The Effects of Psyllium on Lipoproteins in Type II Diabetic Patients

SHORT COMMUNICATION The effects of psyllium on lipoproteins in type II diabetic patients

G Sartore, R Reitano, A Barison, P Magnanini, C Cosma, S Burlina, E Manzato, D Fedele and A Lapolla

Department of Medical and Surgical Sciences, University of Padua, Padua, Italy

We examined the effects of 2 months of psyllium treatment in optimizing metabolic control and lipoprotein profile, and its postprandial effects on lipids in type II diabetes. We recruited 40 type II diabetic patients who were on sulfonylureas and a controlled diet, sequentially assigning them to psyllium treatment (G1) or to a control group (G2) treated with dietary measures alone. After 2 months of treatment, body mass index, waist circumference, HbA1c (hemoglobin A1c) and fasting plasma glucose levels had significantly decreased in both groups. There were no postprandial differences in the lipoprotein profile between the two groups. Triglycerides were significantly lower in G1, but not in G2. Our study contributes toward elucidating the effects of psyllium on serum lipids, and suggests that psyllium treatment may help in reducing triglycerides (a known risk factor for cardiovascular disease) in type II diabetic patients. European Journal of Clinical Nutrition (2009) 63, 1269–1271; doi:10.1038/ejcn.2009.60; published online 22 July 2009

Keywords: type 2 diabetes; lipoproteins; psyllium; dietary fiber

Introduction This study examined the effects of a 2-month psyllium treatment in optimizing metabolic control and lipoprotein In addition to pharmacological treatments, dietary measures profile, and its postprandial effects on lipids, in type II (in particular, the use of fibers) have recently become diabetic patients. important in the treatment of diabetes. Soluble fibers render food absorption slower, and their mass effect accelerates the passage of food through the intestinal tract. There are different opinions in the literature regarding this issue; Patients and methods however, some authors say that a diet rich in fiber could optimize metabolic control (Sierra et al., 2002), whereas A total of 40 type II diabetic patients were recruited for the others believe that fiber alone is unable to achieve this effect study. All patients required treatment with sulfonylureas and (Jarjis et al., 1984). a controlled diet. None were taking any drugs that directly The second important issue concerns the use of fiber for affected lipoproteins. These patients had no history of reducing cholesterol. Several, but not all, studies (Neal and gastrointestinal and other major diseases. Balm, 1990; Van Rosendaal et al., 2004) have found that Their daily energy intake during the study was 1800 Kcal psyllium supplementation significantly lowered total and and consisted of carbohydrates (52%), lipids (30%), proteins low-density lipoprotein (LDL) cholesterol concentrations in (18%) and fiber (26 g). Patients were sequentially assigned individuals with hypercholesterolemia (Anderson et al., either to treatment with psyllium 3.5 g (one dose of sugar- 2000) and in type II diabetic patients (Rodriguez-Moran free Agiofibre, Plantago ovata, Madaus SA, Barcelona, Spain), et al., 1998; Sierra et al., 2002). Further research is needed to thrice a day, before breakfast, lunch and dinner (G1), or to a clarify the effects of psyllium on serum lipids. control group (G2) treated with the prescribed diet alone. Patients treated with psyllium were instructed to mix each sachet of fiber in 250 ml of water, followed by 50 ml water to Correspondence: Dr G Sartore, Department of Medical and Surgical Sciences, rinse the glass and to drink the mixture before each meal. Univeristy of Padua, 35143 Padua, Italy. All patients were followed up for 8 weeks. At baseline (T0), E-mail: [email protected] Received 28 October 2008; revised 15 May 2009; accepted 16 May 2009; and again at the end of the study (T1), they were tested for published online 22 July 2009 body weight, body mass index, waist circumference, blood Psyllium in type II diabetes G Sartore et al 1270 pressure, glycemia, HbA1c (hemoglobin A1c), lipids and et al., 1972). The study protocol was approved by the local lipoproteins. At T0 and T1, all patients in both groups ethics committee. Written informed consent was obtained were given a test meal consisting of yogurt (200 g) and two from all participants before they joined the study. packets of wholemeal crackers (40 g of carbohydrates), to which patients in G1 added 3.5 g of psyllium. Levels of total cholesterol, high-density lipoprotein cholesterol and tri- Statistical analyses glycerides were measured in all patients immediately before The SPSS software, 16.0 (Chicago, IL, USA) was used for the (fasting levels) and 120 min (T120) after the test meal. statistical analyses. Data were expressed as mean±s.d. Glycemia and glycated hemoglobin were tested in the Student’s t-test for paired data was used to compare the data central laboratory at the Padova General Hospital to obtained at baseline and at the end of the study, and before standardize the results for all patients. Venous glycemia and after the test meal, within each group of patients. The was measured using the glucose–oxidase method and HbA1c t-test for unpaired data was used to assess differences between by high-performance liquid chromatography (Jaynes et al., the two groups. A value of Po0.05 was considered significant. 1985). Cholesterol and triglycerides were measured using the enzymatic method (Wahlefeld, 1976). High-density lipoprotein cholesterol was assayed after precipitating lipoproteins containing apoB (apolipoprotein B) with polyanions (Lipid Results Research Clinics Program, 1982). LDL cholesterol was calculated using the Friedewald formula, except in cases for On the basis of reports obtained from our patients, psyllium whom triglycerides were higher than 300 mg/dl (Friedewald treatment was readily acceptable and well tolerated as a

