| Abstract | Svrha rada bila je utvrditi kako različiti načini pripreme i termičke obrade namirnica utječu na sadržaj kalcija, fosfora i proteina u gotovoj hrani. Dobiveni rezultati primijenjeni su u izradi preporuka i pripremi jelovnika koji optimiziraju sadržaj fosfora, kalcija i proteina za pacijente na hemodijalizi. Standardnim AOAC metodama određen je sadržaj suhe tvari, proteina, kalcija i fosfora u krumpiru, svježoj i smrznutoj mrkvi, smrznutim mahunama, piletini, junetini, svinjetini, smrznutom osliću, tjestenini i riži prije i poslije pripreme i termičke obrade. Rezultati pokazuju da termička obrada većine ispitanih namirnica uzrokuje značajno smanjenje sadržaja fosfora bez značajnog smanjenja udjela proteina. Kod svježeg i zamrznutog povrća gubici fosfora su od 27% do 43%, kod različitih vrsta mesa 10%- 49%, tjestenine 7%, te riže 22,8%. Dobiveni rezultati koristili su se u istraživanju koje je obuhvaćalo 47 pacijenata koji su podijeljeni u eksperimentalnu (n=25) i kontrolnu skupinu (n=22). Svi su pacijenti dobili standardnu edukaciju o prehrani bolesnika na hemodijalizi. Ispitanici u eksperimentalnoj skupini primili su dodatnu edukaciju o načinima pripreme i termičke obrade hrane za smanjenje sadržaja fosfora, zadržavanje proteina i odgovarajuci sadržaj kalcija. Na početku i tijekom istraživanja, 12 mjeseci vršena su antropometrijska mjerenja, procijenjen je dnevni unos nutrijenata sedmodnevnim dnevnikom prehrane te su mjereni biokemijski parametri standardnim metodama.Tijekom jednogodišnje studije na pacijentima srednja promjena razine fosfata u serumu je smanjenje -0,3 interkvartilnog raspona (IQR) -0,4-0,1 u eksperimentalnoj skupini i -0,2 IQR -0,5-0,1 u kontrolnoj skupini. Albumini u serumu, normalizirana katabolička stopa proteina (nPCR) i antropometrijski status bolesnika nije se značajno promijenio, a terapija vezačima fosfora značajno se smanjila u eksperimentalnoj skupini. Koncentracija paratiroidnog hormona (PTH) u plazmi u kontrolnoj skupini značajno se povećala nakon 6 (p=0.031) i 12 mjeseci (p=0,035), dok se u eksperimentalnoj skupini nakon 6 mjeseci značajno smanjila (p=0,035). Pružanje dodatne edukacije pacijentima na hemodijalizi o specifičnim metodama za pripremu i termičku obradu hrane i primjena preporuka kod pripreme obroka mogu smanjiti razinu serumskih fosfata, PTH u plazmi i doze terapije vezačima fosfora bez značajnog povećanja terapije kalcitriolom i negativnog utjecaja na prehrambeni status bolesnika. |
| Abstract (english) | The purpose of this work was to examine how different methods of foodstuff preparation and thermal processing influence the levels of calcium, phosphorus and protein in the final food. The results have been used to generate recommendations for preparing meals optimized for phosphorus, calcium and protein content for hemodialysis patients. Standard AOAC methods were used to determine content of dry matter, protein, calcium and phosphorus in potatoes, fresh and frozen carrots, frozen green beans, chicken, veal, pork, frozen hake, pasta and rice. These determinations were made before and after preparation and thermal processing. Thermal processing of most foodstuffs did not substantially affect protein content but significantly reduced phosphorus content, by 27-43% in fresh and frozen vegetables, 10-49% in various types of meat, 7% in pasta and 22.8% in rice. These results were used to design a controlled study involving 47 hemodialysis patients, all of whom received standard dietary education. A subset of 25 patients received additional education about methods for preparing and thermally processing food in ways that reduce phosphorus content while maintaining content of protein and calcium. Anthropometric measurements and standard biochemical tests were conducted on all patients at baseline and during 12-month follow-up. Daily intake of various nutrients was estimated based on 7- day food diaries. Over the 12-month study, the serum phosphate level fell in the patients who received additional education (average change, -0.3; interquartile range (IQR), -0.4 to -0.1) as well as in patients who received only standard education (-0.2; IQR, -0.5 to -0.1). In neither group were significant changes observed in serum albumin, normalized protein catabolic rate (nPCR) or anthropometric measurements. In contrast, the number of patients on phosphate-binder therapy significantly decreased during follow-up among patients who received additional education. Plasma levels of parathyroid hormone (PTH) in patients who received only standard education was significantly higher than baseline at 6 months (p = 0.031) and 12 months (p = 0.035), while plasma levels were significantly lower than baseline at 6 months (p = 0.035). Educating patients about these methods can result in lower levels of serum phosphate and plasma PTH as well as reduced need for phosphate-binder therapy, without increasing the use of Kalcitriol or compromising nutritional status. |
