Marie-Christine Dubé

Weight Gain Measures in Women with Gestational Diabetes Mellitus

BACKGROUND Gestational diabetes mellitus (GDM) and excessive gestational weight gain have significant implications for the health of both mother and child. Our objective was to detail gestational weight gain in women in relationship to GDM. METHODS Data were collected by retrospective reviews of medical records in women who delivered between January and December 2007 at the Laval University Medical Center (Quebec, Canada). The analysis included 294 women (55 GDM and 239 controls) for whom gestational weight gain was calculated by the difference between maternal weight measured at delivery, or at the last prenatal visit (≥37th week), and prepregnancy self-reported weight. Gestational weight gain and rate of weight gain were also calculated for each trimester and until GDM screening. Gestational weight gain was compared to the 2009 recommendations by the Institute of Medicine (IOM). Women with GDM were diagnosed and treated according to the Canadian Diabetes Association guidelines. RESULTS Weight gain in the first trimester was significantly higher in GDM patients compared to controls (3.40 ± 0.42 vs. 1.87 ± 0.16 kg, p ≤ 0.01) and was above IOM recommendations, whereas weight gain in the third trimester was significantly lower in GDM patients compared to controls (4.11 ± 0.36 vs. 6.35 ± 0.18 kg, p ≤ 0.0001). Prepregnancy body mass index (BMI) and first trimester weight gain were both significant and independent predictors of GDM (odds ratio [OR] 1.11, 95% confidence interval [CI] 1.05-1.17, and OR 1.25, 95% CI 1.10-1.42, respectively). CONCLUSIONS First trimester gestational weight gain may need more clinical attention, as it has been identified as an independent and significant risk factor for GDM independent of traditional risk factors, including preconception obesity.

Circulating interleukin-6 concentrations during and after gestational diabetes mellitus.

Objective. Recent studies have shown that high interleukin‐6 (IL‐6) secretion may aggravate insulin resistance in pregnancy and participate in the pathogenesis of gestational diabetes mellitus (GDM). The aim of this study was to determine whether the presence of GDM is associated with elevated IL‐6 concentrations and whether this association remains after delivery, independent of body mass index. Design. Longitudinal study. Setting. Hospital‐based. Sample. Forty‐seven women were screened for GDM with a 75g oral glucose tolerance test at 26.1±3.7 weeks of pregnancy following the Canadian Diabetes Association guidelines (20 GDM, 27 control subjects). Main outcome measures. Interleukin‐6 levels were measured by ELISA at the time of GDM screening and two months post‐partum. Results. Interleukin‐6 concentrations were significantly higher in women with GDM compared with control women at the time of GDM screening (1.47±0.72 vs. 0.90±0.32pg/mL, p≤0.01). Similar results were obtained two months post‐partum, where IL‐6 levels remained significantly higher in women with GDM compared with control women (1.88±0.85 vs. 1.41±0.87pg/mL, p≤0.05). Interleukin‐6 concentrations were significantly correlated with the Matsuda insulin sensitivity index, measured at the two time points (r=–0.60, p≤0.01 and r=–0.34, p≤0.05). The Matsuda insulin sensitivity index was an independent and significant predictor of IL‐6 concentrations at the time of GDM screening, explaining 35.6% of the variance (p≤0.0001) in this variable. IL‐6 concentration measured at GDM screening was identified as an independent and significant predictor of post‐partum IL‐6 concentrations, explaining 28.6% of the variance (p≤0.001). Conclusions. These results show that GDM is associated with elevated IL‐6 levels independent of obesity levels, both during pregnancy and after delivery.

Androgens in the maternal and fetal circulation: association with insulin resistance.

