Document Detail

Effects of exenatide and liraglutide on heart rate, blood pressure and body weight: systematic review and meta-analysis.
Jump to Full Text
MedLine Citation:
PMID:  23355666     Owner:  NLM     Status:  PubMed-not-MEDLINE    
OBJECTIVES: To synthesise current evidence for the effects of exenatide and liraglutide on heart rate, blood pressure and body weight.
DESIGN: Meta-analysis of available data from randomised controlled trials comparing Glucagon-like peptide-1 (GLP-1) analogues with placebo, active antidiabetic drug therapy or lifestyle intervention.
PARTICIPANTS: Patients with type 2 diabetes.
OUTCOME MEASURES: Weighted mean differences between trial arms for changes in heart rate, blood pressure and body weight, after a minimum of 12-week follow-up.
RESULTS: 32 trials were included. Overall, GLP-1 agonists increased the heart rate by 1.86 beats/min (bpm) (95% CI 0.85 to 2.87) versus placebo and 1.90 bpm (1.30 to 2.50) versus active control. This effect was more evident for liraglutide and exenatide long-acting release than for exenatide twice daily. GLP-1 agonists decreased systolic blood pressure by -1.79 mm Hg (-2.94 to -0.64) and -2.39 mm Hg (-3.35 to -1.42) compared to placebo and active control, respectively. Reduction in diastolic blood pressure failed to reach statistical significance (-0.54 mm Hg (-1.15 to 0.07) vs placebo and -0.50 mm Hg (-1.24 to 0.24) vs active control). Body weight decreased by -3.31 kg (-4.05 to -2.57) compared to active control, but by only -1.22 kg (-1.51 to -0.93) compared to placebo.
CONCLUSIONS: GLP-1 analogues are associated with a small increase in heart rate and modest reductions in body weight and blood pressure. Mechanisms underlying the rise in heart rate require further investigation.
Louise E Robinson; Tim A Holt; Karen Rees; Harpal S Randeva; Joseph P O'Hare
Related Documents :
24773956 - Atrial septal defect with severe pulmonary hypertension in elderly patients: usefulness...
24220586 - Genetics of diastolic heart failure.
24477046 - Impact of castration on changes in left ventricular diastolic pressure-volume relations...
2590916 - Compilation of regression equations employing the rr interval for the correction of sys...
7113766 - A bartter-like syndrome after jejunoileal bypass for obesity.
3386296 - Real-time measurement of tricuspid valve annular area for annuloplasty. experimental st...
Publication Detail:
Type:  Journal Article     Date:  2013-01-24
Journal Detail:
Title:  BMJ open     Volume:  3     ISSN:  2044-6055     ISO Abbreviation:  BMJ Open     Publication Date:  2013  
Date Detail:
Created Date:  2013-01-28     Completed Date:  2013-01-29     Revised Date:  2013-11-25    
Medline Journal Info:
Nlm Unique ID:  101552874     Medline TA:  BMJ Open     Country:  England    
Other Details:
Languages:  eng     Pagination:  -     Citation Subset:  -    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Full Text
Journal Information
Journal ID (nlm-ta): BMJ Open
Journal ID (iso-abbrev): BMJ Open
Journal ID (hwp): bmjopen
Journal ID (publisher-id): bmjopen
ISSN: 2044-6055
Publisher: BMJ Publishing Group, BMA House, Tavistock Square, London, WC1H 9JR
Article Information
Download PDF
Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to
Received Day: 28 Month: 8 Year: 2012
Revision Received Day: 15 Month: 11 Year: 2012
Accepted Day: 3 Month: 12 Year: 2012
collection publication date: Year: 2013
Electronic publication date: Day: 24 Month: 1 Year: 2013
Volume: 3 Issue: 1
E-location ID: e001986
PubMed Id: 23355666
ID: 3563145
Publisher Id: bmjopen-2012-001986
DOI: 10.1136/bmjopen-2012-001986

Effects of exenatide and liraglutide on heart rate, blood pressure and body weight: systematic review and meta-analysis Alternate Title:Meta-analysis of effects of GLP-1 on heart rate, blood pressure and body weight
Louise E Robinson1
Tim A Holt12
Karen Rees1
Harpal S Randeva1
Joseph P O'Hare1
1Warwick Medical School, University of Warwick, Coventry, UK
2Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
Correspondence to Dr Tim A Holt;

Article summary
Article focus
  • Glucagon-like peptide-1 (GLP-1) agonists are increasingly used in the management of type 2 diabetes, but their long-term cardiovascular safety is not yet confirmed.
  • These agents are known to reduce body weight and blood pressure, but are also associated with an elevation in heart rate that has not previously been quantified.
Key messages
  • Our analysis confirms the weight and blood pressure reducing effects of liraglutide and exenatide, and reports a small rise in heart rate.
  • The weight-reducing effects are substantially greater when compared with active control treatments than placebo, as alternative treatment options may promote weight gain.
  • Heart rate rises were more evident for liraglutide than exenatide, and for exenatide long-acting release than exenatide twice daily.
Strengths and limitations
  • We included unpublished data obtained from pharmaceutical companies, enabling the effects of GLP-1 agonists on heart rate to be quantified for the first time by meta-analysis.
  • Our analysis is limited by significant heterogeneity between studies, and suggests the need for more detailed investigation using more accurate measurements of heart rate than those typically used in clinical practice.


