Association of Bariatric Surgery With Risk of Fracture in Patients With Severe Obesity

Abstract

IMPORTANCE Given the complex relationship between body mass index, body composition, and bone density and the correlative nature of the studies that have established the prevailing notion that higher body mass indices may be protective against osteopenia and osteoporosis and, therefore, fracture, the absolute risk of fracture in patients with severe obesity who undergo either Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) compared with those who do not undergo bariatric surgery is unknown. OBJECTIVE To assess the rates of fractures associated with obesity and compare rates between those who do not undergo bariatric surgery, those who undergo RYGB, and those who undergo SG. DESIGN, SETTING, AND PARTICIPANTS In this retrospective multicenter cohort study of Medicare Standard Analytic Files derived from Medicare parts A and B records from January 2004 to December 2014, patients classified as eligible for bariatric surgery using the US Centers of Medicare & Medicaid criteria who either did not undergo bariatric surgery or underwent RYGB or SG were exactly matched in a 1:1 fashion based on their age, sex, Elixhauser Comorbidity Index, hypertension, smoking status, nonalcoholic fatty liver disease, hyperlipidemia, type 2 diabetes, osteoporosis, osteoarthritis, and obstructive sleep apnea status. Data were analyzed from November to December 2019. EXPOSURES RYGB or SG. MAIN OUTCOMES AND MEASURES The primary outcome measured in this study was the odds of fracture overall based on exposure to bariatric surgery. Secondary outcomes included the odds of type of fracture (humerus, radius or ulna, pelvis, hip, vertebrae, and total fractures) based on exposure to bariatric surgery. RESULTS A total of 49 113 patients were included and were equally made up of 16 371 bariatric surgery-eligible patients who did not undergo weight loss surgery, 16 371 patients who had undergone RYGB, and 16 371 patients who had undergone SG. Each group consisted of an equal number of 4109 men (25.1%) and 12 262 women (74.9%) and had an equal distribution of ages, with 11 780 patients (72.0%) 64 years or younger, 4230 (25.8%) aged 65 to 69 years, 346 (2.1%) aged 70 to 74 years, and 15 (0.1%) aged 75 to 79 years. Patients undergoing RYGB were found to have no significant difference in odds of fractures compared with bariatric surgery-eligible patients who did not undergo surgery. Patients undergoing undergone SG were found to have decreased odds of fractures of the humerus (odds ratio [OR], 0.57; 95% CI, 0.45-0.73), radius or ulna (OR, 0.38; 95% CI, 0.25-0.58), hip (OR, 0.49; 95% CI, 0.33-0.74), pelvis (OR, 0.34; 95% CI, 0.18-0.64), vertebrae (OR, 0.60; 95% CI, 0.48-0.74), or fractures in general (OR, 0.53; 95% CI, 0.46-0.62). Compared with patients undergoing SG, patients undergoing RYGB had a significantly greater risk of total fractures (OR, 1.79; 95% CI, 1.55-2.06) and humeral fractures (OR, 1.60; 95% CI, 1.24-2.07).

Examination of Elective Bariatric Surgery Rates Before and After US Affordable Care Act Medicaid Expansion

“…We examined a comprehensive set of bariatric surgeries that included Roux-en-Y gastric bypass, vertical sleeve gastrectomy, and gastric banding, and excluded procedure codes that indicated possible revision surgeries or treatment of complications from an earlier index bariatric surgery. 29 , 30 , 31 We excluded cases with evidence of possible surgical indications other than obesity, such as abdominal procedures for malignant neoplasms and abdominal ulcers. 29 To identify elective surgeries, we excluded patients admitted through the emergency department.…”

Fracture Risk After Bariatric Surgery: A Systematic Literature Review and Meta-Analysis

“…It is worth noting, however, that most patients included in these 3 studies underwent restrictive surgery. 15,19,25 Two more recent retrospective cohort studies 14,18 also did not find an increased risk of fractures after bariatric surgery compared with the population with obesity eligible for bariatric surgery. Furthermore, they suggested that surgery reduces the risk of fractures, especially in patients undergoing vertical gastrectomy.…”

“…Among the included studies, 12 were observational studies (10 cohort studies, 1 case-control study, and 1 case series) 5,6,[13][14][15][16][17][18][19][20][21][22] and 3 interventional clinical studies (2 randomized and 1 nonrandomized). [23][24][25] Most of the studies were conducted in the United States, with the majority of participants being premenopausal women.…”

“…Ten observational studies 6,[13][14][15][16][17][18][19][20][21] were included in the metaanalysis to compare the fracture risk between the surgical (N ¼ 116.205) and nonsurgical (N ¼ 134.637) groups. Of all 10 studies, there were 3.512 fractures in 138.562 subjects who underwent bariatric surgery versus 3.515 fractures in 156.994 control subjects.…”

Testosterone Therapy for Prevention and Treatment of Obesity in Men

“…135 Bariatric surgery appears to be a particularly strong risk factor for BMD loss 136,137 and fractures. [138][139][140] A 7-year prospective study after RYGB (baseline mean age 43 -8 years, BMI 42 -6 kg/m 2 ) found continuous decline in BMD and deterioration of bone microarchitecture, as well as reduced estimated bone strength compared with baseline and 2 years postsurgery. 137 A meta-analysis concluded that bariatric surgery significantly increases fracture risk.…”