How Effective Is Surgery?

The actual weight a patient will lose after the procedure depends on several factors including:

  • Patient's age
  • Weight before surgery
  • Overall condition of patient's health
  • Specific surgical procedure
  • Ability to exercise
  • Commitment to maintaining dietary guidelines and other follow-up care
  • Patient’s motivation and the cooperation of family, friends and associates

Surgery has been found to be effective in improving and controlling many obesity-related health conditions. A study of 500 patients conducted in 2000 showed that 96 percent of certain associated health conditions (back pain, sleep apnea, high blood pressure, diabetes and depression) were improved or even resolved.

For example, many patients with Type 2 diabetes, while showing less overall excess weight-loss, have demonstrated excellent resolution of their diabetic condition, to the point of having little or no need for continuing medication.

In general, the success of weight-loss surgery is sometimes defined as achieving a 50 percent loss or more excess body weight and maintaining that level for at least five years. Clinical data will vary for each of the different procedures mentioned on this site. Results may also vary by surgeon. Ask your doctor for the clinical data stating their results of the procedure they are recommending.

Clinical studies show that, following surgery, most patients lose weight rapidly and continue to do so until 18 to 24 months after the procedure. Patients may lose 30 to 50 percent of their excess weight in the first six months, and 77 percent of excess weight as early as 12 months after surgery.

Another study showed that patients could maintain a 50 to 60 percent loss of excess weight 10 to 14 years after surgery. Patients with higher initial BMI tend to lose more total weight. Patients with lower initial BMI will lose a greater percentage of their excess weight and will more likely come closer to their ideal body weight (IBW). Patients with Type 2 diabetes tend to show less overall excess weight-loss than patients without Type 2 diabetes.

Gastric bypass surgery often helps eliminate many of the medical problems that accompany obesity including :

High blood pressure
Nearly 70 to 80 percent of patients who suffer from high blood pressure and use medications to control it are able to stop taking all meds and have a normal blood pressure, usually within six months after surgery. When medications are still required, dosages can generally be lowered with reduction of accompanying side effects.
Diabetes
About 90 percent of patients with Type 2 diabetes achieve excellent results within a few weeks after surgery. These include reduction and/or complete freedom from all medications, (including insulin injections, normalization of blood sugar levels and Hemoglobin A1C values.) Although the existing complications of diabetes (including neuropathy, vasculopathy and retinopathy) may not be reversed, it’s likely that their progression will slow down when blood sugar levels are maintained at normal values. More and more studies suggest that gastric bypass surgery may be the best available medical treatment for diabetes that currently exists for the seriously obese patient. Abnormal glucose tolerance, or "borderline diabetes," is even more reliably reversed by gastric bypass. Since this condition develops into diabetes in many cases, the operation can frequently prevent diabetes as well.
Heart disease
Major improvements in problems such as high blood pressure, high cholesterol and diabetes suggest that the risk of dying from heart disease may well be reduced in the severely obese patients. In one recent study, the risk of death from cardiovascular disease was profoundly reduced in diabetic patients who are particularly susceptible to this problem. It may be many years before further proof exists, since there is no easy and safe test for heart disease.
Respiratory problems
Improvement in exercise tolerance and breathing ability usually occurs within the first few months after surgery. Often, patients who have barely been able to walk find that they are able to participate in family activities and sports.
Sleep apnea and Obesity Hypoventilation Syndrome
Since these conditions are strongly related to obesity, dramatic resolution occurs as patients lose weight. Many report complete resolution of their symptoms within a year of surgery with cessation of snoring and daytime sleepiness. Many patients who require an accessory breathing apparatus to treat sleep apnea no longer need it after surgically induced weight-loss.
Heartburn (Gastroesophageal Reflux Disease or GERD)
Gastric bypass surgery is described as the ultimate operation for this condition since it results in a dramatic reduction in the size of the stomach and therefore in the amount of acid secreted--the main culprit that causes heartburn. Relief of all symptoms of reflux usually occurs within a few days to weeks after surgery for nearly all patients. There is some emerging evidence that surgery may also reduce long-term complications of reflux disease, including esophageal cancer and stricture formation.
Low back pain, degenerative disk and joint disease
Patients usually experience considerable relief of pain and disability from degenerative arthritis and disk disease and from pain in the weight-bearing joints (hips and knees.) This tends to occur early, with the first 25 to 30 pounds lost, usually within a month after surgery. However, existing complications of degenerative joint disease including nerve irritation or structural damage may not be reversed by weight-loss, and some pain may persist.
High cholesterol
More than 80 percent of patients will develop normal cholesterol levels within two to three months after the operation.
Stress urinary incontinence
This socially embarrassing condition responds dramatically to weight-loss and usually becomes completely controlled. A person who is still troubled by incontinence can choose to have specific corrective surgery later, when the chance of a successful outcome with a reduced body weight.
Shortness of breath and asthma
Most asthmatics find that they have fewer and less severe attacks, or sometimes none at all. When asthma is associated with gastroesophageal reflux disease, it is particularly benefited by gastric bypass.
Gallbladder disease
When gallbladder disease is present at the time of the surgery, it can be cured by removing the gallbladder during the operation. If the gallbladder is not removed, there is some increase in risk of developing gallstones after the surgery, and occasionally, removal of the gallbladder may be necessary at a later time. Generally, gallstone-dissolving medications given in the first six months after gastric bypass surgery prevent this from happening.

Marked improvement in other medical conditions including leg swelling, leg ulcers, pseudotumor cerebri, menstrual irregularities and chronic headaches also occurs after weight-loss surgery.

It’s important to understand that surgery is only a tool to help you achieve permanent weight-loss and the resolution of accompanying illnesses. Surgery plays only a small role in the overall management of obesity. You must make a commitment to a life-long change in your eating and exercise habits after this surgery.