Table 1. Characteristics of included studies .
| AUTHOR | YEAR | PLACE | CASE | CONTROL | Type of CAD |
| F. Rahimi(15) | 2001 | Tehran | 100 | 100 | Coronary Heart Disease |
| N. Sarrafzadeh(16) | 2001 | Isfahan | 52 | 55 | Myocardial Infarction |
| B. Rahnema(17) | 2001 | Tabriz | 104 | 100 | Myocardial Infarction |
| M. AghaJani(18) | 2002 | Tehran | 100 | 90 | Coronary Heart Disease |
| F. Jalali(19) | 2003 | Babol | 97 | 141 | Myocardial Infarction |
| R. Eskandarian(20) | 2004 | Semnan | 23 | 23 | Cardiac Syndrome X |
| M.A. Bahar(21) | 2004 | Tehran | 131 | 130 | Coronary Heart Disease |
| R. Eskandarian(22) | 2006 | Semnan | 40 | 40 | Cardiac Syndrome X |
| A. Amrai(23) | 2006 | Tehran | 82 | 82 | Coronary Heart Disease |
| F. Raygan(24) | 2006 | Kashan | 50 | 50 | Myocardial Infarction |
| A.H. Faghihi(25) | 2007 | Tehran | 131 | 130 | Coronary Heart Disease |
| A. Pourya(26) | 2007 | Kermanshah | 30 | 30 | Coronary Heart Disease |
| H. Bazazi(27) | 2008 | Gorgan | 109 | 85 | Coronary Heart Disease |
| N. Sarrafzade(28) | 2008 | Isfahan | 57 | 44 | Coronary Heart Disease |
| S.M. Mohammadzadeh.(29) | 2009 | Urmia | 54 | 168 | Cardiac Syndrome X |
| Y. Nozari.(30) | 2009 | Tehran | 70 | 60 | Coronary Heart Disease |
| H. Bazazi(31) | 2009 | Gorgan | 70 | 70 | Myocardial Infarction |
| S. Davoudi(32) | 2010 | Tehran | 69 | 84 | Coronary Heart Disease |
| H. Mirzababaei(33) | 2010 | Tehran | 288 | 294 | Coronary Heart Disease |
| A. Jafarzadeh.(34) | 2010 | Rafsanjan | 60 | 60 | Myocardial Infarction |
| Z. Khodai.(14) | 2010 | Tehran, | 500 | 500 | Myocardial Infarction |
| M. H Khademiansari(35) | 2009 | Tabriz | 100 | 89 | Coronary Heart Disease |
| Z. Azarkar(36) | 2011 | Birjand | 73 | 78 | Myocardial Infarction |
| Y. Rasmi(37) | 2012 | Urmia | 100 | 100 | Cardiac Syndrome X |
| M. Rogha(38) | 2012 | Isfahan | 62 | 43 | Coronary Heart Disease |
| S. Sayyah(39) | 2012 | Qazvin | 40 | 40 | Coronary Heart Disease |
| N. Fouladi(40) | 2012 | Ardabil | 300 | 300 | Coronary Heart Disease |
| H. Honarmand(41) | 2012 | Rasht | 100 | 76 | Coronary Heart Disease |
| J. Vafaeimanesh(42) | 2014 | Qom | 62 | 58 | Coronary Heart Disease |
| N. Dehghan(43) | 2015 | Qazvin | 90 | 90 | Myocardial Infarction |