Physical activity before and during pregnancy and risk of abnormal glucose tolerance among Hispanic women

Abstract

Aim

Women diagnosed with abnormal glucose tolerance and gestational diabetes mellitus are at increased risk for subsequent type 2 diabetes, with higher risks in Hispanic women. Studies suggest that physical activity may be associated with a reduced risk of these disorders; however, studies in Hispanic women are sparse.

Methods

We prospectively evaluated this association among 1241 Hispanic participants in Proyecto Buena Salud. The Pregnancy Physical Activity Questionnaire was used to assess pre, early, and mid pregnancy physical activity. Medical records were abstracted for pregnancy outcomes.

Results

A total of 175 women (14.1%) were diagnosed with abnormal glucose tolerance and 57 women (4.6%) were diagnosed with gestational diabetes. Increasing age and body mass index were strongly and positively associated with risk of gestational diabetes. We did not observe statistically significant associations between total physical activity or meeting exercise guidelines and risk. However, after adjusting for age, BMI, gestational weight gain, and other important risk factors, women in the top quartile of moderate-intensity activity in early pregnancy had a decreased risk of abnormal glucose tolerance (odds ratio = 0.48, 95% Confidence Interval 0.27–0.88, P_trend = 0.03) as compared to those in the lowest quartile. Similarly, women with the highest levels of occupational activity in early pregnancy had a decreased risk of abnormal glucose tolerance (odds ratio = 0.48, 95% Confidence Interval 0.28–0.85, P_trend = 0.02) as compared to women who were unemployed.

Conclusion

In this Hispanic population, total physical activity and meeting exercise guidelines were not associated with risk. However, high levels of moderate-intensity and occupational activity were associated with risk reduction.

Introduction

Both gestational diabetes mellitus (GDM) and milder glucose intolerance in pregnancy identify women who are at high risk for type 2 diabetes [1], [2]; women with a history of GDM have a 7-fold risk for future type 2 diabetes [3]. Recently, studies designed to identify the diagnostic threshold between maternal hyperglycemia and adverse perinatal outcomes have observed a consistent, continuous increase in risk of adverse pregnancy outcomes over the range of maternal blood glucose levels, even at degrees not diagnostic of GDM [4].

Epidemiologic studies have been fairly consistent in showing a reduced risk of GDM for women who were active prior to pregnancy, while studies of activity during pregnancy have been somewhat less consistent [5]. However, these studies faced a number of limitations. The majority failed to use a physical activity questionnaire validated among pregnant women, limited their assessment to recreational activities only, measured activity only once during pregnancy or relied on measures of activity collected after pregnancy [6]. In addition, most studies were conducted among predominantly non-Hispanic white women [5]. During pregnancy, household and occupational activities constitute a significant proportion of physical activity [7], particularly among Hispanic women who report generally low levels of recreational physical activity during pregnancy [8].

The American College of Obstetricians and Gynecologists (ACOG) recommends that pregnant women, in the absence of contraindications, engage in 30 minutes or more of physical activity of at least moderate intensity on most, if not all, days of the week [9]. Hispanics are half as likely as non-Hispanics whites to meet ACOG guidelines [8]. This is critical as Hispanics are the largest minority group in the U.S., with the highest birth and immigration rates of any minority group [10]. Hispanics from the Caribbean islands (i.e., Puerto Ricans and Dominicans) are the 2nd largest group of Hispanics living in the U.S. [10], the fastest growing subgroup, and the largest Hispanic subgroup in the northeast U.S. [11], [12]. As compared to other Hispanics, Puerto Ricans and Dominicans experience the greatest health disparities, the highest prevalence of type 2 diabetes, and exhibit more adverse health behaviors such as poor nutrition [13], [14], [15].

Therefore, our objective was to prospectively examine the relationship between physical activity during pre, early, and mid pregnancy and risk of abnormal glucose tolerance (AGT) and GDM.