Weight development from childhood to motherhood-embodied experiences in women with pre-pregnancy obesity: a qualitative study.

BACKGROUND: Pre-pregnancy obesity increases the risk of perinatal complications. Post-pregnancy is a time of preparation for the next pregnancy and lifestyle advice in antenatal care and postpartum follow-up is therefore recommended. However, behavioral changes are difficult to achieve, and a better understanding of pregnant women's perspectives and experiences of pre-pregnancy weight development is crucial. METHODS: We used a qualitative design and conducted semi-structured interviews with 14 women in Norway with pre-pregnancy obesity 3-12 months postpartum. Data were analyzed using thematic analysis. RESULTS: Four themes addressing women's experiences and understanding of their weight development were generated: (1) Unmet essential needs, (2) Genetic predisposition for obesity, challenging life course transitions and turning points, (3) Under a critical eye: an ever-present negative bodily awareness, and (4) Wrestling with food. Parents' inability to meet children's essential needs caused weight gain through an unbalanced diet, increased stress, and emotional eating patterns. Body criticism and a feeling of not belonging led to negative body awareness that influenced behavioral patterns and relationships. Participants reporting having had a good childhood more often described their weight development as a result of genetic predisposition, challenging life course transitions and turning points, such as illness and injuries. Nevertheless, these participants also described how eating patterns were influenced by stress and negative emotions. CONCLUSIONS: Healthcare providers should pay attention to the insider perspectives of pre-pregnancy weight development. An open and shared understanding of the root causes of these women's weight development can form a basis for more successful lifestyle guidance.

Pregnant women with obesity face increased risks of pregnancy-related complications, warranting extended monitoring of their lifestyle and weight during pregnancy. The complexity of obesity makes lifestyle changes challenging both during and beyond pregnancy. Limited research exists on understanding weight development from the perspective of pregnant women with obesity. To explore their understanding and experiences of weight development from childhood to motherhood, we conducted in-depth interviews with 14 women with a BMI ≥ 30 before their pregnancies. The interviews were preformed 3­12 months post-birth. Through thematic analysis, four themes were developed: (1) Unmet essential needs, (2) Genetic predisposition for obesity, challenging life course transitions, and turning points, (3) Under a critical eye: an ever-present negative bodily awareness, and (4) Wrestling with food. Parental neglect of their children's essential needs may result in unhealthy weight gain through an unbalanced diet and/or an urgent need to regulate negative emotions with food. Body criticism and self-perceived differences deprive children and adolescents of a carefree and accepting relationship with their bodies. While participants with a satisfactory childhood more often understood their weight in light of hereditary factors, difficult transitional phases, illness, or injuries, several of them described an eating pattern influenced by negative emotions such as stress, work pressure, and depressed mood. An open and shared understanding of the root causes of these women's weight development can form a basis for more successful lifestyle guidance.

Sexual health in long-term breast cancer survivors: a comparison with female population controls from the HUNT study.

PURPOSE: Sexual health is an important aspect of quality of life. Knowledge concerning sexual health in long-term breast cancer survivors (BCSs) is limited. This study compared sexual health in BCSs 8 years after diagnosis with similarly aged controls and examined the impact of menopausal status at diagnosis and systemic breast cancer treatments on sexual health. METHODS: Women aged 20-65 years when diagnosed with stage I-III breast cancer in 2011-2012 were identified by the Cancer Registry of Norway (n = 2803) and invited to participate in a nationwide survey. Controls were women from the Trøndelag Health Study (HUNT4). Sexual functioning and sexual enjoyment were measured by the EORTC QLQ-BR23 subscales scored from 0 to 100, and sexual discomfort by the Sexual Activity Questionnaire scored from 0 to 6. Linear regression analyses with adjustments for sociodemographic and health-related variables were performed to compare groups. Differences of ≥ 10% of range score were considered clinically significant. RESULTS: The study samples consisted of 1241 BCSs and 17,751 controls. Sexual enjoyment was poorer (B - 13.1, 95%CI - 15.0, - 11.2) and discomfort higher (B 0.9, 95%CI 0.8, 1.0) among BCSs compared to controls, and larger differences were evident between premenopausal BCSs and controls (B - 17.3, 95%CI - 19.6, - 14.9 and B 1.2, 95%CI 1.0, 1.3, respectively). BCSs treated with both endocrine- and chemotherapy had lower sexual functioning (B - 11.9, 95%CI - 13.8, - 10.1), poorer sexual enjoyment (B - 18.1, 95%CI - 20.7, - 15.5), and more sexual discomfort (B 1.4, 95% 1.3, 1.6) than controls. CONCLUSION: Sexual health impairments are more common in BCSs 8 years after diagnosis compared to similar aged population controls. During follow-up, attention to such impairments, especially among women diagnosed at premenopausal age and treated with heavy systemic treatment, is warranted.