In contrast to the weight-increasing effects of several traditional antidiabetic drug classes,1 Glucagon-like peptide-1 (GLP-1) analogues have been shown to reduce both body weight and blood pressure.2 The mechanisms producing weight loss have been extensively investigated and involve improved satiety and reduced calorie ingestion, both through effects on the central nervous system and through delayed gastric emptying.3–6 Those leading to reduced blood pressure are less adequately understood, but this effect has been shown to occur as early as 2 weeks after the start of the therapy, preceding significant weight loss, suggesting that a direct hypotensive effect is at least partly responsible.7 Experimental studies of GLP-1 analogues have also reported direct effects on blood pressure, possibly via interaction with the autonomic nervous system.8, 9

While a number of studies have reported heart rate increases, the associated mechanisms are unknown, and this effect is often dismissed as clinically unimportant. Given the safety implications attributed to raised heart rate in other contexts,10–13 there is a surprising lack of concern over its possible implications in this setting. A recent review of liraglutide by Bode acknowledges the effect,14 but a meta-analysis on the safety of incretin-based therapies published in 2010 did not mention heart rate,15 and neither did an overview of the LEAD trials of liraglutide by Blonde and Russell-Jones.16 A large nationwide audit of exenatide designed by the Association of British Clinical Diabetologists (ABCD) did not include heart rate as an outcome, despite citing evidence for the effect in the main published report.17 A subsequent (ongoing) ABCD audit of liraglutide also aims to identify unknown safety issues but has similarly omitted heart rate from the protocol.18

GLP-1 analogues are an expanding drug class with the recent development of longer acting agents including the once weekly (LAR) form of exenatide, Bydureon. This drug has recently obtained approval from the National Institute for Health and Clinical Excellence for use in type 2 diabetes, and its use is likely to increase.19 A review of trial data from five long-acting GLP-1 agonists (exenatide once weekly, taspoglutide, albiglutide, LY2189265 and CJC-1134-PC) concluded that they were more likely than shorter acting formulations to raise the heart rate.20 A more recently published study of the long-acting GLP-1 agent PF-04603629 reported a substantial rise in the heart rate (a mean increase of 23 bpm at 24 h after injection of the higher dose studied), together with a rise in the diastolic blood pressure.21

While there is no evidence to date that these agents (short-acting or long-acting) increase cardiovascular event rates, safety data are limited by short follow-up duration.22 A longer term follow-up is underway but will take a number of years to complete.

We aimed to identify and synthesise all available heart rate data from both published and unpublished sources to quantify the effect of GLP-1 analogues on heart rate, as well as that on blood pressure and body weight.

Literature searches

The following resources were systematically searched to identify completed, new or ongoing controlled trials of liraglutide or exenatide: Clinical Trials Gov (;;; Centerwatch; Drugsontrial; WebMD; MEDLINE (from 1960); EMBASE (from 1960); Cochrane Library Central Register of Controlled Trials (CENTRAL). We used a search strategy to capture ‘exenatide’, ‘liraglutide’ or ‘glucagon-like peptide-1’ in any field, limited to ‘Randomised Controlled Trial’, ‘Clinical Trial’ or ‘Controlled Clinical Trial’. Conference proceedings (British Endocrinology Society, Diabetes UK, European Association for the Study of Diabetes) and websites (American Diabetes Association, Federal Drug Agency and European Medicines Agency) were examined, and the reference lists of trials, meta-analyses and reviews were searched for further studies. Novo Nordisk and Amylin Pharmaceuticals were contacted directly to request unpublished data. The review is up to date at July 2012.

Inclusion and exclusion criteria
  1. Participants: We only included trials involving participants with type 2 diabetes.
  2. Study designs: We included all randomised trials with a minimum follow-up of 12 weeks. We excluded ‘open-label’ extension studies of phase 3 trials.
  3. Interventions: Trials of liraglutide (1.2 or 1.8 mg daily), exenatide (5 or 10 µg twice daily) or exenatide LAR, either alone or in combination with an oral anti-diabetic drug (OAD) or insulin, were included. These doses were chosen to coincide with those most commonly used in clinical practice.
  4. Comparison groups(s): Comparators included placebo, OAD, lifestyle intervention or insulin.
  5. Outcomes: We included all studies reporting heart rate, blood pressure or body weight outcomes.
Data extraction

Retrieved studies were assessed for inclusion by two researchers independently using the above criteria, and any discrepancies were resolved by consensus. Information on the participants, intervention, comparison group, outcomes and trial quality was extracted from included studies by two researchers independently. Where necessary, clarification of data was obtained by correspondence with trial co-ordinators.

Risk of bias

We used the Cochrane tool to determine risk of selection bias (success of sequence generation and allocation concealment); performance bias (success of blinding to treatment received); detection bias (blinding of outcome assessment), attrition bias (incomplete outcome data and selective outcome reporting) and other biases.23 Funnel plots were used to detect publication bias.


Means and SDs for baseline and outcome values for blood pressure, heart rate and body weight were extracted. Mean effect data from crossover trials were extracted at the end of the initial phase. Where SDs for the outcome were not available, they were imputed according to the Cochrane Handbook for Systematic reviews V.5.23 SDs for changes from baseline were derived where necessary to account for correlation of baseline to follow-up measurements within individuals, and where the correlation coefficient could not be calculated, methods were employed as recommended by Follman et al.24 Study results were combined using RevMan V.5.2. Heterogeneity was estimated using the χ2 test and I2 statistic. Fixed and random effects weighted mean difference models using the Inverse Variance technique were used to compare outcomes between the study drug and comparator with 95% CI. Interaction effects were evaluated using prespecified subgroup analyses (comparing various doses of the study drug to active control or placebo) and type of GLP-1 agonist (liraglutide, exenatide twice daily and exenatide LAR preparations). Results are described using the random effects approach due to the heterogeneity of the included studies. Analyses were stratified by active control or placebo. We compared heterogeneity measures between these subgroups and according to the GLP-1 agent. We also undertook sensitivity analyses to investigate the influence of trial designs on heterogeneity measures, including the background OAD treatment common to both arms. Funnel plots were assessed for asymmetry.


