G lobally, cardiovascular disease (CVD) is the leading cause of death accounting for 31% in 2008.1 Obesity is an independent predictor of CVD and weight loss has been shown to improve many obesity-related risk factors. 2 However, there are few studies investigating the effect of weight loss on cardiovascular end points. The Trial of Nonpharmacological Interventions in the Elderly enrolled subjects >60 years with hypertension to investigate the effect of weight loss on blood pressure and cardiovascular outcomes.3 After a median follow-up of 29 months, the hazard ratio (HR) for a cardiovascular end point or diagnosis of high blood pressure in the weight reduction group was 0.64 (95% confidence interval [CI], 0.49, 0.85; P=0.002). 4 More recently, the Look AHEAD trial (n=5145) failed to show a benefit of weight reduction on cardiovascular end points in subjects with type 2 diabetes mellitus after a median followup of 9.6 years. 5 In the Look AHEAD trial, the mean weight loss in the intervention group was 6%, compared with 3.5% in the control group.Carotid femoral pulse wave velocity (cfPWV) is considered the gold standard method for measuring arterial stiffness because it measures the propagation of the forward pressure at the level of the aorta.6 A meta-analysis of individual participant data from 17 studies (17 635 participants) showed that cfPWV was an independent predictor of coronary heart disease (HR, 1.23; 95% CI, 1.11 to 1.35), stroke (HR, 1.28; 95% CI, 1.16 to 1.42), CVD (HR, 1.30; 1.18 to 1.43), CVD mortality (HR, 1.28; 95% CI, 1.15 to 1.43), and all-cause mortality (HR, 1.17; 1.11 to 1.22), after adjustment for established risk factors. Furthermore, the addition of cfPWV to conventional Framingham risk factors improved 10-year CVD risk prediction by 13% in those at intermediate risk of CVD. 7 Many studies indicate that weight loss may improve pulse wave velocity (PWV), although in about half of the studies the change is not statistically significant. A meta-analysis has not been conducted to assess the overall effect of weight loss. The primary aim of this meta-analysis of intervention trials is © 2014 American Heart Association, Inc. Objective-To conduct a systematic review and meta-analysis of clinical trials involving adults, to determine the effect of weight loss induced by energy restriction with or without exercise, antiobesity drugs or bariatric surgery on pulse wave velocity (PWV) measured at all arterial segments. Approach and Results-A systematic search of Pubmed (1966Pubmed ( to 2014, EMBASE (1947EMBASE ( to 2014, MEDLINE (1946MEDLINE ( to 2014, and the Cochrane Library (1951 to 2014) was conducted and the reference lists of identified articles were searched to find intervention trials (randomized/nonrandomized) that aimed to achieve weight loss and included PWV as an outcome. The search was restricted to human studies. Two independent researchers extracted the data. Data were analyzed using Comprehensive Meta Analysis version 2 using random effects analysis. A total of 22 studies wer...
