Changes in eating behaviour and food choices in families ... - Nature

European Journal of Clinical Nutrition (2016) 70, 35–40 © 2016 Macmillan Publishers Limited All rights reserved 0954-3007/16 www.nature.com/ejcn

ORIGINAL ARTICLE

Changes in eating behaviour and food choices in families where the mother undergoes gastric bypass surgery for obesity M Willmer1, D Berglind1, P Tynelius1, A Ghaderi2, E Näslund3 and F Rasmussen1 BACKGROUND/OBJECTIVES: There is a lack of research exploring the effects of Roux-en-Y gastric bypass (RYGB) surgery on the patient’s family’s eating behaviour and food choices. The aim of the current study was to investigate changes in partners’ and children’s eating behaviour and food choices following maternal RYGB. SUBJECTS/METHODS: Sixty-nine women and their families were recruited from RYGB waiting lists at five Swedish surgical clinics. Data were collected during home visits 3 months before and 9 months after RYGB. Anthropometrical measures were taken, the adults completed the Three-Factor Eating Questionnaire and the children completed the Children’s Eating Attitudes Test (ChEAT). All participants also completed a short food frequency questionnaire. RESULTS: Changes in scores were analysed using paired t-tests for unadjusted estimates or linear regression models with robust variance (General Estimating Equations) in order to enable age- and sex-adjusted estimates for the children. There were no meaningful differences in the partners’ eating behaviour or food choices. The boys, but not the girls, improved their ChEAT scores, as did the overweight/obese children in comparison with the normal-weight children. The boys, unlike the girls, also decreased their intake of soft drinks, as did the normal-weight children when compared with the overweight/obese children. CONCLUSIONS: No clear-cut changes were found in partners’ eating behaviour and food choices. Eating attitudes and soft drinks intake were improved among boys but not among girls. Differing modelling behaviour may partially explain these findings, but available data did not allow us to understand the underlying mechanisms. European Journal of Clinical Nutrition (2016) 70, 35–40; doi:10.1038/ejcn.2015.136; published online 2 September 2015

INTRODUCTION For morbidly obese patients, bariatric surgery produces significant long-term weight loss and reduction in comorbidities, together with relatively low complication rates.1–3 Laparoscopic Roux-en-Y gastric bypass (RYGB) accounts for over 90% of all bariatric procedures carried out in Sweden today.3 Although there are no national Swedish post-RYGB dietary guidelines, all Swedish clinics where the surgery is performed have similar recommendations, which include eating very small, frequent and nutrient-dense meals. The local nature of these recommendations means that there is no readily available scientific reference. The patient is also advised to avoid foods that are high in sugar and/or fat, partly because these foods often cause unpleasant ‘dumping’ symptoms,4 but also because they contribute to poor weight loss or early weight regain. RYGB patients generally report increased dietary restraint and decreased uncontrolled and emotional eating (EE).5–7 Studies investigating effects of RYGB surgery on the patient’s family are few, but one such study found that partners of RYGB patients decrease their own emotional and uncontrollable eating, and that parental RYGB increases dieting awareness in their children.8 Another study, however, came to the conclusion that obese children of parents who had undergone bariatric surgery were more likely to eat at the wrong time of day and to eat two or more helpings of food when compared with obese children of obese parents who had not undergone bariatric surgery.9

Studies on non-surgical weight-loss interventions have shown a household ripple effect.10–12 It has also been shown that household availability of specific foods is an important correlate for family members’ intake.13 Mothers have been shown to have an important role in the transmission of eating behaviours to their children, and parental dieting and weight talk are associated with dieting awareness in girls as young as 8 years old.14–16 In light of these findings, the primary aim of the current study was to explore whether the eating behaviour and food choices of women treated by RYGB influence their children’s and partner’s eating behaviour and food choices. Studies investigating food choices after RYGB show that patients avoid carbonated drinks, chocolate and other energydense foods.17–19 There is almost no previous research on changes in food choices of the patient’s family. A study by Walters-Bugbee et al.7 compared food items in the homes of women who had undergone RYGB with women who were still waiting to do so and found no significant differences. As sugar-sweetened soft drinks are associated with childhood obesity, we wanted to explore whether maternal RYGB and subsequent decrease in soft drink intake would also affect the children’s consumption of sugar-sweetened soft drinks.20 The same arguments apply to energy-dense, nutrient-poor foods such as sweets and cakes.21 We were also interested in whether maternal RYGB would affect the children’s intake of fruit and vegetables. Consumption of fruit and vegetables in childhood