Figure 1 describes the identification of the studies included. A total of 521 articles were screened. Of these, 472 were excluded on the basis of the title or abstract being irrelevant to the aims of this review. Forty-nine studies were examined in full text. Of these, four were excluded because the comparator was another form of GLP-1.25–28 In three cases, the doses were not as specified in our inclusion criteria,29–31 and in a further two, the study involved further analysis of data from trials that were already included.32, 33 Finally, eight were open label extension studies.34–41 This left 32 trials included in our review (figure 1 and table 1).42–73 Most studies did not report all of the outcomes of interest, or they did not provide them as usable numerical data. Data were therefore obtained, where available, directly from the pharmaceutical companies.

Methodological quality and risk of bias

Results of risk of bias assessment are given in table 2. Explanation of sequence generation and allocation concealment was adequate for all trials. In nine trials, at least one arm was open label. Attrition was adequately described and was greater than 20% in nine studies. The proportion of the intention-to-treat population completing the study varied in range 65.4–99.6% and had a median of 83.7%. None of the trials were terminated prematurely. Funnel plots were broadly symmetrical with no evidence of publication bias.


The trials varied in terms of duration of follow-up, location, type of active comparator drug and background therapy. One study was a crossover trial43 and another was of a prolonged follow-up.55 The mean age of the participants ranged from 52.3 to 60.3 years. For most outcomes, we found significant heterogeneity (figures 2BMJOPEN2012001986F3BMJOPEN2012001986F4BMJOPEN2012001986F56). We, therefore, chose to report results using the random effects approach, although the differences between random effects and fixed effect results were very small. Heterogeneity varied significantly between comparisons. For the effect of liraglutide on heart rate compared with placebo, the I2 value was 55%. However, this value reduced to 0% when the data from a single trial (LEAD-1) were withheld.

Heart rate

A total of 22 studies provided heart rate data. Overall, GLP-1 agonists produce a significant increase in heart rate with a weighted mean difference of 1.86 bpm (0.85 to 2.87) versus placebo and 1.90 bpm (1.30 to 2.50) versus active control. Looking at specific agents, liraglutide increases heart rate by 2.71 bpm (1.45 to 3.97) versus placebo and 2.49 (1.77 to 3.21) versus active control. Data from the LEAD trials of liraglutide57, 64, 67, 69, 73 were initially grouped into quartiles of baseline heart rate and demonstrated significant variations in effect between these subgroups, with the greatest increase seen in those with the lowest baseline values. Exenatide twice daily increased the heart rate by 0.82 bpm (−0.15 to 1.79) versus active control and by 0.88 bpm (−0.47 to 2.22) versus placebo, which did not reach statistical significance (figure 3). Exenatide LAR produced a more significant change (2.14 bpm (1.11 to 3.17) versus active control), but the number of studies involving this formulation was small.

Blood pressure

We included 31 trials measuring blood pressure changes (figures 4 and 5). GLP-1 agonists reduced systolic blood pressure by −1.79 mm Hg (−2.94 to −0.64) compared to placebo and by −2.39 (−3.35 to −1.42) compared to active control. Reductions in diastolic blood pressure failed to reach statistical significance and were −0.54 mm Hg (−1.15 to 0.07) compared to placebo and −0.50 mm Hg (−1.24 to 0.24) compared to active control.

Body weight

Twenty-one trials measuring changes in weight were included (figure 6). We confirm a small but highly significant reduction in body weight as a result of GLP-1 therapy. Weight changed by −3.31 kg (−4.05 to −2.57) compared to active control but by only −1.22 kg (−1.51 to −0.93) compared to placebo.


We have confirmed and quantified the effects of liragutide and exenatide on heart rate, blood pressure and body weight. Our analysis benefited from the inclusion of unpublished data supplied by Novo Nordisk and Amylin Pharmaceuticals, as these were often missing from published trial reports. It was limited by the significant heterogeneity of effect size measurements between individual studies. We examined prespecified subgroups according to the GLP-1 agent and type of comparator (placebo or active control). Active control treatments varied between trials and included different classes of OAD and insulins, which may explain some of the variation in measured effect. Other potential sources of heterogeneity include the characteristics of background OAD treatments common to both arms as these treatments differed between trials. For the heart rate effect of liraglutide versus placebo, the heterogeneity was largely attributable to a single trial (LEAD-1), but the cause of the higher heart rate effect in this trial is unclear.

The weight-reducing effects of these agents are a welcome contrast to the weight-promoting effects of other treatment options, including sulphonylureas, thiazolidinediones and insulin. We have derived a similar effect size to a previously reported value for weight loss,2 although our study has distinguished between placebo and active comparators, in which effects sizes differ substantially. Together with the reduction in blood pressure, this may improve longer term cardiovascular risk. However, the small rise in heart rate is a reason for caution, as it might potentially be associated with adverse outcomes. This rise was more evident for liraglutide than exenatide twice daily, but exenatide LAR may produce a greater response than the twice-daily formulation. The clinical significance of this heart rate rise is still unknown from the perspective of cardiovascular risk.