Objective: To examine maternal insulin resistance in relationship with maternal and fetal androgen levels as well as with term placenta mRNA and protein abundance of steroidogenic enzymes implicated in androgen dynamics. Methods: The study included 20 women with gestational diabetes mellitus and 27 controls tested using a 120 min., 75 g oral glucose tolerance test. Maternal and fetal plasma concentrations of total testosterone, dihydrotestosterone (DHT) and dehydroepiandrosterone (DHEA) were measured by high-performance gas chromatography and chemical ionization mass spectrometry at 26.1 ± 3.7 weeks of pregnancy. Results: Glycemic response to oral glucose over 120 min. as well as Matsuda insulin sensitivity and HOMA insulin resistance (HOMA-IR) indices were significantly associated with maternal testosterone levels (r = 0.31, r = −0.37 and r = 0.35 respectively, p ≤ 0.05 for all). Among male offspring, a positive association between maternal and fetal testosterone levels was observed (r = 0.43, p ≤ 0.05). Testosterone levels were higher in the cord blood of newborns from insulin-resistant mothers compared to newborns from insulin-sensitive mothers (0.48 ± 0.36 nmol/L vs. 0.29 ± 0.18 nmol/L p ≤ 0.05). No difference was observed in mRNA abundance or protein expression of placental steroidogenic enzymes according to the degree of maternal insulin resistance. Conclusion: Our results demonstrate a possible association between fetal and maternal androgen concentrations in relationship with insulin resistance.

The Contribution of Visceral Adiposity and Mid-Thigh Fat-Rich Muscle to the Metabolic Profile in Postmenopausal Women

This study explored the relationship between muscle fat infiltration derived from mid‐thigh computed tomography (CT) scan, central fat distribution and insulin sensitivity in postmenopausal women. Mid‐thigh CT scans were used to measure low attenuation muscle surface (LAMS) (0–34 Hounsfield units (HU)), which represented a specific component of fat‐rich muscle. Whole‐body insulin sensitivity (M/I) was evaluated by an euglycemic‐hyperinsulinemic clamp. A group of 103 women aged 57.0 ± 4.4 years was studied. Women with higher levels of LAMS presented higher metabolic risk features, particularly elevated fasting, 2‐h plasma glucose (2hPG) concentrations and diminished M/I (P < 0.05). To further study the contribution of muscle fat infiltration and central adiposity on metabolic parameters, we divided the whole group based on the median of LAMS and visceral adipose tissue (VAT). As expected, the best metabolic profile was found in the Low‐LAMS/Low‐VAT group and the worst in the High‐LAMS/High‐VAT group. Women with Low‐LAMS/High‐VAT presented similar metabolic risks to those with High‐LAMS/High‐VAT. There was no difference between High‐LAMS/Low‐VAT and Low‐LAMS/Low‐VAT, which presents the most healthy metabolic and glycemic profiles as reflected by the lowest levels of cardiovascular disease risk variables. This suggests that High‐LAMS/Low‐VAT is also at low risk of metabolic deteriorations and that High‐LAMS, only in the presence of High‐VAT seems associated with deteriorated risks. Although increased mid‐thigh fat‐rich muscle was related to a deteriorated metabolic profile, VAT appears as a more important contributor to alterations in the metabolic profile in postmenopausal women.

Glucose or intermittent high-intensity exercise in glargine/glulisine users with T1DM.

INTRODUCTION The effects of glargine/glulisine insulin regimen on exercise blood glucose (BG) and strategies to limit exercise-induced hypoglycemia are not well documented. Intermittent high-intensity exercise has been proposed to prevent hypoglycemia, but its effect in participants with type 1 diabetes using glargine/glulisine is unknown. METHODS The study used a repeated-measures design with three randomly ordered exercise conditions. Eleven participants completed 60 min of moderate-intensity exercise at 50% VO(2peak) for all conditions. These conditions varied as follows: participants ingested 0 g of glucose preexercise (0G + MOD), 30 g of glucose preexercise (30G + MOD), or 0 g of glucose preexercise but performed brief high-intensity intervals interspersed every 2 min (0G + MOD/INT) during exercise. If BG fell <4 mmol·L(-1), a 20% dextrose solution was started to maintain BG between 4 and 5 mmol·L(-1). RESULTS Consuming 30 g of glucose before exercise (30G + MOD) resulted in a higher preexercise BG (11.7 ± 2.7 mmol·L(-1)) compared with 0 g of glucose before exercise (0G + MOD, 7.8 ± 4.0, and 0G + MOD/INT, 9.2 ± 3.5mmol·L(-1)), P < 0.05. A dextrose infusion was required in 7/11, 4/11, and 1/11 participants for 0G + MOD, 0G + MOD/INT, 30G + MOD conditions, respectively, P < 0.02. The duration and the quantity of dextrose infused were greatest in the 0G + MOD condition, moderate in the to 0G + MOD/INT condition, and minimal in the 30G + MOD condition, P < 0.01. CONCLUSION Our results suggest that both moderate-intensity exercise with a 30-g preexercise glucose beverage or interspersed with intermittent high-intensity sprints may be safe strategies to prevent hypoglycemia in glargine/glulisine users.

