Re: Effects of glucagon-like peptide-1 receptor agonists on weight loss: systematic review and meta-analyses of randomised controlled trials
I query the validity of the declaration that "traditional treatments for obesity are, unfortunately, often short lived and consequently not especially effective¹" when GLP-1R agonists have not yet been proven to be any better. No studies compared the use of GLP-1R agonists to life-style interventions, and furthermore the studies used reported on weight loss for no longer than a year. The drugs considered in this meta-analysis were compared to a control consisting of either no intervention, or diabetic drugs, of which (as is stated) sulphonylureas, insulins and thiazolidinediones are known to increase weight². Exenatide and liraglutide are presented as well-tolerated drugs, but this is based on comparison to other anti-diabetic drugs³, namely sitagliptin, and therefore refers only to patients who are already resigned to the host of side-effects that come with control of their disease. In addition, while perhaps it is presumed obvious, it is never mentioned that exenatide and liraglutide require subcutaneous injection.
It is mentioned that GLP-1R agonists frequently cause nausea, vomiting and diarrhoea; and that these side effects were more common as the dose increased. The efficacy of the drug in regards to weight loss also increased with the dose. It is not much of a leap to assume that some of the weight loss could possibly result from the fact that the subjects receiving the drug felt too ill to continue their normal eating habits, rather than due to the drug's actions on insulin and glucagon. These concerns weaken the paper's evidence suggesting that this treatment be considered a feasible option for weight loss in the general population. There is no doubt that obesity has a significant toll on health, and burden on healthcare, but the search for a quick fix will always have drawbacks.
1 Vilsboll T, Christensen M, Junker AE, Knop F, Gluud LL. Effects of glucagon-like peptide-1 receptor agonists on weight loss: systematic review and meta-analyses of randomised controlled trials. BMJ 2012;344:d7771.
2 Bolen S, Feldman L, Vassy J, Wilson L, Yeh H-C, Marinopoulos S, et al. Systematic review: comparative effectiveness and safety of oral medications for type 2 diabetes mellitus. Ann Intern Med 2007;147:386-99.
3 Davies M, Pratley R, Hammer M, Thomsen AB, Cuddihy R. Liraglutide improves treatment satisfaction in people with type 2 diabetes compared with sitagliptin, each as an add on to metformin. Diabet Med 2011;28:333-7.
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Re: Effects of glucagon-like peptide-1 receptor agonists on weight loss: systematic review and meta-analyses of randomised controlled trials
I query the validity of the declaration that "traditional treatments for obesity are, unfortunately, often short lived and consequently not especially effective¹" when GLP-1R agonists have not yet been proven to be any better. No studies compared the use of GLP-1R agonists to life-style interventions, and furthermore the studies used reported on weight loss for no longer than a year. The drugs considered in this meta-analysis were compared to a control consisting of either no intervention, or diabetic drugs, of which (as is stated) sulphonylureas, insulins and thiazolidinediones are known to increase weight². Exenatide and liraglutide are presented as well-tolerated drugs, but this is based on comparison to other anti-diabetic drugs³, namely sitagliptin, and therefore refers only to patients who are already resigned to the host of side-effects that come with control of their disease. In addition, while perhaps it is presumed obvious, it is never mentioned that exenatide and liraglutide require subcutaneous injection.
It is mentioned that GLP-1R agonists frequently cause nausea, vomiting and diarrhoea; and that these side effects were more common as the dose increased. The efficacy of the drug in regards to weight loss also increased with the dose. It is not much of a leap to assume that some of the weight loss could possibly result from the fact that the subjects receiving the drug felt too ill to continue their normal eating habits, rather than due to the drug's actions on insulin and glucagon. These concerns weaken the paper's evidence suggesting that this treatment be considered a feasible option for weight loss in the general population. There is no doubt that obesity has a significant toll on health, and burden on healthcare, but the search for a quick fix will always have drawbacks.
1 Vilsboll T, Christensen M, Junker AE, Knop F, Gluud LL. Effects of glucagon-like peptide-1 receptor agonists on weight loss: systematic review and meta-analyses of randomised controlled trials. BMJ 2012;344:d7771.
2 Bolen S, Feldman L, Vassy J, Wilson L, Yeh H-C, Marinopoulos S, et al. Systematic review: comparative effectiveness and safety of oral medications for type 2 diabetes mellitus. Ann Intern Med 2007;147:386-99.
3 Davies M, Pratley R, Hammer M, Thomsen AB, Cuddihy R. Liraglutide improves treatment satisfaction in people with type 2 diabetes compared with sitagliptin, each as an add on to metformin. Diabet Med 2011;28:333-7.
Competing interests: No competing interests