Table 1 Anthropometric and glyco-metabolic parameters in both groups before (T0) and after 8 weeks of psyllium treatment (T1)

Sex G1 (treatment) G2 (control) Age (years) 14 M, 6 W 13 M, 7 W 61±8.7 60±8

T0 T1 T0 T1

BMI (kg/m2) 30.09±3.93a 29.35±3.90 30.48±2.90a 29.50±2.87 Waist circumference (cm) 101.75±11.20b 99.85±11.42 104.13±8.08b 101.33±7.37 Systolic BP (mm Hg) 146.5±18.14b 136±17.52 138.53±18.52 136.18±18.50 Diastolic BP (mm Hg) 85.5±8.26b 80.75±7.48 80.88±9.22 80.59±7.88 HbA1c (%) 6.78±0.44b 6.58±0.50 7.03±0.58a 6.60±0.45 FPG (mg/dl) 140.39±23.80b 135.56±19.92 154.25±23.79a 135.85±26.38

Abbreviations: BMI, body mass index; BP, blood pressure; FPG, fasting plasma glucose; HbA1c, hemoglobin A1c; M, men; W, women. Student’s t-test for unpaired data was used to compare the two groups. aT0 vs T1 Po0.001. bT0 vs T1 Po0.05.

Table 2 Total, HDL, LDL cholesterol and triglycerides in patients treated with psyllium (G1) and controls (G2) at baseline (T0) and at the end of the study (T1), that is, before the first (T0) and second meals (T1), and after the first and second test meals (T120)

Time G1 G2

First meal Second meal First meal Second meal

T0 T120 T1 T120 T0 T120 T1 T120

Total cholesterol (mg/dl) 187±38a 183±37 178±38 176±39 194±33a 187±27 187±28 178±33 HDL cholesterol (mg/dl) 48±12 47±13 47±13 47±13 44±943±944±944±9 LDL cholesterol (mg/dl) 113±32b 106±32 110±33b 103±34 126±32b 115±24 119±23b 111±28 Triglycerides (mg/dl) 127±44c,d 151±57 109±33d 141±42 112±43d 147±63 111±49d 140±65

LDL, low-density lipoprotein; HDL, high-density lipoprotein. Student’s t-test for paired data was used to compare times within each group of patients. aTotal cholesterol T0 vs T1 Po0.05. bLDL cholesterol T0 vs T120 at 1st meal, Po0.001; and at 2nd meal, Po0.05. cTriglycerides T0 vs T1 Po0.05. dTriglycerides T0 vs T120 at 1st and 2nd meals, Po0.001.

