Changes in cortical volumetric bone mineral density and thickness, and trabecular thickness in lactating women postpartum

CONTEXT

Lactation is associated with decreased areal bone mineral density (aBMD). Replenishment occurs especially after ceased lactation. Changes in volumetric bone mineral density (vBMD), microstructure, and dimensional parameters are unknown and may clarify the role of lactation for skeletal health. OBJECTIVE AND MAIN OUTCOMES: The objective of the study was to test the hypothesis that lactation is associated with changes in aBMD, vBMD, microstructure, and dimensional parameters.

DESIGN

At baseline (0.5 mo after delivery) and 4, 12, and 18 months thereafter, bone was assessed using dual-energy x-ray absorptiometry and high-resolution peripheral quantitative computed tomography.

PARTICIPANTS AND SETTING

Eighty-one fair-skinned postpartum women and 21 controls aged 25-40 years were recruited. The completion ratio was 73%. Postpartum women were categorized depending on duration of lactation: 0-3.9, 4-8.9, and 9 months or longer.

RESULTS

During the first 4 months, aBMD decreased at several sites (geometric mean ± SE; -0.73% ± 0.21% to -3.98% ± 0.76%) in women lactating at least 4 months. During the same time, cortical vBMD at the ultradistal tibia decreased in women lactating 4-8.9 months (-0.26% ± 0.08%) and 9 months or longer (-0.49% ± 0.10%). At 12 months postpartum, cortical thickness (≥ 9 mo, -2.48% ± 0.41%) and trabecular thickness (4-8.9 mo, -2.14% ± 0.92%; ≥ 9 mo, -2.56% ± 1.21%) also were lower than baseline. No decreases were found in women lactating less than 4 months or in controls in these parameters. At 18 months postpartum, both cortical vBMD (≥ 9 mo, -0.77% ± 0.17%) and trabecular thickness (4-8.9 mo, -2.25% ± 1.25%; ≥ 9 mo, -3.21% ± 1.41%) were lower in women with long lactation.

CONCLUSIONS

Decreases in cortical vBMD, thickness, and trabecular thickness at the ultradistal tibia were found in women lactating 4 months or longer. Longer follow-up is needed to confirm whether women with extended lactation recover fully or whether the changes could potentially lead to an increased risk of fracture in later life.

Changes in food choice during a successful weight loss trial in overweight and obese postpartum women

OBJECTIVE

To examine changes in intake across food groups during a weight loss trial that produced significant and sustainable weight loss in lactating women receiving dietary treatment.

METHODS

At 10-14 wk postpartum, 61 overweight and obese lactating Swedish women were randomized to a 12-wk dietary (D), exercise (E), combined (DE), or control (C) treatment. Food intake was assessed by 4-d weighed diet records which were used to examine changes in intake across seven food groups from baseline to 12 wk and 1 y after randomization. Differences in changes in food choice between women receiving dietary treatment (D+DE) and no dietary treatment (E+C) were examined using multivariate linear regression.

RESULTS

At baseline, sweets and salty snacks contributed to 21±10 percent of total energy intake (E%). During the intervention period, women receiving dietary treatment reduced their E% from sweets and salty snacks and caloric drinks and increased their E% from vegetables more than did women not receiving dietary treatment (all P < 0.010). At 1 y, the increased E% from vegetables was maintained significantly higher among women receiving dietary treatment (P = 0.002).

CONCLUSIONS

Lactating women receiving dietary treatment achieved sustainable weight loss through changes in food choice in line with current dietary guidelines.

Fruit and vegetable intake and cause-specific mortality in the EPIC study

Consumption of fruits and vegetables is associated with a lower overall mortality. The aim of this study was to identify causes of death through which this association is established. More than 450,000 participants from the European Prospective Investigation into Cancer and Nutrition study were included, of which 25,682 were reported deceased after 13 years of follow-up. Information on lifestyle, diet and vital status was collected through questionnaires and population registries. Hazard ratios (HR) with 95% confidence intervals (95% CI) for death from specific causes were calculated from Cox regression models, adjusted for potential confounders. Participants reporting consumption of more than 569 g/day of fruits and vegetables had lower risks of death from diseases of the circulatory (HR for upper fourth 0.85, 95% CI 0.77-0.93), respiratory (HR for upper fourth 0.73, 95% CI 0.59-0.91) and digestive system (HR for upper fourth 0.60, 95% CI 0.46-0.79) when compared with participants consuming less than 249 g/day. In contrast, a positive association with death from diseases of the nervous system was observed. Inverse associations were generally observed for vegetable, but not for fruit consumption. Associations were more pronounced for raw vegetable consumption, when compared with cooked vegetable consumption. Raw vegetable consumption was additionally inversely associated with death from neoplasms and mental and behavioral disorders. The lower risk of death associated with a higher consumption of fruits and vegetables may be derived from inverse associations with diseases of the circulatory, respiratory and digestive system, and may depend on the preparation of vegetables and lifestyle factors.