For most GLP-1 trials, heart rate is a secondary outcome measured as part of safety assessment, and is reported inconsistently. In clinic, it is often measured using a very short sampling interval (perhaps 1 min of data). One study was designed specifically to examine the effects of exenatide twice daily on change in heart rate as the primary outcome using 24 h ambulatory monitoring.58 The mean change from baseline at 12 weeks was 2.1 bpm for exenatide twice daily and −0.7 bpm for placebo. The sample size (54 randomised participants) in this pilot study was relatively small and the difference was not significant (p=0.16), but it is similar to the values we have obtained generally for GLP-1 agonists in our meta-analysis. Measurement of heart rate using this 24 h technique (compared with a traditional heart rate measurement in clinic) substantially improves the accuracy of measurement as heart rate is very variable within the individual. This technique could be used as a basis for a larger study powered to detect such a difference and to investigate the influence of alternative background medications.

This review highlights the need to improve our understanding of the physiological mechanisms through which GLP-1 agonists act, while the results of longer term safety studies are awaited. Both autonomic nervous system-dependent and system-independent effects have been suggested in animal studies as a basis for the rise in heart rate.74, 75 The heart rate response in the presence or absence of autonomic neuropathy in human patients might therefore justify further study. There is also a clear need to improve the comprehensive reporting of all outcome data measured during clinical trials of antidiabetic agents, particularly those relevant to cardiovascular risk.

Supplementary Material Author's manuscript
Reviewer comments


Contributors: LER, JPO and HSR were involved in the design and conception of the study. LER and TAH conducted the bibliographic searches, identified the included papers and extracted the data independently. KR advised on methodological issues. All authors were involved in the drafting of the manuscript.

Funding: This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

Competing interests: LER, TAH and KR have no interests to declare. JPO and HSR have received research funding (paid to Warwick Medical School) from Novo Nordisk, and payments for speaking from Novo Nordisk.

Data sharing statement: All data used in this study are freely available by request to the corresponding author TAH.

We would like to thank Amylin Pharmaceuticals and Novo Nordisk for providing us with unpublished data for this meta-analysis.

