Influence of Age on Sleeve Gastrectomy Results

Abstract

Introduction:

Sleeve gastrectomy (SG) has been a booming technique for 10 years. Bariatric surgery in patients over 50 years can be an effective solution on weight loss and comorbidities. The association with the nutritional and psychological care is essential to allow a true change of life mode. We are studying the mid-term (3-year) outcomes after SG in patients over 50 years of age.

Methods:

This retrospective study analyzes patients treated between January 2011 and December 2013. The 129 patients were divided into three groups: under 35 years (n = 52), 35–50 years (n = 49), and over 50 years (n = 28).

Results:

The excess weight loss at 3 years were 75% for the under 35 years, 82% for the 35–50 years, and 69% for the over 50 years. Follow-up compliance at 3 years was 66%, 68%, 75%, respectively. Comorbidities were improved in all three groups with no significant difference for each comorbidity.

Conclusion:

SG is an effective technique on weight and comorbidities. The results at 3 years are similar in patients over the age of 50 who seem more able to follow up and change lifestyle.

Introduction

The prevalence of overweight and obesity in adults in France is 50%. However, 15% of adults are considered obese, and the obesity rate has increased by one-third since 2000.¹Sleeve gastrectomy (SG) is a rapidly expanding technique that provides good results on weight loss and resolution of comorbidities after several years of follow-up, including in high-risk and elderly patients.² As the population ages, an increasing number of older people are affected by obesity, so its management plays an important role in improving comorbidities and quality of life in this age group.

The majority of patients selected for surgery are under 50 years, while the prevalence of obesity is higher in older age groups. However, although SG is not more risky in the elderly population, its results on weight loss and comorbidity are less well-known.^3–5 This study evaluates the mid-term (3-year) results of SG by comparing three age groups: under 35, 35–50, and over 50 years.

Methods

All patients operated on SG were reviewed retrospectively between January 2011 and December 2013. All patients were operated according to the High Authority's guidelines: Body mass index (BMI) ≥40 kg/m² or a BMI ≥35 kg/m² with comorbidities.⁶ Patients were subdivided into three age groups: group I, <35 years; group II, 35–50 years; and group III, >50 years. Excess weight loss (EWL) was used to compare the weight loss results before and after the operation. A BMI of 25 kg/m² was considered the ideal weight. According to the criteria of Reinhold, we considered surgery as a failure if patients had less than 50% of EWL. The analysis focused on weight loss and improved obesity-related comorbidities at 3 years postoperatively.

Statistical methods

Data are presented as mean (standard deviation) or absolute (%) as appropriate. The chi-squared (χ²) test was used to analyze qualitative data and compare weight loss in patients in the three groups. The analysis of variance was used to compare mean anthropometric values between the three groups. Multiple regression techniques were used to analyze the influence of age and initial BMI on the loss of excess weight, with a significance level of 95%. The significance threshold was set at P = .05.

Results

Of the 152 patients who underwent SG between 2011 and 2013, 129 were included in our study, 19 patients were excluded due to their history of gastric banding and 2 because of their history of sleeve. Two patients were excluded due to a new surgery within 3 years: one was operated at 2½ years of a bypass for a disabling gastroesophageal reflux, the other of a gastro-jejunal anastomosis for the treatment of a chronic fistula. Women are in the majority (women = 115 patients, 87.8%). The mean age was 39 years (range 18–69), the preoperative weight was 115.2 kg (77–198 kg), and the mean BMI was 42.6 kg/m² (35–71.5 kg/m²). Patients were divided into three predefined age groups: age <35 years (n = 52); age between 35 and 50 years (n = 49); and age >50 years (n = 28). The respective mean weight and BMI for the three groups were 118.1 kg (77–197) and 43.4 kg/m² (35–71.5) for the young group, 114 kg (87–198) and 42.1 kg/m² (35–68.5) for the middle age group, 113 kg (94–158) and 42.5 kg/m² (35–56.8) for the oldest group. The descriptive data are summarized in Table 1.

Table 1.