An incident case-referent study on plasma enterolactone and breast cancer risk

OBJECTIVE

Using a nested case-referent design, we evaluated the relationship between plasma levels of the lignan enterolactone and the risk of developing breast cancer.

METHODS

248 cases and 492 referents were selected from three population-based cohorts in northern Sweden. Blood samples were donated at enrollment. All blood samples were stored at -80 degrees C. Cases and referents were matched for age, date of blood sample and sampling centre. Breast cancer cases were identified through the regional and national cancer registries.

RESULTS

Plasma enterolactone was lower among smokers in all cohorts and in subjects with BMI < 23 and BMI > 28 in one of the cohorts. Low plasma concentrations of enterolactone, below the 12.5(th) percentile (mean plasma enterolactone 2.9 nmol/l), were associated with an increased risk of breast cancer. Also, high values of plasma enterolactone, above the 87.5(th) percentile (mean plasma enterolactone 58.2 nmol/l) were significantly associated with an increased breast cancer risk among women from two cohorts with only incident cases and a higher number of pre-menopausal women. High plasma enterolactone concentrations among older women from a mammary screening project with mostly prevalent cases were associated with a non-significant slightly reduced breast cancer risk.

CONCLUSION

Very low plasma concentrations of enterolactone were associated with an increased breast cancer risk in all three cohorts. In two of the cohorts, with only incident cases, very high plasma concentrations were also associated with an increased breast cancer risk. In the third cohort with mainly screen-detected cases from a mammary screening program, high plasma enterolactone concentrations were associated with a weak decreased breast cancer risk.

Breast-feeding in relation to weight retention up to 36 months postpartum in the Norwegian Mother and Child Cohort Study: modification by socio-economic status?

OBJECTIVE

We investigated the association between full breast-feeding up to 6 months as well as partial breast-feeding after 6 months and maternal weight retention at 6, 18 and 36 months after delivery in the Norwegian Mother and Child Cohort Study (MoBa), conducted by the Norwegian Institute of Public Health.

DESIGN

Cohort study. Information on exposure and outcome was collected by questionnaire.

SETTING

Norway.

SUBJECTS

Women at 6 months (n 49 676), 18 months (n 27 187) and 36 months (n 17 343) postpartum.

RESULTS

Longer duration of full breast-feeding as well as partial breast-feeding was significantly related to lower weight retention at 6 months. At 18 months full breast-feeding (0-6 months) and partial breast-feeding for 12-18 months were significantly related to lower weight retention. At 36 months only full breast-feeding (0-6 months) was significantly related to lower weight retention. For each additional month of full breast-feeding, maternal weight was lowered by 0·50 kg/month at 6 months, 0·10 kg/month at 18 months and 0·14 kg/month at 36 months (adjusted for pre-pregnant BMI, pregnancy weight gain, age and parity). Partial breast-feeding resulted in 0·25 kg/month lower maternal weight at 6 months. Interactions were found between household income and full breast-feeding in relation to weight retention at 6, 18 and 36 months, indicating most benefit among women with low income.

CONCLUSIONS

The present study supports the hypothesis that full breast-feeding contributes to lower postpartum weight retention and shows that the effect is maintained for as long as 3 years postpartum.

Associations of pre-pregnancy body mass index and gestational weight gain with pregnancy outcome and postpartum weight retention: a prospective observational cohort study

Background

Excessive gestational weight gain (GWG) is associated with pregnancy complications, and Norwegian Health Authorities have adopted the GWG recommendations of the US Institute of Medicine and National Research Council (IOM). The aim of this study was to evaluate if a GWG outside the IOM recommendation in a Norwegian population is associated with increased risk of pregnancy complications like hypertension, low and high birth weight, preeclampsia, emergency caesarean delivery, and maternal post-partum weight retention (PPWR) at 6 and 18 months.

Methods

This study was performed in 56 101 pregnant women included in the prospective national Norwegian Mother and Child Cohort Study (MoBa) in the years 1999 to 2008. Women who delivered a singleton live born child during gestational week 37 to 42 were included. Maternal prepregnant and postpartum weight was collected from questionnaires at 17^th week of gestation and 6 and 18 months postpartum.

