Risk Factors of Breast Cancer in the Eastern Mediterranean Region: A Systematic Review and Meta-Analysis

  • Namiranian, Nasim (Department of Community Medicine. School of Medicine, Shahid Sadoughi University of Medical Sciences) ;
  • Moradi-Lakeh, Maziar (Department of Community Medicine. School of Medicine, Iran University of Medical Sciences) ;
  • Razavi-Ratki, Seid Kazem (Department of Nuclear medicine. Shahid Sadoughi University of Medical Sciences) ;
  • Doayie, Mahdyie (Ministry of Health and Medical Education) ;
  • Nojomi, Marzieh (Department of Community Medicine. School of Medicine, Iran University of Medical Sciences)
  • Published : 2014.11.28


Background: Identifying risk factors of breast cancer is a key point for preventive strategies to reduce the incidence. The aim of current study was to determine most important risk factors for breast cancer in the Eastern Mediterranean Region (EMR) using a systematic review. Materials and Methods: PubMed, Scopus, Web of Science till August 24, 2012 and the reference lists of all included studies were searched. Analytic studies which had reported odds ratios (OR), relative risk (RR) or required data to calculate them were included. A total of 343 studies were critically appraised and finally 30 studies were meta-analyzed. Heterogeneity between the studies was assessed by $I^2$ and Cochran's Q. Egger's test was used to assess publication bias. Results: Twenty five casecontrol studies, one nested case-control and four cohort studies were included. The largest ORs were obtained for history of no live birth (2.25; 95%CI: 1.58-3.18), body mass index (BMI) more than 30 (2.21; 95%CI: 1.71-2.36), age at first pregnancy more than 30 years old (1.52; 95%CI: 1.30-1.77) and meat consumption more than three times per week (1.39; 95%CI: 1.03-1.87). The other important predictors were higher education and smoking as risk factors, physical activity and ovulatory stimulating medication as protective factors. Conclusions: The most important predictors of breast cancer in EMR were history of no live birth, BMI more than 30, age at first pregnancy more than 30 years old, physical inactivity and smoking. Almost all these risk factors are consistent with known risk factors for this cancer in other parts of the world.


