108Biologic significance of healed culprit plaques in stable angina versus acute coronary syndromes

Background

Healed plaques, the signature of prior subclinical plaque destabilization, are frequently found in autopsy studies and have recently been described in patients with acute coronary syndromes (ACS).

Objectives

To compare the prevalence and features of plaque vulnerability of healed culprit lesions in stable angina pectoris (SAP) versus ACS patients by using Optical Coherence Tomography (OCT).

Methods

A total of 752 patients were included: 376 patients with SAP were selected using propensity score matching, comparable to 376 patients with ACS. Healed plaques were identified using established criteria, defined as layers of different optical density on OCT. Healed plaque prevalence along with angiographic and OCT findings were compared between the two groups.

Results

Healed plaques were more frequent in SAP than in ACS patients (42.0% vs 28.7%, p<0.001). LDL-cholesterol and high sensitive C-reactive protein (hs-CRP) levels were significantly lower in SAP patients with layered plaque as compared to ACS patients with layered plaque [97.9±36.9 mg/dL vs 116.7±39.2 mg/dL, p<0.001; 0.20 (0.10–0.83) mg/L vs 4.98 (1.00–11.32) mg/L, p<0.001, respectively]. Thin-cap fibroatheroma, macrophage accumulation and microvessels were significantly less frequent in layered plaques in SAP patients as compared to those in ACS patients (12.7% vs 56.5%, p<0.001, 7.0% vs 79.6%, p<0.001, and 20.3% vs 43.5%, p<0.001, respectively). Calcifications were found more frequently among layered plaques in SAP patients than in ACS patients (51.3% vs 33.6%, p=0.006).

Conclusions

Healed plaques, detected more frequently in SAP than in ACS patients, portend different atherosclerotic backgrounds. In SAP patients, plaque destabilization frequently does not lead to occlusive thrombosis, possibly due to low level of local vulnerability and systemic inflammation. In ACS patients, the presence of high level of local vulnerability and systemic inflammation may play an important role in occlusive thrombus formation, resulting in terminating the cycles of subclinical thrombosis and healing.

P5617Repeatability of instantaneous wave-free ratio in comparison with fractional flow reserve

Background

Instantaneous wave-free ratio (iFR) has been recently introduced as an adenosine free alternative for fractional flow reserve (FFR) to assess the functional significance of epicardial coronary stenosis. Little is known, however, regarding the repeatability and stability of iFR in comparison with FFR.

Purpose

The aim of this study was to evaluate the repeatability of iFR and compare it to that of FFR.

Methods

Patients with stable coronary artery disease who underwent physiological assessment twice within 90 days were enrolled. Repeated measurements were performed at diagnostic and therapeutic catheterization in about 70% of studied population. The remaining patients were measured twice for non-culprit lesion assessment at primary PCI and subsequent non-culprit and ischemia-documented lesion PCI. The calculation of iFRmatlab from DICOM pressure tracing data of resting state was performed using a fully automated off-line software algorithm in a blind fashion. FFR values were also measured by a fully automated algorithm in the same core laboratory by using hyperemic pressure tracing data. The repeatability of the two indices were evaluated and compared. The inter-rater agreement between iFRmatlab and FFR values of two measurements was assessed by κ coefficient. The pressure rate product during each assessment was also documented and evaluated.

Results

Ninety-three lesions from 92 patients were included in the study. The time interval between the two assessments was 38.4±19.0 days. iFRmatlab and FFR both showed significant correlation within the two assessments (iFRmatlab: r=0.75, 95% confidence interval, 0.64 to 0.83; mean difference, −0.006 [−0.18 to −0.01], FFR: r=0.86, 95% confidence interval, 0.79 to 0.90; mean difference, 0.004 [−0.07 to 0.03]). The inter-rater agreement of functional ischemia for iFRmatlab and FFR were κ=0.449 and κ=0.732, respectively. Although the prevalence of functional ischemia during the first and second assessment were consistent for both indices (iFRmatlab: 70.0%/67.7%, FFR: 86.0%/ 86.0%), significant difference was observed in the prevalence of clinical disagreement on the diagnosis of functional ischemia (FFR=0.80, iFR=0.89 used as cut-off values, respectively) between the first and second assessment among the two indices (iFRmatlab: 6.5%, FFR: 23.7%, p=0.002). iFRmatlab was significantly associated with pressure rate product during the examination compared to FFR (iFRmatlab: r= −0.25, 95% confidence interval, −0.43 to −0.04, P=0.018, FFR: r=−0.08, 95% confidence interval, −0.28 to −0.13, p=0.467).