1. Nathan DM,Buse JB,Davidson MB,et al. Medical management of hyperglycemia in type 2 diabetes: a consensus algorithm for the initiation and adjustment of therapy. Diabetes CareYear: 2009;32:193–20318945920
2. Vilsboll T,Christensen M,Junker AE,et al. Effects of glucagon-like peptide receptor agonists on weight loss: systematic review and meta-analyses of randomized controlled trials. BMJYear: 2012;344:1–11
3. Flint A,Raben A,Astrup A,et al. Glucagon-like peptide 1 promotes satiety and suppresses energy intake in humans. J Clin InvestYear: 1998;101:515–209449682
4. MacDonald PE,El-kholy W,Riedel MJ,et al. The multiple actions of GLP-1 on the process of glucose-stimulated insulin secretion. DiabetesYear: 2002;51(Suppl 3):S434–4212475787
5. Willms B,Werner J,Holst JJ,et al. Gastric emptying, glucose responses, and insulin secretion after a liquid test meal: effects of exogenous glucagon-like peptide-1 (GLP-1)-(7-36) amide in type 2 (noninsulin-dependent) diabetic patients. J Clin Endocrinol MetabYear: 1996;81:327–328550773
6. Meier JJ,Nauck MA. Glucagon-like peptide 1(GLP-1) in biology and pathology. Diabetes Metab Res RevYear: 2005;21:91–11715759282
7. Varanasi A,Chaudhuri A,Dhindsa S,et al. Durability of effects of exenatide on glycaemic control, body weight, systolic blood pressure, C-reactive protein and triglyceride concentrations. Endocrin PracYear: 2011;17:192–200
8. Bojanowska E,Stempniak B. Effects of glucagon-like peptide-1 (7-36) amide on neurohypophysial hormone secretion induced by acute hyperosmotic challenge. NeuropeptidesYear: 2003;37:45–5012637035
9. Bharucha AE,Charkoudian N,Andrews CN,et al. Effects of glucagon-like peptide-1, yohimbine, and nitrergic modulation on sympathetic and parasympathetic activity in humans. Am J Physiol Regul Integr Comp PhysiolYear: 2008;295:R874–8018596108
10. Levine HJ. Rest heart rate and life expectancy. J Am Coll CardiolYear: 1997;30:1104–69316546
11. Aronow WS,Ahn C,Mercando AD,et al. Association of average heart rate on 24-hour ambulatory electrocardiograms with incidence of new coronary events at 48-month follow-up in 1311 patients (mean age 81 years) with heart disease and sinus rhythm. Am J CardiolYear: 1996;78:1175–68914888
12. Hozawa A,Ohkubo T,Kikuya M,et al. Prognostic value of home heart rate for cardiovascular mortality in the general population: the Ohasama study. Am J HypertensYear: 2004;17:1005–1015533725
13. Anselmino M,Öhrvik J,Rydén L. Resting heart rate in patients with stable coronary artery disease and diabetes: a report from the euro heart survey on diabetes and the heart. Eur Heart JYear: 2010;31:3040–520935002
14. Bode B. An overview of the pharmacokinetics, efficacy and safety of liraglutide. Diab Res Clin PractYear: 2012;97:27–42
15. Fakhoury WKH,Lereun C,Wright D. A meta-analysis of placebo-controlled clinical trials assessing the efficacy and safety of incretin-based medications in patients with type 2 diabetes. PharmacolYear: 2010;86:44–57
16. Blonde L,Russell-Jones D. The safety and efficacy of liraglutide with or without oral antidiabetic drug therapy in type 2 diabetes: an overview of the LEAD 1–5 studies. Diabetes Obes MetabYear: 2009;11(Suppl 3):26–3419878259
17. Ryder REJ,Thong KY,Cull ML,et al. on behalf of the ABCD nationwide exenatide audit contributorsThe Association of British Clinical Diabetologists (ABCD) nationwide exenatide audit. Practical Diabetes IntYear: 2010;27:352–7
18. (accessed 18 Apr 2012. ).
19. National Institute for Health and Clinical ExcellenceTechnology Appraisal TA248. Exenatide prolonged-release suspension for injection in combination with oral antidiabetic therapy for the treatment of type 2 diabetes. London: NICE, Year: 2012
20. Madsbad S,Kielgast U,Asmar M,et al. An overview of once-weekly glucagon-like peptide-1 receptor agonists—available efficacy and safety data and perspectives for the future. Diabetes Obes MetabYear: 2011;13:394–40721208359
21. Gustavson SM,Chen D,Somayaji V,et al. Effects of a long-acting GLP-1 mimetic (PF-04603629) on pulse rate and diastolic blood pressure in patients with type 2 diabetes mellitus. Diabetes Obes MetabYear: 2011;13:1056–821812891
22. Ratner R,Han J,Nicewarner D,et al. Cardiovascular safety of exenatide BID: an integrated analysis from controlled clinical trials in participants with type 2 diabetes. Cardiovasc DiabetolYear: 2011;10:22–3221410975
23. Higgins JPT,Green S. Cochrane handbook for systematic reviews of interventions. Version 5.1.0 (updated March 2011). The Cochrane Collaboration, Year: 2011 (accessed 15 Nov 2012)..
24. Follman D,Elliott P,Suh I,et al. Variance imputation for overviews of clinical trials with continuous response. J Clin EpidemiolYear: 1992;45:769–731619456
25. Blevins T,Pullman J,Malloy J,et al. DURATION 5: exenatide once weekly resulted in greater improvements in glycemic control compared with exenatide twice daily in patients with type 2 diabetes. J Clin Endocrinol MetabYear: 2011;96:1301–1021307137
26. Buse JB,Rosenstock J,Sesti G,et al. Liraglutide once a day versus exenatide twice a day for type 2 diabetes: a 26-week randomised, parallel-group, multinational, open label trial (LEAD-6). LancetYear: 2009;374:39–4719515413
27. Buse JB,Drucker DJ,Taylor KL,et al. DURATION-1: exenatide once weekly produces sustained glycemic control and weight loss over 52 weeks. Diabetes CareYear: 2010;33:1255–6120215461
28. Drucker D,Buse JB,Taylor K,et al. Exenatide once-weekly versus twice daily for the treatment of type 2 diabetes: a randomized open-label, non-inferiority study. LancetYear: 2008;372:1240–5018782641