Results

A weight gain less than the IOM recommendations (GWG < IOM rec.) increased the risk for giving birth to a low weight baby among normal weight nulliparous women. A weight gain higher than the IOM recommendations (GWG > IOM rec.) significantly increased the risk of pregnancy hypertension, a high birth weight baby, preeclampsia and emergency cesarean delivery in both nulliparous and parous normal weight women. Similar results were found for overweight women except for no increased risk for gestational hypertension in parous women with GWG > IOM rec. Seventy-four percent of the overweight nulliparous women and 66% of the obese women had a GWG > IOM rec. A GWG > IOM rec. resulted in increased risk of PPWR > 2 kg in all weight classes, but most women attained their prepregnant weight class by 18 months post-partum.

Conclusions

For prepregnant normal weight and overweight women a GWG > IOM rec. increased the risk for unfavorable birth outcomes in both nulliparous and parous women. A GWG > IOM rec. increased the risk of a PPWR > 2 kg at 18 months in all weight classes. This large study supports the Norwegian Health authorities’ recommendations for normal weight and overweight women to comply with the IOM rec.

Nutrient patterns and their food sources in an International Study Setting: report from the EPIC study

BACKGROUND

Compared to food patterns, nutrient patterns have been rarely used particularly at international level. We studied, in the context of a multi-center study with heterogeneous data, the methodological challenges regarding pattern analyses.

METHODOLOGY/PRINCIPAL FINDINGS

We identified nutrient patterns from food frequency questionnaires (FFQ) in the European Prospective Investigation into Cancer and Nutrition (EPIC) Study and used 24-hour dietary recall (24-HDR) data to validate and describe the nutrient patterns and their related food sources. Associations between lifestyle factors and the nutrient patterns were also examined. Principal component analysis (PCA) was applied on 23 nutrients derived from country-specific FFQ combining data from all EPIC centers (N = 477,312). Harmonized 24-HDRs available for a representative sample of the EPIC populations (N = 34,436) provided accurate mean group estimates of nutrients and foods by quintiles of pattern scores, presented graphically. An overall PCA combining all data captured a good proportion of the variance explained in each EPIC center. Four nutrient patterns were identified explaining 67% of the total variance: Principle component (PC) 1 was characterized by a high contribution of nutrients from plant food sources and a low contribution of nutrients from animal food sources; PC2 by a high contribution of micro-nutrients and proteins; PC3 was characterized by polyunsaturated fatty acids and vitamin D; PC4 was characterized by calcium, proteins, riboflavin, and phosphorus. The nutrients with high loadings on a particular pattern as derived from country-specific FFQ also showed high deviations in their mean EPIC intakes by quintiles of pattern scores when estimated from 24-HDR. Center and energy intake explained most of the variability in pattern scores.

CONCLUSION/SIGNIFICANCE

The use of 24-HDR enabled internal validation and facilitated the interpretation of the nutrient patterns derived from FFQs in term of food sources. These outcomes open research opportunities and perspectives of using nutrient patterns in future studies particularly at international level.

Trends in the prevalence of asthma, rhinitis, and eczema in 15 year old adolescents over an 8 year period

BACKGROUND

Trends in prevalence of asthma and allergic diseases are still controversial, and rarely studied among adolescents at midpoint of puberty.

METHODS

In 2000, a questionnaire was mailed to adolescents (n = 18,158) attending 9th grade at school and living in Västra Götaland County, Sweden. Eight years later, the same questionnaire was mailed to adolescents (n = 21,651), using identical inclusion criteria as previously. Altogether, 10,837 adolescents completed the questionnaire in 2000 and 11,754 in 2008. Differences in prevalence of physician diagnosed asthma, asthma symptoms, rhinitis, and eczema between the periods were analyzed by Chi-square test. Multiple logistic regression models were performed to test for trends in prevalence of these diseases, adjusting for potential confounders.

RESULTS

Physician diagnosed asthma and lifetime and current rhinitis were increased in 2008, while wheeze decreased (p < 0.05). Taking sex, foreign descent, body mass index, and parents' education into account, the prevalence of physician diagnosed asthma (OR 1.3 [95% CI 1.2-1.4]) and lifetime (1.7 [1.6-1.8]) and current rhinitis (1.5 [1.4-1.6]) had increased. Eczema had decreased (0.9 [0.8-0.98]). These trends were consistent in boys and girls, but more prominent in those with obesity. In physician diagnosed asthmatics, there was no change in wheeze, asthma symptoms, or asthma medication.

CONCLUSIONS

The prevalence of physician diagnosed asthma has increased over the last decade, maybe due to combinations of changes in diagnostics and increased general awareness, rather than a real increase. Results showed an increase in rhinitis and a decrease in eczema. Obesity seems to have a modifying effect, which calls for further investigation.

