BACKGROUND
The prevalence of obesity and obesity-related Type II diabetes mellitus (T2DM) is rapidly increasing among the Chinese, presenting among younger, lower BMI individuals than their Caucasian counterparts. Metabolic surgery, including Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG), is the only proven means of sustained weight loss and T2DM remission/control but data are limited in Asian populations.

AIMS
Assess impact of RYGB and SG on health outcomes during the first year after surgery in obese T2DM subjects across multiple centers in China.

METHOD
Subjects underwent laparoscopic RYGB or SG at six Chinese clinical sites from August 2014 through January 2016 and returned for follow-up during the first year after surgery. Outcomes from the study will be reported periodically over the 5 years of follow-up.   

RESULTS
A total of 101 subjects underwent 76 RYGB or 25 SG procedures (Table 1).

Table 1. Demographic & Operative Characteristics (Mean±SD)
N, subjects	                                        101
Female, n (%)	                                53 (52.5%)
Age, years	                                        37.1±9.7
Time since T2DM diagnosis, years	3.4±2.7 (range: 0-9 years)
RYGB, n	                                                76
Operative time, hours                        2.15±0.61
SG, n	                                                25
Operative time, hours                        1.41±0.32

Metabolic outcomes at one-year follow-up were available for 92 subjects and showed substantial improvement (Tables 2 and 3).

Table 2. Metabolic Outcome Measures			
                                                RYGB (n=69)	                                          SG (n=23)
(Mean±SD)	                        Baseline        1-yr Change   p-value	  Baseline	 1-yr Change   p-value
Body weight, kg	                97.7±17.7      -24.9±10.8	<0.001	  100.2±15.8	 -27.1±10.5	  <0.001
body weight change, %	-	                 -25.2±9.1	<0.001	   -	                 -26.6±7.7	  <0.001
BMI, kg/m2	                        34.5±5.0	 -8.8±4.0	<0.001	  35.6±4.5	 -9.6±3.4	  <0.001
Systolic BP, mmHg	        134.7 ± 13.9	 -15.1±17.4	<0.001	  134.2±14.3	 -12.7±12.5	  <0.001
Diastolic BP, mmHg	        83.5±9.0	 -9.7±12.8	<0.001	  85.8±10.2	 -10.7±13.3	  <0.001
HbA1c, %	                        8.3±1.7	         -2.5±1.8	<0.001	  7.6±1.6	 -2.0±1.5	  <0.001
FPG, mmol/L	                        9.29±3.24	 -3.69±3.46	<0.001	  8.80±3.67	 -3.60±-3.61	  <0.001
Triglycerides, mmol/L         2.88±3.00	 -1.84±2.92	<0.001	  2.14±1.61	 -1.11±1.46	  0.001
Total Cholesterol, mmol/L	4.94±1.65	 -0.93±1.79	<0.001	  4.89±1.09	 -0.18±1.01	  0.392
LDL-C, mmol/L	                2.83±0.87	 -0.49±0.93	<0.001	  3.06±0.79	 -0.20±0.73	  0.196
HDL-C, mmol/L	                0.94±0.22	 +0.28±0.23	<0.001	  0.95±0.17	 +0.44±0.25	  <0.001

Table 3. Diabetes Control and Medication Use		
	                                                               RYGB (n=69)	                SG (n=23)
% Subjects	                                               Baseline	12 months	Baseline	  12 months

Glycemic Control				
HbA1c ≥7.0%	                                        81.2	 5.8	                65.2	   0.0
HbA1c ≥6.0% to <7.0%                              13.0	 21.7	        17.4	   17.4
HbA1c <6.0%	                                        5.8	         72.5	        17.4	   82.6

Medication Use				
Any anti-hyperglycemic agents (AHAs)	84.1	27.5	         52.2	   30.4
Insulin ± other AHA  	                                43.5	4.3	                 30.4	   4.3
Any anti-hypertensive agents	                29.0	10.1	         17.4	   13.0
Any dyslipidemic agents	                        15.9	4.4	                 0.0	           0.0

Among the 69 subjects with a RYGB and 23 subjects with a SG, 41 (59.4%) and 13 (56.5%) had a BMI <35 kg/m2 at baseline, respectively. This lower BMI cohort compared to the higher BMI cohort had slightly less weight loss (22.6% versus 28.9% for RYGB and 24.8% versus 29.0% for SG) and comparable glycemic control throughout the 1-year of follow-up (HbA1c of 5.9% versus 5.5% for RYGB and 5.7% versus 5.4% for SG). 

Overall, in the 101 subjects that underwent a procedure, 100 subjects (99.0%) experienced a total of 523 adverse events (AEs) through one-year of follow-up after the completed procedures, including 63 subjects (120 AEs) with gastrointestinal disorders. Within the first 30 days after the completed procedures, eighty subjects (79.2%) experienced a total of 237 adverse events (AEs), including 53 subjects (80 AEs) with gastrointestinal disorders. There has been one death approximately 22 months after RYGB due to cerebral hemorrhage in a patient with end stage renal disease. The death was not considered related to the RYGB procedure.

DISCUSSION
The one-year outcomes show substantial improvement across in glycemic control, dyslipidemia, and hypertension with a concurrent reduction in medication for RYGB and in glycemic control and concurrent reduction in medication for SG. Outcomes in this Asian population are consistent with other studies in the field for both safety and effectiveness.

Prospective, multi-center study of metabolic surgery in obese type II diabetics in China: 1-year follow-up assessment