Studies linking large pregnancy
cohorts with mortality
data can address critical questions about long-term implications of gravid health
, yet relevant US data are scant. We examined the feasibility of linking the Collaborative Perinatal Project, a large multiracial U.S. cohort study of pregnant women (n = 48,197; 1959–1966), to death records.
We abstracted essential National Death Index (NDI) (1979–2016) (n = 46,428). We performed a linkage
to the Social Security Administration Death Master File through 2016 (n = 46,450). Genealogists manually searched vital status
in 2016 for a random sample of women (n = 1,249). We conducted agreement analyses for women with abstracted data among the three sources. As proof of concept, we calculated adjusted associations between mortality
and smoking and other sociodemographic factors using Cox proportional hazards regression.
We successfully abstracted identifying information for most of the cohort (97%). National Death Index identified the greatest proportion of participants deceased (35%), followed by genealogists (31%) and Death Master File (23%). Estimates of agreement (κ [95% confidence interval]) between National Death Index and Death Master File were lower (0.52 [0.51, 0.53]) than for National Death Index and genealogist (0.66 [0.61, 0.70]). As expected, compared with nonsmokers, smoking ≥1 pack per day was associated with elevated mortality
for all vital sources and was strongest for National Death Index.
Linking this historic cohort with mortality
records was feasible and agreed reasonably on vital status
when compared with other data sources. Such linkage
enables future examination of pregnancy
conditions in relation to mortality
in a diverse U.S. cohort.