Conclusion

Our results suggested that iFRmatlab showed lower repeatability and reliability for decision making compared to FFR. The instability of iFRmatlab potentially derives at least in part from its association with heart rate and blood pressure product.

P2703Impact of subtended myocardial mass on the assessment of functional ischemia as evaluated by FFR and QFR

Background

The fractional flow reserve (FFR) becomes a standard practice for revascularization decision-making in evaluating the functional significance of angiographically intermediate epicardial coronary stenosis. The quantitative flow ratio (QFR) is a novel method for rapid computational estimation of FFR without pressure wire and hyperemic induction. FFR has been reported to be associated with not only epicardial stenosis but also subtended myocardial mass (Vsub). In contrast, the relationship between QFR and Vsub has not been clarified.

Purpose

We sought to examine if subtended myocardial mass (Vsub) assessed by coronary computed tomography showed a significant relationship with QFR in comparison with FFR.

Methods and results

We performed a post-hoc analysis of 152 territories (LAD 116, RCA 25 and LCX 11 lesions) with angiographically intermediate-to-severe stenosis in 152 patients who underwent FFR assessment. The median FFR and QFR values were 0.76 (0.64–0.84) and 0.76 (0.72–0.83), respectively. The median diameter stenosis (%DS) and minimum lumen diameter (MLD) were 54.5 (43.9–64.2) and 1.2 (0.9–1.6), respectively. In total, 123 (80.9%) and 29 (19.1%) lesions showed concordant and discordant FFR and QFR functional classifications, respectively. The ability of Vsub/MLD2 to discriminate lesions with FFR≤0.80 and QFR≤0.80 was assessed compared with QCA data. FFR values were associated with Vsub (R=0.37, P<0.001). In contrast, a trend albeit no significant linear relationshipwas detected between QFR and Vsub (R=0.15, P=0.060). The area under the curve (AUC) of Vsub/MLD2 predicting FFR≤0.80 (0.88: 95% confidence interval [CI], 0.83–0.94)was significantly better than that of MLD (0.80: 95% [CI], 0.72–0.88) (P<0.001). On the other hand, the AUC of Vsub/MLD2 predicting QFR≤0.80 (0.82: 95% [CI], 0.75–0.90) was similar to that of MLD (0.80: 95% [CI], 0.72–0.87) (P=0.276). Multivariate analysis showed that the value of Vsub/MLD2 was an independent predictor of FFR≤0.80 (odds ratio [OR]: 1.09, 95% [CI]: 1.03–1.15, P=0.002), whereas it was not an independent predictor of QFR≤0.80.

Conclusions

Subtended cardiac mass volume derived from CT segmentation improved the diagnostic performance of angiography-derived parameters to identify ischemia-producing lesions when FFR used as a reference standard, whereas QFR showed non-significant relationship with subtended cardiac mass.

6113Gender differences in long-term outcomes in patients with deferred revascularization following fractional flow reserve assessment: international collaboration registry of physiologic evaluation

Background

Studies of sex differences in fractional flow reserve (FFR) measurements have shown that in comparison with men, angiographic lesions of similar visual severity are less likely to be ischemia producing in women. Gender specific differences may influence revascularization decision making and prognosis after deferred revascularization following FFR measurement.

Purpose

This study sought to investigate the gender difference in long-term prognosis of patients of deferred revascularization following FFR assessment.

Methods

A total of 879 patients (879 vessels) with deferred revascularization with FFR >0.75 who underwent FFR and CFR measurements were enrolled from 3 countries (Korea, Japan, and Spain). Long-term outcomes were assessed in 649 men and 230 women by the patient-oriented composite outcome (POCO, a composite of any death, any myocardial infarction [MI], and any revascularization). We applied inverse-probability weighting (IPW) based on propensity scores to account for differences at baseline between women and men (age, hypertension, hyperlipidemia, diabetes mellitus, lesion location, clinical status, FFR, Reference diameter, Diameter stenosis, lesion length). The median follow-up duration was 1855 days (745–1855 days).

