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Bariatric Surgery


Benefits of surgery include both weight loss and improvement in health problems.

Weight Loss After Roux-en-Y Gastric Bypass Surgery

Most patients lose between 60% and 85% of their excess body weight at by 1 year after gastric bypass surgery. The average excess weight loss at one year among the more than 2,200 patients who have undergone gastric bypass at West Penn Bariatric Surgery Center is 75%.

Take, for example, a person 5’7” tall. This person's ideal weight is 155 pounds (BMI 24). If this person 5’7” tall has an actual weight of 355 pounds, this person has an excess weight of 200 pounds (355 – 155 = 200).

  • After gastric bypass surgery, this person would be expected to lose about 75% of the excess 200 pounds, or about 150 pounds; this patient would be expected to weigh about 205 pounds by 1 to 1½ years after surgery.
  • If this same patient loses only 50% of the excess 200 pounds, this person would lose 100 pounds and would then weigh 255 pounds.
  • If this person loses 100% of excess weight (all 200 pounds of excess weight), this person would weigh 155 pounds.

Weight loss occurs rapidly after gastric bypass. Woman, on average, lose about a pound a day within the first 2 to 3 weeks after gastric bypass. Men tend to lose about 2 lbs. a day during the first few weeks after gastric bypass. Typically, patients will lose about 20% of their excess weight at 2 months after gastric bypass, 30% at 3 months, 40% at 4 months, until the one year result of 60 to 85% excess weight loss at one year.

Patients who gained their excess weight after age 18 often achieve the weight of their high school years. Those who were very overweight in high school usually achieve a lower weight than their high school weight.

About 9 out of 10 patients will lose more than 50% (half) of the excess weight by the end of the first year after gastric bypass surgery.

About 1 out of 10 patients will lose less than 50% of the excess weight, although those who lose less still have improvement in weight-related health problems such as diabetes and high blood pressure.

Below is a chart of the weight loss results of the first 800 laparoscopic Roux-en-Y gastric bypass patients at West Penn Hospital

weight loss chart

Patients may gain weight after their initial weight loss if they are not compliant with their diet, exercise, and follow-up regimens. Weight loss depends on numerous factors, including follow-up, following dietary guidelines, and exercise. Patients need to follow-up with us for guidance (or possible revisional surgery if necessary) to get the best results.

Long-term weight losses (10 to 14 years) after gastric bypass surgery average 50% to 60% of excess weight. Some patients will lose and keep all (100%) of their excess weight, while others can gain all of their weight back (0% excess weight loss).

These variable results make it clear that gastric bypass surgery is only a “tool” to help patients get a huge “jump-start” to lose excess weight. Patients need to follow strict rules for diet and activity to keep the weight off.

Weight Loss After Adjustable Band

Weight loss results after adjustable banding are very variable. Most patients lose between 25% and 60% of their excess body weight at by 1 to 3 years after adjustable band surgery. The average excess weight loss is typically about 40%. Weight loss occurs at a slower rate than gastric bypass. Younger patients and those with a lower BMI (<45) will typically achieve the best results. Patients must be dedicated and make the lifestyle changes to succeed with laparoscopic adjustable band. Patients who are able to lose weight on a strict diet and exercise are more likely to have good results. Patients unable to lose weight on a strict low calorie diet may not lose much weight.

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High Blood Pressure

Hypertension (high blood pressure) improves in most patients after gastric bypass surgery, often within a few days after surgery.

Hypertension resolves completely in about 75% of patients and is improved in an additional 10%. Some patients may still need medical treatment of their high blood pressure, but with fewer medications than before surgery or at lower doses.

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High Cholesterol and Triglyceride Levels

About 80% of patients who have high cholesterol or triglyceride levels will have normal cholesterol and triglyceride levels within a few months after gastric bypass surgery.

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Diabetes Mellitus

Hormonal (body chemistry) changes occur soon after gastric bypass surgery that lead to improved blood sugar control in diabetic patients. Remission of type 2 diabetes mellitus occurs in about 85% of patients who have undergone gastric bypass surgery. Most patients are able to completely discontinue their diabetic medications soon after gastric bypass surgery, before dramatic weight loss occurs.

Patients who still need medications (including insulin) to control diabetes after gastric bypass surgery find they are able to gain better control of their blood sugars with smaller doses.

It is very important for diabetic patients to monitor their blood sugars daily after gastric bypass surgery, because blood glucose levels can become normal within a few days after surgery. Diabetic patients may be discharged from the hospital on insulin for the first week after surgery. No medical treatment for diabetes can achieve as complete and profound an effect as bariatric surgery

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Heart Disease

Gastric bypass surgery leads to improvements in the major risk factors for heart disease:  high blood pressure, diabetes, and high cholesterol.

Also, weight loss can lead to improvement in cardiac function, because with less weight, the heart does not have to work as hard.

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Respiratory Insufficiency

Patients usually feel an improvement in tolerance for exercise and easier breathing within the first few months after gastric bypass surgery.

Often, patients who have barely been able to walk find that they are able to participate in family activities, even sports activities.

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Sleep Apnea Syndrome

Most patients stop snoring within a few months after weight-loss surgery.

More than 85% of patients who had to use continuous positive airway pressure (CPAP) machines at night before surgery are symptom-free without their machines at one year after surgery.

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Most patients who had asthma before weight-loss surgery find that they have fewer and less severe attacks, or sometimes none at all, as they lose excess weight and fat.

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Gastroesophageal Reflux Disease

Relief of heartburn due to gastroesophageal reflux disease occurs soon after surgery in more than 90% of patients. Patients are placed on a strong antacid (Prilosec) for the first 2 months after surgery. Then, many patients can discontinue this medication.

Patients who smoke or who regularly take nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (brand names such as Advil, Motrin), indomethacin, naprosyn sodium (brand names such as Alleve), or Celebrex may need to continue taking antacid, to prevent gastric ulcer formation.

Patients with a history of Barrett’s esophagus prior to surgery will still need to be monitored by endoscopy after surgery, although this condition improves after gastric bypass surgery.

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Stress Urinary Incontinence

Stress urinary incontinence usually becomes completely controlled without medication as women lose abdominal fat and the pressure of fat on the bladder decreases.

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Low Back Pain, Degenerative Disk Disease, and Degenerative Joint Disease

Patients who have pain and disability from degenerative arthritis in the weight-bearing joints and discs in the back usually notice relief after gastric bypass surgery.

Patients with poor mobility prior to surgery often notice dramatic improvement in their ability to move within a few months after surgery.

Some patients who were not candidates for joint replacement surgery because of excess weight become candidates after their weight-loss surgery.

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Quality of Life

Patients find that they have overall better quality of life after surgery: meeting the challenges (social, emotional, and psychological) that they faced before surgery becomes much easier.

  • Patients begin to get around easier and feel confident in facing certain public situations.
  • Patients feel better about themselves and their self esteem improves.
  • Others take on new hobbies, such as traveling, that they never thought were possible before surgery.
  • Many patients feel they have a “new lease on life”.
  • Patients can wear the clothes they want to wear, not the ones they have to wear.
  • Patients can participate in activities with their families, such as going on amusement park rides, and enjoy everyday activities.
  • Most patients notice improved levels of energy due to their weight loss. They feel they are no longer “carrying around an extra person”.
  • Increased energy, ability to exercise, and ability to participate in sports improve iwth weight loss.

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