PROSPERO International prospective register of systematic reviews
Coronary artery calcium prediction of cardiovascular events and all-cause mortality in patients with type 2 diabetes mellitus: a systematic review and meta-analysis of observational studies
Caroline Kramer, Ravi Retnakaran, Bernard Zinman, Luis Canani, Jorge Gross, Ticiana Rodrigues
Caroline Kramer, Ravi Retnakaran, Bernard Zinman, Luis Canani, Jorge Gross, Ticiana Rodrigues. Coronary artery calcium prediction of cardiovascular events and all-cause mortality in patients with type 2 diabetes mellitus: a systematic review and meta-analysis of observational studies.
Available from http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42012002915
The question to be addressed by this review/meta-analysis is whether coronary artery calcium predicts cardiovascular event and/or all-cause mortality in patients with type 2 diabetes mellitus.
We selected relevant studies published between 1950, and September 4, 2012, from EMBASE, PubMed, Cochrane Library databases, Clinical Trials.gov, American Diabetes Association meetings (abstracts book) 2011 and 2012, European Association for the Study of Diabetes meetings (abstract book) 2011 and 2012.
We used the following combined text and Medical Subject Heading terms: coronary calcium and type 2 diabetes mellitus. The complete search used for Pubmed was(Calcium score [text] OR coronary artery calcification [text] OR coronary artery calcium [text]) AND ("Diabetes Mellitus"[Mesh] OR "Diabetes Mellitus, Type 2"[Mesh])
Types of study to be included
Only prospective observational studies will be included.
Condition or domain being studied
We will include studies that evaluated coronary artery calcium for the prediction of events in patients with type 2 diabetes
Studies will be consider eligible for inclusion if they were conducted in adults aged 18 years or older with type 2 diabetes, evaluated coronary artery calcium at baseline and evaluated the incidence of any events (cardiovascular events and/or all-cause mortality).
The exclusion criteria are as follow:
(i) cross-sectional or retrospective studies;
(ii) duplicate publications or substudies of included studies;
(iii) studies that lack data for analysis.
We will consider the presence of any coronary artery calcification as the exposure.
The control group (non-exposed group) will be the group without any coronary artery calcium.
Any cardiovascular event and/or all-cause mortality.
Risk of bias (quality) assessment
Risk of bias will be evaluated according to New-Castle-Ottawa quality assessment scale for cohort studies. Study quality assessment will include selection criteria, comparability and outcome assessment.
Strategy for data synthesis
An overall relative risk (RR) will be calculated to assess the predictive value of coronary artery calcium for all-cause mortality and/or CV events. We will use the Cochrane Q test to evaluate heterogeneity between studies and consider a threshold P value less than 0.1 as statistically significant. We will also use the I-squared testing to evaluate the magnitude of the heterogeneity between studies. We will calculate the pooled estimates of the mean differences in outcomes before and after the intervention by using a random-effects model (DerSimonian–Laird method) to adequately account for the additional uncertainty associated with study–study variability in the effect of the intervention.
Receiver operating characteristic (ROC) curves were constructed to obtain the pooled estimates of sensitivity and specificity of coronary artery calcium for the development of outcomes. The average likelihood ratio of the positive and negative test result will be calculated.
Analysis of subgroups or subsets
Exploration of subgroups will be based on meta-regression models.
Contact details for further information
Caroline Kaercher Kramer
Leadership Sinai Centre for Diabetes
Mount Sinai Hospital
60 Murray Street, Suite L5-025, Mailbox 21
Organisational affiliation of the review
Dr Caroline Kramer, Leadership Sinai Centre for Diabetes Dr Ravi Retnakaran, Leadership Sinai Centre for Diabetes Dr Bernard Zinman, Leadership Sinai Centre for Diabetes Dr Luis Canani, Hospital de Clinicas de Porto Alegre/Brazil Dr Jorge Gross, Hospital de Clinicas de Porto Alegre/Brazil Dr Ticiana Rodrigues, Hospital de Clinicas de Porto Alegre/Brazil
Anticipated or actual start date
01 September 2012
Anticipated completion date
31 October 2012
C.K.K holds a Canadian Diabetes Association (CDA) Postdoctoral Fellowship Award. R. R. holds an Ontario Ministry of Research and Innovation Early Researcher Award. B. Z. holds the Sam and Judy Pencer Family Chair in Diabetes Research at Mount Sinai Hospital and University of Toronto.
Formal screening of search results against eligibility criteria
Risk of bias (quality) assessment
PROSPERO This information has been provided by the named contact for this review. CRD has accepted this information in good faith and registered the review in PROSPERO. CRD bears no responsibility or liability for the content of this registration record, any associated files or external websites.