29. Bunck MC,Diamant M,Corner A,et al. One-year treatment with exenatide improves beta-cell function, compared with insulin glargine, in metformin-treated type 2 diabetic patients: a randomized, controlled trial. Diabetes CareYear: 2009;32:762–819196887
30. Feinglos MN,Saad MF,Pi-Sunyer FX,et al. Effects of liraglutide (NN2211), a long-acting GLP-1 analogue, on glycaemic control and bodyweight in subjects with Type 2 diabetes. Diabet MedYear: 2005;22:1016–2316026367
31. Vilsboll T,Zdravkovic M,Le-Thi T,et al. Liraglutide, a long-acting human glucagon-like peptide-1 analog, given as monotherapy significantly improves glycemic control and lowers body weight without risk of hypoglycemia in patients with type 2 diabetes. Diabetes CareYear: 2007;30:1608–1017372153
32. Bode BW,Testa MA,Magwire M,et al. Patient-reported outcomes following treatment with the human GLP-1 analogue liraglutide or glimepiride in monotherapy: results from a randomized controlled trial in patients with type 2 diabetes. Diabetes Obes MetabYear: 2010;12:604–1220590735
33. Davies M,Pratley R,Hammer M,et al. Liraglutide improves treatment satisfaction in people with type 2 diabetes compared with sitagliptin, each as an add on to metformin. Diabet MedYear: 2011;28:333–721309842
34. Bunck MC,Cornér A,Eliasson B,et al. One year treatment with exenatide vs. insulin glargine: effects on post-prandial glycemia, lipid profiles and oxidative stress. AtherosclerosisYear: 2010;212:223–920494360
35. Bunck MC,Cornér A,Eliasson B,et al. Effects of exenatide on measures of beta-cell function after 3 years in metformin-treated patients with type 2 diabetes. Diabetes CareYear: 2011;34:2041–721868779
36. Buse JB,Klonoff DC,Nielsen LL,et al. Metabolic effects of two years of exenatide treatment on diabetes, obesity, and hepatic biomarkers in patients with type 2 diabetes: an interim analysis of data from the open-label, uncontrolled extension of three double-blind, placebo-controlled trials. Clin TherYear: 2007;29:139–5317379054
37. Klonoff DC,Buse JB,Nielsen LL,et al. Exenatide effects on diabetes, obesity, cardiovascular risk factors and hepatic biomarkers in patients with type 2 diabetes treated for at least 3 years. Curr Med Res OpinYear: 2008;24:275–8618053320
38. Pratley R,Nauck M,Bailey T,et al. One year of liraglutide treatment offers sustained and more effective glycaemic control and weight reduction compared with sitagliptin, both in combination with metformin, in patients with type 2 diabetes: a randomised, parallel-group, open-label trial. Int J Clin PractYear: 2011;65:397–40721355967
39. Ratner RE,Maggs D,Nielsen LL. et al. Long term effects of exenatide therapy over 82 weeks on glycemic control and weight in overweight metformin treated patients with type 2 diabetes mellitus. Diabetes Obes MetabYear: 2006;8:419–2816776749
40. Riddle MC,Henry RR,Poon TH,et al. Exenatide elicits sustained glycaemic control and progressive reduction of body weight in patients with type 2 diabetes inadequately controlled by sulphonylureas with or without metformin. Diabetes Metab Res RevYear: 2006;22:483–9116634116
41. Wysham C,Bergenstal R,Malloy J,et al. DURATION-2: efficacy and safety of switching from maximum daily sitagliptin or pioglitazone to once-weekly exenatide. Diabet MedYear: 2011;28:705–1421434995
42. Apovian CM,Bergenstal RM,Cuddihy RM,et al. Effects of exenatide combined with lifestyle modification in patients with type 2 diabetes. Am J MedYear: 2010;123:468–7720399326
43. Barnett AH,Burger J,Johns D,et al. Tolerability and efficacy of exenatide and titrated insulin glargine in adult patients with type 2 diabetes previously uncontrolled with metformin or a sulphonylurea: a multinational, randomised, open label two period crossover non-inferiority trial. Clin TherYear: 2007;29:2333–4818158075
44. Bergenstal R,Lewin A,Bailey T,et al. Efficacy and safety of biphasic insulin aspart 70/30 versus exenatide in subjects with type 2 diabetes failing to achieve glycemic control with metformin and a sulfonylurea. Curr Med Res OpinYear: 2009;25:65–7519210140
45. Bergenstal RM,Wysham C,MacConell L,et al. Efficacy and safety of exenatide once weekly versus sitagliptin or pioglitazone as an adjunct to metformin for treatment of type 2 diabetes (DURATION-2): a randomised trial. LancetYear: 2010;376:431–920580422
46. Buse JB,Henry RR,Han J,et al. Effects of exenatide (exendin-4) on glycaemic control over 30 weeks in patients with type 2 diabetes treated with metformin and a sulphonylurea. Diabetes CareYear: 2004;27:2628–3515504997
47. Buse JB,Bergenstal RM,Glass LC,et al. Use of twice daily exenatide in basal insulin-treated patients with type 2 diabetes. A randomized controlled trial. Ann Int MedYear: 2011;154:103–1221138825
48. Davies MJ,Donnelly R,Barnett AH,et al. Exenatide compared with long-acting insulin to achieve glycaemic control with minimal weight gain in patients with type 2 diabetes: results of helping evaluate exenatide in patients with diabetes compared with long-acting insulin (HEELA) study. Diabetes Obes MetabYear: 2009;11:1153–6419930005
49. DeFronzo RA,Ratner RE,Han J,et al. Effects of exenatide (exendin-4) on glycemic control and weight over 30 weeks in metformin-treated patients with type 2 diabetes. Diabetes CareYear: 2005;28:1092–10015855572
50. Defronzo RA,Triplitt C,Qu Y,et al. Effects of exenatide plus rosiglitazone on beta-cell function and insulin sensitivity in subjects with type 2 diabetes on metformin. Diabetes CareYear: 2010;33:951–720107105
51. Derosa G,Maffioli P,Salvadeo SA,et al. Exenatide vs. glibenclamide in patients with diabetes. Diabetes Technol TherapYear: 2010;12:233–4020151774
52. Derosa G,Putignano P,Bossi AC,et al. Exenatide or glimepiride added to metformin on metabolic control and on insulin resistance in type 2 diabetic patients. Eur J PharmacolYear: 2011;666:251–621645507