Postpartum follow-up of women with preeclampsia: facilitators and barriers - A qualitative study.

BACKGROUND: Pregnancy causes physiological changes to the maternal organ systems that can be regarded as a cardiometabolic stress test for women. Preeclampsia, a pregnancy complication characterized by new onset of hypertension in combination with proteinuria or end-organ dysfunction, affects approximately 2-8% of pregnancies. Adverse pregnancy outcomes, including preeclampsia, have been described as a failed stress test and have been consistently linked with increased risk of cardiovascular disease later in life. The postpartum period is therefore often regarded as a window of opportunity for cardiovascular disease prevention. However, we lack knowledge about how women with preeclampsia experience current postpartum care in the Norwegian health system. The aim of this qualitative study is to uncover women's perspectives and preferences regarding postpartum follow-up. METHODS: Semi-structured telephone interviews were conducted with 17 women following a six-month lifestyle intervention study. Participants were 9-20 months postpartum, following a pregnancy complicated by preeclampsia. Data were analyzed using Malterud's systematic text condensation. RESULTS: We identified five themes, each with 2-3 subthemes, that demonstrate how women with recent preeclampsia experience postpartum follow-up: (1) fear and uncertainty (a body out of balance and facing an uncertain future), (2) a conversation on lifestyle - not really that difficult (preeclampsia as a gateway, a respectful approach, and a desire for more constructive feedback), (3) when your own health is not a priority (a new everyday life, out of focus, and lack of support), (4) motivation for lifestyle changes (an eye opener, lack of intrinsic motivation, and a helping hand), and (5) lack of structured and organized follow-up (there should be a proper system, a one-sided follow-up care, and individual variation in follow-up care). CONCLUSIONS: Findings from this study highlight the need for more systematic postpartum follow-up for women after a pregnancy complicated by preeclampsia. Further research is required to explore the potential use of standardized guidelines and routine invitations to postpartum care. Furthermore, exploring health care professionals' experiences is crucial to ensure their engagement in postpartum care after complicated pregnancies.

Preconception leisure-time physical activity and family history of stroke and myocardial infarction associate with preterm delivery: findings from a Norwegian cohort.

BACKGROUND: Preterm birth poses short and long-term health consequences for mothers and offspring including cardiovascular disease sequelae. However, studies evaluating preexisting family history of cardiovascular disease and risk factors, such as physical activity, as they relate prospectively to risk of delivering preterm are lacking. OBJECTIVES: To evaluate whether preconception past-year weekly leisure-time physical activity or a family history of stroke or of myocardical infarction prior to age 60 years in first degree relatives associated, prospectively, with preterm delivery. DESIGN: Cohort study. Baseline data from Cohort Norway (1994-2003) health surveys were linked to the Medical Birth Registry of Norway for identification of all subsequent births (1994-2012). Logistic regression models provided odds ratios (OR) and 95% confidence intervals (CI) for preterm delivery (< 37 weeks gestation); multinomial logistic regression provided OR for early preterm (< 34 weeks) and late preterm (34 through to end of 36 weeks gestation) relative to term deliveries. RESULTS: Mean (SD) length of time from baseline health survey participation to delivery was 5.6 (3.5) years. A family history of stroke associated with a 62% greater risk for late preterm deliveries (OR 1.62; CI 1.07-2.47), while a family history of myocardial infarction associated with a 66% greater risk of early preterm deliveries (OR 1.66; CI 1.11-2.49). Sensitivity analyses, removing pregnancies complicated by hypertensive disorders of pregnancy, diabetes mellitus, and stillbirth deliveries, gave similar results. Preconception vigorous physical activity of three or more hours relative to less than 1 h per week associated with increased risk of early preterm delivery (OR 1.52; 95% CI 1.01-2.30), but not late or total preterm deliveries. Light physical activity of three or more hours per week relative to less activity prior to pregnancy was not associated with early, late, or total preterm deliveries. CONCLUSIONS: Results suggest that family history of cardiovascular disease may help identify women at risk for preterm delivery. Further, research is needed regarding preconception and very early pregnancy vigorous physical activity and associated risks.

