Operation med gastric bypass hjälper personer med fetma att gå ner i vikt. Enligt en aktuell avhandling från Göteborgs universitet medför fetmakirurgin ett flertal faktorer som bland annat bidrar till hälsosammare livsmedelsval och normaliserat ätbeteende.
– Operationen fungerar ofta som en hjälp till att förändra sitt ätbeteende, berättar dietisten Anna Laurenius som i sin avhandling visar att operation med gastric bypass på flera olika sätt bidrar till hälsosammare matvanor som främjar viktminskning.
– Efter operation äter man långsammare och man blir mätt på mindre portioner. Vi ser tydligt att personerna som opererats med gastric bypass äter mindre fett och ökar mängden frukt och grönsaker – alltså helt enligt de rekommendationer vi ger för viktminskning, även vid vanlig kostbehandling, menar dietisten Anna Laurenius.
Dietisten är en nyckelperson i vårdteamet och har den unika kompetens som krävs för att de opererade patienterna ska få information och kunskap kring kosten, både före och i direkt anslutning till operationen, och under uppföljningstiden. Dietisten har dessutom en viktig roll i att utbilda övrig vårdpersonal. Forskning inom området leder till att råd och rekommendationer utvecklas och förfinas:
– Tidigare har vi rekommenderat att gastric bypass-opererade patienter ska äta väldigt ofta, nu har vi omvärderat kostråden och vi tror att det oftast räcker med de vanliga huvudmålen och kanske någon frukt däremellan.
Dumping som verktyg
Eftersom maten passerar förbi magsäcken och går direkt ut i tarmen kan operationen leda till så kallade dumping-symtom som till exempel ger trötthet och illamående efter måltid.
Avhandlingen ”Roux-en-Y gastric bypass as treatment for morbid obesity: studies on dietary intake, eating behavior and meal-related symptoms” försvaras av dietist och doktorand Anna Laurenius den 19 april i Sahlgrens aula, Blå stråket 5, SU/Sahlgrenska, Göteborg. Huvudhandledare är Torsten Olbers, Sahlgrenska Akademin, Göteborgs Universitet.
Abstract
Background and aims: Roux-en-Y gastric bypass (RYGB) is now a common treatment for obesity with well-documented effects on long-term weight reduction, health-related quality of life, obesity-related morbidity and mortality. There is a need for a better understanding of changes in dietary intake and meal-related symptoms after RYGB.
The aim of this thesis was to study these phenomena and to improve current treatment protocols. Methods: Forty-three adults (31 women, 12 men; mean age 42.6 years, mean BMI 44.5 kg/m²) were followed in a longitudinal cohort study and examined preoperatively and at six weeks, one and two years after surgery (Paper I and II). They completed the Three-Factor Eating Questionnaire (TFEQ-R21) on attitudes to food, and questionnaires on dietary intake and meal pattern; in addition, a test meal ad libitum was administered and portion size and eating rate were assessed. A Dumping Symptom Rating Scale (DSRS) was developed and evaluated for its reliability and construct validity over two years on 124 respondents of whom 43 adults from Paper I and II and in addition 81 adolescents (Paper III). Thirty-one non-obese subjects served as reference group (Paper II and III). Another eight RYGB patients with hypoglycemia -like symptoms and eight patients with no hypoglycemia -like symptoms ingested a liquid carbohydrate meal. Insulin, plasma glucose, glucagon-like peptide 1 (GLP-1) and glucagon were measured intermittently up to 180 minutes after the meal. Results: The dietary questionnaire showed decreased energy intake, Food weight fell initially but was not lower two years after surgery resulting in a significantly decreased dietary energy density at two years after surgery. The meal test showed decreased portion size despite meal duration remaining constant, resulting in a reduced eating rate. Number of meals increased, with more meals in the mornings. TFEQ-R21 revealed decreased emotional and uncontrolled eating, whereas there was a transient increase in cognitive restraint six weeks after surgery. Most subjects reported mild or no dumping symptoms, although 6–12% had persistent problems – in particular, postprandial fatigue, need to lie down, nausea, and feeling faint – two years after surgery. The result of the validation process of DSRS was satisfactory overall. The patients with a history of hypoglycemia-like symptoms after RYGB demonstrated neither lower plasma glucose nor greater insulin response compared to asymptomatic patients in response to a liquid carbohydrate meal, but they perceived more symptoms. Conclusion: After RYGB, patients displayed major changes in eating behavior and meal pattern, suggesting that RYGB drives the individual to an eating behavior that promotes weight loss. Despite lack of association between the reduction in dietary energy density and percentage weight loss, changes in food choice were overall nutritionally beneficial. Dumping symptoms were rarely evident, but some patients reported persistent problems up to two years after surgery. DSRS is a reliable clinical screening instrument to identify patients with pronounced dumping symptoms. The mechanisms of action behind the origin of hypoglycemia-like symptoms remain obscure and need further exploration.
Fakta om fetmakirurgi
I Sverige utförs ca 8000 gastric bypass-operationer årligen. För att bli opererad krävs ett BMI på 40 (BMI 35 vid t ex diabetes, högt blodtryck eller sömnapné). Gastric bypass har väldokumenterad effekt på långsiktig viktminskning, livskvalitet, fetmarelaterad sjuklighet och dödlighet, bl a genom studien ”Swedish Obese Subjects” som följer 2000 opererade personer under en tjugoårsperiod.
Läs mer om avhandlingen, ladda ner abstract och avhandlingen utan lösenord som freeware
https://gupea.ub.gu.se/handle/2077/32372
Nyhetsinfo
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