1 Child and Adolescent Public Health Epidemiology, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden; 2Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden and 3Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden. Correspondence: Professor F Rasmussen, Child and Adolescent Public Health Epidemiology, Department of Public Health Sciences, Karolinska Institutet, Tomtebodavägen 18A, Widerströmska huset, Stockholm 17177, Sweden. E-mail: [email protected] Received 4 December 2014; revised 7 June 2015; accepted 22 June 2015; published online 2 September 2015

Familial effects of gastric bypass surgery M Willmer et al

36 predicts intake in later life and low consumption has been associated with childhood obesity.13,21 Thus, the secondary aim of the current study was to explore possible changes in food choices of RYGB patients’ partners and children. SUBJECTS AND METHODS Recruitment Women eligible for participation in the study were identified from waiting lists for RYGB surgery at five clinics in Sweden. The criteria included being cleared for a primary RYGB, having at least one child between the ages of 7 and 14 years and being able to speak and understand Swedish. If the women were married to or cohabiting with a man, he was also asked to participate. Between April 2011 and October 2012, we recruited 69 families to the study. The data collection took place during two home visits to the families, with the first one carried out ~ 3 months before RYGB surgery and the second one approximately a year later, that is, 9 months post operatively. All subjects gave oral and written consent, and the study was approved by the Stockholm Regional Ethical Review Board (no 2009/1472-31/3). Not all families who took part in the first data collection were available for the follow-up home visit a year later. One declined continued participation in the study and two ultimately decided not to go through with their RYGB surgery. Three families had moved by the time of the second data collection and proved impossible to locate. Thus, 63 families with a total of 84 children and 37 men participated in both data collections. However, not all of them returned their questionnaires, despite at least three reminders by mail and telephone. For the first data collection they were 7 mothers and 14 children, and for the second they were 7 mothers and 13 children.

Data collection During the home visits, all participating family members were weighed and their height and waist circumference measured. They were also given questionnaires to complete after the visits and return by post. The children completed the Children’s Eating Attitudes Test (ChEAT), a 26-item questionnaire designed to measure children’s dieting behaviour and weight concerns.22 The items are in statement form and the child completes the questionnaire by responding to each statement using a sixpoint Likert-type scale ranging from ‘Never’ to ‘Always’. The ChEAT has been translated into a Swedish version, tested using a sample of Swedish 11- to 14-year-olds and were found to have acceptable internal consistency.23,24 Changes in the parents’ eating behaviour was measured using the Three-Factor Eating Questionnaire (TFEQ).25 The version of the TFEQ used in the present study is a 21-item self-report questionnaire measuring three

Table 1.

aspects of eating behaviour: cognitive restraint (CR), EE and uncontrolled eating. The items are in statement form and the respondent completes the instrument by picking one of four alternatives on a Likert-type scale (‘definitely true’, ‘mostly true’, ‘mostly false’ or ‘definitely false’). This version of the TFEQ has been translated into Swedish and shown to have acceptable internal consistency.26 All family members also completed a short food frequency questionnaire (FFQ) developed by the Swedish National Food Administration and designed to measure intake of certain foods found to be indicative of healthy eating.27,28

Statistical analysis Differences in mean TFEQ and the parents’ FFQ scores between the two time points were normally distributed and analysed using paired t-tests. The children’s changes in ChEAT and FFQ scores were analysed using linear regression models with robust variance (General Estimating Equations) in order to account for within-individual correlation.29 The models were adjusted for the children’s age and sex. We also compared whether any changes differed between sub-groups according to the children’s sex and weight status at baseline. This was done with the help of two interaction terms, sex × time point and weight status × time point. We also estimated the effect sizes of the changes in TFEQ and ChEAT scores by transforming the differences between the two time points into s.d. scores. Changes in prevalence of overweight and obesity were analysed using McNemar’s test. Finally, we used fixed-effects regression models to explore whether changes in the women’s TFEQ scores were associated with changes in their partners’ TFEQ and children’s ChEAT. All analyses were conducted using the Stata 12.1 (Stata Corp, College Station, TX, USA) software.

