Metabolic Syndrome Is Associated with Increased Breast Cancer Risk: A Systematic Review with Meta-Analysis

Table 2

Characteristics of studies.

Author	Year	Country	Study design	Sample size	Baseline year	Follow-up years	Age	Breast cancer cases	Menopausal status	Statistic
Agnoli et al. [43]	2010	Italy	Prospective nested case-control	792	1987–92	2003	35–69	163	Post	Rate ratios
Bosco [62]	2011	USA	Prospective cohort	49,172	1995	2007	21–69	1228	Mixed, post	Incidence rate ratios
Inoue et al. [63]	2009	Japan	Prospective cohort	18,176	1990–94	2004	40–69	120	Mixed, post	Hazard ratios
Kabat et al. [48]	2009	USA	Prospective cohort	4,888	1993–98	2005	50–79	165	Post	Hazard ratios
Osaki et al. [13]	2012	Japan	Retrospective cohort	15,386	1992–2000	2007	20+	77	Mixed, post	Hazard ratios
Ronco et al. [51]	2012	Uruguay	Case-control	912	2004	2009	<70	367	Post	Odds ratios
Rosato et al.—Cohort I [14]	2011	Italy	Case-control	3,858	1983	1994	33–86	1,988	Post	Odds ratios
Rosato et al.—Cohort II [14]	2011	Italy and Switzerland	Case-control	4,093	1991	2007	33–79	1,881	Post	Odds ratios
Russo et al. [64]	2008	Italy	Prospective cohort	Not reported	1999	2005	≥40	99	Mixed	Standardized incidence ratios
Author	Exposure assessment			Cancer identification			Confounders
Agnoli et al. [43]	Questionnaire, anthropometric measures, and fasting blood draw			Cancer registry			Age, age at menarche, age at first birth, years from menopause, number of full-term pregnancies, oral contraceptives, hormone therapy, education, cancer in first degree relatives, breastfeeding, smoking, and alcohol consumption
Bosco [62]	Questionnaire			Medical records or cancer registry data			Age, education, BMI at 18, and vigorous activity
Inoue et al. [63]	Questionnaire, anthropometric measures, and fasting and nonfasting blood draw			Self-report			Age, study area, smoking status, ethanol intake, physical activity, and total cholesterol
Kabat et al. [48]	Questionnaire, anthropometric measures, and fasting blood draw			Self-report confirmed by medical records and tumor registry abstracts			Age, education, ethnicity, BMI, oral contraceptive use, postmenopausal hormone therapy, age at menarche, age at first birth, age at menopause, alcohol, family history of breast cancer, history of breast biopsy, physical activity, energy intake, and smoking status
Osaki et al. [13]	Questionnaire, anthropometric measures, and fasting blood draw			Cancer registry			Age, smoking, and heavy drinking
Ronco et al. [51]	Questionnaire and anthropometric measures after cancer			Histologically confirmed breast cancer			Age, residence, age at menarche, parity, age at first live birth, months of breastfeeding, use of oral contraceptives, BMI, menopausal status, family history of breast cancer, and intake of beef, tomatoes, and oranges
Rosato et al. [14]	Questionnaire and waist circumference measure			Histologically confirmed breast cancer			Age, study center, study period, education, alcohol consumption, age at menarche, parity and age at first birth, age at menopause, hormone replacement therapy use, and family history of breast cancer
Russo et al. [64]	Pharmaceutical prescriptions for MS			Cancer registry			Not reported

Notes. BMI: body mass index.