53. Diamant M,Gaal L,Stranks S,et al. Once weekly exenatide compared with insulin glargine titrated to target in patients with type 2 diabetes (DURATION 3): An open-label randomised trial. LancetYear: 2010;375:2234–4320609969
54. Gallwitz B,Bohmer M,Segiet T,et al. Exenatide twice daily versus premixed insulin aspart 70/30 in metformin-treated patients with type 2 diabetes: a randomized 26-week study on glycemic control and hypoglycaemia. Diabetes CareYear: 2011;34:604–621285388
55. Gallwitz B,Guzman J,Dotta F,et al. Exenatide twice daily versus glimepiride for prevention of glycaemic deterioration in patients with type 2 diabetes with metformin failure (EUREXA): an open-label, randomised controlled trial. LancetYear: 2012;379:2270–822683137
56. Gao Y,Yoon KH,Chuang L-M,et al. Efficacy and safety of exenatide in patients of Asian descent with type 2 diabetes inadequately controlled with metformin or metformin and a sulphonylurea. Diabetes Res Clin PractYear: 2009;83:69–7619019476
57. Garber A,Henry R,Ratner R,et al. , for the LEAD-3 (Mono) Study GroupLiraglutide versus glimepiride monotherapy for type 2 diabetes (LEAD-3 Mono): a randomised, 52-week, phase III, double-blind, parallel-treatment trial. LancetYear: 2009;373:473–8118819705
58. Gill A,Hoogwerf BJ,Burger J,et al. Effect of exenatide on heart rate and blood pressure in subjects with type 2 diabetes mellitus: a double blind, placebo controlled, randomized pilot study. Cardiovasc DiabetolYear: 2010;9:620109208
59. Heine RJ,Van Gaal LF,Johns D,et al. , GWAA Study GroupExenatide vs insulin glargine in patients with suboptimally controlled type 2 diabetes: a randomised trial. Ann Intern MedYear: 2005;143:559–6916230722
60. Kadowaki T,Namba M,Yamamura A,et al. Exenatide exhibits dose-dependent effects on glycemic control over 12 weeks in Japanese patients with suboptimally controlled type 2 diabetes. Endocr JYear: 2009;56:415–2419194050
61. Kendall DM,Riddle MC,Rosenstock J,et al. Effects of exenatide (Exendin-4) on glycaemic control over 30 weeks in patients with type 2 diabetes treated with metformin and a sulphonylurea. Diabetes CareYear: 2005;28:1083–9115855571
62. Kim D,MacConell L,Zhuang D,et al. Effects of once-weekly dosing of a long-acting release formulation of exenatide on glucose control and body weight in subjects with type 2 diabetes. Diabetes CareYear: 2007;30:1487–9317353504
63. Liutkus J,Guzman JR,Norwood P,et al. A placebo-controlled trial of exenatide twice-daily added to thiazolidinediones alone or in combination with metformin. Diabetes Obes MetabYear: 2010;12:1058–6520977576
64. Marre M,Shaw J,Brandle M,et al. Liraglutide once-daily human GLP-1 analogue, added to a sulphonylurea over 26 weeks produces greater improvements in glycaemic and weight control compared with adding rosiglitazone or placebo in subjects with type 2 diabetes (Lead 1-SU). Diabet MedYear: 2009;26:268–7819317822
65. Moretto TJ,Milton DR,Ridge TD. et al. Efficacy and tolerability of exenatide monotherapy over 24 weeks in antidiabetic drug-naive patients with type 2 diabetes: a randomized, double blind, placebo-controlled parallel-group study. Clin TherYear: 2008;30:1448–6018803987
66. Nauck MA,Duran S,Kim D,et al. A comparison of twice-daily exenatide and biphasic insulin aspart in patients with type 2 diabetes who were suboptimally controlled with sulfonylurea and metformin: a non-inferiority study. DiabetologiaYear: 2007;50:259–6717160407
67. Nauck M,Frid A,Hermansen K,et al. Efficacy and safety comparison of liraglutide, glimepiride and placebo, all in combination with metformin in type 2 diabetes. Diabetes CareYear: 2009;32:84–9018931095
68. Pratley RE,Nauck M,Bailey T,et al. Liraglutide vs sitagliptin for patients with type 2 diabetes who did not have adequate glycemic control with metformin: a 26 week, randomised, parallel group, open-label trial. LancetYear: 2010;375:1447–5620417856
69. Russell-Jones D,Vaag A,Schmitz O,et al. Liraglutide vs insulin glargine and placebo in combination with metformin and sulfonylurea therapy in type 2 diabetes mellitus (LEAD-5 met+SU): a randomised controlled trial. DiabetologiaYear: 2009;52:2046–5519688338
70. Russell-Jones D,Cuddihy RM,Hanefeld M,et al. Efficacy and safety of exenatide once weekly versus metformin, pioglitazone, and sitagliptin used as monotherapy in drug-naïve patients with type 2 diabetes (DURATION-4): a 26-week double-blind study. Diabetes CareYear: 2012;35:252–822210563
71. Yang W,Chen L,Ji Q,et al. Liraglutide provides similar glycaemic control as glimepiride (both in combination with metformin) and reduces body weight and systolic blood pressure in Asian population with type 2 diabetes from China, South Korea and India: a 16-week, randomized, double-blind, active control trial. Diabetes Obes MetabYear: 2011;13:81–821114607
72. Zinman B,Hoogerworf BJ,Garcia SD,et al. The effect of adding exenatide to a thiazolidinedione in sub-optimally controlled type 2 diabetes. A randomized trial. Ann Intern MedYear: 2007;146:477–8517404349
73. Zinman B,Gerich J,Buse J,et al. Efficacy and safety of the human glucagon-like peptide-1 analog liraglutide in combination with metformin and thiazolidinedione in patients with type 2 diabetes (LEAD-4 Met+TZD). Diabetes CareYear: 2009;32:1224–3019289857
74. Gardiner SM,March JE,Kemp PA,et al. Autonomic nervous system-dependent and—independent cardiovascular effects of exendin-4 infusion in conscious rats. Br J PharmacolYear: 2008;154:60–7118311183
75. Griffioen KJ,Wan R,Okun E,et al. GLP-1 receptor stimulation depresses heart rate variability and inhibits neurotransmission to cardiac vagal neurons. Cardiovasc ResYear: 2010;14:1–7


