Prospective investigation of folic acid supplements before and during early pregnancy and paediatric and adult cancers in the Chinese children and families cohort: a pilot study in a sample of rural and urban families

Abstract

ObjectiveTo determine the feasibility of long-term prospective follow-up and ascertainment of cancer in offspring and mothers from the 1993–1995 Chinese Community Intervention Program that provided folic acid supplements before and during early pregnancy to reduce neural tube defects.DesignFeasibility pilot study for a prospective cohort study.SettingFamilies residing during 2012–2013 in one rural and one urban county from 21 counties in 3 provinces in China included in the Community Intervention Program campaign.ParticipantsThe feasibility study targeted 560 families, including 280 from the rural and 280 from the urban county included in the large original study; about half of mothers in each group had taken and half had not taken folic acid supplements.InterventionThe planned new study is observational.Primary and secondary outcome measuresPrimary: incidence of paediatric cancers in offspring; secondary: other chronic diseases in offspring and chronic diseases in mothersResultsOnly 3.4% of pilot study families could not be found, 3.9% had moved out of the study area and 8.8% refused to participate. Interviews were completed by 82% of mothers, 79% of fathers and 83% of offspring in the 560 families. Almost all mothers and offspring who were interviewed also participated in anthropometric measurements. We found notable urban–rural differences in sociodemographic and lifestyle characteristics of the parents, but fewer differences among the offspring. In eight catchment area hospitals, we identified a broad range of paediatric cancers diagnosed during 1994–2013, although paediatric brain tumours, lymphomas and rarer cancers were likely under-represented.ConclusionsOverall, 20 years after the original Community Intervention Program, the pilot study achieved high levels of follow-up and family member interview participation, and identified substantial numbers of paediatric malignancies during 1994–2013 in catchment area hospitals. Next steps and strategies for overcoming limitations are described.

Physical Activity, Step Counts, and Grip Strength in the Chinese Children and Families Cohort Study

“…This paper reports on the PA portion of the Chinese CFCS which was conducted in two phases. In the first phase, methods were developed and tested to identify members of the original CIP cohort and recruit them for participation in the follow-up feasibility study [ 29 ]. In the second phase of this work, methods were developed and tested for a multiday assessment of diet, physical activity, UVR exposure, and other measures potentially related to health outcomes stemming from early life exposures to folic acid and to the development of cancer later in life.…”

“…In the second phase of this work, methods were developed and tested for a multiday assessment of diet, physical activity, UVR exposure, and other measures potentially related to health outcomes stemming from early life exposures to folic acid and to the development of cancer later in life. Previous papers have described the overall design of phases 1 and 2 of the Chinese CFCS [ 29 , 30 ] and UVR exposure methods and results [ 31 ]. In the present study we report on the feasibility of measurements and results for physical activity and strength.…”

“…Physical activity data collection, the subject of this paper, included handgrip dynamometry, pedometry, and a past year PAQ developed for this study. Further cancer and energy balance related variables explored in this study included: (1) UVR exposure data based on a diary and dosimetry [ 31 ] and (2) dietary data from a food frequency questionnaire and 3-day food record [ 29 , 30 ].…”

“…In 2012–2013, the CFCS, a feasibility study assessing the possibility of locating and interviewing study participants was completed on 460 CIP mothers and 462 CIP offspring [ 29 ]. Within this feasibility study, we conducted a detailed pilot study in which we tested a newly developed physical activity questionnaire (PAQ) and protocols for collecting pedometry and hand-grip dynamometer data from 93 mothers and their adolescent children carried out in two locations in China.…”

“…Within this feasibility study, we conducted a detailed pilot study in which we tested a newly developed physical activity questionnaire (PAQ) and protocols for collecting pedometry and hand-grip dynamometer data from 93 mothers and their adolescent children carried out in two locations in China. This study was designed to provide information concerning several aspects of PA and strength in urban and rural mother/offspring pairs and to explore the feasibility of multimodal PA assessment in the CFCS, a follow-up study of a small subset of the CIP [ 28 , 29 ]. In addition to establishing the feasibility of obtaining these measurements in novel settings, this study presents unusually detailed information about physical activity and strength in urban versus rural populations in China.…”