Supported by : Iran University of Medical Sciences


  1. Ying G, Yu BH, Xue OL, et al (2013). Tea consumption, alcohol drinking and physical activity associations with breast cancer risk among Chinese females: a systematic review and meta-analysis. Asian Pac J Cancer Prev, 14, 7543-50.
  2. Naieni KH, Ardalan A, Mahmoodi M, et al (2007). Risk factors of breast cancer in north of Iran: a case-control in Mazandaran Province. Asian Pac J Cancer Prev, 8, 395-8.
  3. NustasWP, Norton ME, Al-Masarweh I (2002). Risk factors for breast cancer in Jordanian women. J Nurs Scholarsh, 34, 19-25.
  4. Peled R, Carmil D, Siboni SO, Shoham VI, Robert B (2008). Breast cancer, psychological distress and life events among young women. BMC Cancer, 8, 245.
  5. Potashnik G, Lerner G, Genkin L, et al (1999). Fertility drugs and the risk of breast and ovarian cancers: results of a long-term follow-up study. Fertil Steril, 71, 853-9.
  6. Saadat M, Kohan L, Omidvari S(2008). Genetic polymorphisms of XRCC1 (codon 399) and susceptibility to breast cancer in Iranian women, a case-control study. Breast Cancer Res Treat, 111, 549-53.
  7. Saleh F, Reno W, Ibrahim G, et al (2008). The first pilot study on characteristics and practice patterns of Kuwaiti breast cancer patients. J Environ Pathol Toxicol Oncol, 27, 61-75.
  8. Shaham J, Gurvich R, Goral A, Czerniak A (2006). The risk of breast cancer in relation to health habits and occupational exposures. Am J Ind Med, 49, 1021-30.
  9. Shaukat U, Ismail M, Mehmood N (2013). Epidemiology, major risk factors and genetic predisposition for breast cancer in the Pakistani population. Asian Pac J Cancer Prev, 14, 5625-9.
  10. Shema L, Ore L, Shachar MB, Haj M, Linn S (2007). The association between breastfeeding and breast cancer occurrence among Israeli Jewish women: a case control study. J Cancer Res Clin Oncol, 133, 539-46.
  11. Sulaiman S, Shahril MR, Wafa SHW, et al (2014). Dietary carbohydrate, fiber and sugar and risk of breast cancer according to menopausal status in Malaysia. Asian Pac J Cancer Prev, 15, 5959-64
  12. Tehranian N, Shobeiri F, Pour F, Hagizadeh E (2011). Risk factors for breast cancer in Iranian women aged less than 40 years. Asian Pac J Cancer Prev, 11, 1723-5.
  13. Toleutay U, Reznik V, Kalmatayeva Z, Smigelskas K (2013). Risk factors of breast cancer in Kyzylorda oblast of Kazakhstan: A case-control study. Asian Pac J Cancer Prev, 14, 5961-64
  14. Wafa M, Bilal A, Ijaz J, et al (2014). Breast cancer: major risk factors and recent developments in treatment. Asian Pac J Cancer Prev, 15, 3353-8.
  15. Wells G (2000). The Newcastle-Ottawa Scale (NOS) for assessing the quality of nonrandomized studies in meta-analyses; Availablefrom:
  16. Wayne W. LaMorte (2006). Epidemiology/biostatistics tools.
  17. Yang L, Parkin DM, Ferlay J, Li L, Chen Y (2005). Estimates of cancer incidence in China for 2000 and projections for 2005. Cancer Epidemiol Biomarkers Prev, 14, 243-50.
  18. Yavari P, Mosavizadeh M, Sadrol-Hefazi B, Mehrabi Y (2005). Reproductive characteristics and the risk of breast cancer-a case-control study in Iran. Asian Pac J Cancer Prev, 6, 370-5.
  19. Harirchi I, Kolahdoozan S, Karbakhsh M, et al (2012). Twenty years of breast cancer in Iran: down staging without a formal screening program. Ann Oncol, 22, 93-7.
  20. Hajian-Tilaki KO, Ahangar T K(2011). Reproductive factors associated with breast cancer risk in northern Iran. Med Oncol, 28, 441-6.
  21. Henquin N, Trostler N, Horn Y (1994). Nutritional risk factors and breast cancer in Jewish and Arab women. Cancer Nurs, 17, 326-33.
  22. Ilic M, Vlajinac H, Marinkovic J (2013). Cigarette smoking and breast cancer: a case-control study in Serbia. Asian Pac J Cancer Prev, 14, 6643-47.
  23. International Agency for Research on Cancer (2004). IARC Monographs on the evaluation of carcinogenic risks to humans. tobacco smoke and involuntary smoking. IARC, 83.
  24. Javed S, Ali M, Sadia S, et al (2011). Combined effect of menopause age and genotype on occurrence of breast cancer risk in Pakistani population. Maturitas, 69, 377-82.
  25. Jemal A, Bray F, Center MM, et al (2011). Global Cancer Statistics. Cancer J Clin, 61, 69-90
  26. Katz D, Paltiel O, Peretz T, et al (2008). Beginning IVF treatments after age 30 increases the risk of breast cancer: results of a case-control study. Breast J, 14, 517-22.
