Studying empirically derived dietary patterns is useful in understanding dietary practice. We classified women by their dietary patterns using latent class analysis of 66 foods and studied the association of these patterns with neural tube defects (NTDs) and congenital heart defects (CHDs) in the US National Birth Defects Prevention Study (1997–2005). Logistic regression models used data from 1,047 with an NTD, 6,641 with a CHD, and 6,123 controls that were adjusted for maternal characteristics and tested the effect modification of multivitamin supplement use. Four latent dietary patterns were identified: prudent, Western, low-calorie Western, and Mexican. Among participants who did not use supplements, those in the Mexican, Western, and low-calorie Western classes were significantly more likely (odds ratios of 1.6, 1.5, and 1.4, respectively) to have offspring born with NTDs than were those in the prudent class after adjustment of for dietary folic acid intake. In contrast, among supplement users, there was no difference in the incidence of NTDs between classes. Associations between dietary class and CHD subgroups were not modified by supplement use except for tetralogy of Fallot; among supplement users, those in the Western class were twice as likely (95% confidence interval: 1.4, 2.8) as the prudent class to have offspring with tetralogy of Fallot. Women who adhered to a Western diet were 1.2 (95% confidence interval: 1.03, 1.35) times more likely to have an infant with septal heart defect than were women who adhered to a prudent diet. A prudent dietary pattern, even with folate fortification, may decrease the risk of NTDs and some heart defects.
Latent class models are useful for classifying subjects by dietary patterns. Our goals were to use latent transition models to identify dietary patterns during pregnancy and postpartum, to estimate the prevalence of these dietary patterns, and to model transition probabilities between dietary patterns as a function of covariates. Women who were enrolled in the Pregnancy, Infection, and Nutrition Study (University of North Carolina, 2000–2005) were followed for 1 year postpartum, and their diets were assessed in the second trimester and at 3 and 12 months postpartum (n = 519, 484, and 374, respectively) by using a food frequency questionnaire. After adjusting for energy intake, parity, smoking status, race, and education, we identified 3 dietary patterns and named them “prudent,” “health conscious Western,” and “Western.” Nulliparas were 2.9 and 2.1 times more likely to be in the “prudent” class than the “health conscious Western” or the “Western” class, respectively. The 3 dietary patterns were very stable, with the “health conscious Western” class being the least stable; the probability for staying in the same class was 0.74 and 0.87 at 3 and 12 months postpartum, respectively. Breastfeeding mothers were more likely than nonbreastfeeding mothers to switch dietary pattern class (P = 0.0286). Except for breastfeeding mothers, most women did not switch dietary patterns from pregnancy to postpartum.
The adoption of US culture among immigrants has been associated with higher leisure-time physical activity and sedentary behavior. However, most research to date assesses this association using single measures of acculturation and physical activity. Our objective was to describe the cross-sectional association between acculturation and both physical activity and sedentary behavior among US Hispanic/Latino adults. Participants included Hispanic/Latinos 18-74 years living in four US locations enrolled in the Hispanic Community Health Study/Study of Latinos from 2008 to 2011. Acculturation was measured using acculturation scales (language and social), years in the US, language preference, and age at immigration. Physical activity and sedentary behavior were measured using the Global Physical Activity Questionnaire (N = 15,355) and Actical accelerometer (N = 11,954). Poisson, logistic, and linear regression were used, accounting for complex design and sampling weights. English-language preference was positively associated with self-reported leisure-time and transportation physical activity and accelerometer-assessed moderate-to-vigorous physical activity (MVPA). Social acculturation was positively associated with self-reported leisure-time and transportation physical activity and MVPA. Years in the US and age at immigration were positively associated with accelerometer-assessed MVPA. Language acculturation, years in the US, and age at immigration were associated with occupational physical activity among those who reported employment. Most acculturation measures were associated with self-reported sitting but not with accelerometer-assessed sedentary behavior. Different measures of acculturation, capturing various domains acculturation, were associated with physical activity and sedentary behavior. However, the direction of the association was dependent on the measures of acculturation physical activity/sedentary behavior, highlighting the complexity of these relationships.