Nutritional strategies to prevent hypoglycemia at exercise in diabetic adolescents.

UNLABELLED Studies on nutritional strategies to prevent exercise-induced hypoglycemia in adolescents with type 1 diabetes are scarce. OBJECTIVE This study aimed to compare the effect of two food strategies on blood glucose (BG) during and after 60 min of moderate-intensity exercise. METHODS Subjects performed exercise 120 min after breakfast in three conditions: 1) standardized breakfast + preexercise placebo beverage (PL), 2) standardized breakfast + preexercise CHO beverage (8 mg of CHO·kg of body weight·min of exercise; CHO), or 3) protein-supplemented breakfast (8 mg of protein·kg of body weight·min of exercise added to the standardized breakfast) + preexercise placebo beverage (PROT). As soon as BG falls <4 mmol·L or symptomatic hypoglycemia occurred during exercise, the session was stopped and CHO tablets were provided to correct hypoglycemia. RESULTS Ten subjects (age = 14.0 ± 1.5 yr) participated in all conditions. BG decreased by 6.0 ± 1.9, 1.0 ± 3.1, and 4.6 ± 1.9 mmol·L in PL, CHO, and PROT conditions, respectively (P < 0.05). The proportion of subjects reaching hypoglycemic values or sensations of hypoglycemia was significantly different between conditions with 4/10, 1/10, and 0/10 in the PL, CHO, and PROT conditions (P < 0.05). CONCLUSIONS The preexercise CHO beverage induced the least dramatic BG decrease during exercise. The PROT breakfast induced an overall similar BG drop compared to PL, a larger BG drop compared to CHO, but a similar rate of hypoglycemia compared to CHO. Our results suggest that taking CHO supplement before unplanned exercise is still the best strategy to prevent exercise-induced hypoglycemia in an adolescent population. However, a protein supplement strategy may also have some benefits in limiting the rate of hypoglycemia during and immediately after exercise.

Sex hormone-binding globulin levels and obesity in women with gestational diabetes: relationship with infant birthweight

Our objective was to determine whether sex hormone-binding globulin (SHBG) concentrations are associated with gestational diabetes mellitus (GDM) and whether this association is independent of prepregnancy body mass index (BMI). The relationship between maternal SHBG concentrations and birthweight in the offspring was also examined. The study included 47 women (20 with GDM, 27 controls). GDM screening and fasting serum SHBG measurements were performed at 26.1 ± 3.7 weeks of pregnancy. A trend was observed for significantly lower SHBG concentrations in GDM patients (179 ± 36 vs. 195 ± 36 nmol/l, p ≤ 0.08). Prepregnancy BMI and BMI at the time of GDM screening were both correlated with SHBG concentrations (r = −0.49 and r = −0.53, respectively; p  ≤ 0.001). In multivariate regression analyses, only prepregnancy BMI or BMI at the time of GDM screening remained significant predictors of GDM risk [odds ratio (OR):1.23, 95% confidence interval (CI):1.06–1.47, p  ≤ 0.01 and OR:1.18, 95% CI:1.02–1.39, p  ≤ 0.02] while SHBG level did not. On the other hand, 10.7% of the variance in birthweight was explained by SHBG concentrations (p  ≤ 0.01) independent of the presence of GDM, parity, maternal age, maternal prepregnancy BMI, maternal height, and offspring sex. In conclusion, although SHBG concentration is not an independent predictor of GDM risk when obesity is considered, it is a significant predictor of infant birthweight independent of GDM and prepregnancy BMI.