  27. Key J, Hodgson S, Omar RZ, et al (2006). Meta-analysis of studies of alcohol and breast cancer with consideration of the methodological issues. Cancer Causes Control, 17, 759-70.
  28. Kloog I, Portnov B A, Rennert H S, Haim A (2011). Does the modern urbanized sleeping habitat pose a breast cancer risk?. Chronobiol Int, 28, 76-80
  29. Kruk J (2014). Association between vegetable, fruit and carbohydrate intake and breast cancer risk in relation to physical activity. Asian Pac J Cancer Prev, 15, 4429-36.
  30. Lerner G, Boker KL, Blumstein T, et al (2006). Infertility, ovulation induction treatments and the incidence of breast cancer - a historical prospective cohort of Israeli women. Breast Cancer Res Treat, 100, 201-12.
  31. Mahouri K, Dehghani MZ, Zare S (2007). Breast cancer risk factors in south of Islamic Republic of Iran: a case-control study. East Mediterr Health J, 13, 1265-73.
  32. Majid R, Mohammed H, Saeed H, et al (2009). Breast cancer in Kurdish women of northern Iraq: incidence, clinical stage, and case control analysis of parity and family risk. BMC Womens Health, 9, 33.
  33. Maziak W, Ward KD, Afifisoweid RA, Eissenberg T (2004). Tobacco smoking using a waterpipe: a re-emerging strain in a global epidemic. Tob Control, 13, 327-33.
  34. Minatoya M, Kutomi G, Asakura S, et al (2013). Equol, adiponectin, insulin levels and risk of breast cancer. Asian Pac J Cancer Prev, 14, 2191-9.
  35. Montazeri A, Sadighi J, Farzadi F, et al (2008). Weight, height, body mass index and risk of breast cancer in postmenopausal women: a case-control study. BMC Cancer, 8, 278.
  36. Ahmad S, Mahmood H, Kanwal S, et al (2009). Relationship of age at first live birth, parity and duration of breast feeding with non familial breast cancer in Pakistani women. a study of the cancer research group Pakistan . Cancer Res, 69, 616.
  37. Abdulbari B, Ayoubi H R, Ali A I, Al-Kubaisi A, Al-Sulaiti H (2010). Does consanguinity lead to decreased incidence of breast cancer?. Cancer Epidemiol, 34, 413-8.
  38. Aboudaoud K T (1971). Cancer of the breast and breast-feeding. Study of 279 parous women and matched controls. Cancer, 28, 781-4.<781::AID-CNCR2820280337>3.0.CO;2-B
  39. Alothaimeen A, Ezzat A, Mohamed G, Muammar T, Al-Madouj A(2004). Dietary fat and breast cancer in Saudi Arabia: a case-control study. East Mediterr Health J, 10, 879-86.
  40. Awatef M, Olfa G, Imed H, et al (2010). Breastfeeding reduces breast cancer risk: a case-control study in Tunisia. Cancer Causes Control, 21, 393-7.
  41. Bidgoli SA, Azarshab H (2014). Role of vitamin D deficiency and lack of sun exposure in the incidence of premenopausal breast cancer: a case control study in Sabzevar, Iran. Asian Pac J Cancer Prev, 15, 3391-6.
  42. Bidgoli SA, Eftekhari T, Sadeghipour R(2011). Role of xenoestrogens and endogenous sources of estrogens on the occurrence of premenopausal breast cancer in Iran. Asian Pac J Cancer Prev, 12, 2425-30.
  43. Breast cancer risk factors. Available at: Access at 2012-05-14.
  44. Calderon MR, Friedlander Y, Yanetz R, et al (2009). Cancer risk after exposure to treatments for ovulation induction. Am J Epidemiol, 169, 365-75.
  45. Collaborative group on Hormonal Factors in Breast cancer (2002). Alcohol, tobacco and breast cancer-collaborative reanalysis of individual data from 53 epidemiological studies, including 58 515 women with breast cancer and 95 067 women without the disease. Br J Cancer, 87, 1234-45.
  46. Das S, Sen S, Mukherjee A, et al (2012). Risk factors of breast cancer among women in eastern India: A tertiary hospital based case control study. Asian Pac J Cancer Prev, 13, 4979-81.
  47. Ellison RC, Zhang Y, McLennan CE, Rothman KJ (2001). Exploring the relation of alcohol consumption to risk of breast cancer. Am J Epidemiol, 154, 740-7.
  48. Faheem M, Khurram M, Jafri I, Mehmood A, et al(2007). Risk factors for breast cancer in patients treated at NORI Hospital, Islamabad. J Pak Med Assoc, 57, 242-5.
  49. Fakri S, Al-Azzawi A, Al-Tawil N (2006). Antiperspirant use as a risk factor for breast cancer in Iraq. East Mediterr Health J, 12, 478-82.
  50. Ghiasvand R, Maram E S, Tahmasebi S, Tabatabaee S H R(2011). Risk factors for breast cancer among young women in Southern Iran. Int J Cancer, 129, 1443-9.
  51. Gilani G M, Kamal S(2004). Risk factors for breast cancer in Pakistani women aged less than 45 years. Ann Hum Biol, 31, 398-407.
  52. Habibzadeh F (2012). The Lancet Middle East Edition. 379:1.

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