Surgery for pilonidal sinus disease in Norway: training, attitudes and preferences-a survey among Norwegian surgeons.

BACKGROUND: Pilonidal sinus disease (PSD) is frequently observed in young adults. There is no wide consensus on optimal treatment in the literature, and various procedures are used in clinical practice. The objective of this study was to assess current practice, experience, training, and attitudes towards PSD surgery among Norwegian surgeons. METHODS: An online survey on PSD surgery was created and sent to all members of the Norwegian Surgical Association. Categorical data were reported as frequencies and percentages. RESULTS: Most currently practicing Norwegian surgeons used the Bascom's cleft lift (93.2%) or minimally invasive procedures (55.4%). Midline excisions with primary closure (19.7%) or secondary healing (22.4%) were still used by some surgeons, though. Most surgeons had received training in PSD surgery supervised by a specialist, but only about half of them felt sufficiently trained. The surgeons generally performed few PSD operations per year. Many considered PSD as a condition of low surgical status and this patient group as underprioritized. CONCLUSIONS: Our findings suggest that PSD surgery in Norway has been moving away from midline excisions and towards off-midline flap procedures and minimally invasive techniques. PSD and its treatment have a low status among many Norwegian surgeons. This study calls for attention to this underprioritized group of patients and shows the need for consensus in PSD treatment such as development of national guidelines in Norway. Further investigation on training in PSD and the role of supervision is needed.

Obesity and Risk for First Ischemic Stroke Depends on Metabolic Syndrome: The HUNT Study.

Background and Purpose: Obesity is one of the most prevalent modifiable risk factors of ischemic stroke. However, it is still unclear whether obesity itself or the metabolic abnormalities due to obesity increase the risk of ischemic stroke. We therefore investigated the association between metabolic health, weight, and risk of ischemic stroke in a large prospective cohort study. Methods: In the Norwegian HUNT study (Trøndelag Health Study), we included 35 105 participants with complete information on metabolic risk factors and relevant covariates. Metabolically unhealthy state was defined as sex specific increased waist circumference in addition to 2 or more of the following criteria: hypertension, increased blood pressure, decreased high-density lipoprotein, triglycerides or glucose, or self-reported diagnosis of diabetes. We then applied Cox proportional hazard models to estimate the risk for ischemic stroke among overweight and obese metabolically healthy and unhealthy participants compared with metabolically healthy, normal weight participants. Results: A total of 1161 ischemic stroke cases occurred after an average observation time of 11.9 years. In general, metabolically unhealthy participants were at increased risk of ischemic stroke (for obese participants: hazard ratio, 1.30 [95% CI, 1.09­1.56] compared with metabolically healthy participants with a normal body mass index). Hypertension appeared to be the most important metabolic risk factor. Metabolically healthy participants with overweight or obesity were at similar risk of ischemic stroke compared with normal weight participants (hazard ratio, 1.02 [95% CI, 0.81­1.28] for participants with obesity). Obesity and overweight even over an extended period of time seems to be benign about ischemic stroke, as long as it was not associated with metabolic abnormalities. Conclusions: Obesity was not an independent ischemic stroke risk factor in this cohort, and the risk depended more on the metabolic consequences of obesity.

Normotensive preterm delivery and maternal cardiovascular risk factor trajectories across the life course: The HUNT Study, Norway.