Diet and exercise interventions among overweight and obese lactating women: randomized trial of effects on cardiovascular risk factors

Objective

To examine the effects of Diet (D) and Exercise (E) interventions on cardiovascular fitness, waist circumference, blood lipids, glucose metabolism, inflammation markers, insulin-like growth factor 1 (IGF-1) and blood pressure in overweight and obese lactating women.

Methods

At 10–14 wk postpartum, 68 Swedish women with a self-reported pre-pregnancy BMI of 25–35 kg/m² were randomized to a 12-wk behavior modification treatment with D, E, both or control using a 2×2 factorial design. The goal of D treatment was to reduce body weight by 0.5 kg/wk, accomplished by decreasing energy intake by 500 kcal/d and monitoring weight loss through self-weighing. The goal of E treatment was to perform 4 45-min walks per wk at 60–70% of max heart-rate using a heart-rate monitor. Effects were measured 12 wk and 1 y after randomization. General Linear Modeling was used to study main and interaction effects adjusted for baseline values of dependent variable.

Results

There was a significant main effect of the D treatment, decreasing waist circumference (P = 0.001), total cholesterol (P = 0.007), LDL-cholesterol (P = 0.003) and fasting insulin (P = 0.042), at the end of the 12-wk treatment. The decreased waist circumference (P<0.001) and insulin (P = 0.024) was sustained and HDL-cholesterol increased (P = 0.005) at the 1-y follow-up. No effects from the E treatment or any interaction effects were observed.

Conclusions

Dietary behavior modification that produced sustained weight loss among overweight and obese lactating women also improved risk factors for cardiovascular disease and type 2 diabetes. This intervention may not only reduce weight-related risks with future pregnancies but also long-term risk for metabolic disease.

Trial registration

ClinicalTrials.gov NCT01343238

Adherence of pregnant women to Nordic dietary guidelines in relation to postpartum weight retention: results from the Norwegian Mother and Child Cohort Study

BACKGROUND

Pregnancy is a major life event for women and often connected with changes in diet and lifestyle and natural gestational weight gain. However, excessive weight gain during pregnancy may lead to postpartum weight retention and add to the burden of increasing obesity prevalence. Therefore, it is of interest to examine whether adherence to nutrient recommendations or food-based guidelines is associated with postpartum weight retention 6 months after birth.

METHODS

This analysis is based on data from the Norwegian Mother and Child Cohort Study (MoBa) conducted by the Norwegian Institute of Public Health. Diet during the first 4-5 months of pregnancy was assessed by a food-frequency questionnaire and maternal weight before pregnancy as well as in the postpartum period was assessed by questionnaires. Two Healthy Eating Index (HEI) scores were applied to measure compliance with either the official Norwegian food-based guidelines (HEI-NFG) or the Nordic Nutrition Recommendations (HEI-NNR) during pregnancy. The considered outcome, i.e. weight retention 6 months after birth, was modelled in two ways: continuously (in kg) and categorically (risk of substantial postpartum weight retention, i.e. ≥ 5% gain to pre-pregnancy weight). Associations between the HEI-NFG and HEI-NNR score with postpartum weight retention on the continuous scale were estimated by linear regression models. Relationships of both HEI scores with the categorical outcome variable were evaluated using logistic regression.

RESULTS

In the continuous model without adjustment for gestational weight gain (GWG), the HEI-NFG score but not the HEI-NNR score was inversely related to postpartum weight retention. However, after additional adjustment for GWG as potential intermediate the HEI-NFG score was marginally inversely and the HEI-NNR score was inversely associated with postpartum weight retention. In the categorical model, both HEI scores were inversely related with risk of substantial postpartum weight retention, independent of adjustment for GWG.

CONCLUSIONS

Higher adherence to either the official Norwegian food guidelines or possibly also to Nordic Nutrition Recommendations during pregnancy appears to be associated with lower postpartum weight retention.

Cost-utility analysis of a randomized controlled weight loss trial among lactating overweight/obese women

Background

Overweight and obesity among young, adult women are increasing problems in Sweden as in many other countries. The postpartum period may be a good opportunity to improve eating habits and lose weight in a sustainable manner. The aim was to make a cost-utility analysis of a dietary behavior modification treatment alongside usual care, compared to usual care alone, among lactating overweight and obese women.

