Vitamin and mineral deficiencies after LSG: A huge challenge
Despite the many benefits of bariatric surgery, one of the long-term complications remains underreported and in some cases more worryingly, untreated. Vitamin and mineral deficiencies are one of most common complication after bariatric surgery. These shortages in essential micronutrients can lead to anaemia, hair loss and osteoporosis, as well as profound consequences reducing a patient’s quality of life, and in more severe cases, life expectancy. Although guidelines exist on nutritional deficiencies1, there is still a lack of awareness and education in both patients and doctors. In fact, research has shown that 57% of patients are micronutrient deficient within the first year of surgery.2
Bariatric News spoke with Dr. Edo Aarts, Surgical Resident and Head Bariatric Research, Rijnstate Hospital and Vitalys Clinic in Arnhem, the Netherlands, about vitamin and mineral deficiencies after bariatric surgery and specifically laparoscopic sleeve gastrectomy, and why all healthcare professional involved in bariatric surgery need to be educated about the importance of pre- and post-surgical evaluation of nutritional deficiencies.
Most post-surgical after care is done by surgeons, but post-nutritional care has only come to the forefront in the last ten years. Previously, patients were unlikely to receive post-operative care nutritional deficiency advice, despite the fact that nutritional problems are common and can continue for the duration of a patients’ lifetime after surgery. According to Dr. Aarts, this is why it is very important patients receive lifelong nutritional deficiency assessments.
There are several known nutritional deficiencies following bariatric surgery, but the type of deficiency depends on whether a patient has undergone restrictive surgery, such as the gastric sleeve, or restrictive and malabsorptive procedures such as the biliopancreatic diversion and gastric bypass procedures.
It has long been thought that deficiencies mostly occurred in procedures with a malabsorptive component, like the rouxen-y gastric bypass or the biliopancreatic diversion, only. The risk for developing deficiencies after non-bypass bariatric surgery like the sleeve gastrectomy was considered low and patients were often not even tested for deficiencies.3 However, research shows that in the restrictive types of surgery deficiencies occur almost as much.3,4
“We know that the malabsorptive component of the gastric bypass leads to deficiencies in micronutrients such as iron and vitamin B12. In addition, after a gastric bypass the ‘carrier’ intrinsic factor – which is need for the absorption of vitamin B12 – is no longer released, so there is only passive absorption,” said Dr. Aarts. “After a sleeve gastrectomy, there is usually less intake so a patient cannot eat sufficient amounts of food to obtain the adequate levels of nutrients and minerals, and patients do not have sufficient amounts of gastric acid in the stomach to convert the iron in the food into their digestive system. So even though a patient consumes ample amounts of iron it will not be absorbed and transferred from iron 3+ into iron 2+ sufficiently.”
Research by Capoccia et al. showed that following laparoscopic sleeve gastrectomy a significant proportion of patients developed vitamin B12 and folate deficiency.4 Even though Capoccia did not report any iron deficiency in this patient group, Dr. Aarts and colleagues did report an iron deficiency in 43% of the patients who had received the same procedure. In addition, anaemia was seen in 26% of patients and significantly low B12, folate, iron and vitamin D levels in this group of sleeve gastrectomy patients.3
“There is no doubt that in practice the levels of nutritional deficiencies after sleeve gastrectomy are higher than those reported in the literature. There is an urgent need to increase awareness of this problem by reporting the actual levels of nutritional deficiencies in the published literature,” said Dr. Aarts. “In our series, 28% of patients were anaemic, but the literature states only a few percent of anaemia cases per year. This is incorrect, nutritional deficiency rates after sleeve gastrectomy are grossly underreported. The sleeve gastrectomy is the number one operation in the world at the moment and the most common complications at the moment are due to deficiencies as a result of the procedure. Some patients who have undergone a sleeve gastrectomy are told they do not need supplementation, this is 100% untrue.”
“There are a lot of things we do not know about nutritional deficiencies after bariatric surgery, and especially the sleeve gastrectomy, so more research needs to be carried out before we can say that the guidelines are sufficient.”
Overall, he said there are two primary causes of nutritional deficiency following bariatric surgery: 1) a lack of food intake and 2) changes to the gastrointestinal tract due to the surgery. The latter results in the difficulty of the absorption of food nutrients into the bloodstream of the patient’s body.
However, following weight loss surgery many patients suffer from nutritional deficiencies, while others do not have this problem. According to Dr. Aarts, there are a number of factors explaining this phenomenon, but in general it is not due to different alterations of the gastro intestinal (GI) tract that restricts the patient’s ability to absorb vitamins and minerals, but rather the patient’s lifestyles and their eating habits after surgery.
For example, those patients who have a diverse diet (fruit, vegetables, cereal, bread etc.) following surgery do have better nutritional intake compared to those patients who have a limited and unbalanced diet. Following surgery, some morbidly obese patients will lose weight, because they are restricted in the amount of food they can eat, however they are not consuming the most healthy types and/or the best variety of foods. As a result, they are not providing their bodies with the (adequate amounts of) essential nutrients required to stay healthy – resulting in the deficiencies seen in many of our patients.
“If you combine a poor diet with a reduction in the malabsorptive capabilities of the GI tract, following surgery, this compounds a patient’s nutritional deficiencies. This combination is why many patients present with nutritional deficiencies within the first year of surgery,” he explained.
He added that there is also a difference between male and female patients – premenopausal female patients do not have the same iron reserves of their male counterparts because many of the female patients are still fertile and lose iron due to their menstrual cycle.
“This is the same as in the general population, but of course this lack of iron is exacerbated after bariatric surgery,” he added.
In his experience, the most common deficiencies are iron, vitamin B12, folic acid and vitamin D. Vitamin D is particularly important for bone density, but this deficiency goes unnoticed by patients as it takes years before it becomes a real problem. For example, osteoporosis is now a significant problem among those bariatric patients who have undergone surgery 15-20 years ago, Dr. Aarts explained.
By performing pre-operative nutritional assessments at his centre, Dr. Aarts and colleagues have reported that one in four obese patients have nutritional deficiencies and are malnourished due to a lack of diversity in their diet. Furthermore, because these patients rarely leave their house, many present with vitamin D deficiency.
“We must keep in mind that it is much easier to provide multivitamin supplements before surgery, because the GI tract has not been altered, for this reason it is imperative that patients have pre-operative testing to identify which nutritional deficiencies they have, so they can be treated pre-operatively.”
He added that it is much more difficult to supplement patients after surgery. Therefore, by identifying their nutritional deficiencies earlier, patients are given an opportunity to reduce their deficiencies prior to surgery when their GI tract can absorb multivitamin supplements well yet.
“We know that testing for nutritional deficiencies prior to surgery and prescribing supplements before surgery give patients the opportunity to build up the vitamin and mineral levels in the body, which results in a reduction in post-operative complaints such as fatigue. The evidence shows that patients are far less likely to suffer from short- and long-term nutritional deficiencies when provided with adequate pre-operative nutritional supplements.”
For over ten years, Dr. Aarts has been researching vitamin and nutritional deficiencies in bariatric surgical patients. He soon noticed that a large amount of time and expense was spent on nutritional supplements for patients after bariatric surgery. As a result, he has started to develop different multivitamins for gastric bypass patients. In 2008, he started working with the Dutch company, FitForMe (Rotterdam, The Netherlands).