Patient Demographics and Preoperative Comorbidities

	Mean (range) (n = 129)	<35 Years old (n = 52)	35–50 Years old (n = 49)	>50 Years old (n = 28)	P Value
Age (years)	39 (18–69)	28 ± 3.9	42 ± 5.8	54 ± 3.4
Female, n (%)	115 (87.8%)	47 (90.3%)	43 (88%)	23 (82%)	.67
Weight (kg)	115.3 (77–198)	118.1 (77–197)	114 (87–198)	113 (94–158)	.4942
BMI (kg/m²)	42.6 (35–71.5)	43.4 (35–71.5)	42.1 (35–68.5)	42.5 (35–56.8)	.3166
Type II diabetes	21 (16%)	3 (5.76%)	10 (20%)	7 (25%)	.6402
Hypertension	13 (9.9%)	2 (3.8%)	4 (8%)	6 (21%)	.095
Hyperlipidemia	7 (5.3%)	0 (0%)	3 (6%)	3 (11%)	.4106
Obstructive sleep apnea	45 (34.3%)	15 (28.8%)	15 (31%)	12 (43%)	.8460
Joint pain	13 (9.9%)	5 (9.6%)	3 (6%)	5 (18%)	.2877
Gastroesophagieal reflux disease	32 (24%)	9 (17%)	15 (30%)	8 (28%)	.46

BMI, body mass index.

At the 3-year follow-up, the mean percentage of EWL was 76.6% ± 30.7%. The weight results are shown in Table 2. The EWL average was 75.6% ± 31.2% in the young, 82.3% ± 31% in the 35–50 years group, and 69.28% ± 28.7% in the oldest patient group (P = .1266). At 3 years (Table 3), the overall success rate (patients with EWL >50%) was 75.75% in the youth group, 76.19% in the middle-aged, and 80.95% in the highest age group (P = .8961). Table 4 shows a further analysis of the 17 patients in the three groups who were in objective failure (with EWL <50%) according to BMI groups (<40 kg/m², 40–50 kg/m², and >50 kg/m²), there was no significant difference between BMI groups (P = .3540). There is therefore no influence of age or initial BMI on the EWL at 3 years after surgery. Adherence to follow-up is defined by carrying out a consultation at 3 years after telephone call. It is 66%, 78%, and 75% respectively for the three age groups (P = .4802).

Table 2.

Status of Body Weight Characteristics and Follow-Up Compliance at Three Years

	Total n = 129	<35 Years old n = 52	35–50 Years old n = 49	>50 Years old n = 28	P Value
% Excess weight loss	76.6 ± 30.7	75.6 ± 31.2	82.37 ± 31.0	69.28 ± 28.7	.1266
Follow-up compliance	88 (68%)	34 (66%)	33 (78%)	21 (75%)	.4802

Table 3.

Excess Weight Loss Above and Below Fifty Percent at Three Years

	Total	<35 Years old	35–50 Years old	>50 Years old
n	129	52	49	28
Lost to follow-up	41 (32%)	18 (34%)	16 (22%)	7 (25%)
EWL <50%	17 (19%)	8 (24.24%)	5 (23.8%)	4 (19%)
EWL >50%	72 (80.89%)	25 (75.75%)	16 (76.19%)	17 (80.95%)

Chi-squared test. P value = .8961.

EWL, excess weight loss.

Table 4.

Patients with Excess Weight Loss Less Than Fifty Percent Per Body Mass Index at Three Years

	Total	<35 years	35–50 years	>50 years
BMI <40	4	2	2	0
BMI 40–50	11	5	3	3
BMI >50	3	1	0	2
Total	18	8	5	5

Chi-squared test, df 4.405. P value = .3540.

BMI, body mass index.

As shown in Table 1, rates of type 2 diabetes (16%), high blood pressure (9.9%), obstructive sleep apnea syndrome (34.3%), joint pain (9.9%), and gastroesophageal reflux disease (24%) were higher in the highest age group but without significant difference. During the 3 years of follow-up, there was a significant improvement in all comorbidities, but no difference in outcomes between age group (Table 5). Antidiabetic drugs were reduced or eliminated in 85% of cases, and 41% no longer needed or were able to decrease their antihypertensive drugs. In addition, 100% of patients with sleep apnea were able to stop using their positive pressure devices with a decrease in the number of episodes of apnea. Comorbidities, such as joint pain and dyslipidemia were improved or resolved in 100% and 84% of patients. Gastroesophageal reflux was improved in 55.2% of cases, but 14% of patients experienced de novo post-operative gastroesophageal reflux (Table 6).

Table 5.