INTRODUCTION: Preterm delivery (<37 weeks) predicts later cardiovascular disease risk in mothers, even among normotensive deliveries. However, development of subclinical cardiovascular risk before and after preterm delivery is not well understood. We sought to investigate differences in life course cardiovascular risk factor trajectories based on preterm delivery history. MATERIAL AND METHODS: The HUNT Study (1984-2008) linked with the Medical Birth Registry of Norway (1967-2012) yielded clinical measurements and pregnancy outcomes for 19 806 parous women with normotensive first deliveries. Women had up to three measurements of body mass index, waist-to-hip ratio, blood pressure, lipids, non-fasting glucose, and C-reactive protein during follow up between 21 years before to 41 years after first delivery. Using mixed effects models, we compared risk factor trajectories for women with preterm vs term/postterm first deliveries. RESULTS: Trajectories overlapped for women with preterm compared with term/postterm first deliveries for all cardiovascular risk factors examined. For instance, the mean difference in systolic blood pressure in women with preterm first deliveries compared with those with term deliveries was 0.2 mm Hg (95% CI -1.8 to 2.3) at age 20 and 1.5 mm Hg (95% CI -0.5 to 3.6) at age 60. CONCLUSIONS: A history of preterm delivery was not associated with different life course trajectories of common cardiovascular risk factors in our study population. This suggests that the robust association between preterm delivery and cardiovascular end points in Norway or similar contexts is not explained by one or more commonly measured cardiovascular risk factors. Overall, we did not find evidence for a single cardiovascular disease prevention strategy that would reduce risk among the majority of women who had preterm delivery.

Low grade albuminuria as a risk factor for subtypes of stroke - the HUNT Study in Norway.

BACKGROUND AND PURPOSE: Albuminuria is a marker for endothelial dysfunction and knowledge on its association with stroke and stroke subtypes are limited. METHODS: Corresponding data from 7261 participants of the population-based HUNT2 study (1995-1997) was linked with hospital records, identified all patients registered and diagnosed with a first-time stroke. Each diagnosis was validated by reviewal of the medical record appertaining to the individual. We then applied Cox proportional hazard models to estimate the hazard ratios (HRs) for the association between albuminuria (measured as albumin-to-creatinine-ratio, ACR) and diagnosis of stroke and stroke subtypes. RESULTS: 703 (9.7%) participants developed a first ischemic stroke during a median follow-up of 15 years. Higher albuminuria was associated with a higher rate for ischemic stroke and the risk rose steadily with increasing ACR (15% increment per unit increase in ACR concentration in mg/mmol). In the fully adjusted model, the HR for all ischemic strokes was 1.56 (95% CI 1.24-1.95) for those with an ACR ≥3 mg/mmol compared to participants with an ACR < 1 mg/mmol. Overall, increasing ACR was associated with a higher risk of all ischemic stroke subtypes. This was seen to be strongest for lacunar stroke (HR 1.75, CI 1.12-2.72, p = 0.019), and also for stroke of undetermined etiology (HR 1.53, CI 1.11-2.11, p = 0.009) and those caused by atherosclerosis in the large arteries (HR 1.51, CI 0.78-2.94, p = 0.186) than for cardio-embolic stroke (HR 1.22, CI 0.64-2.3, p = 0.518). CONCLUSIONS: Albuminuria is an important risk factor, potentially already at low grade, for ischemic stroke especially for lacunar subtype. Measuring albuminuria is both cheap and readily available. This offers the opportunity to evaluate the risk for endothelial dysfunction and thus the subsequent risk for stroke and cerebral small vessel disease.

Implementing a healthy postpartum lifestyle after gestational diabetes or preeclampsia: a qualitative study of the partner's role.

BACKGROUND: Women with preeclampsia (PE) and gestational diabetes mellitus (GDM) are at increased risk for later cardiovascular disease, and lifestyle measures are recommended to prevent subsequent disease. Partner support has been shown to be important in lifestyle modification in other diseases, but there is a lack of knowledge of partner involvement in PE and GDM. The aim of this study was to explore the partner's experiences and knowledge of gestational diseases, and how the partner wishes to contribute to lifestyle change. METHODS: A qualitative study with one focus group interview and seven in-depth individual interviews, involving eleven partners of women with a pregnancy complicated by GDM or PE. The interview data were inductively analysed using four-step systematic text condensation, supported by interdependence theory. RESULTS: Partners experienced a strong "we-feeling" and wanted to support the woman in lifestyle changes. At the same time, they felt insecure, worried, foolish and left out and they missed information from clinicians. The partners felt that their involvement was crucial to lasting lifestyle changes and expected that the clinicians would routinely invite them to discuss lifestyle change. CONCLUSIONS: Partners considered themselves an important resource for lifestyle changes for women with PE and GDM, but missed being more directly invited, informed and included in maternity care and wanted to participate in the care that followed the gestational disease. This study can help health professionals to realize that partners are an overlooked resource that can make important contributions to improve the health of the whole family if they are involved and supported by health services.

