Lifestyle intervention during Early Pregnancy Improves Glucose and Insulin Indices in Women at Risk for Gestational Diabetes
Lifestyle interventions (LSI) promoting healthy diets and physical activity are effective in improving insulin sensitivity among individuals with type 2 diabetes. Whether the same effect is observed among women at high risk for gestational diabetes mellitus (GDM) is unclear. To inform interventions to reduce GDM amongst high-risk groups we conducted a feasibility trial among pregnant overweight/obese low-income Black women receiving prenatal care at a large metropolitan hospital. Women were randomly assigned to receive lifestyle intervention (LSI n=28) -- monthly visits (V) focused on increasing fruit and vegetable intake reducing intakes of fat and sugars and increasing levels of moderate physical activity -- or regular care (RC n=29). Using a 75g OGTT we measured glucose at study entry (V1 gestational age (GA): 14.4±2.9 wk) and mid-pregnancy (V4 GA: 26.5±2.5 wk) with measures taken at 0 (fasting) 30 60 90 and 120 min and calculated mean±SD glucose area under the curve (gAUC). We also measured median (range) insulin at fasting and 30 min and calculated HOMA-IR. At V1 the groups were similar for gAUC (RC: 12990.5±1718.2 vs. LSI: 12285.1±2340) and fasting and 30 min insulin (30 min: 88.8 [41.4 274.8] vs. 98.0 [21.6 268.7]). gAUC and 30 min insulin both increased significantly from V1 to V4 in the RC (p≤0.05) but not LSI group. At V4 when compared with the LSI group the RC group had higher mean 30 min glucose (125.7±22.5 vs. 111.6±15.7 mg/dL p=0.05) and median 30 min insulin levels (103.0 [39.4 327.6] vs. 85.8 [37.5 200.8] uU/mL p<0.05). We subsequently observed a non-significant trend toward improved insulin sensitivity in the LSI group vs. RC group at V4 (median HOMA-IR RC: 2.7 [0.6 31.2]; LSI: 2.2 [0.7 8.3]; mean difference from V1: 1.36 vs 0.16 respectively). These results suggest that a lifestyle intervention implemented early in pregnancy in this high-risk population may improve glucose response to pregnancy-induced insulin resistance.
生活方式干预促进健康饮食和体力活动，能有效改善2型糖尿病患者胰岛素的敏感性。这种效应是否能在妊娠糖尿病高风险妇女人群中观察到尚不清楚。为明确干预方式对降低妊娠糖尿病的作用（包括高危人群），埃默里大学一课题组开展了一项可行性试验，发现孕早期施行生活方式干预能改善妊娠糖尿病妇女血糖和胰岛素风险指数。
受试人群为在大都市医院接受产前护理的超重或肥胖低收入黑人孕妇。受试者被随机分组，生活方式干预组（LSI n=28）：每月访问聚焦在水果和蔬菜摄入的增加、脂肪和糖摄入的减少以及适度体力活动的增加；常规护理组（RC n=29）。我们采用75g OGTT方法检测了实验开始（V1 胎龄（GA）：14.4±2.9 wk）、孕中期（(V4 GA: 26.5±2.5 wk）的血糖浓度，时间点分别是30、60、90、120分钟，并计算出曲线下平均血糖面积（gAUC）。同时检测了快速和30分钟的胰岛素水平，并计算了HOMA-IR（评价个体的胰岛素抵抗水平的指标）。V1胎龄，各组之间gAUC（RC: 12990.5±1718.2 vs. LSI: 12285.1±2340）、快速和30分钟胰岛素（30 min: 88.8 [41.4 274.8] vs. 98.0 [21.6 268.7]）是相似的。从V1至V4胎龄，与LSI组相比，RC组gAUC和30分钟胰岛素显著增加（p≤0.05）。在V4胎龄，与LSI组相比，RC组30分钟血糖水平（125.7±22.5 vs. 111.6±15.7 mg/dL p=0.05）和39分钟胰岛素中位数（103.0 [39.4 327.6] vs. 85.8 [37.5 200.8] uU/mL p<0.05）增高。随后我们观察到V4胎龄时两组之间胰岛素敏性的改善方面没有明显趋势（HOMA-IR中位数 RC: 2.7 [0.6 31.2]; LSI: 2.2 [0.7 8.3];与V1平均差分别为: 1.36 vs 0.16）。
以上结果提示孕早期对高危人群实施生活方式干预可能改善血糖对妊娠诱导的胰岛素抵抗的反应。