[Figure ID: BMJOPEN2012001986F1]
Figure 1 

PRISMA flow diagram. GLP-1, glucagon-like peptide-1.

[Figure ID: BMJOPEN2012001986F2]
Figure 2 

Effect of liraglutide on heart rate in patients with type 2 diabetes.

[Figure ID: BMJOPEN2012001986F3]
Figure 3 

Effect of exenatide on heart rate in patients with type 2 diabetes.

[Figure ID: BMJOPEN2012001986F4]
Figure 4 

GLP-1 agonists' effect on systolic blood pressure in patients with type 2 diabetes. GLP-1, glucagon-like peptide-1.

[Figure ID: BMJOPEN2012001986F5]
Figure 5 

GLP-1 agonists' effect on diastolic blood pressure in patients with type 2 diabetes. GLP-1, glucagon-like peptide-1.

[Figure ID: BMJOPEN2012001986F6]
Figure 6 

GLP-1 agonists' effects on body weight. GLP-1, glucagon-like peptide-1.

[TableWrap ID: BMJOPEN2012001986TB1] Table 1  

Characteristics of included studies

Study Comparisons Duration (weeks) Study population/ethnicity Country Body weight groups included Balanced male/female? Mean age Standardised diet/exercise Background OAD
Apovian et al42 EX/PLAC 24 MR US OW >60% F 54.8 Y MET and/or SU
Barnett et al43 EX/IG 16 MR Multinational N/OW/OB Y 54.9 N MET or SU
Bergenstal et al44 EX/BIAsp 24 MR US N/OW Y 52.6 N MET and SU
Bergenstal et al45 EX LAR vs PIO
26 MR Multinational N/OW/OB Y 52.3 N MET
Buse et al46 EX/PLAC 30 MR US OW/OB 60% M 55.3 N SU
Buse et al47 IG+EX/ IG+PLAC 30 MR Multinational N/OW/OB Y 59.0 N MET or PIO
Davies et al48 EX/IG 26 MR GB OW/OB >60% M 56.5 N Two or three OADS: MET, SU, or TZD
DeFronzo et al49 EX/PLAC 30 MR US OW/OB Y 53.0 N MET
DeFronzo et al50 EX vs ROSI 20 MR US OW/OB Y 56.0 N MET
Derosa et al51 EX/GLIB 52 W IT OW/OB Y 56.5 Y MET
Derosa et al52 EX/GLIM 52 CAUC IT OW/OB Y 55.5 Y MET
Diamant et al53 EX LAR/IG 26 MR Multinational OW/OB Y 58.0 N MET
Gallwitz et al54 EX/BIAsp 26 MR GER OW/OB Not reported 57.0 N MET
Gallwitz et al55 EX/GLIM Up to 4.5 years MR Multinational OW/OB Y 56.0 N MET
Gao et al56 EX/PLAC 12 C/I/K/T Multinational N/OW/OB Y 54.0 N MET and/or SU
Garber et al57 LIR/GLIM 52 MR US/MEX N/OW/OB Y 53.0 N Nil—previous OAD withdrawn
Gill et al58 EX/PLAC 12 MR CAN/NL OW/OB Y 55.6 N MET and/or TZD
Heine et al59 EX/IG 26 MR Multinational OW/OB Y 58.9 N MET and SU
Kadowaki et al60 EX/PLAC 12 JP JP N/OW/OB >60% M 60.3 N SU, with or without either BG or TZD
Kendall et al61 EX/PLAC 30 MR US OW/OB Y 55.3 Y MET and SU
Kim et al62 EX LAR/PLAC 15 MR US OW/OB 60% M 53.7 Y MET
Liutkus et al63 EX/PLAC 26 MR Multinational OW/OB Y 54.7 N TZD with or without MET
Marre et al64 LIR/PLAC/ROSI 26 MR Multinational N/OW/OB Y 56.0 N SU
Moretto et al65 EX/PLAC 24 MR Multinational OW/OB Y 54.0 Y DRUG NAIVE
Nauck et al66 EX/PIA 52 MR Multinational OW/OB Y 58.5 N SU and MET
Nauck et al67 LIR/GLIM/PLAC 26 MR Multinational N/OW/OB Y 56.7 N MET
Pratley et al68 LIR/SIT 26 MR Multinational N- OW-OB Y 55.3 N MET
Russell-Jones et al69 LIR/IG/PLAC 26 MR Multinational N/OW/OB Y 57.5 N MET and SU
Russell-Jones et al70 EX LAR/MET
26 MR Multinational N/OW/OB Y 54.0 N DRUG NAIVE
Yang et al71 LIR/GLIM 16 C/K/I Multinational N/OW/OB Y 53.3 N MET
Zinman et al72 EX/PLAC 16 MR Multinational OW/OB Y 56.1 N TZD with or without MET
Zinman et al73 LIR/PLAC 26 MR US/CAN N/OW/OB Y 55.0 N MET and ROSI

BG, Biguanide; BIAsp, biphasic insulin aspart; C, Chinese; CAN, Canada; CAUC, Caucasian; EX LAR, exenatide long-acting release; EX, exenatide; GB, Great Britain; GER, Germany; GLIB, glibenclamide; GLIM, glimepiride; I, Indian; IG, insulin glargine; IT, Italy; JP, Japan; JP, Japanese; K, Korean; LIR, liraglutide; MET, metformin; MEX, Mexico; MR, Multiracial; N, normal weight; NL, the Netherlands; OAD, oral antidiabetic drug; OB, obese; OW, overweight; PIO, pioglitazone; PLAC, placebo; ROSI, rosiglitazone; SITA, sitagliptin; T, Taiwanese; US, the USA; W, White.

[TableWrap ID: BMJOPEN2012001986TB2] Table 2  

Risk of bias across included studies

Article Categories:
  • Diabetes and Endocrinology
    • Research
Article Categories:
  • 1506
  • 1688
  • 1683
  • 1723

Keywords: therapeutics.

Previous Document:  Abdominal fat distribution and its relationship to brain changes: the differential effects of age on...
Next Document:  Determinants of self-reported smoking and misclassification during pregnancy, and analysis of optima...