Missing data Out of the 63 participating families, 11 failed to complete and return one or both questionnaires. Furthermore, the TFEQ, ChEAT and FFQ had some missing values for some participants. These missing values were evaluated using multiple imputation models.30 The results presented are based on complete cases only, as the models did not yield significantly different results.

RESULTS The women’s weight loss following their RYGB (a mean of 11.6 body mass index (BMI) units) was to some extent mirrored by a small weight loss and decrease in waist circumference in their partners (0.9 BMI units and 4.7 cm, respectively) (Table 1). As shown in Table 2, the women’s TFEQ scores showed a mean increase of 2.1 points on the CR dimension, indicating higher levels of dietary restraint, and decreases in scores on the

Anthropometric characteristics of mothers, fathers and children 3 months before and 9 months after maternal RYGB surgery n

3 Months before maternal RYGB

Mothers Age (years) (mean (s.d.)) BMI (mean (s.d.)) Waist circumference (cm) (mean (s.d.))

63 63 62

39.0 (5.5) 39.2 (3.3) 117.7 (9.7)

Partners Age (years) BMI (mean (s.d.)) Overweight (number (%)) Obese (number (%)) Waist circumference (cm) (mean (s.d.))

37 37 37 37 37

42.0 (6.4) 29.7 (6.4) 10 (27.0%) 16 (43.2%) 104.1 (15.8)

Children Age (years) (mean (s.d.)) Overweight (number (proportion)) Obese (number (proportion))

81 81 81

10.0 (2.1) 45 (55.6%) 15 (18.5%)

Difference (95% CI)

P-values

− 11.6 (−12.3; − 10.9) − 28.7 (−30.8; − 26.6)

⩽ 0.001 ⩽ 0.001

43.1 (6.4) 28.8 (5.6) 14 (37.8%) 13 (35.1%) 99.4 (14.4)

− 0.89 (−1.52; − 0.26) 0.11 (−0.04; 0.26) − 0.08 (−0.20; 0.03) − 4.72 (−7.21; − 2.23)

0.007 0.103 0.082 ⩽ 0.001

11.1 (2.1) 41 (50.6%) 15 (18.5%)

− 0.05 (−0.13; 0.03) 0.00 (−0.06; 0.06)

0.157 1.000

9 Months after maternal RYGB 40.1 (5.5) 27.5 (3.1) 89.0 (8.6)

Abbreviations: BMI, body mass index; CI, confidence interval; RYGB, Roux-en-Y gastric bypass. P-values and 95% CIs from paired t-test (mean differences) and McNemar’s test (prevalence differences).

European Journal of Clinical Nutrition (2016) 35 – 40

© 2016 Macmillan Publishers Limited


37 Table 2.

Mothers’ and father’s TFEQ scores and children’s ChEAT scores 3 months before and 9 months after maternal RYGB surgery n


9 Months after maternal RYGB

Difference in score (95% CI)

P-value

Difference in s.d. score (95% CI)

Mothersa TFEQ-CR TFEQ-EE TFEQ-UE

47 52 49

13.2 15.2 21.2

15.3 9.9 13.5

2.11 (0.78; 3.43) − 5.31 (−6.66; − 3.96) − 7.78 (−9.62; − 5.93)

0.002 ⩽ 0.001 ⩽ 0.001

0.60 (0.22; 0.98) − 1.00 (−1.27; − 0.75) − 1.14 (−1.41; − 0.87)

Fathers TFEQ-CR TFEQ-EE TFEQ-UE

25 28 28

12.0 8.9 15.8

13.0 9.3 15.5

0.96 (−0.11; 2.03) 0.32 (−0.81; 1.46) − 0.29 (−1.78; 1.21)

0.079 0.579 0.708

0.29 (−0.03; 0.62) 0.09 (−0.21; 0.39) − 0.07 (−0.43; 0.29)

61 29 32

5.8 5.8 5.8 0.0 5.3 6.2 − 0.9

4.7 5.3 4.2 1.1 4.9 4.6 0.4

− 1.11 (−2.47; 0.24) − 0.54 (−2.78; 1.70) − 1.63 (2.90; − 0.36) − 1.09 (−3.46; 1.27) − 0.37 (−2.52; 1.78) − 1.69 (−3.13; − 0.25) − 1.32 (−3.72; 1.08)

