Pancreas Transplant cures Diabetes Mellitus
March 19, 2020
Diabetes mellitus is a chronic disease, which occurs when the pancreas does not produce enough insulin (type 1 diabetes), or when the body cannot effectively use the insulin it produces (type 2 diabetes). Diabetes is fast gaining the status of a potential epidemic in India, with 79.4 million predicted to be diabetic by 2030, which is the largest in the World. Worryingly, Indians get diabetes on an average 10 years earlier than their Western counterparts and approximately 55% of diabetics are in the most productive years of their lives i.e. before the age of 50 years. The risk factors peculiar for devloping diabetes among Indians include high familial aggregation (strong family history), central obesity (excessive fat accumulation in the abdominal area), insulin resistance (when cells don’t respond to insulin and can’t easily take up glucose from the blood) and life style changes due to urbanization.
Diabetes in the long-term affects our blood vessels and nerves and therefore can affect any part of the body. Diabetic complications will usually take a number of years of poorly controlled diabetes to develop. Progressive damage to the smaller (microvascular) and larger (macrovascular) blood vessels within the body affects vital tissues and organs such as kidneys, heart, brain, eyes and nerves. This results in various complications such as kidney failure needing dialysis/transplantation (nephropathy), heart attack, stroke, impairment or loss of vision (retinopathy) and damage to nerves commonly leading to poor sensation in feets (neuropathy). Sometimes having low blood sugars without any warning (hypoglycemic unawareness) may put the diabetic at risk of having major life threatening events, if they are unable to obtain immediate medical assistance. The life expectancy in patients with diabetes is reduced by up to 15 years predominantly due to damage to the heart and blood vessels (cardiovascular disease).
The management of diabetes requires continuing medical care and patient self- management to prevent acute complications and to reduce the risk of long-term complications. The goals of management are to reduce micro- and macrovascular complications by keeping strict control of glucose levels, maintaining normal blood pressure and cholesterol levels, smoking cessation and regular exercises. Number of different insulin pumps and continuous glucose monitoring technologies are currently available in the market, which deliver insulin continuously throughout the day and attempts to mimic the normal pancreas’s release of insulin. However, the disadvantage with these are their cost, risk of catheter site infections, diabetic ketoacidosis (dangerous condition with body acid accumulation due to lack of insulin) from pump malfunction or absorption problems and the need for regular feeding of glucose levels into these devices for appropriate functioning. The goal of these insulin therapies are to achieve optimal glucose control, which currently is unrealistic due to absence of biofeedback within these devices, which are further complicated by changes in glucose profiles based on individual’s varying diets, activity levels and the time of the day. The only treatment approach that can mimic physiological glucose control is the pancreas or islet transplant. The latter involves transplanting cells that produce insulin, but is not widely practised due to their poor long-term function and due to shortage of donor organs, as a single islet transplant will need two and half full pancreases to isolate enough cells to inject.
A pancreas transplant is a surgical procedure to place a healthy pancreas from a deceased donor into a person whose pancreas no longer functions properly. These donors are people who have suffered irreversible brain damage, usually as a result of an brain injury. A successful pancreas transplant can help the patient to achieve normal glucose levels, that they will no longer need to inject insulin. Since the first pancreas transplant in 1966 at the University of Minnesota, USA, there has been rapid increase in the number of pancreas transplants world-wide. However, only a handful of centres perform pancreas transplants in India.
There are three types of pancreas transplants. More than two-thirds of pancreas transplants worldwide are performed combined with a kidney transplant for people whose kidneys have been damaged by diabetes. This is done for patients who either have already started dialysis or are nearing dialysis. Both the pancreas and kidney are usually obtained from a deceased donor. In some instances, the kidney can be obtained from a living donor and transplanted simultaneously with pancreas obtained from deceased donor. The second type of transplant is pancreas after a kidney transplant. This is done for patients with diabetes who have already had a kidney transplant (from a living or deceased donor). This could also be the case in those who have had a pancreas and kidney transplant, but the pancreas fails, hence necessitating a re-transplant. The third and the uncommon transplant is to transplant pancreas alone. This is usually done for diabetic patients who experience erratic blood sugar control (such as hypoglycemic unawareness) despite taking insulin. These patients have normal or near normal kidney function.
Following pancreas transplant, the patient will no longer need insulin shots or regular blood sugar checks, able to eat a regular diet, be more active and independent. If they also get a kidney transplant, then they can free themselves from dialysis, which offers them freedom from dietary and fluid restrictions, which patient’s would have had to follow before their transplant. However, not all people with diabetes are suitable for a pancreas transplant because of the need to be in relatively good health to have this major operation. All patients with diabetes being considered for pancreas transplant will need to have a number of pre- operative investigations to confirm their suitability to undergo the procedure. The most important of these investigations is to ensure there is no silent heart disease, which is common in diabetes patients. Hence, cardiovascular (heart and blood vessels) investigations are more rigorously checked for pancreas transplant recipients.
The main aim of a pancreas transplant or a combined pancreas and kidney transplant is to improve both the quality and the length of patient’s life. Diabetes causes a number of life threatening complications which may well be reversed or halted as a result of having a pancreas transplant. The common diabetes related complications which have been shown to either reverse completely or stop progressing are the damage to the kidneys, damage to eyes and damage to nerves. However the reversal is usually seen following atleast two years of a successful functioning pancreas transplant. Having a successful pancreas transplant will reduce the on-going damage to the blood vessels caused by the high levels of blood sugar. As a result, if you have had a successful pancreas transplant you are likely to live longer and have less chances of further heart related problems or stroke that may affect your lifespan. Also, patients are likely to have the kidney transplant work much longer if performed as a combined transplant with a pancreas, than as an isolated kidney transplant alone.
There are no outcome data from India to report on patient survival or pancreas graft survival after transplantation. From the UK data, one-year following pancreas transplant, 97% of patients (97 out of 100) are still alive and at five-years 90% of patients are still alive (90 out of 100). With respect to the transplanted pancreas functioning effectively, after one- year 90% (90 out of 100) and after five-years 78% (78 out of 100) of transplants are still working. In case, if the type 1 diabetic patient remains on dialysis and does not get transplanted with either pancreas or kidney, then their one-year risk of dying is nearly three times more than those transplanted. If they live more than one year, their risk of dying is nearly six times more compared to those transplanted. Similarly, the chances of a diabetic being alive at 25 years after a combined pancreas and kidney transplant is 70% versus 27% in case of a kidney transplant alone.
Pancreas transplantation for treatment of diabetes has evolved significantly since its inception in 1960’s. Most pancreas transplant recipients find the transition for transplantation easier than continued insulin therapy. There is enough compelling evidence that pancreas transplant is not only acutely life-enhancing, but also life-saving. Although other complementary therapies are currently actively being investigated for the treatment of diabetes such as implantable insulin pumps, gene therapy and artificial pancreas, there is currently none proven to be more beneficial than a pancreas transplant. It goes without saying that pancreas transplant offers the ‘best medical therapy’ for type 1 diabetes and selected type 2 diabetes patients.