Racial/Ethnic Differences in Gestational Diabetes Prevalence and Contribution of Common Risk Factors

Background The W hite H ouse, the A merican H eart A ssociation, the A gency for H ealthcare R esearch and Q uality, and the N ational H eart, L ung and B lood I nstitute have all recently acknowledged the need to disaggregate A sian A merican subgroups to better understand this heterogeneous racial group. This study aims to assess racial/ethnic differences in relative contribution of risk factors of gestational diabetes mellitus ( GDM ) among A sian subgroups ( A sian I ndian, C hinese, F ilipino, J apanese, K orean, and V ietnamese), Hispanics, non‐Hispanic blacks, and non‐Hispanic whites. Methods Pregnant women in 2007–2012 were identified through C alifornia state birth certificate records and linked to the electronic health records in a large mixed‐payer ambulatory care organisation in N orthern C alifornia ( n  = 24 195). Relative risk and population attributable fraction ( PAF ) for specific racial/ethnic groups were calculated to assess the contributions of advanced maternal age, overweight/obesity ( C enters for D isease C ontrol and Prevention (CDC) standards and W orld H ealth O rganization ( WHO )/ A merican D iabetes A ssociation ( ADA ) body mass index cut‐offs for A sians), family history of type 2 diabetes, and foreign‐born status. Results GDM was most prevalent among A sian I ndians (19.3%). Relative risks were similar across all race/ethnic groups. Advanced maternal age had higher PAFs in non‐ H ispanic whites (22.5%) and Hispanics (22.7%). Meanwhile family history ( A sian I ndians 22.6%, C hinese 22.9%) and foreign‐borne status ( C hinese 40.2%, F ilipinos 30.2%) had higher PAFs in A sian subgroups. Overweight/obesity was the most important GDM risk factor for non‐ H ispanic whites, H ispanics, A sian I ndians, and F ilipinos when the WHO / ADA cut‐off points were applied. Advanced maternal age was the only risk factor studied that was modified by race/ethnicity, with non‐ H ispanic white and H ispanic women being more adversely affected than other racial/ethnic groups. Conclusions Overweight/obesity, advanced maternal age, family history of type 2 diabetes, and foreign‐borne status are important risk factors for GDM . The relative contributions of these risk factors differ by race/ethnicity, mainly due to differences in population prevalence of these risk factors.