Does pregnancy complication history improve cardiovascular disease risk prediction? Findings from the HUNT study in Norway.

AIM: To evaluate whether history of pregnancy complications [pre-eclampsia, gestational hypertension, preterm delivery, or small for gestational age (SGA)] improves risk prediction for cardiovascular disease (CVD). METHODS AND RESULTS: This population-based, prospective cohort study linked data from the HUNT Study, Medical Birth Registry of Norway, validated hospital records, and Norwegian Cause of Death Registry. Using an established CVD risk prediction model (NORRISK 2), we predicted 10-year risk of CVD (non-fatal myocardial infarction, fatal coronary heart disease, and non-fatal or fatal stroke) based on established risk factors (age, systolic blood pressure, total and HDL-cholesterol, smoking, anti-hypertensives, and family history of myocardial infarction). We evaluated whether adding pregnancy complication history improved model fit, calibration, discrimination, and reclassification. Among 18 231 women who were parous, ≥40 years of age, and CVD-free at start of follow-up, 39% had any pregnancy complication history and 5% experienced a CVD event during a median follow-up of 8.2 years. While pre-eclampsia and SGA were associated with CVD in unadjusted models (HR 1.96, 95% CI 1.44-2.65 for pre-eclampsia and HR 1.46, 95% CI 1.18-1.81 for SGA), only pre-eclampsia remained associated with CVD after adjusting for established risk factors (HR 1.60, 95% CI 1.16-2.17). Adding pregnancy complication history to the established prediction model led to small improvements in discrimination (C-index difference 0.004, 95% CI 0.002-0.006) and reclassification (net reclassification improvement 0.02, 95% CI 0.002-0.05). CONCLUSION: Pre-eclampsia independently predicted CVD after controlling for established risk factors; however, adding pre-eclampsia, gestational hypertension, preterm delivery, and SGA made only small improvements to CVD prediction among this representative sample of parous Norwegian women.

Preeclampsia, gestational diabetes and later risk of cardiovascular disease: Women's experiences and motivation for lifestyle changes explored in focus group interviews.

BACKGROUND: Preeclampsia (PE) and gestational diabetes mellitus (GDM) are both associated with increased risk of future cardiovascular disease (CVD). Knowledge of the relationship between these pregnancy complications and increased CVD risk enables early prevention through lifestyle changes. This study aimed to explore women's experiences with PE and/or GDM, and their motivation and need for information and support to achieve lifestyle changes. METHODS: Systematic text condensation was used for thematic analysis of meaning and content of data from five focus group interviews with 17 women with PE and/or GDM, with a live birth between January 2015 and October 2017. RESULTS: This study provides new knowledge of how women with GDM and/or PE experience pregnancy complications in a Nordic healthcare model. It reveals the support they want and the important motivating factors for lifestyle change. We identified six themes: Trivialization of the diagnosis during pregnancy; Left to themselves to look after their own health; The need to process the shock before making lifestyle changes (severe PE); A desire for information about future disease risk and partner involvement; Practical solutions in a busy life with a little one, and; Healthcare professionals can reinforce the turning point. The women with GDM wanted healthcare professionals to motivate them to continue the lifestyle changes introduced during pregnancy. Those with severe PE felt a need for individualized care to ensure that they had processed their traumatic labor experiences before making lifestyle changes. Participants wanted their partner to be routinely involved to ensure a joint understanding of the need for lifestyle changes. Motivation for lifestyle changes in pregnancy was linked to early information and seeing concrete results. CONCLUSIONS: Women with PE and GDM have different experiences of diagnosis and treatment, which will affect the follow-up interventions to reduce future CVD risk through lifestyle change. For GDM patients, lifestyle changes in pregnancy should be reinforced and continued postpartum. Women with PE should be informed by their general practitioner after birth, and given a plan for lifestyle change. Those with severe PE will need help in processing the trauma, and stress management should be routinely offered.

Does pregnancy alter life-course lipid trajectories? Evidence from the HUNT Study in Norway.

