A NARRATIVE REVIEW ON THE CLINICAL PRACTICE GUIDELINES FOR THE MANAGEMENT OF OVERWEIGHT/OBESITY IN ADULTS

Objectives: Obesity causes morbidity and mortality and also impairs the quality of life in humans. Clinical practice guidelines are well established to treat the obese population with or without comorbidities in all the age groups. Obesity in adults is a risk factor for metabolic disorders including Type-2 diabetes mellitus, hypertension, dyslipidemia, etc. Hence, this review has compared the various international clinical practice guidelines for the management of obesity in adults. 
Methods: Four articles were included in the qualitative synthesis after the systematic review of the literature obtained from PubMed/MEDLINE and Web of Sciences. Diagnosis and various interventions including lifestyle, pharmacotherapy and bariatric surgery are compared for the management of obesity in adults. 
Results: The diagnosis is crucial since the criteria to determine overweight/obesity is still under debate due to inconclusive evidence. Various interventions including diet, exercise, behavior, drug therapy, and surgery are being recommended currently for the management of obesity. However, ethnicity and culture play a major role in diagnosis and also interventions. Moreover, personalizing the interventions according to the subject will make sense and offers success in the management of obesity. 
Conclusion: Diagnosis and the intervention should be subject oriented based on ethnicity, culture and patient characteristics. In this connection, many longitudinal studies warranted to specify the diagnostic and management criteria for adults among the various ethnic populations across the world.


Guidelines for the management of overweight and obesity
All the guidelines concerning with the management of overweight/ obesity among the adults and met similar criteria about the BMI classification. The NHMRC [14] and AACE/ACE [11] recommendations based on the BMI (i.e., overweight BMI: 25-29.9; obesity BMI: ≥30); however, weight loss medications (if BMI >27 [11] and/or BMI >28 [14]) and bariatric surgery (if BMI ≥35 [11] and/or BMI >40 [14]) were recommended in addition to the lifestyle changes including diet, physical activity, and behavioral changes (Table 1).
Interestingly, WC is the additional criteria in the European Practical and Patient-Centred Guidelines [12]and NICE [13]. The recommendations have been according to both BMI and WC, however, European Practical and Patient-Centred Guidelines restricted the WC with two categories (i.e., men <94 cm and women <80 cm; men ≥94 cm and women ≥80 cm) [15]. On the other hand, the NICE categorized the WC in three categories (for men, WC of <94 cm is low, 94-102 cm is high, and more than 102 cm is very high; for women, WC of <80 cm is low, 80-88 cm is high, and more than 88 cm is very high). Both recommending diet and physical activity±drugs in obesity Grade II (i.e., BMI >35-39.9) and also diet and physical activity±drugs±surgery for obesity Grade III (i.e., BMI ≥40) Full-text articles excluded (n=5)   (Table 2).

Guidelines for the lifestyle intervention in the management of obesity in adults
The guidelines included in the review generally recommending diet, physical activity, and behavioral change under lifestyle intervention (Table 3).

Diet
Reduction in calorie [13], carbohydrate [11,12], and fat [11] diet generally recommended and encouraged to take more vegetables, fruits, and protein [11,12] and the NHMRC recommends to follow the Australian Dietary Guidelines [16] also substantiates the other guidelines. However, the Mediterranean and Dietary Approaches to Stop Hypertension (DASH) emphasized by the AACE/ACE [11]. Reduction in weight intake/day ranges from 500 to 750 kcal according to the AACE/ACE [11] and 600 according to the NHMRC [14] and NICE guidelines [13].

Physical activity
Aerobic exercise and moderate to greater/vigorous physical activity are recommended for approximately ∼150 min/w in the management of overweight/obesity [11][12][13][14]. In addition, European guidelines recommended physical activity daily [12].

Behavioral change
The recommendation regarding the behavioral change (Table 3) includes the self-monitoring, goal setting, education, problem-solving, stimulus control, behavioral contracting/behavior and progress, stress reduction, psychological support/evaluation, cognitive restructuring, motivational interviewing, mobilization of social support/slowing rate of eating ensuring social support, cognitive behavioral therapy, assertiveness, reinforcement of changes, relapse prevention, and strategies for dealing with weight regain [11][12][13][14].
On the other hand, controversy findings have been reported about the association of cardiometabolic markers with the anthropometric measurements by establishing its association with the WC alone in Canadian adults [35] and both BMI and WC in Chinese adults [36]. However, the criteria to determine the metabolic syndrome by both the International Diabetes Federation [37] and the National Cholesterol Education Program [38] are consistent with both BMI and WC about the anthropometric measurements concerning obesity. In this regard, various research findings were established recently about diet, physical activity, behavioral intervention, and drug therapy.