0.108 0.637 0.012 0.365 0.737 0.022 0.282

− 0.27 (−0.59; 0.06) − 0.13 (−0.67; 0.41) − 0.39 (−0.70; − 0.09) − 0.26 (−0.83; 0.31) − 0.09 (−0.60; 0.43) − 0.41 (−0.75; − 0.06) − 0.32 (−0.89; 0.26)

Children ChEAT–allb Girlsb Boysb Difference between groupsb NW at baselinec OW at baselinec Difference between groupsc

31 30

Abbreviations: ChEAT: Children’s Eating Attitudes Test; GEE, General Estimating Equations; NW, normal weight at baseline; OW, overweight/obese at baseline; RYGB, RYGB, Roux-en-Y gastric bypass; TFEQ-CR, Three-Factor Eating Questionnaire–Cognitive Restraint; TFEQ-EE, Three-Factor Eating Questionnaire– Emotional Eating; TFEQ-UE, Three-Factor Eating Questionnaire–Uninhibited Eating. aUnadjusted comparisons, P-values and 95% confidence intervals from paired t-test. bMean differences adjusted for age. cMean differences adjusted for age and sex, using linear regression model with GEE.

uncontrolled eating and EE subscales. The men’s TFEQ scores did not change to any relevant extent between the two time points. When exploring changes in the children’s ChEAT scores, it was found that the participating boys had a decreased age-adjusted score of ~ 1.5 points (P = 0.012), indicating less dieting behaviour and weight concern, whereas the girls’ score had stayed largely the same. The children who were overweight or obese at baseline also showed a reduction (−1.7 points, P = 0.022), which was not seen in the normal-weight children (Table 2). Both these differences approached a moderate effect size (−0.39 s.d. for boys and − 0.41 s.d. for overweight/obese children). The women’s self-reported intake of soft drinks and sweets decreased and they also reported increased fruit and vegetable consumption. The men did not change their intake of the same foods noticeably (Table 3). The results from the children’s FFQ are somewhat inconsistent. The normal-weight children decreased their intake of soft drinks, from 2.8 to 1.6 times a week (P = 0.048), whereas the children who were overweight or obese at baseline did not report any changes in their consumption. This difference between the normal-weight and overweight/obese children proved to be significant when tested with an interaction term (P = 0.045). There were no significant changes in the children’s intake of sweets, but there was a difference between changes in normalweight and overweight/obese children’s intake of fruit and vegetables. The normal-weight children decreased their intake by 1.4 occasions/week, whereas the overweight/obese children increased theirs by 1.1 occasions/week. Although none of these changes reached significance, possibly owing to low power caused by the small sample sizes, the difference between the two groups’ changes did (P = 0.042). The fixed-regression models showed no association between the magnitude of the changes in the mothers’ eating behaviour and those of the partners’ and children’s (data not shown). DISCUSSION This study has demonstrated that women undergoing RYGB significantly change their eating behaviour. The increase in CR, which was statistically significant but not as marked as the corresponding decrease in EE and uncontrolled eating, is partly in © 2016 Macmillan Publishers Limited

accordance with results reported by Laurenius et al.,5 in whose study the participants reported increased CR 6 weeks post operatively but not 1 or 2 years post operatively. Increased CR is expected after surgery as a way of adapting to the new physiological condition, but as the patients establish regular eating patterns and lose weight, they will be reinforced in maintaining their new eating pattern. When a habit is established by contingent reinforcement, cognitive regulation is not required to the same extent, which might explain decreased CR in the longer term. The women also reported decreased uncontrolled eating and EE, again in line with previous findings.31,32 When it comes to the rest of the family, the results are more inconclusive. They are also more difficult to contextualize, owing to scarcity of research regarding the effect of bariatric surgery on the family members. We found that a woman’s RYGB seems to be only marginally associated with changes in her partner’s food choices and eating behaviour. Woodard et al.8 investigated 35 adult family members of RYGB patients. One year after their partner underwent RYGB, the spouses reported less emotional and uncontrollable eating. This finding was not replicated in our study, but the spouses reported a slight increase in CR (Table 2). This may be a contributing factor to their weight loss (−0.9 BMI units, P = 0.004). Watowicz et al.9 compared 45 obese children of RYGB patients with 90 obese age- and gender-matched control children, whose parents were also obese, but had not undergone bariatric surgery. They found, somewhat surprisingly, that the children of bariatric surgery patients were significantly more likely to self-report that they ate at the wrong time of day and that they usually ate two or more helpings of food. We found no corresponding negative effects of parental RYGB in our study. However, the difference in study design makes it difficult to compare the findings. The boys in our study improved their age-adjusted ChEAT scores (−1.63 points, P = 0.012), whereas the girls’ scores did not change correspondingly (−0.54, P = 0.637). It is also noteworthy that the children’s mean baseline score was higher than those found in other studies of 7- to 14-year-old Swedish children, which have ranged between 2.03 and 3.32.23,24 As for the children who were overweight or obese at baseline, they improved their score between the two data collection time European Journal of Clinical Nutrition (2016) 35 – 40


