Breast cancer in women with previous gestational diabetes: a nationwide register-based cohort study

Breast Cancer Research

Table 3 Risk of breast cancer according to GDM history and subsequent diabetes development

	Crude HR (95% CI)	Adjusted HR (95% CI)^a
Breast cancer
No GDM and no diabetes	1 (reference)	1 (reference)
GDM and no diabetes	1.03 (0.87–1.22)	0.99 (0.83–1.17)
No GDM and then diabetes	1.03 (0.86–1.24)	1.05 (0.88–1.27)
GDM and then diabetes	0.89 (0.64–1.22)	0.88 (0.64–1.21)
Premenopausal breast cancer^b
No GDM and no diabetes	1 (reference)	1 (reference)
GDM and no diabetes	1.05 (0.87–1.26)	1.01 (0.84–1.22)
No GDM and then diabetes	0.93 (0.74–1.17)	0.97 (0.77–1.22)
GDM and then diabetes	0.89 (0.62–1.28)	0.91 (0.63–1.31)
Postmenopausal breast cancer^c
No GDM and no diabetes	1 (reference)	1 (reference)
GDM and no diabetes	0.93 (0.60–1.44)	0.92 (0.59–1.43)
No GDM and then diabetes	1.29 (0.94–1.76)	1.10 (0.80–1.52)
GDM and then diabetes	0.87 (0.45–1.68)	0.75 (0.39–1.46)

Abbreviations: GDM, gestational diabetes mellitus; HR, hazard ratio
^a Adjusted for age at index pregnancy, parity, preexisting hypertension, preexisting comorbidity, ethnicity, marital status, income, education, occupation, and calendar year of delivery
^b Age at diagnosis < 50 years
^c Age at diagnosis ≥ 50 years

ISSN: 1465-542X