Methods

This study was a cost-utility analysis based on a randomized controlled and longitudinal clinical diet intervention. Between 2007-2010, 68 women living in Sweden were, after baseline measurement at 8-12 weeks postpartum, randomly assigned to a 12-week dietary behavior modification treatment or control group. Inclusion criteria were: self-reported pre-pregnancy body mass index (BMI) 25-35 kg/m², non-smoker, singleton term delivery, birth weight > 2500 g, intention to breastfeed for 6 mo and no diseases (mother and child). The women in the intervention group received 1.5 hour of individual counseling at study start and 1 hour at follow-up home visits after 6 weeks of intervention, with support through cell phone text messages every two wk. Dietary intervention aimed to reduce dietary intake by 500 kcal/day. The control group received usual care. Weight results have previously been reported. Here we report on analyses carried out during 2012-2013 of cost per quality adjusted life years (QALY), based on the changes in quality of life measured by EQ-5D-3 L and SF-6D. Likelihood of cost-effectiveness was calculated using Net Monetary Benefit method.

Results

Based on conservative assumptions of no remaining effect after 1 year follow-up, the diet intervention was cost-effective. Costs per gained QALY were 8 643 – 9 758 USD. The likelihood for cost-effectiveness, considering a willingness to pay 50 000 USD for a QALY, was 87–93%.

Conclusions

The diet intervention is cost-effective.

Trial registration

ClinicalTrials.gov Identifier: NCT01343238 Registered April 27, 2011.

The regional ethics committee in Gothenburg, Sweden, approved the study on November 15, 2006.

Transformative Lifestyle Change: key to sustainable weight loss among women in a post-partum diet and exercise intervention

The increase in overweight and obesity among women is a growing concern, and reproduction is associated with persistent weight gain. We have shown that dietary behavioural modification treatment, with or without exercise, results in weight loss and maintenance of weight loss. The aim of this study was to provide an explanatory model of how overweight and obese women achieve weight loss during, and after, participating in a post-partum diet and/or exercise intervention. Using Grounded Theory, we performed and analysed 29 interviews with 21 women in a 12-week Swedish post-partum lifestyle intervention with a 9-month follow-up. Interviews were made after the intervention and at the 9-month follow-up. To overcome initial barriers to weight loss, the women needed a 'Catalytic Interaction' (CI) from the care provider. It depended on individualised, concrete, specific and useful information, and an emotional bond through joint commitment, trust and accountability. Weight loss was underpinned by gradual introduction of conventional health behaviours. However, the implementation depended on the experience of the core category process 'Transformative Lifestyle Change' (TLC). This developed through a transformative process of reciprocal changes in cognitions, emotions, body, environment, behaviours and perceived self. Women accomplishing the stages of the TLC process were successful in weight loss, in contrast to those who did not. The TLC process, dependent on initiation through CI, led to implementation and integration of recognised health behaviours, resulting in sustainable weight loss. The TLC model, including the CI construct and definition of barriers, facilitators and strategies provides an explanatory model of this process.

Energy expenditure by multisensor armband in overweight and obese lactating women validated by doubly labeled water

OBJECTIVE

To validate total energy expenditure (TEE) and activity energy expenditure (AEE) from the portable SenseWear armband (SWA) Pro 2 (TEESWA and AEESWA ; InnerView software versions SWA 5.1 and SWA 6.1) against TEE from doubly labeled water (DLW) and AEE from DLW and indirect calorimetry (TEEDLW and AEEDLW ) in overweight/obese lactating women at 10 weeks postpartum.

DESIGN AND METHODS

TEE was measured simultaneously with DLW (14 days) and SWA (first 7 days). Lactating women (n = 62), non-smoking, with a BMI > 25 kg/m(2) and wearing time SWA ≥ 90% were included.

RESULTS

Mean TEESWA5.1 was overestimated with 85 kcal/day compared to TEEDLW (P = 0.040), while mean TEESWA6.1 was underestimated with 241 kcal/day compared to TEEDLW (P < 0.001). Mean AEESWA5.1 was similar to mean AEEDLW (P = 0.818), while mean AEESWA6.1 was underestimated with 581 kcal/day compared to AEEDLW (P < 0.001). TEESWA6.1 and AEESWA6.1 were systematically underestimated at higher levels of energy expenditure and BMI while only AEESWA5.1 was systematically overestimated at higher levels of energy expenditure.

CONCLUSIONS

TEESWA5.1 and AEESWA5.1 were fairly estimated on a group level while TEESWA6.1 and AEESWA6.1 were significantly and systematically underestimated. Both SWA software versions showed large individual variation in agreement with TEEDLW and AEEDLW , limiting the validity on individual level.