38 Table 3.

Mothers’, fathers’ and children’s food choices 3 months before and 9 months after maternal RYGB surgery n


9 Months after maternal RYGB

Difference (95% CI)

P-values

Mothersa Soft drinks/week Sweets/week Fruits and vegetables/week

50 52 51

2.2 4.4 10.6

0.3 2.1 12.7

− 1.85 (−2.53; − 1.17) − 2.27 (−3.37; − 1.18) 2.00 (0.57; 3.42)

o0.001 o0.001 0.007

Fathersa Soft drinks/week Sweets/week Fruits/vegetables/week

28 28 28

2.4 3.0 9.2

2.0 2.7 9.1

− 0.45 (−1.42; 0.53) − 0.26 (−1.03; 0.51) − 0.11 (−1.71; 1.50)

0.370 0.510 0.896

60 29 31

2.4 2.1 2.7 − 0.6 2.8 2.1 0.7 3.3 3.2 3.4 − 0.2 3.1 3.5 − 0.4 10.9 11.5 10.4 1.1 11.8 10.2 1.6

1.9 2.1 1.8 0.3 1.6 2.2 − 0.6 3.2 3.5 2.9 0.6 2.7 3.7 − 1.0 10.9 11.9 10.0 1.9 10.4 11.3 − 0.9

− 0.46 (−1.21; 0.29) 0.00 (−0.97; 0.96) − 0.88 (−1.89; 0.13) − 0.88 (−2.19; 0.43) − 1.25 (−2.48; − 0.01) 0.14 (−0.61; 0.90) 1.39 (0.03; 2.75) − 0.12 (−0.92; 0.67) 0.32 (−1.00; 1.64) − 0.53 (−1.24; 0.17) − 0.85 (−2.21; 0.51) − 0.41 (−1.24; 0.42) 0.15 (−1.02; 1.31) 0.56 (−0.75; 1.86) 0.03 (−1.25; 1.31) 0.43 (−1.50; 2.36) − 0.32 (−1.89; 1.25) − 0.75 (−3.14; 1.64) − 1.41 (−3.51; 0.69) 1.09 (−0.33; 2.50) 2.49 (0.09; 4.89)

0.231 0.995 0.087 0.188 0.048 0.710 0.045 0.760 0.640 0.136 0.220 0.334 0.803 0.404 0.964 0.662 0.691 0.538 0.190 0.133 0.042

Children Soft drinks/week–allb Girlsb Boysb Difference between groupsb NW at baselinec OW at baselinec Difference between groupsc Sweets/weekb Girlsb Boysb Difference between groupsb NW at baselinec OW at baselinec Difference between groupsc Fruits and vegetables/weekb Girlsb Boysb Difference between groupsb NW at baselinec OW at baselinec Difference between groupsc

26 34 60 29 31 27 33 58 27 31 25 33

Abbreviations: GEE, General Estimating Equations; NW, Normal weight at baseline; OW, overweight/obese at baseline; RYGB, Roux-en-Y gastric bypass. a Unadjusted comparisons, P-values and 95% confidence intervals from paired t-test. bMean differences adjusted for age. cMean differences adjusted for age and sex, using linear regression model with GEE.