Results

Median FFR values were 0.88 (0.83–0.93) in men and 0.89 (0.85–0.94) in women, respectively. The occurrences of POCO were significantly high in men compared with that in women (10.5% vs 4.2%, P=0.007). Kaplan–Meier analysis revealed that women had a significantly lower risk of POCO (χ2=7.2, P=0.007). Multivariate COX regression analysis revealed that age, male, diabetes mellitus, diameter stenosis, lesion length, and coronary flow reserve were independent predictors of POCO. After applying IPW, the hazard ratio of male for POCO was 2.20 (95% confidence interval: 1.12 to 4.33, P=0.023).

Conclusion

This large multinational study reveals that long-term outcome differs between women and men in favour of women after FFR-guided revascularization deferral.

Acknowledgement/Funding

None

P2239The association between global coronary flow reserve and coronary inflammation assessed by fat attenuation index on computed tomography in patients with acute coronary syndrome

Background

Impaired global coronary flow reserve (G-CFR) is known to predict worse outcomes in patients with coronary artery disease. Phase contrast cine-magnetic resonance imaging (PC-CMR) of the coronary sinus (CS) is a promising approach for quantifying coronary sinus flow (CSF) and global coronary flow reserve (G-CFR) without the need for ionizing radiation, radioactive tracers, or intravascular catheterization. Although G-CFR impairment has been previously reported to be linked with endothelium dysfunction and subsequent atherosclerosis, the relationship between coronary inflammation and absolute coronary blood flow volume or coronary flow reserve remains elusive.

Purpose

We evaluated the association between G-CFR by quantifying CSF using PC-CMR and the extent of coronary inflammation in patients with ACS treated with emergent percutaneous coronary intervention (PCI).

Methods

The study enrolled 107 ACS patients who underwent uncomplicated emergent PCI within 48 hours of symptom onset and coronary CT angiography were performed before PCI. Proximal 40-mm segments of all three major epicardial coronary vessels were examined. Coronary inflammation was assessed by the CT fat attenuation index of perivascular adipose tissue (FAI−PVAT) defined as the mean attenuation of the perivascular adipose tissue (−190 to −30 Hounsfield units (HU)) in a layer of tissue within a radial distance from the outer coronary artery wall equal to the diameter of the vessel, as previously reported. CMR images were acquired to assess absolute CSF at rest and during maximum hyperemia within 30 days after emergent PCI and revascularization of non-culprit significant lesions. The patients were divided into 4 groups according to the number of inflamed vessels (defined as 0, 1, 2, 3 vessels with FAI ≥−70.1 HU).

Results

In the final analysis of 102 patients (mean age 64, Male 65 (63.7%)) including 77 patients with non-ST-segment elevation myocardial infarction (NSTEMI) (75.5%) and 25 patients with unstable angina pectoris (UAP), 25, 30, 26, 21 patients exhibited none, 1, 2, 3 inflamed vessels with FAI ≥−70.1 HU, respectively. Rest and maximal hyperemic CSF and corrected G-CFR were 1.17 [0.63, 1.71] vs 1.36 [1.05, 1.67] vs 1.21 [0.83, 1.94] vs 1.35 [0.96, 1.67] ml/min/g; P=0.61, 3.26 [2.62, 2.99] vs 3.50 [2.60, 4.03] vs 3.34 [1.78, 4.20] vs 2.48 [1.54, 3.43]; P=0.061, 2.95 [2.05, 4.30] vs 2.63 [1.80, 3.56] vs 2.15 [1.37, 2.91] vs 2.18 [1.46, 2.42]; P=0.018, respectively. G-CFR was significantly lower in group with increased number of inflamed vessels.

Conclusions

In ACS patients successfully revascularized within 48 hours of onset, G-CFR obtained by noninvasive PC-CMR significantly associated with the prevalence of inflamed vessels detected by coronary CT. Further large population study is warranted to test the hypothesis that the extent of coronary inflammation before coronary revascularization in patients with ACS might provide prognostic information.

P5251Prognostic value of unrecognized myocardial infarction detected by cardiac magnetic resonance imaging in patients presenting with first acute myocardial infarction

Background

Unrecognized myocardial infarction (UMI) has been reported to be strongly associated with worse outcome in patients with cardiovascular disease. Cardiac magnetic resonance (CMR) imaging is a useful instrument for the assessment of pathological and functional conditions.

Purpose

This study sought to evaluate the prognostic value of the presence of unrecognized non-infarct-related late gadolinium enhancement (non-IR LGE) evaluated by cardiac magnetic resonance imaging in patients presenting with a first acute myocardial infarction (AMI).

