Gastric Surgery for Severe Obesity

David L. Gee, PhD

Professor of Food Science and Nutrition

Central Washington University

Carnie WilsonGastroplasty, Aug 1999weight loss ~ 150 lbs

2003 poses for Playboy2005 delivers baby daughter (gained 70 pounds, lost ~ 40

pounds)

Charlie WeissNew England

PatriotsOffensive

Coordinator

Gastric Bypass Surgery

Wt loss = 85 pounds

Surgical complications:

internal bleedingsepsis

nerve damage to lower limbs

Bariatric Surgery TrendsJAMA, 289(14): 1761‑1762, April 9, 2003

• US Bariatric surgeries performed per year– 2001: 47,000– 2002: 63,000– 2003 (projected): 98,000

Bariatric Surgeries

0

5000

10000

15000

20000

25000

12-17 18-34 35-44 45-54 55-64 >65

Age Group

1998

2002

Source: Health Affairs, July/Aug 2005

Criteria for Patient Selection

• Unlikely to lose weight with non-surgical procedure

• BMI > 40

• Have high risk of obesity related problems

• not pregnant or planning pregnancy during weight loss

• Informed of risks, lifestyle effects

Surgical Mechanisms for Weight Loss

• Decrease food intake

• Decrease digestion and absorption of nutrients

Surgery to Decrease Food

Intake• Gastroplasty

–Gastric banding

–Vertical banded gastroplasty

Gastric Banding

Vertical Banded Gastroplasty

Weight Loss Outcomes of Gastroplasty

• 80% lose weight

• 30% achieve normal weight

• some regain some of lost weight

• improves obesity related conditions

• success depends on motivation and behaviors

Risks of Gastroplasty

• vomiting

• erosion of band, breakdown of staple line

• 10-20% require follow-up operations

• 1/3 develop gallstones

Surgery to Reduce Food Intake and Nutrient

Absorption

• Gastric Bypass Surgery–Roux-en-Y Gastric Bypass

Roux-en-Y Gastric Bypass

Outcomes of Gastric Bypass Surgery

• produces more weight loss than gastroplasty

• generally lose 2/3rds of excess weight within 2 years

Risks of Gastric Bypass Surgery

• like gastroplasty

• chronic diarrhea

• nutritional deficiencies–vitamin B-12

–iron

–calcium

Gastric Bypass Surgery Complications: 14-Year Followup

Surgical Complications Number of Patients % of Patients

Vitamin B12 deficiency 239 39.9Readmit for various reasons 229 38.2Incisional hernia 143 23.9Depression 142 23.7Staple line failure 90 15.0Gastritis 79 13.2Cholecystitis 68 11.4Anastomotic problems 59 9.8Dehydration, malnutrition 35 5.8Dilated pouch 19 3.2

Data derived from source (Pories et al.) and modified based on personal communication.Source: Pories WJ, Swanson MS, MacDonald KG Jr, et al. Who would have thought it? An operation proves to be the most effective therapy for adult-onset diabetes mellitus. Ann Surg. 1995;222:339-350; discussion 350-352.

What are the dietary guidelines following bariatric surgery?

JADA 104: 487-488 (2004)

• General guidelines– Eat for >20 min to allow for satiety– Well chewed, small volumes– Liquids ingested well before or after meals– Proteins eaten before fats and carbs

• Nutritional Considerations– Gastric banding: iron & B-12 deficiencies– Gastric bypass: iron, calcium, folate, B-12 deficiencies,

dumping syndrome– Fat malabsorption and lactose intolerance– Dehydration– Vitamin/mineral supplements recommended

Early Mortality Among Medicare Beneficiaries Undergoing Bariatric Surgical Procedures

Flum, D. et al. JAMA. 2005;294:1903-1908

• Subjects: – All fee-for-service Medicare beneficiaries,

1997-2002 • 16,155 patients• Mean age = 47.7 yrs (SD=11.3)• 75.8% female

• Outcome Measures:– 30 day, 90 day, 1 year mortality

Findings: 1. Overall mortality rate at 1 year = 4.6%

2. Mortality rate in men >> women (7.5% vs. 3.7%)

3. Mortality rate in >65 yr >> <65 yr (11.1% vs 3.9%)

Early Mortality Among Medicare Beneficiaries Undergoing Bariatric Surgical

Procedures Flum, D. et al. JAMA. 2005;294:1903-1908

• Conclusions  • Among Medicare beneficiaries, the risk of early

death after bariatric surgery is considerably higher than previously suggested

• Risk of early death associated with advancing age, male sex, and lower surgeon volume of bariatric procedures

• Patients aged 65 years or older had a substantially higher risk of death within the early postoperative period than younger patients.

Conclusions

• Bariatric surgery generally results in– substantial weight loss– Marked improvement in health risks– Improved quality of life

• Bariatric surgery is not risk free– Mortality rate ~5% – Complications and further surgeries– High costs

• Permanent changes in eating/lifestyle– Risks of malnutrition