Diet
The recent studies encourage the intake of Mediterranean diet [39,40] and DASH as part of obesity management [41] dietary approaches to the treatment of obesity [42] and also mindful eating intervention [43] has already been established. Reduction in energy intake/day in kcal is highly encouraged by the clinical practice guidelines for obese adults [11,13,14]. However, the recent guidelines encouraging a very low-calorie diet as a part of a multicomponent weight management strategy, for people who are obese and who have a clinically assessed need to rapidly lose weight [13]. Energy deficit is the primary challenge during this intervention [44] which can be minimized by optimizing the diet according to the individuals [45] with the careful consideration of target risk factors [44]. Moreover, this type of intervention encourages the patient to tailor and personalize their dietary patterns to reduce energy intake for sustainable weight loss [46].
Approximately 150 min/w physical activity is recommended by all the clinical practice guidelines included in this review [11][12][13][14]. The vigorous activity needs 75-150 min/w [14] is recommended to implement gradually with the initial 4-12 w of moderate-intensity activity if an individual with a BMI <35 [52]. Evidence that suggests total daily accumulated energy expenditure is the strongest predictor of weight loss in obesity [53,54]. Cardiorespiratory fitness emphasizing the reduction in the mortality among the obese population with the independent cardiometabolic risk factors including fat deposition [55][56][57], blood pressure [58,59], and glycemic control [59,60]. Various strategies have been explored recently including moderate-to-vigorous-intensity physical activity [61][62][63], comprehensive behavioral intervention including 10,000 steps/d [64], wearable devices in the comprehensive weight loss intervention [65,66], and comprehensive weight loss intervention through a telephone call with a health coach [67,68]. Based on the above findings, the time duration, frequency, and type of exercise need to individualize by considering the BMI/WC and other risk factors in the individual.

Behavioral interventions
Self-monitoring, goal setting, problem-solving, stimulus control, behavioral contracting/behavior and progress, and cognitive restructuring are common behavioral interventions recommended by the clinical practice guidelines (Table 3) [11,13,14]. Behavioral intervention through counseling promotes the dietary habit and physical activity among the adults irrespective of the cardiac risk factors [69][70][71]. However, the most recent randomized controlled trial found no significant changes in BMI using low-intensity weight loss programs and also recommended an incremental dose in the intervention [72]. Digitalbased approach including health behavior change interventions [73] offers specifically the behavior change techniques [74] and modes of delivery may individualize the need for behavioral changes [75,76]. This is further needed to be standardized with the relevant intervention components in promoting chronic weight management [77][78][79].

Drug therapy
Orlistat, lorcaserin, phentermine/topiramate ER, naltrexone/ bupropion, and liraglutide 3 mg are already approved by the FDA [80,81]. Drug therapy in the management of obesity associated with modest weight benefits (5-10% range) with a significant impact on cardiovascular risk [82]. However, drug therapy can be considered as an alternative in such cases neither achieved weight loss with diet and physical activity nor eligible for bariatric surgery. The best approach is to individualizing drugs with specific lifestyle interventions [83] and/or behavioral intervention [82] according to the obese adult. Anti-obesity drugs aimed at limited energy absorption by inhibiting and blocking gastric and pancreatic lipases or amylases, microsomal triglyceride in protein, diacylglycerol-O-acetyltransferase/ monoglycerol-O-acyltransferase, and low-affinity sodium-dependent glucose cotransporter-2 (SGLT2) [84][85][86]. The emerging drugs under investigation including cetilistat (a lipase inhibitor), dapagliflozin (an SGLT2 inhibitor), empagliflozin (an SGLT2 inhibitor), and dirlotapide (an MTP inhibitor) belong to this group appearing as potential drugs by reducing absorption [87].

Surgical intervention
Surgical intervention may be considered if BMI >40 [12][13][14] or ≥35 [11]; however, the criteria are >30 if already made multiple attempts on weight reduction [88]. In addition, BMI >35 associated with the comorbid conditions indicated for bariatric surgery [89]. Significant reduction in mortality from 30% to 50% due to CVD deaths [90] is achieved with the bariatric surgery as compared to lifestyle intervention [91]. However, perioperative mortality (<0.3%) risk is associated with bariatric surgery [92] and the incidence rate is depending on the follow-up, complications, bariatric procedure, individual patient characteristics, etc. [93]. Henceforth, still more research is warranted to examine the long-term outcomes of bariatric surgery in the heterogeneous population [94][95][96][97][98].

CONCLUSION
The selection of anthropometric measurements to determine obesity plays a crucial role initially in the management of obesity since controversy findings reported in this regard. A combination of both the BMI and WC offers additional benefits to classify overweight/obesity; still, ethnicity-based classification is warranted to establish the same. Although obesity has several management options, this should be Orlistat Bupropion/naltrexone Liraglutide Orlistat *Preferred weight loss medication: Individualization therapy, **treating overweight (with comorbidities) and obesity that has been evaluated for long-term safety, ***pharmacotherapy can help patients to maintain compliance, ameliorate obesity-related health risks and improve quality of life, ****anti-obesity drugs are suitable for patients with BMI >30 kg/m 2 or with BMI >27 kg/m 2 with comorbidities. BMI: Body mass index, ER: Extended release