Methods

We studied 311 AMI patients including 213 STEMI and 98 NSTEMI patients without the history of prior MI who underwent uncomplicated primary or emergent PCI within 48 hours of symptom onset between October, 2012 and June, 2017. CMR images were acquired at 28 [21, 32] days after primary/emergent PCI. UMI was defined as having LGE separately in the different and remote area from the perfused territory by infarct-related artery. In case of multiple LGE areas of infarction, the coronary angiography findings were used to support identification of the area corresponding to the culprit artery of AMI. The association of CMR variables and other clinical characteristics with major adverse cardiac events (cardiac death, nonfatal myocardial infarction, nonfatal stroke) were investigated.

Results

Forty-six patients (14.8%) showed UMI defined by the presence of non-IR LGE (27 STEMI and 19 NSTEMI). During the follow up for 830 [385, 1309] days, cardiovascular death occurred in 7 patients (2.3%), and non-fatal MI and non-fatal stroke occurred in 10 and 1 patients, respectively (3.2%, 0.3%, respectively). There was no significant difference in the prevalence of UMI and incidence of MACE between the patients with STEMI and NSTEMI (p=0.13, p=0.11, respectively). Event-free survival was significantly worse in patients with UMI (log-rank χ2=16.3, P=0.001) in a total cohort. Cox proportional hazards analysis showed that UMI was independent predictors of adverse cardiac events during follow-up in patients with first MI (hazard ratio, 7.60, 95% confidence interval, 2.78–20.8, p=0.0001).

Conclusions

In first AMI patients, UMI defined by non-IR LGE obtained by noninvasive CMR provides significant prognostic information. Early detection of UMI by CMR may help risk stratification of patients with AMI and support adjunctive aggressive patient management such as strong statin therapy and life style intervention.

P6393Differences in coronary inflammation between the culprit and non-culprit vessels assessed by fat attenuation index on computed tomography in patients with acute coronary syndromes

Background

Inflammation is linked with progression of coronary atherosclerosis. Recent studies have reported the association between elevated perivascular fat attenuation index (FAI) on computed tomography (CT) and worse cardiac outcomes in patients with coronary artery disease.

Purpose

We aimed to investigate the differences in FAI-defined peri-coronary inflammation status between the culprit and non-culprit vessels in patients with acute coronary syndromes (ACS).

Methods

A total of 78 ACS patients with left anterior descending coronary arteries (LAD) as a culprit vessel who underwent coronary CT angiography and invasive coronary angiography were studied. Proximal 40-mm segments of the LAD and the right coronary artery (RCA) were traced. Coronary inflammation was assessed by the FAI defined as the mean CT attenuation value of perivascular adipose tissue (−190 to −30 Hounsfield units [HU]) in a layer of tissue within a radial distance from the outer coronary artery wall equal to the diameter of the vessel. All patients were divided into two groups according to the values of FAI in the LAD: high FAI group (FAI-LAD > median; n=39) and low FAI group (FAI-LAD ≤ median; n=39). Patient characteristics, angiographic and CT findings were compared between the two groups.

Results

In a total of 78 patients, median FAI in the LAD was −70.20 (interquartile range, −74.81 to −64.58) HU. High FAI group was associated with male sex and lower left ventricular ejection fraction compared with Low FAI group. Minimal lumen diameter, reference diameter, diameter stenosis, and lesion length on quantitative coronary angiography analysis and coronary artery calcium score on CT was not different between the groups. FAI in the RCA was also higher in High FAI group than that in Low FAI group (−67.64±8.31 vs. −76.47±6.25 HU, P<0.001). Paired t-test comparison demonstrated that culprit vessel showed higher FAI than the non-culprit vessel (−69.85±7.74 vs. −72.11±8.54 HU, P=0.013).

Conclusions

In ACS patients with culprit LAD lesions, FAI-defined peri-coronary inflammation status is higher in the culprit vessel than in the non-culprit vessel.

P3585Prognostic value of the assessment of coronary sinus flow by phase contrast cine-magnetic resonance imaging in patients with acute coronary syndrome

Background

Phase contrast cine-magnetic resonance imaging (PC-CMR) of the coronary sinus (CS) is a promising approach for quantifying global coronary sinus flow (CSF) and global coronary flow reserve (G-CFR) without the need for ionizing radiation, radioactive tracers, or intravascular catheterization.

Purpose

We evaluated the prognostic value of G-CFR by quantifying CSF using PC-CMR in patients with ACS treated with primary or emergent percutaneous coronary intervention (PCI).

