mg/day |
| Outcome | Complete recovery is rare |
Adapted from Kröll D, Laimer M, Borbély Y, Laederach K, Candinas D, Nett P. (2015). Wernicke encephalopathy: a future problem even after sleeve gastrectomy? A systematic literature review. Obesity Surgery. 26. 10.1007/s11695-015-1927-9.
Bariatric surgery can increase the risk of thiamin deficiency due to nausea and vomiting, rapid weight loss and excessive alcohol intake.4 Since thiamin is a water-soluble vitamin, daily intake is needed to maintain normal serum levels: Sechi et al. found that a lack of thiamin intake can lead to deficiency in as few as 20 days without appropriate supplementation.5 Angelou et al. found that Wernicke encephalopathy occurred as early as 2 weeks and as late as 60 weeks after sleeve gastrectomy.6
Post-operative thiamin deficiency was found in up to 25% of patients up to 2 years post-op and ranged from 0–30.8% by the 5-year mark, regardless of supplementation.7 A Johns Hopkins University study of 105 patients after sleeve gastrectomy found that patients with a higher BMI and/or of a minority ethnicity had a higher risk of thiamin deficiency: 20% at 3 months, 17% at 6 months and 20% at 12 months after surgery, even while taking the recommended 3 mg of thiamin daily.7
Contact your bariatric team immediately if you experience persistent vomiting or symptoms such as confusion, problems with balance or eye movement.
Sources
- Kaidar-Person O, Person B, Szomstein S, Rosenthal RJ. Nutritional deficiencies in morbidly obese patients: a new form of malnutrition? Part B: minerals. Obes Surg. 2008;18(8):1028–1034. doi:10.1007/s11695-007-9350-5
- Flancbaum L, Belsley S, Drake V, et al. Preoperative nutritional status of patients undergoing Roux-en-Y gastric bypass for morbid obesity. J Gastrointest Surg. 2006;10:1033–1037. https://doi.org/10.1016/j.gassur.2006.03.004
- de Lima KV, Costa MJ, Gonçalves Mda C, Sousa BS. Micronutrient deficiencies in the pre-bariatric surgery. Arq Bras Cir Dig. 2013;26 Suppl 1:63-66. doi:10.1590/s0102-67202013000600014
- Kröll D, Laimer M, Borbély YM, et al. Wernicke encephalopathy: a future problem even after sleeve gastrectomy? A systematic literature review. Obes Surg. 2016;26:205–212. https://doi.org/10.1007/s11695-015-1927-9
- Sechi G, Serra A. Wernicke's encephalopathy: new clinical settings and recent advances in diagnosis and management. Lancet Neurol. 2007;6(5):442–455. doi:10.1016/S1474-4422(07)70104-7
- Athanasiou A, Angelou A, Diamantis T. Wernicke's encephalopathy after sleeve gastrectomy. Where do we stand today? A reappraisal. Surg Obes Relat Dis. 2014;10(3):563. doi:10.1016/j.soard.2014.01.028
- Tang L, Alsulaim HA, Canner JK, Prokopowicz GP, Steele KE. Prevalence and predictors of postoperative thiamin deficiency after vertical sleeve gastrectomy. Surg Obes Relat Dis. 2018;14(7):943–950. doi:10.1016/j.soard.2018.03.024
This article is for general information only and does not replace personal medical advice. Always discuss your situation, blood test results and supplementation with your bariatric team or healthcare provider.