Dietary intake of naturally occurring plant sterols is related to a lower risk of a first myocardial infarction in men but not in women in northern Sweden

Dietary intake of naturally occurring plant sterols is inversely related to serum cholesterol concentrations. Elevated serum cholesterol increases the risk of myocardial infarction (MI), but it is unknown if this can be reduced by dietary intake of naturally occurring plant sterols. Our aim was to investigate if a high intake of naturally occurring plant sterols is related to a lower risk of contracting a first MI. The analysis included 1005 prospective cases (219 women, 786 men) and 3148 matched referents (723 women, 2425 men), aged 29-73 y at baseline, from the population-based Northern Sweden Health and Disease Study. A food frequency questionnaire (FFQ) was completed at baseline. Absolute plant sterol intake was inversely related to the risk of a first MI in men (OR highest vs. lowest quartile = 0.70; 95% CI: 0.53, 0.85; P-trend = 0.006) but not in women. After adjustment for confounders, the estimated risk was somewhat attenuated (OR highest vs. lowest quartile = 0.71; 95% CI: 0.55, 0.92; P-trend = 0.067), suggesting that increasing sterol intake from 150 to 340 mg/d reduces the risk of a first MI by 29%. Energy-adjusted plant sterol intake was not related to the risk of a first MI in either men or women. In conclusion, the findings of this observational study show that a high absolute intake of naturally occurring plant sterols is significantly related to a lower risk of a first MI in men in northern Sweden, whereas no significant relation was seen for energy-adjusted plant sterol intake. In women, no significant associations were found. The results from this study show that intake of plant sterols may be important in prevention of MI.

Metabolic risk profile among overweight and obese lactating women in Sweden

Background

Obesity and cardiovascular diseases are increasing globally and any association between reproduction and these conditions is of concern. Unfortunately, little is known about normal levels of metabolic risk factors in women of different body mass index throughout the reproductive cycle. This study is one of the first to describe the metabolic risk profile of lactating overweight or obese women at 8–12 weeks postpartum.

Methods

During 2007–2009, 66 overweight or obese Swedish lactating women without known diseases underwent detailed measurements of their metabolic profiles, dietary intake and general health before entering a lifestyle intervention trial. Baseline measurements took place between 8–12 wk postpartum. Almost all women were exclusively breastfeeding their term infants.

Results

The women were regarded as healthy, as reflected in the absence of diagnosed diseases, their own perceptions and in normal hemoglobin, albumin and fasting plasma glucose values. Four women were diagnosed with metabolic syndrome. In these cases, underlying conditions included large waist circumference, low HDL cholesterol values, high triglyceride values and relatively high blood pressure. The metabolic profile differed between overweight and obese women; obese women had significantly higher levels of fasting insulin (p = 0.017), borderline higher HOMA values (p = 0.057) and significantly higher triglyceride values (p = 0.029), as well as larger waist and hip circumferences (p<0.001 and p<0.001). However, no significant differences between overweight and obese women were detected for LDL or total cholesterol levels. Overweight and obese women reported similar total energy and macronutrient intakes, but obese women tended to be less physically active (p = 0.081).

Conclusions

Among generally healthy lactating women, obesity as compared to overweight is associated with increased metabolic risk. This cut-off is thus important also in the early postpartum period, and obesity among these women should warrant proper health investigation. Macronutrient intake did not differ between the groups and, hence, cannot explain these differences.

Trial registration

ClinicalTrials.gov Identifier: NCT01343238

"Struggling with daily life and enduring pain": a qualitative study of the experiences of pregnant women living with pelvic girdle pain

Background

Few studies have investigated the experiences of living with pelvic girdle pain (PGP) and its impact on pregnant women’s lives. To address this gap in knowledge, this study investigates the experiences of women living with PGP during pregnancy.

Methods

A purposive sample, of nine pregnant women with diagnosed PGP, were interviewed about their experiences. Interviews were recorded, transcribed to text and analysed using a Grounded Theory approach.

Results

The core category that evolved from the analysis of experiences of living with PGP in pregnancy was “struggling with daily life and enduring pain”. Three properties addressing the actions caused by PGP were identified: i) grasping the incomprehensible; ii) balancing support and dependence and iii) managing the losses. These experiences expressed by the informants constitute a basis for the consequences of PGP: iv) enduring pain; v) being a burden; vi) calculating the risks and the experiences of the informants as vii) abdicating as a mother. Finally, the informants’ experiences of the consequences regarding the current pregnancy and any potential future pregnancies is presented in viii) paying the price and reconsidering the future. A conceptual model of the actions and consequences experienced by the pregnant informants living with PGP is presented.

Conclusions

PGP during pregnancy greatly affects the informant’s experiences of her pregnancy, her roles in relationships, and her social context. For informants with young children, PGP negatively affects the role of being a mother, a situation that further strains the experience. As the constant pain disturbs most aspects of the lives of the informants, improvements in the treatment of PGP is of importance as to increase the quality of life. This pregnancy-related condition is prevalent and must be considered a major public health concern during pregnancy.