Methods

The study prospectively enrolled 387 ACS patients who underwent uncomplicated primary or emergent PCI within 48 hours of symptom onset. Breath-hold PC-CMR images of CS were acquired to assess absolute CSF at rest and during maximum hyperemia within 30 days after primary PCI and revascularization of functionally significant non-culprit lesions of ACS. The association of G-CFR and baseline clinical characteristics with major adverse cardiac events (cardiac death, nonfatal myocardial infarction, late revascularization, or hospitalization for congestive heart failure) was investigated.

Results

In the final analysis of 366 patients (Male 294 (80.3%), mean age 65) including 233 patients (63.7%) with ST-segment elevation myocardial infarction (STEMI) and 133 patients (36.3%) with non-ST-segment elevation acute coronary syndrome (NSTE-ACS), rest and maximal hyperemic CSF and corrected G-CFR were 1.24 [0.83, 1.71] ml/min/g, 2.56 [1.87, 3.66] ml/min/g, and 2.20 [1.53, 3.17], respectively. During a median follow-up of 16 months, MACE occurred in 84 patients (cardiac death: 9, nonfatal myocardial infarction: 11, late revascularization: 59, hospitalization for congestive heart failure: 5). Cardiac event-free survival was significantly worse in patients with a corrected G-CFR <2.00 (log-rank χ2=20.2, P<0.001). Cox proportional hazards analysis showed that corrected G-CFR were independent predictors of adverse cardiac events during follow-up in patients with STEMI (hazard ratio, 0.66, 95% confidence interval, 0.51–0.85, p=0.001) and NSTE-ACS (hazard ratio, 0.64, 95% confidence interval, 0.43–0.95, p=0.026), respectively.

Conclusions

In ACS patients successfully revascularized within 48 hours of onset, G-CFR obtained by noninvasive PC-CMR provided significant prognostic information independent of infarction size and conventional risk scores.

Concerns and Side Effects of Azathioprine During Adalimumab Induction and Maintenance Therapy for Japanese Patients With Crohn's Disease: A Subanalysis of a Prospective Randomised Clinical Trial [DIAMOND Study]

BACKGROUND

Combining a thiopurine with the human anti-tumour necrosis factor-α monoclonal antibody adalimumab for Crohn's disease [CD] treatment is controversial with regard to efficacy and safety. By conducting a subanalysis of a multicentre, randomised, prospective, open-label trial [the DIAMOND study, UMIN registration number 000005146], we studied the risk of discontinuation of thiopurine in combination with adalimumab.

METHODS

In the preceding DIAMOND study, we analysed the: [i] timing and reasons for dropout in the monotherapy group and combination group; [ii] risk factors for dropout in the combination group.

RESULTS

There was no significant difference in the dropout rate up to Week 52 between the monotherapy group and combination group [p = 0.325]. The main reason for study dropout was active CD in the monotherapy group, whereas it was adverse effects in the combination group [Fisher's exact test, p <0.001]. Kaplan-Meier analyses revealed significantly earlier dropout in the combination group [log-rank test, p = 0.001]. Multivariable analysis revealed low body weight to be a risk for dropout due to adverse effects in the combination group.

CONCLUSIONS

Combination of azathioprine with adalimumab resulted in dropout in the early stage of the study due to side effects of azathioprine, in comparison with late dropout due to active CD in the adalimumab monotherapy group.

Guidelines for the management of Helicobacter pylori infection in Japan: 2016 Revised Edition

BACKGROUND

Since "Helicobacter pylori (H. pylori) infection" was set as the indication in the Japanese Society for Helicobacter Research (JSHR) Guidelines 2009, eradication treatment for H. pylori gastritis is covered under insurance since 2013 in Japan, and the number of H. pylori eradication has rapidly increased. Under such circumstances, JSHR has made the third revision to the "Guidelines for diagnosis and treatment of H. pylori infection" for the first time in 7 years.

METHODS

The Guideline Committee held 10 meetings. Articles published between the establishment of the 2009 Guidelines and March 2016 were reviewed and classified according to the evidence level; the statements were revised on the basis of this review. After inviting public comments, the revised statements were finalized using the Delphi method.

