With the improvement of the material living standard and the change of lifestyle, the incidence of metabolic diseases, especially diabetes, is rapidly increasing. According to a survey conducted by the Chinese Medical Association Diabetes Branch in 2007-2008, the prevalence of diabetes among adults in China reached 9.7%, with about 92.4 million people; the number of people with pre-diabetes has reached 148 million. International experts expect that by 2030, the number of people with diabetes will double on top of the existing number, and by then China will be the world’s largest diabetic population.
Diabetes is divided into type 1 and type 2, the majority of which are type 2 diabetes, accounting for about 90% of the total number of diabetics. type 2 diabetes is a metabolic disorder syndrome with insulin resistance and varying degrees of islet hypofunction.
Diabetes is nicknamed “the silent killer” abroad. The great danger of diabetes is the serious complications that can cause death and disability, and is the primary factor of new blindness, end-stage renal disease and non-traumatic amputation in adults; macrovascular disease in diabetes is also a common cause of myocardial infarction and cerebrovascular disease. Statistics show that patients who have had diabetes for more than 5 years begin to develop complications gradually; 70% of diabetics will die from complications. The cruel reality brings great disasters to diabetic patients and their families, causing heavy psychological and economic burdens. Therefore, diabetes has now become the third major non-communicable disease after cardiovascular diseases and tumors, and is a worldwide public health problem that seriously threatens human health!
At present, the traditional treatment of diabetes remains the “five horsemen” of health education, diet, exercise, self-monitoring and drug therapy. However, due to the large population of people with diabetes and the differences in compliance of patients at different levels, some patients have difficulty in maintaining long-term stability of blood glucose with traditional medical treatments, and cannot avoid the emergence and further aggravation of various complications of diabetes. In addition, strict dietary control, regular injections and medication and repeated blood glucose fluctuations cause continuous mental stress to patients and affect their quality of life. Patients are in urgent need of a treatment that provides good control of diabetes and its complications.
Surgical treatment of diabetes is still a novelty in our country, but it has been available in the United States for more than 30 years. Currently more than 200,000 diabetic patients are treated with surgery each year in the United States. Since 2011, the International Diabetes Federation (IDF) has formally promoted surgery worldwide, and has pointed out that surgery is not the last straw for diabetic patients, but should be performed early, and the earlier the surgery, the better.
Laparoscopic gastric bypass surgery
This is the most mainstream and commonly used surgical method for the treatment of type 2 diabetes in the international arena. Only four to five small holes of 0.5 to 1.2 cm in diameter are made in the patient’s abdomen, and a special mechanical cutter is used to sever the large part of the stomach and form a small gastric sac of about 50 ml proximally. The proximal end is anastomosed with the jejunum at 70-150 cm from the gastro-jejunal anastomosis. This procedure allows food to flow directly from the newly formed exit of the small gastric sac into the lower jejunum, bypassing the greater part of the stomach, duodenum, and upper jejunum.
Exploring the mechanism of action of surgery for type 2 diabetes
Weight reduction is the original purpose of surgery, which deals with the digestive tract in a different way in order to limit intake, reduce absorption and consume excess fat from oneself to achieve weight loss. This makes surgery the only long-term effective way to treat morbid obesity. So, does the postoperative remission of blood glucose in type 2 diabetic patients occur in parallel with weight loss? The results of the study are intriguing. Glycemic recovery in diabetic patients after gastric bypass occurs much earlier than significant weight loss, and Rubino reported that patients recovered normal blood glucose levels within a short period of time after gastric bypass, when weight loss was far from satisfactory. The relevant literature shows that the rate of diabetes remission after gastric banding is significantly lower than gastric bypass for the same bariatric surgery. It is suggested that recovery of type 2 diabetes is not directly related to weight loss. There may be a glucose-lowering mechanism other than bariatric.
The intestine-islet axis is a hot spot in metabolic surgery research in recent years. It has been suggested that a variety of hormones secreted by the gastrointestinal tract are related to the regulation of glucose metabolism, including cholecystokinin, gastric inhibitory peptide, glucagon-like peptide-1 , gastric growth-promoting hormone, leptin, peptide, and lipocalin.
There are two main hypotheses for the rationale of surgery.
(1) Duodenal-jejunal hypothesis: Gastric peptide is synthesized and released by K cells in duodenum and proximal jejunum, and there is often excessive secretion of gastric peptide in diabetic patients, which is associated with the occurrence of insulin resistance. After gastric bypass (or duodenojejunostomy), the stimulation of the proximal small intestine by nutrients is reduced or stopped, and the release of gastric peptide by K cells is reduced, thus alleviating insulin resistance, and long-term cure of type 2 diabetes is obtained.
(2) Distal ileum hypothesis: Glucagon-like peptide-1 is synthesized and released by L cells in the distal ileum and colon, which has a pro-insulin secretory effect and can increase islet regeneration and reduce apoptosis. pYY is also a hindgut hormone mainly released by L cells in the distal ileum after meals, which acts on the arcuate nucleus of the hypothalamus to inhibit the release of neuropeptide Y, producing a feeling of satiety, inhibiting gastric emptying and gastrointestinal motility, thus suppressing This suppresses appetite and weight loss. After gastric bypass or biliopancreatic bypass, undigested or partially digested food enters the distal ileum earlier, stimulating L-cells to secrete glucagon-like peptide-1 and PYY, causing an increase in insulin secretion and suppressing appetite, reducing energy intake, and thus lowering blood glucose. One study showed that feeding stimulated increased concentrations of glucagon-like peptide-1 and PYY in patients after gastric bypass, peaking 30 minutes after meals and significantly higher than gastric banding, which is also a bariatric procedure.