Low-carbohydrate, high-protein diet score and risk of incident cancer; a prospective cohort study

BACKGROUND

Although carbohydrate reduction of varying degrees is a popular and controversial dietary trend, potential long-term effects for health, and cancer in specific, are largely unknown.

METHODS

We studied a previously established low-carbohydrate, high-protein (LCHP) score in relation to the incidence of cancer and specific cancer types in a population-based cohort in northern Sweden. Participants were 62,582 men and women with up to 17.8 years of follow-up (median 9.7), including 3,059 prospective cancer cases. Cox regression analyses were performed for a LCHP score based on the sum of energy-adjusted deciles of carbohydrate (descending) and protein (ascending) intake labeled 1 to 10, with higher scores representing a diet lower in carbohydrates and higher in protein. Important potential confounders were accounted for, and the role of metabolic risk profile, macronutrient quality including saturated fat intake, and adequacy of energy intake reporting was explored.

RESULTS

For the lowest to highest LCHP scores, 2 to 20, carbohydrate intakes ranged from median 60.9 to 38.9% of total energy intake. Both protein (primarily animal sources) and particularly fat (both saturated and unsaturated) intakes increased with increasing LCHP scores. LCHP score was not related to cancer risk, except for a non-dose-dependent, positive association for respiratory tract cancer that was statistically significant in men. The multivariate hazard ratio for medium (9-13) versus low (2-8) LCHP scores was 1.84 (95% confidence interval: 1.05-3.23; p-trend = 0.38). Other analyses were largely consistent with the main results, although LCHP score was associated with colorectal cancer risk inversely in women with high saturated fat intakes, and positively in men with higher LCHP scores based on vegetable protein.

CONCLUSION

These largely null results provide important information concerning the long-term safety of moderate carbohydrate reduction and consequent increases in protein and, in this cohort, especially fat intakes. In order to determine the effects of stricter carbohydrate restriction, further studies encompassing a wider range of macronutrient intakes are warranted.

Exploring dietary patterns, obesity and sources of bias: the Västerbotten Intervention Programme (VIP)

OBJECTIVE

Dietary patterns capture the overall diet and thereby provide information on how nutrients are consumed in combinations, and have been suggested to be a better method than studying single nutrients. The present study explored the relationship between dietary patterns at baseline and incidence of obesity at 10-year follow-up in women.

DESIGN

A longitudinal study using baseline measurements from 1992-1996, including food intake, medication, heredity, socio-economic status, lifestyle and measured body composition, and follow-up data collected in 2002-2006 including measured body composition.

SETTING

Data from the Västerbotten Intervention Programme (VIP) in Sweden.

SUBJECTS

A total of 6545 initially non-obese women aged 30-50 years.

RESULTS

Among women reporting plausible energy intakes, the 'Fruit and vegetables cluster' predicted the highest incidence of obesity (OR = 1·76, 95 % CI 1·11, 2·76; P = 0·015) compared with women in the other food pattern groups combined. When adjusting for metabolic factors and BMI at baseline, the risk for obesity in the 'Fruit and vegetables cluster' was attenuated to non-significance. In contrast, high intake of fruit per se was associated with a decreased risk of developing obesity (OR = 0·69, 95 % CI 0·51, 0·91; P = 0·010).

CONCLUSIONS

Dietary pattern groups identified by cluster analysis are likely to reflect characteristics in addition to diet, including lifestyle, previous and current health status and risk factors for future disease, whereas intake of fruit per se was a stable indicator and less affected by baseline characteristics. These results underscore the need for complementary methods in understanding diet-disease relationships.

Circulating carotenoids and risk of breast cancer: pooled analysis of eight prospective studies

BACKGROUND

Carotenoids, micronutrients in fruits and vegetables, may reduce breast cancer risk. Most, but not all, past studies of circulating carotenoids and breast cancer have found an inverse association with at least one carotenoid, although the specific carotenoid has varied across studies.

METHODS

We conducted a pooled analysis of eight cohort studies comprising more than 80% of the world's published prospective data on plasma or serum carotenoids and breast cancer, including 3055 case subjects and 3956 matched control subjects. To account for laboratory differences and examine population differences across studies, we recalibrated participant carotenoid levels to a common standard by reassaying 20 plasma or serum samples from each cohort together at the same laboratory. Using conditional logistic regression, adjusting for several breast cancer risk factors, we calculated relative risks (RRs) and 95% confidence intervals (CIs) using quintiles defined among the control subjects from all studies. All P values are two-sided.