RESULTS

There was no change in the basic policy that H. pylori infectious disease is an indication for eradication. Other diseases presumed to be associated with H. pylori infection were added as indications. Serum pepsinogen level, endoscopic examination, and X-ray examination were added to the diagnostic methods. The effects of 1-week triple therapy consisting of potassium-competitive acid blocker (P-CAB), amoxicillin, and clarithromycin have improved, and high eradication rates can also be expected with proton pump inhibitors (PPI) or P-CAB combined with amoxicillin and metronidazole. If the susceptibility test is not performed, the triple PPI or P-CAB/amoxicillin/metronidazole therapy should be chosen, because the PPI/amoxicillin/metronidazole combination demonstrated a significantly higher eradication rate than PPI/amoxicillin/clarithromycin. In the proposal for gastric cancer prevention, we divided gastric cancer prevention measures by age from adolescent to elderly, who are at an increased gastric cancer risk, and presented measures for gastric cancer prevention primarily based on H. pylori eradication.

CONCLUSION

We expect the revised guidelines to facilitate appropriate interventions for patients with H. pylori infection and accomplish its eradication and prevention of gastric cancer.

Color change in Perlodel® tablets induced by LED lighting - photolysis of bromocriptine mesylate

Various types of fluorescent lights are found in the dispensing rooms of medical facilities, such as hospitals and pharmacies, in Japan. However, to reduce electric power consumption, it was necessary to evaluate the substitution of fluorescent lighting with light emitting diode (LED) lighting, which has become widespread in recent years. We subjectively evaluated several types of medicines stored under various light sources and found that different color changes were induced in tablets. In this study, we focused on Perlodel ® tablets, containing 2.5 mg bromocriptine mesylate, as an example for the objective evaluation of the differences in the color change of tablets when stored under LED lighting and fluorescent lighting. High-performance liquid chromatography (HPLC) analysis of part of the tablet surface area revealed a change from white to light brown or dark brown after 28 days of irradiation, with a residual concentration of bromocriptine mesylate of 85.5 % under fluorescent lighting, 85.6 % under daylight-color LED lighting, 90.3 % under bulb-color LED lighting, and 99.2 % in the dark. In addition, the ultraviolet (UV)-visible spectral study of the absorbance of a photo-product at 400-550 nm indicated that the color change of the Perlodel^® 2.5 mg tablet was caused by photochemical degradation of bromocriptine mesylate. Thus, this analysis of the photochemical changes in drugs stored under different light sources demonstrated the potency of LED lights. Through the objective evaluation of the color change, the cause of the color change was determined; this will allow us to develop a strategy that minimizes possible disadvantages to patients, such as a decrease in treatment efficacy owing to decomposition of the main component or adverse caused by decomposed matter.

Hayabusa2 arrives at the carbonaceous asteroid 162173 Ryugu-A spinning top-shaped rubble pile

The Hayabusa2 spacecraft arrived at the near-Earth carbonaceous asteroid 162173 Ryugu in 2018. We present Hayabusa2 observations of Ryugu's shape, mass, and geomorphology. Ryugu has an oblate "spinning top" shape, with a prominent circular equatorial ridge. Its bulk density, 1.19 ± 0.02 grams per cubic centimeter, indicates a high-porosity (>50%) interior. Large surface boulders suggest a rubble-pile structure. Surface slope analysis shows Ryugu's shape may have been produced from having once spun at twice the current rate. Coupled with the observed global material homogeneity, this suggests that Ryugu was reshaped by centrifugally induced deformation during a period of rapid rotation. From these remote-sensing investigations, we identified a suitable sample collection site on the equatorial ridge.

Built environment and cardio-metabolic health: systematic review and meta-analysis of longitudinal studies

Built environment attributes may be related to cardio-metabolic diseases (e.g. type 2 diabetes, heart disease and stroke) and their risk factors, potentially by influencing residents' physical activity. However, existing literature reviews on the built environment and health for the most part focus on obesity as the outcome and rely on cross-sectional studies. This systematic review synthesized current evidence on longitudinal relationships between built environment attributes and cardio-metabolic health outcomes among adults and on the potential mediating role of physical inactivity. By searching eight databases for peer-reviewed journal articles published in the English language between January 2000 and July 2016, the review identified 36 articles. A meta-analysis method, weighted Z-test, was used to quantify the strength of evidence by incorporating the methodological quality of the studies. We found strong evidence for longitudinal relationships of walkability with obesity, type 2 diabetes and hypertension outcomes in the expected direction. There was strong evidence for the impact of urban sprawl on obesity outcomes. The evidence on potential mediation by physical activity was inconclusive. Further longitudinal studies are warranted to examine which specific built environment attributes influence residents' cardio-metabolic health outcomes and how physical inactivity may be involved in these relationships.