points (Table 2). The mean difference in their score between the two time points was significant (P = 0.022) and the effect size was close to moderate (0.41 s.d.). Girls’ eating behaviours and weight concerns may be related to societal norms and ideals of thinness to a higher degree than boys’, and boys may therefore be more easily affected by changes in family eating habits and behaviours. There is some previous research to support this idea.33,34 As many obese women are in an almost constant state of weight cycling,35 the RYGB surgery and consequent dieting-like behaviours may not have been perceived as very different from their previous behaviour to the girls in our sample. However, there is no previous research showing the existence of these possible mechanisms in the context of parental bariatric surgery and they therefore remain speculative. The mothers of overweight or obese children may have been more likely to model healthy eating to their children than mothers of children who were normal weight. A study by Walters-Bugbee et al.7 found that women who had had RYGB surgery consciously modelled healthy eating behaviours for their children to a greater extent than women who had not yet had surgery. One might argue that dieting awareness and wanting to lose weight may be desirable behaviour in children who are overweight or obese. Certainly, there are appropriate ways in which these children may attempt lifestyle changes, such as engaging in physical activity that they find enjoyable, increasing intake of fruit and vegetables, and decreasing consumption of soft drinks. Although the ChEAT was specifically designed to measure disordered eating behaviours in children, irrespective of weight status,20 some items may represent acceptable behaviour for European Journal of Clinical Nutrition (2016) 35 – 40

overweight or obese children. In order to examine which items were driving the reduction in score, we divided the instrument into two sets of ‘acceptable’ (items 6, 11, 12, 16, 17, 22 and 23) and ‘non-acceptable’ (all other items) items and ran the original analyses on these. Although none of the results reached significance, the largest reduction was seen in the ‘nonacceptable’ items, indicating that the reduction in scores may indeed represent an improvement, even in overweight/obese children (data not shown). When it comes to changes in food choices, the women in the current study again reported changes that are largely in accordance with previous research.18,36 When considering the children’s intakes, one should keep in mind that a survey by the Swedish National Food Administration showed that 11-year-old children consumed soft drinks on average seven times per week and one may therefore suspect underreporting by the children in the present study (who reported a mean consumption of 2.4 times per week).37 Previous research has also shown that children with a higher BMI were more likely to underreport consumption of high-energy foods than children with a lower BMI.38 The normal-weight children in our study may have decreased their soft drink intake as a result of their mothers’ reduced consumption, but it is not entirely clear why the children who were overweight or obese at baseline should not then have reacted the same way. Even if the overweight or obese children underreported their soft drink intake to a greater extent than the normal-weight children, they should also have done so at the second data collection time point. © 2016 Macmillan Publishers Limited


39 When it comes to fruit and vegetable intake, the normal-weight children decreased their intake by almost the same amount as the overweight/obese children increased theirs. It is possible that selective maternal modelling of healthy eating habits may explain this, as described above. The present study has several strengths and limitations. All anthropometrical data were collected in the participants’ homes by the same researchers (MW and DB), using the same equipment. The psychometric instruments used have been shown to have good validity, as described above. As for limitations, the relatively short follow-up time and the small sample size should be mentioned. No formal a priori power calculations were performed, as the lack of previous research in the area meant that no basis for the necessary assumptions needed to make such a calculation could be found. However, it seems highly likely that the small sample sizes, especially for the partners and for the gender- and weight status-specific analyses of the children, resulted in low power. In addition to this, the short follow-up time means that the women were still in a rapid weight loss phase at the time of the second home visit. As it has been shown that RYGB patients typically regain some of the lost weight in the long term,39 and that their eating behaviour and food choices deteriorate,40 it is possible that the eating behaviour and food choices of other family members may be similarly affected over time. In order to make the questionnaire as short and user-friendly as possible, we decided not to include questions on which of the family members held the main responsibility for purchasing and preparing the family’s meals, which may have added further information on the mechanisms underlying the results. We would suggest this as a possible future research direction. In conclusion, the present study showed that although male partners of female RYGB patients seem unaffected in terms of eating behaviour and food choices, the eating behaviour of the patients’ children may be improved. The results also showed that the normal-weight children, but not those who were overweight or obese, reduced their consumption of sugar-sweetened beverages. It would be useful for future studies to focus on further exploring these apparent differences in changes in eating behaviour and to identify the mechanisms behind them. CONFLICT OF INTEREST The authors declare no conflict of interest.

ACKNOWLEDGEMENTS The current study was funded by a grant to Finn Rasmussen from the Swedish Council for Working Life and Social Research (grant number: 2008-0654), Stockholm County Council (ALF), NovoNordisk fund, Karolinska Institutet Diabetes Theme center, the National School in Caring Sciences at Karolinska Institutet (NFV) and through the Erling-Persson Family Foundation.

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