We examined the association between pregnancy and life-course lipid trajectories. Linked data from the Nord-Trøndelag Health Study and the Medical Birth Registry of Norway yielded 19,987 parous and 1,625 nulliparous women. Using mixed-effects spline models, we estimated differences in nonfasting lipid levels from before to after first birth in parous women and between parous and nulliparous women. HDL cholesterol (HDL-C) dropped by -4.2 mg/dl (95% CI: -5.0, -3.3) from before to after first birth in adjusted models, a 7% change, and the total cholesterol (TC) to HDL-C ratio increased by 0.18 (95% CI: 0.11, 0.25), with no change in non-HDL-C or triglycerides. Changes in HDL-C and the TC/HDL-C ratio associated with pregnancy persisted for decades, leading to altered life-course lipid trajectories. For example, parous women had a lower HDL-C than nulliparous women at the age of 50 years (-1.4 mg/dl; 95% CI: -2.3, -0.4). Adverse changes in lipids were greatest after first birth, with small changes after subsequent births, and were larger in women who did not breastfeed. Findings suggest that pregnancy is associated with long-lasting adverse changes in HDL-C, potentially setting parous women on a more atherogenic trajectory than prior to pregnancy.

Correction to: The impact of parity on life course blood pressure trajectories: the HUNT study in Norway.

The article was originally published electronically on the publisher's internet portal (currently SpringerLink) on 24 January 2018 without open access.

The impact of parity on life course blood pressure trajectories: the HUNT study in Norway.

The drop in blood pressure during pregnancy may persist postpartum, but the impact of pregnancy on blood pressure across the life course is not known. In this study we examined blood pressure trajectories for women in the years preceding and following pregnancy and compared life course trajectories of blood pressure for parous and nulliparous women. We linked information on all women who participated in the population-based, longitudinal HUNT Study, Norway with pregnancy information from the Medical Birth Registry of Norway. A total of 23,438 women were included with up to 3 blood pressure measurements per woman. Blood pressure trajectories were compared using a mixed effects linear spline model. Before first pregnancy, women who later gave birth had similar mean blood pressure to women who never gave birth. Women who delivered experienced a drop after their first birth of - 3.32 mmHg (95% CI, - 3.93, - 2.71) and - 1.98 mmHg (95% CI, - 2.43, - 1.53) in systolic and diastolic blood pressure, respectively. Subsequent pregnancies were associated with smaller reductions. These pregnancy-related reductions in blood pressure led to persistent differences in mean blood pressure, and at age 50, parous women still had lower systolic (- 1.93 mmHg; 95% CI, - 3.33, - 0.53) and diastolic (- 1.36 mmHg; 95% CI, - 2.26, - 0.46) blood pressure compared to nulliparous women. The findings suggest that the first pregnancy and, to a lesser extent, successive pregnancies are associated with lasting and clinically relevant reductions in systolic and diastolic blood pressure.

Impact of eating disorders on obstetric outcomes in a large clinical sample: A comparison with the HUNT study.

OBJECTIVE: Current evidence from clinical studies suggests that having an active eating disorder (ED) during pregnancy is associated with unfavorable obstetric outcomes. However, the role of a lifetime diagnosis of ED is not fully understood. Variations in findings suggest a need for additional studies of maternal ED. This study aims to identify associations between a lifetime ED and obstetric outcomes. METHOD: Data from a hospital patient register and a population-based study (The HUNT Study) were linked to the Medical Birth Registry in Norway. Register based information of obstetric complications (preeclampsia, preterm birth, perinatal deaths, small for gestational age (SGA), large for gestational age (LGA), Caesarean sections, and 5-min Apgar score) were acquired for 532 births of women with ED and 43,657 births of non-ED women. Multivariable regression in generalized estimating equations was used to account for clusters within women as they contributed multiple births to the dataset. RESULTS: After adjusting for parity, maternal age, marital status, and year of delivery, lifetime history of anorexia nervosa was associated with increased odds of having offspring who were SGA (Odds ratio (OR) 2.7, 95% Confidence Interval (CI) 1.4-5.2). Women with a lifetime history of bulimia nervosa had higher odds of having a Caesarian section (OR 1.7 95% CI 1.1-2.5). Women with EDNOS/sub-threshold ED had a higher likelihood of having a low Apgar score at 5 min (OR 3.1, 95% CI 1.1-8.8). CONCLUSION: Our study corroborates available evidence on the associations between maternal ED and adverse obstetric outcomes.