Comorbidity Resolution and Improvement at Follow-Up

	Total			<35 years			35–50 years			>50 years
	Number of patients	Resolution and improvement	% change	Number of patients	Resolution and improvement	% change	Number of patients	Resolution and improvement	% change	Number of patients	Resolution and improvement	% change	P Value
Type II diabetes	20	17	85	3	3	100	10	9	90	7	6	85	.56
Hypertension	12	5	41	2	1	50	4	2	50	6	2	33	.59
Hyperlipidemia	6	6	100	0	0		3	3	100	3	3	100	1
Obstructive sleep apnea	44	44	100	17	17	100	15	15	100	12	12	100	1
Joint pain	13	11	84	5	3	60	3	3	100	5	5	100	.71
Gastroesophageal reflux disease	32	18	55.2	9	5	55	15	8	53	8	5	62.5	.4

Table 6.

Gastroesophageal Reflux Disease Evolution

	Total (n = 129)	<35 years (n = 52)	35–50 years (n = 49)	>50 years (n = 28)	P Value
Preoperative GERD	32 (24%)	9 (17.3%)	15 (30.6%)	8 (28.5%)	.46
Postoperative GERD	30 (23%)	10 (19.2%)	14 (28.5%)	9 (32.1%)	.54
Postoperative GERD de novo	18 (14%)	6 (11.5%)	7 (14.2%)	6 (21.4%)	.69

GERD, gastroesophageal reflux disease.

Discussion

In the 70s, gastric bypass appeared to be inappropriate for the treatment of morbid obesity in patients over 50 years of age, and the National Institutes of Health set the age limit for this surgery at age 55. However, although time has passed and significant advances in laparoscopic bariatric surgery have been made, little has changed on the indications of this surgery in elderly patients.

Bariatric surgery is an effective and proven therapy for long-term weight loss in morbid obese, resulting in reduced mortality and improved quality of life.^7,8 SG has gained popularity due to its relative technical simplicity and reliability compared with other bariatric surgery procedures. Indeed, its results on weight loss are better than that of the adjustable gastric band and its complications lower than that of gastric bypass in Y.^9,10

The population aged over 50 years is growing rapidly, leading to an increase in the problems associated with obesity and its comorbidities and therefore a reduction in the life expectancy of its patients. The improvement of co-morbidities and the reduction of drug use is significant after bariatric surgery in elderly subjects who have sufficient weight loss.¹¹ In addition, elderly patients do not appear to have higher rates of complications, and have a mortality rate comparable to that of younger patients.¹¹ As a result the demand for bariatric surgery for these patients is increasing. Between 2005 and 2009, the number of patients in demand for bariatric surgery rose from 1.5% to 4.8%.¹¹ Other studies have reported rates of 4.2% and 2.7% in 2004, which rose to 10.1% in 2014 for patients over 60 years.^12,13

Our study revealed that 21% of operated patients are over 50 years of age, which is comparable to van Rutte et al.'s report in 2013, where 16% of SG patients were over 55 years of age.¹⁴

Previous studies have shown good results in terms of EWL, improvement in quality of life, and improvement in co-morbidities with decreased consumption of medications after bariatric surgery in the elderly.^3,12,13,15 The efficacy is comparable for the treatment of high blood pressure, diabetes, sleep apnea, and hypercholesterolemia between young patients and older patients. However, not all studies classify people in the same way, the definition of the “elderly” patient in bariatric surgery is variable: more than 50 years, or more than 55 years or even more than 70 years.¹¹ Aged 55 has often been used to define the “elderly” group, this threshold is low compared with that used for nonbariatric surgery.^13,15–17 This may be due to the need to have an evaluation of the effectiveness of this long-term surgery on weight loss and improved comorbidities. We chose a threshold of 50 years because recommendations limit the indications of surgery to 65 years, which balances the three age groups. Moreover, in obese patients the aging process is affected. In fact, physiological aging linked to advanced age is compounded by invalidating health problems and stigmatization and withdrawal, which can alter the process of aging. Obesity leads to an acceleration of neurodegenerative phenomena and cognitive decline linked to aging as early as 50 years.¹⁸ Similarly, muscle aging and sarcopenia corresponding to a decrease in muscle mass, an alteration of the muscle composition with infiltration of fatty tissue and fibrosis and an alteration of the muscular innervation is significant from the age of 50 years.¹⁹

Few studies have compared the results of SG between different age groups. Our center has been performing SG surgery since 2007 but with a sharp increase in cases since 2011. This study shows that the results of the 3-year SG on weight loss are similar in patients over 50 compared with the results in younger patients.

