不同年齡層孕產婦家庭社經背景、各式昇醣指標與妊娠結果之影響分析

Abstract

本研究藉由不同年齡層與不同家庭社經背景分組，探討孕期昇醣指標與妊娠結果之關聯。合併兩世代資料，民93世代於台北市立聯合醫院婦幼院區與台大醫院進行招募，民98世代分別招募台灣北、中、南三個地區的醫院。研究工具分為基本資料問卷及飲食問卷。飲食問卷包括24小時飲食回憶(24-hour dietary recalls, 24HDR)和飲食頻率問卷(food frequency questionnaire, FFQ)。

本研究共分析336位母親及其新生兒。母親平均年齡為31歲、家庭社經分數4.8分(為中高社經)、家庭總月收入六~八萬。無論是將母親年齡分組(≦25歲、26-30歲、31-35歲、≧36歲)或是依不同家庭社經分組(低、中、中高、高社經)，年齡低的孕婦，家庭社經、總月收入較低。昇醣指標包括:飲食昇醣指數(dietary glycemic index,D_ GI)、昇醣負荷(glycemic load, GL)、相對血糖效應(relative glycemic effect, GL2)。使用24小時飲食回憶(24-hour dietary recall, 24HDR)、飲食頻率問卷(food frequency questionnaire, FFQ)、以熱量校正飲食頻率問卷(calibrated FFQ, cFFQ)，共三種不同的方法評估孕期昇醣指標。研究發現，年齡分組對於昇醣指標攝取狀況差異不大;以家庭社經分組，低社經組GL及GL2皆最高，隨著社經地位提高而呈線性下降。其中使用FFQ評估，在低社經組與高社經組達顯著差異(p<0.01) 。此外三種方法評估D_GI值在低社經組皆最低。以食物來源來探討，醣類、GL及GL2相似，主要食物供應來源為澱粉類主食、新鮮水果類、調味糖類、烘焙點心。D_GI則因不同評估方式而有差異，以24HDR評估D_GI結果與醣類、GL、GL2相似，而以FFQ評估D_GI則主要來源為肉類(及肉類混炒青菜)、澱粉類主食、海鮮(及海鮮混炒青菜)。

妊娠結果包括孕期體重增加量及新生兒體型。不同家庭社經背景、年齡層分組對於婦女孕前、孕期體重及孕期體重增加量皆無達到顯著差異。以整體來看，婦女孕期GL、GL2攝取越高，孕期體重增加量越多。並且GL及GL2其解釋力佔孕期體重增加量1.5~3%。新生兒體型的部分，不同家庭社經、總月收入與新生兒出生體型無顯著相關。以孕婦年齡來探討，孕婦年齡與新生兒體型呈正相關。其中年齡與新生兒的頭圍、胸圍達到顯著正相關 (p<0.01)。昇醣指標對於新生兒體型的影響，其中與新生兒出生身長較具相關，並且GL及GL2與新生兒出生身長呈負相關。其解釋力佔新生兒出生身長1%。

不同家庭社經背景，雖然對於營養素的攝取差異較大，家庭社經越高，孕婦年齡較高，攝取昇醣指標值越低，但較不影響新生兒體型。不同年齡層分組雖然在營養素攝取差異較小，但與新生兒體型較有相關。孕婦年齡與新生兒體型呈正相關。以整體來看，GL及GL2值攝取越高，母親孕期體重增加量越多。此外昇醣指標對於新生兒體型的影響，新生兒出生身長與GL及GL2呈負相關。因此在碳水化合物的選擇應選高纖適度的碳水化合物，維持適量的GL及GL2。In this study, the pregnant women weredivided into several subgroups by different ages and different family socioeconomic status (SES). The purpose of this study was to discuss the glycemic indicators during pregnancy and the pregnancy outcomes associated with age and SES. The data from two cohort studies were combined. The subjects for the first cohort were recruited from the Taipei Municipal Women’s and Children’s Hospital and National Taiwan University Hospital in 2004. The subjects for the second cohort were recuited, from the north, central and southern regions of the three hospitals in 2009. The methodology adopted the questions asked in basic information questionnaires and diet questionnaire. Diet questionnaires included the 24-hour dietary recall (24HDR) and the food frequency questionnaire (FFQ).

We analyzed data from 336 mothers and their newborns. Maternal average age was 31 years old, with the average family socioeconomic score of 4.8 (5 being high-intermediate socioeconomic) and the total household monthly income of NT$60,000-80,000. These data were classified into two major categories for subgroup analyses: the maternal age subgroups (≦25 years, 26-30 years, 31-35 years, ≧36 years old) and the family socioeconomic status subgroups: (low, medium, high-intermediate, high socioeconomic). The results indicated that thefamily socioeconomic status and total monthly incomeis for younger pregnant women were lower than the older pregnant women. The glycemic indicators including dietary glycemic index (D_GI), glycemic load (GL) and the relative glycemic effect (GL2) were calucated from the24-hour dietary recall (24HDR), the food-frequency questionnaire (FFQ) and thecalibrated food frequency questionnaire (cFFQ) to assess the pregnancy glycemic indicators. The results showed that there was no difference in glycemic indicators of the maternal age subgroups, while the data of family socioeconomic status subgroups indicated that low family socioeconomic status with the highest GL and GL2. In conclusion, the socioeconomic status is inversely associatedwith the GL and GL2, the data from the FFQ in the low socioeconomic subgroup and high socioeconomic group were significantly differencent (p<0.01).All the D_GI values in low family socioeconomic status subgroup were low by the three dietary methods.Our data showed that the food groups including starchy staples, fresh fruits, refined sugar, and baked snack were similar to provide carbohydrate, GL and GL2. We also found that different results for D_GI by using two kinds of assessment methods. The food groups providing D_GI are as similar as ones providing carbohydrate, GL, and GL2 by using 24HDR; while meat (meat and vegetable mixed,fried), starchy staples, seafood (seafood and vegetable mixed, fried) were the main food groups proving D_GI with FFQ method.

The gestational weight gainduring pregnancy and birth outcomes (birth weight, length, head and chest circumference)were also reported. There was no manifest difference between pre-pregnancy weight and gestational weight gain classified into different subgroups of family socioeconomic status or the maternal age. Overall, the pregnant women had higher average GL and GL2 with more gestational weight gain. GL and GL2 during pregnancy explain 1.5~3 % of variances for gestational weight gain. In terms ofbirth outcomes, thefamily socioeconomic subgroups or the total monthly income had no correlation with the birth outcomes. In terms of maternal age subgroups, there were positive correlations between maternal age and birth outcomes.With regards to the impact of the glycemic indicators on birth ourcomes, birth length was negatively correlated with GL and GL2. GL and GL2 during pregnancy explain 1 % of variances for birth length.

The results showed that family socioeconomic status was positively correlated with maternal age, but negatively correlated with glycemic indicators. There were no significant differences between birth outcomes in different family socioeconomic status. The nutrient intakes of different maternal age of pregnant women classified into the four subgroups were not significantly different, but there were related to the birth outcomes. Maternal age was positively correlated with the birth outcomes. Overall, the higher GL and GL2 pregnant women with more gestational weight gain. In terms of birth outcomes, birth length was negatively correlated with GL and GL2. Therefore, this study recommended pregnant women to choice high-fiber and moderate carbohydrate consumption to maintain the appropriate dietary GL and GL2 values.