Validity of a selection of pregnancy complications in the Medical Birth Registry of Norway.

INTRODUCTION: The validity of information on pregnancy complications in the Medical Birth Registry of Norway (MBRN) is insufficiently studied. The objective was to examine the validity of information on gestational age, birthweight, medically initiated delivery, and gestational hypertension in the MBRN. MATERIAL AND METHODS: We randomly sampled MBRN records among women who participated in the population-based HUNT Study in Nord-Trøndelag county and who gave birth during 1967-2012. We estimated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value of information in the MBRN, using hospital records as the reference standard. RESULTS: Hospital records were available for 786 out of 797 sampled MBRN records. The PPVs of preterm (<37 weeks of gestation) and early preterm birth (<34 weeks of gestation) were approximately 90%, and the PPVs of low (<2500 g) and high (>4500 g) birthweight were 100%. For medically initiated delivery, the PPV was 28% during 1967-85, but 80% during 1986-2012 and higher among preterm (76%) than among term (51%) births. For gestational hypertension, the PPV was 68%, but 88% of women labeled with gestational hypertension in the MBRN had evidence of gestational hypertension or preeclampsia in hospital records. CONCLUSIONS: The validity of information on gestational age and birthweight in the MBRN was very good. For medically initiated delivery, the validity was poor before 1985 and satisfactory thereafter. For gestational hypertension, lack of information in hospital records made the evaluation difficult, but our results suggest that most women labeled with gestational hypertension in the MBRN did have a hypertensive disorder of pregnancy.

Anthropometric factors and risk of molecular breast cancer subtypes among postmenopausal Norwegian women.

Adult height and body weight are positively associated with breast cancer risk after menopause, but few studies have investigated these factors according to molecular breast cancer subtype. A total of 18,562 postmenopausal Norwegian women who were born between 1886 and 1928 were followed up for breast cancer incidence from the time (between 1963 and 1975) height and weight were measured until 2008. Immunohistochemical and in situ hybridization techniques were used to subtype 734 incident breast cancer cases into Luminal A, Luminal B [human epidermal growth factor receptor 2 (HER2-)], Luminal B (HER2+), HER2 subtype, basal-like phenotype (BP) and five-negative phenotype (5NP). We used Cox regression analysis to assess adult height and body mass index (BMI) in relation to risk of these subtypes. We found a positive association of height with risk of Luminal A breast cancer (ptrend , 0.004), but there was no clear association of height with any other subtype. BMI was positively associated with risk of all luminal breast cancer subtypes, including Luminal A (ptrend , 0.002), Luminal B (HER2-) (ptrend , 0.02), Luminal B (HER2+) (ptrend , 0.06), and also for the HER2 subtype (ptrend , 0.04), but BMI was not associated with risk of the BP or 5NP subtypes. Nonetheless, statistical tests for heterogeneity did not provide evidence that associations of height and BMI differed across breast cancer subtypes. This study of breast cancer risk among postmenopausal women suggests that height is positively associated with risk of Luminal A breast cancer. BMI is positively associated with risk of all luminal subtypes and for the HER2 subtype.

Reproductive history and the risk of molecular breast cancer subtypes in a prospective study of Norwegian women.

PURPOSE: Breast cancer can be classified into molecular subtypes that differ in clinical characteristics and prognosis. There is some but conflicting evidence that reproductive risk factors may differ between distinct breast cancer subtypes. METHODS: We investigated associations of reproductive factors with the risk for six molecular breast cancer subtypes in a cohort of 21,532 Norwegian women who were born between 1886 and 1928 and followed up for breast cancer incidence between 1961 and 2008. We obtained stored tumor tissue from incident breast cancers and used immunohistochemistry and in situ hybridization to classify 825 invasive tumors into three luminal subtypes [Luminal A, Luminal B (HER2-) and Luminal B (HER2+)] and three non-luminal subtypes [human epidermal growth factor receptor 2 (HER2) subtype, basal-like phenotype (BP) and five negative phenotype (5NP)]. We used Cox regression to assess reproductive factors and risk for each subtype. RESULTS: We found that young age at menarche, old age at first birth and low parity were associated with increased risk for luminal breast cancer subtypes. For the HER2 subtype, we either found no association or associations in the opposite direction compared to the luminal subtypes. The BP subtype appeared to have a similar reproductive risk profile as the luminal subtypes. Breastfeeding was associated with a reduced risk for HER2 and 5NP subtypes, but was not associated with any other subtype. CONCLUSIONS: The results suggest that molecular breast cancer subtypes differ in their reproductive risk factors, but associations with non-luminal subtypes are still poorly understood and warrant further study.