The effectiveness of bariatric surgery has been studied in elderly patients. For example, Robert does not find that age is a predictor of gastric bypass failure at 1 year.²⁰ Other studies have found a lesser loss of excess weight in older patients compared to the patient under 45 years.^{13,16,21–23} This lower result would be according to the authors because of a lower metabolic expenditure associated with the presence of sarcopenia in older patients. In the Giordano and Victorzon study, which used a threshold of 55 years, there was no difference in BMI, total weight loss, and EWL after 24 months of follow-up in operated bypass patients.²⁴

In a recent study by Burchett et al., there was no significant difference in weight loss and improvement in comorbidities between older and younger age groups.²⁵ Patients aged over and under 62 had comparable results with total weight loss at 20% and a 10-point improvement in BMI after 3 years of postoperative follow-up.²⁵ Another recent study compares patients over 60 years of age with those under 50 years of age, 22 months after SG, the youngest group shows the best result on weight loss expressed as a percentage of BMI loss. This study does not analyze patients between the ages of 50 and 60 to make a clearer distinction,²⁶ suggesting that the 55-year threshold is the most appropriate.

There is not much study with a long-term follow-up comparing the results according to age. Sugerman et al. showed that older patients had better follow-up than younger patients (58% versus 46%) and that weight loss results (as a percentage of BMI loss) were better in older patients (66 ± 26 versus 56 ± 25).¹³ This better adherence to follow-up is a known factor in explaining improved weight loss and comorbidity outcomes in older patients.²⁷ Keren et al. finds better efficacy of SG at 5 years in patients over 55 years (EWL 52.1% versus 41.3%), it explains it by a better adhesion to the follow-up in this group of patients (47% versus 22%).²⁸ Frutos et al. shows that in the group over 55 years weight loss and improvement of comorbidities leads to an improvement in the quality of life superior to the younger patient. With a follow-up of 36 months, the weight results are similar between the two groups.¹⁷ As evidenced by these studies, the key to the long-term success of SG appears to be a change in lifestyle. A good result in terms of weight loss at 5 years is associated with a successful lifestyle change corresponding to an improved knowledge of good eating habits and their practice and an increase in the practice of physical activities.²⁹

Lifestyle changes have often been promoted to explain these better outcomes in older patient groups. Therapeutic interventions in diabetes patients (Action for Health Diabetes) are more effective in elderly patients to improve hypercholesterolemia.³⁰ Karlsen et al. also showed that age was a predictor of better weight loss.³¹ In the diabetes prevention program, a higher age and an increase in physical activity are associated with a better result on weight loss with a target of 7% total weight loss.³² Another article finds that 60% of patients over 65 years reach the target of a total weight loss of 7% compared to only 43% of patients under 45 years of age.³³

The good results in the older population can be explained by the fact that these patients are more aware of the negative consequences induced by obesity on their health. This makes them more likely to have a better motivation to change lifestyle.³⁴ Younger patients can be monopolized by everyday life, their work, their family life with the burden of children, which could limit their ability to change lifestyle. Older patients may have more time, be retired, have no dependent children, which allow them to be more free to provide medical follow-up and devote themselves to changing their eating habits.

The population older than 50 years had a higher comorbidity rate without reaching the threshold of significance. Surgery significantly improved these comorbidities in comparable proportions to other studies.^3,12,13,15 The good improvement of these comorbidities at 3 years postoperative highlights the advantage of SG in older patients.

This study has a low significance due to its retrospective character. But the interest of this study also lies in the follow-up rate obtained. It corresponds to the patient who had a postoperative medical consultation (gastroenterology-nutrition) after a phone call. This rate is higher in older patients who are both more likely to be reachable by telephone (less change of address, less change of mobile phone number) and come more easily to consultation.

Other studies showed a lower follow-up rate at 3 years, follow-up at 6 years is sometimes even lower (27.7%)^13,35–37 (12.34–36). The follow-up rate obtained in our study shows that an active attitude with a telephone call for a consultation allows to obtain an adhesion to an acceptable follow-up. The interest of monitoring support through new technologies (smartphone application) is worth noting, it would improve this surveillance in younger patients.³⁸

In conclusion, the increase in the prevalence of obesity in the elderly population leads to an increase in the demand for bariatric surgery in this age group. SG is a useful and reliable tool in patients who have become aware that a change in lifestyle with a change in eating habits and an increase in physical activity was essential to the long-term good result. Patients over 50 years of age have a good 3-year outcome on weight loss and comorbidities improvement due to the ability to adhere to postoperative follow-up and to change their lifestyle.

Footnotes

Disclosure Statement

No competing financial interests exist.

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