RESULTS

Statistically significant inverse associations with breast cancer were observed for α-carotene (top vs bottom quintile RR = 0.87, 95% CI = 0.71 to 1.05, P(trend) = .04), β-carotene (RR = 0.83, 95% CI = 0.70 to 0.98, P(trend) = .02), lutein+zeaxanthin (RR = 0.84, 95% CI = 0.70 to 1.01, P(trend) = .05), lycopene (RR = 0.78, 95% CI = 0.62 to 0.99, P(trend) = .02), and total carotenoids (RR = 0.81, 95% CI = 0.68 to 0.96, P(trend) = .01). β-Cryptoxanthin was not statistically significantly associated with risk. Tests for heterogeneity across studies were not statistically significant. For several carotenoids, associations appeared stronger for estrogen receptor negative (ER(-)) than for ER(+) tumors (eg, β-carotene: ER(-): top vs bottom quintile RR = 0.52, 95% CI = 0.36 to 0.77, P(trend) = .001; ER(+): RR = 0.83, 95% CI = 0.66 to 1.04, P(trend) = .06; P(heterogeneity) = .01).

CONCLUSIONS

This comprehensive prospective analysis suggests women with higher circulating levels of α-carotene, β-carotene, lutein+zeaxanthin, lycopene, and total carotenoids may be at reduced risk of breast cancer.

Diet and exercise weight-loss trial in lactating overweight and obese women

BACKGROUND

Current evidence suggests a combined treatment of postpartum weight loss of diet and exercise. However, to our knowledge, neither their separate and interactive effects nor long-term outcomes have been evaluated.

OBJECTIVE

We evaluated whether a 12-wk dietary behavior modification (D) treatment to decrease energy intake, physical exercise behavior modification (E) treatment to implement moderate aerobic exercise, or combined dietary and physical exercise behavior modification (DE) treatment compared with control (usual care) (C) reduces body weight in lactating women measured at the end of treatment and at a 1-y follow-up 9 mo after treatment termination.

DESIGN

At 10-14 wk postpartum, 68 lactating Swedish women with a prepregnancy BMI (in kg/m²) of 25-35 were randomly assigned to D, E, DE, or C groups. Measurements were made at baseline, after the intervention, and again at a 1-y follow-up 9 mo later. A 2 × 2 factorial approach was used to analyze main and interaction effects of treatments.

RESULTS

Weight changes after the intervention and 1-y follow-up were -8.3 ± 4.2 and -10.2 ± 5.7 kg, respectively, in the D group; -2.4 ± 3.2 and -2.7 ± 5.9 kg, respectively, in the E group; -6.9 ± 3.0 and -7.3 ± 6.3 kg, respectively, in the DE group; and -0.8 ± 3.0 and -0.9 ± 6.6 kg, respectively, in the C group. The main effects of D treatment, but not of E treatment, on weight were significant at both times (P < 0.001).

CONCLUSIONS

Dietary treatment provided clinically relevant weight loss in lactating postpartum women, which was sustained at 9 mo after treatment. The combined treatment did not yield significant weight or body-composition changes beyond those of dietary treatment alone.

The Mediterranean diet score and mortality are inversely associated in adults living in the subarctic region

The Mediterranean diet has been widely promoted and may be associated with chronic disease prevention and a better overall health status. The aim of this study was to evaluate whether the Mediterranean diet score inversely predicted total or cause-specific mortality in a prospective population study in Northern Sweden (Västerbotten Intervention Program). The analyses were performed in 77,151 participants (whose diet was measured by means of a validated FFQ) by Cox proportional hazard models adjusted for several potential confounders. The Mediterranean diet score was inversely associated with all-cause mortality in men [HR = 0.96 (95% CI = 0.93, 0.99)] and women [HR = 0.95 (95% CI = 0.91, 0.99)], although not in obese men. In men, but not in women, the score was inversely associated with total cancer mortality [HR = 0.92 (95% CI = 0.87, 0.98)], particularly for pancreas cancer [HR = 0.82 (95% CI = 0.68, 0.99)]. Cardiovascular mortality was inversely associated with diet only in women [HR = 0.90 (95% CI = 0.82, 0.99)]. Except for alcohol [HR = 0.83 (95% CI = 0.76, 0.90)] and fruit intake [HR = 0.90 (95% CI = 0.83, 0.98)], no food item of the Mediterranean diet score independently predicted mortality. Higher scores were associated with increasing age, education, and physical activity. Moreover, healthful dietary and lifestyle-related factors additively decreased the mortality likelihood. Even in a subarctic region, increasing Mediterranean diet scores were associated with a longer life, although the protective effect of diet was of small magnitude compared with other healthful dietary and lifestyle-related factors examined.