Open AccessEffect of high parity on the occurrence of prediabetes: a cohort study
Author(s) -
AlFarsi Yahya M.,
Brooks Daniel R.,
Werler Martha M.,
Cabral Howard J.,
AlShafei Mohammed A.,
Wallenburg Henk C.
Publication year - 2010
Publication title -
acta obstetricia et gynecologica scandinavica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.401
H-Index - 102
eISSN - 1600-0412
pISSN - 0001-6349
DOI - 10.3109/00016349.2010.501854
Subject(s) - prediabetes , medicine , confounding , hazard ratio , parity (physics) , proportional hazards model , cohort , population , cohort study , obstetrics , diabetes mellitus , endocrinology , type 2 diabetes , confidence interval , environmental health , physics , particle physics
Abstract Objective . To assess the effect of parity on the occurrence of prediabetes defined as an abnormal fasting plasma glucose (5.6–6.9 mmol/l), an abnormal 2‐hour oral glucose tolerance test (7.7–11.1 mmol/l), or both, before 12 weeks gestation or at least 6 weeks after delivery. Design . Retrospective cohort study. Setting . Nested on a community trial Del a ying the Develop m ent of Di a betes Me l litus type 2 (AMAL study) in Oman. Population . 532 women with a total of 3,196 pregnancies. Methods . We conducted sets of Cox proportional hazard regression analyses: crude, age‐adjusted and full models which adjusted for maternal age, education, family income and year of delivery. Main outcome measures . Hazard ratio (HR) of the effect of parity on prediabetes. Results . We enumerated 258 cases of prediabetes over 8,529 person‐years of follow up. In the crude model, high parity (≥5) pregnancies carried a higher risk of prediabetes than low parity (<5) pregnancies (HR = 3.72; 95% CI = 2.80, 4.91), and the prediabetes incidence rate increased in a dose–response fashion over multiple categories of parity. In age‐only models, the association attenuated with control of the confounding effect of maternal age (HR = 1.05; 95% CI = 0.76, 1.45). Adjusting for other confounders in the full models yielded similar results to those adjusted for maternal age only. Conclusions . The apparent effect of parity on the occurrence of prediabetes is attributable to the confounding effect of maternal age rather than to high parity.