Which patients can undergo surgery
Patients can expect better outcomes when they meet the following criteria.
(1) Age 18 to 65 years;
(2) BMI (body mass index) ≥ 27.5 kg/m2 combined with type 2 diabetes;
(3) centripetal obesity, waist circumference ≥ 90 cm in men and ≥ 80 cm in women;
(4) Duration of diabetes <15 years;
(5) good pancreatic islet function.
At the same time, patients and their families are fully aware of the surgical modality for the treatment of diabetes, understand and are willing to bear the risk of potential complications of surgery, understand the importance of postoperative diet and lifestyle changes and are willing to bear them; they can actively cooperate with postoperative follow-up, etc.
From the results of current clinical practice at home and abroad, surgery can not only treat diabetes, but also cure some complications of diabetes and certain metabolism-related complications. For example, the blurred vision caused by diabetic retinopathy can be cured or improved after surgery; the urine protein caused by diabetic nephropathy can disappear or be reduced; the numbness and pain of the limbs caused by diabetic peripheral neuropathy will completely disappear or be relieved; other manifestations of metabolic disorder syndrome, such as obesity, hyperlipidemia, hypertension, respiratory sleep apnea syndrome, etc., are present before surgery except for type 2 diabetes. These metabolic disorder syndromes will disappear or remit after surgery. A growing number of long-term clinical studies are now showing that patients treated with surgery have a significantly lower risk of cardiovascular events, significantly lower mortality, significantly better quality of life, and significantly longer life expectancy compared to patients treated with medications.
Despite all the advantages of surgery for diabetes, the concept of surgery for diabetes is still “little known” in China. Some patients do not understand the principles of surgery, and some patients have some concerns about surgery.
Risk-benefit analysis of surgery
The role of bariatric surgery in the treatment of type 2 diabetes and metabolic syndrome is unquestionable, however, all surgical procedures carry a certain amount of risk, but this risk is only meaningful when compared to the damage caused by diabetes. Risk-benefit assessment is therefore an important issue in the selection of therapeutic surgery. The first concern is the risk of death from the surgery itself. Dimick et al. reported the risk of death from seven common surgical procedures, ranging from hip arthroplasty with a 0.3% mortality rate to craniotomy with a 10.7% mortality rate, with gastric bypass surgery having a mortality rate comparable to that of hip arthroplasty. In contrast, at postoperative follow-up, postoperative mortality was significantly reduced (30% to 90%) compared with nonoperative diabetic patients of the same baseline age and body mass index level. in a retrospective study conducted by Adams et al. in 2007 with an 18-year follow-up, 7925 obese patients who underwent gastric bypass had a mean The risk of total mortality was reduced by 40% over 7.1 years (3.76% and 5.71% per year, respectively; P<0.001); mortality from diabetes-related complications by 92% (0.4% and 3.4% per year, respectively; P=0.005); risk of cardiovascular disease by 56% (2.6% and 5.9% per year, respectively; P=0.006); and mortality from cancer by 60% (5.5% and 13.3% per year, respectively; P= 0.001). This shows that the benefit of reduced postoperative mortality far outweighs the risk of death from the procedure itself, and that bariatric surgery remains an effective pathway for the comprehensive management of metabolic syndrome in obese diabetic patients.
Some patients are concerned about residual gastric problems after gastric bypass. This is a focal point of concern for both patients and physicians. Theoretically, most of the gastric bodies that are left open after gastric bypass will have some degree of atrophy, but a large number of clinical studies at home and abroad have shown that the incidence of gastric disease does not increase after gastric bypass.
Some patients are concerned that reduced meal intake and absorption after gastric reduction may cause malnutrition and persistent weight loss. Gastric bypass is a reconstructive surgery of the digestive tract, which changes the flow of food and reduces the digestive and absorption area of food after surgery, and the absorption of some substances (mainly vitamins and certain minerals such as calcium and iron) will be affected. Nutritional supplementation for postoperative patients is the most important issue, and patients just need to have a reasonable diet under the guidance of doctors. Patients do lose weight after gastric bypass surgery, but not endlessly. Clinical practice shows that after surgery when the excess weight of obese patients is lost, the patient’s weight is actually at a plateau, that is, fluctuating at a relatively normal weight level.
Some patients are concerned that they will lose strength after surgery and that it will affect their work and life. In fact, diabetic patients suffer from hyperglycemia and certain complications before surgery, and most patients do not have a high quality of life. After surgery, with the improvement of hyperglycemia and the reduction of excess weight, patients will have a significant improvement in both mental outlook and physical ability than before surgery, and not only will they not suffer from physical stamina, but they will be better than before surgery.
It is well known that the treatment of diabetes is a lifelong issue, and similarly diabetic patients who undergo surgery require lifelong follow-up. After surgery, diabetic patients have to receive lifelong guidance from their doctors so that they can solve the problems of blood sugar control, nutrition, and prevention and treatment of surgical complications.