Cord blood C‐peptide levels relate to the metabolic profile of women with and without gestational diabetes

Plasma C‐peptide reflects the insulin‐secretory activity of pancreatic β‐cells which modulates fetal growth. Cord blood C‐peptide levels were measured in women with gestational diabetes mellitus (GDM) and in women with normal glucose tolerance (NGT). Forty‐one women underwent a 75‐g oral glucose tolerance test (18 GDM, 23 NGT). Cord blood C‐peptide (p = 0.09) and glucose levels (p = 0.08) from newborns of GDM women tended to be higher than those from NGT women. In the entire group, cord blood C‐peptide correlated with maternal insulin, fasting C‐peptide, insulin sensitivity, interleukin‐6, weight and body mass index measured at screening (ρ from 0.34 to 0.48, all p < 0.05) and tended to correlate with offspring weight (ρ = 0.28, p = 0.08). Newborns of GDM women tended to have elevated cord blood C‐peptide which correlated with maternal insulin, insulin sensitivity and anthropometric measures at diagnosis and with offspring characteristics. This suggests that insulin‐secretory activity of the newborn is related to maternal metabolic parameters.

Influence of Physical Activity Participation on the Associations between Eating Behaviour Traits and Body Mass Index in Healthy Postmenopausal Women

Available data reveals inconsistent relationships between eating behaviour traits and markers of adiposity level. It is thus relevant to investigate whether other factors also need to be considered when interpreting the relationship between eating behaviour traits and adiposity. The objective of this cross-sectional study was thus to examine whether the associations between variables of the Three-Factor Eating Questionnaire (TFEQ) and adiposity are influenced by the level of physical activity participation. Information from the TFEQ and physical activity was obtained from 113 postmenopausal women (56.7 ± 4.2 years; 28.5 ± 5.9 kg/m2). BMI was compared between four groups formed on the basis of the physical activity participation and eating behaviour traits medians. In groups of women with higher physical activity participation, BMI was significantly lower in women who presented higher dietary restraint when compared to women who had lower dietary restraint (25.5 ± 0.5 versus 30.3 ± 1.7 kg/m2, P < .05). In addition, among women with lower physical activity participation, BMI was significantly lower in women presenting a lower external hunger than in those with a higher external hunger (27.5 ± 0.8 versus 32.4 ± 1.1 kg/m2, P < .001). Our results suggest that physical activity participation should also be taken into account when interpreting the relationship between adiposity and eating behaviour traits.

Impact of a Mother’s Weight History on Her Offspring

OBJECTIVE To explore the relationship between maternal lifelong body weight history and anthropometric measurements in the offspring. METHODS We studied a prospective sample of 48 pregnant women with either gestational diabetes mellitus (GDM, n = 21) or normal glucose tolerance (NGT, n = 27). Reported maternal weight at birth, 20 years of age and 30 years of age, and pre-pregnancy and maximal weight outside pregnancy were obtained by questionnaire. BMI was calculated using data from the questionnaire. Maternal anthropometric parameters were measured during pregnancy. Offspring anthropometrics were obtained at birth and eight weeks later. RESULTS Maternal weight at birth, weight or BMI at 20 years of age and at 30 years of age, and maximal weight or BMI did not differ between groups. In all women, maternal birth weight, BMI at 20 years of age, and maximal BMI correlated with newborn birth weight (ρ = 0.39, 0.37, and 0.27, respectively, P ≤ 0.05), with newborn length (ρ = 0.46, 0.32, and 0.30 respectively, P < 0.05), and with infant weight eight weeks later (ρ = 0.43, 0.30, and 0.31, respectively, P < 0.05). Reported maternal BMI at 30 years of age correlated with infant weight (ρ = 0.31) and cranial circumference (ρ = 0.33) at eight weeks of life (P < 0.05). Besides gestational age, maternal weight at screening was the most significant predictor of infant birth weight. CONCLUSION Several parameters of maternal weight history were related to offspring anthropometric measurements in early life in a sample of women with and without GDM.