The influence of diagnostic subgroups, patient- and hospital characteristics for the validity of cardiovascular diagnoses-Data from a Norwegian hospital trust.

BACKGROUND: Cardiovascular discharge diagnoses may serve as endpoints in epidemiological studies if they have a high validity. Aim was to study if diagnoses-specific characteristics like type, sub-categories, and position of cardiovascular diagnoses affected diagnostic accuracy. METHODS: Patients (n = 7,164) with a discharge diagnosis of acute myocardial infarction, heart failure or cerebrovascular disease were included. Data were presented as positive predictive values (PPV) and sensitivity. RESULTS: PPV was high (≥88%) for acute myocardial infarction (n = 2,189) (except for outpatients). For heart failure (n = 4,026) PPV was 67% overall, but higher (>99%) when etiology or echocardiography was included. For hemorrhagic (n = 257) and ischemic (n = 1,034) strokes PPVs were 87% and 80%, respectively, with sensitivity of 79% and 75%. Transient ischemic attacks (n = 926) had PPV 56%, but sensitivity 86%. Primary diagnoses showed higher validity than subsequent diagnoses and inpatient diagnoses were more valid than outpatient diagnoses (except for transient ischemic attack). The diagnoses of acute myocardial infarction and heart failure where most valid when placed at cardiology units, while ischemic stroke when discharged from an internal medicine unit. CONCLUSIONS: The diagnoses of acute myocardial infarction and stroke had excellent validity when placed during hospital stays. Similarly, heart failure diagnoses had excellent validity when echocardiography was performed before placing the diagnosis, while overall the diagnoses of heart failure and transient ischemic attack were less valid. In conclusion, the results indicate that cardiovascular diagnoses based on objective findings such as acute myocardial infarction and stroke have excellent validity and may be used as endpoints in clinical epidemiological studies with less rigid validation.

Parity, infertility, age at first birth and risk of atrial fibrillation: data from the HUNT study.

AIMS: Although parity, infertility, and age at first birth are important for later development of cardiovascular disease, research on their association with atrial fibrillation (AF) is limited. METHODS: We linked data from the population-based HUNT study, the Medical Birth Registry of Norway (MBRN) and validated medical records from local hospitals. A total of 24,015 women aged 45 years or older were followed for verified incident AF. Parity and age at first birth were retrieved from the MBRN or from self-reported questionnaires in the HUNT. History of infertility was self-reported on the HUNT questionnaire. Cox-proportional hazard models were used to calculate hazard ratios (HR) for the multivariable-adjusted associations of parity, infertility, and age at first birth with risk of AF. RESULTS: During a median follow-up of 12.8 years, 1,448 (6.0%) participants developed AF. Women with higher parity (four or more births vs. two births) were at 21% higher risk of AF (HR 1.21, 95% confidence interval (CI), 1.05-1.39). History of infertility was also associated with risk of AF (HR 1.20, 95% CI, 1.02-1.42). Among parous women, younger age at first birth (<20 years vs. 20-29 years) was associated with a 20% higher risk of AF (HR 1.20, 95% CI, 1.03-1.40). CONCLUSION: Women with four or more births, or a history of infertility, or younger age at first birth have approximately a 20% higher risk of AF among women over 45 years old.

A higher number of births and younger age at first birth are associated with a higher risk of cardiovascular disease (CVD). However, there is limited evidence on the associations between parity, age at first birth and atrial fibrillation (AF). Moreover, the association between infertility and AF remains largely unexplored. We have investigated the association between parity, infertility, age at first birth and AF in the population-based cohort from Norway (the HUNT study) among women over 45 years old. Our findings reveal that women with four or more births, or a history of infertility, or younger age at first birth have approximately a 20% higher risk of AF.