European Journal of Clinical Nutrition Psyllium in type II diabetes G Sartore et al 1271 supplement to a standard diet for diabetes. No adverse events treatment group and in our control group, with no were recorded. significant difference between the two. On the other hand, The treatment and control groups, G1 and G2, did not triglycerides were only significantly lower in G1, after differ significantly at baseline in terms of age, body weight, 8 weeks of psyllium treatment. Further studies are required body mass index, waist circumference, blood pressure, in type II diabetic patients to confirm these findings, which glyco-metabolic parameters or lipoproteins (Table 1). No might mean that psyllium treatment has different effects on significant differences were observed between the two different populations and different individuals; hence, it groups with regard to sulfonylurea dosage and daily intake. would need to be tailored (Sierra et al., 2002). It would seem After 8 weeks of psyllium treatment, body mass index, to be necessary to continue the treatment for at least 2 waist circumference, HbA1c and fasting plasma glucose months to obtain effective results. levels were significantly lower in both groups, whereas blood Our study helps to document the effects of psyllium on pressure was significantly lower in G1, but not in G2 serum lipids in different groups of individuals and suggests (Table 1). that psyllium may be useful in reducing triglycerides (a As for lipoprotein profile, triglycerides were significantly known risk factor for cardiovascular disease) in patients with lower after 8 weeks of psyllium treatment in G1, whereas no type II diabetes. such reduction was seen in G2 (Table 2). The test meal assessment showed no differences between the two groups; after the meal, total and LDL cholesterol decreased significantly, whereas triglycerides increased sig- References nificantly and high-density lipoprotein cholesterol remained Anderson JW, Allgood LD, Lawrence A, Altringer LA, Jerdack GR, the same (Table 2). Hengehold DA et al. (2000). Cholesterol-lowering effects of psyllium intake adjunctive to diet therapy in men and women with hypercholesterolemia: meta-analysis of 8 controlled trials. Am J Clin Nutr 71, 472–479. Discussion Clark CA, Gardiner J, McBurney MI, Anderson S, Weatherspoon LJ, Henry DN et al. (2006). Effects of breakfast meal composition on The palatability of psyllium fiber makes it acceptable and second meal metabolic responses in adults with type 2 diabetes easier to eat than vegetables with an equivalent fiber content mellitus. Eur J Clin Nutr 60, 1122–1129. in the diet. Psyllium could be useful in improving compli- Friedewald WT, Levy RI, Fredrickson DS (1972). Estimation of the concentration of low-density lipoprotein cholesterol in plasma, ance in patients who are prescribed the ingestion of large without use of the preparative ultracentrifuge. Clin Chem 18, 499–502. amounts of fibers. Jarjis HA, Blackburn NA, Redfern JS, Read NW (1984). The effect of The improvement in glyco-metabolic parameters noted in ispaghula (Fybogel and Metamucil) and guar gum on glucose Br J Nutr both our groups probably relates to a good compliance with tolerance in man. 51, 371–378. Jaynes PK, Willis MC, Chou PP (1985). Evaluation of a mini-column the diet because of all patients frequently attending the chromatographic procedure for the measurement of haemoglobin dietetic clinic (twice in 8 weeks). A1c. Clin Biochem 18, 32–36. An earlier study (Clark et al., 2006) using a test meal found Lipid Research Clinics Program (1982). Lipid and lipoprotein analyses. Hainline A, Karon J, Lippel K (eds). In: Manual of no evidence of any postprandial improvement in free fatty Laboratory Operations, 2nd edn, US Department of Health and acids with psyllium treatment, but provided no data on Human Service: Washington, DC. pp 63–77. lipoproteins. In our study, psyllium did not seem to reduce Neal GW, Balm TK (1990). Synergistic effects of psyllium in postprandial cholesterol and triglyceride levels. the dietary treatment of hypercholesterolemia. SMedJ83, 1131–1137. A meta-analysis conducted on eight studies showed that Rodriguez-Moran M, Guerrero-Romero F, Lazcano-Burciaga GJ psyllium ingestion improved cholesterol and total cholester- (1998). Lipid- and glucose-lowering efficacy of Plantago Psyllium ol LDL levels in patients who were on a low-fat diet in type II diabetes. J Diabetes Complications 12, 273–278. (Anderson et al., 2000). Another study (Neal and Balm, Sierra M, Garcia JJ, Fernandez N, Diez MJ, Calle AP, Farmafibra Group (2002). Therapeutic effects of psyllium in type 2 diabetic patients. 1990) found a significant reduction in total cholesterol and Eur J Clin Nutr 56, 830–842. LDL cholesterol in men, but not in women. Most of the Van Rosendaal GMA, Shaffer EA, Alun LE, Brant R (2004). Effect of studies on this issue were carried out on hypercholester- administration on cholesterol-lowering by psyllium: a randomized olemic patients and this could explain their results. Our cross-over study in normocholesterolemic or slightly hypercho- lesterolemic subjects. Nutr J 28, 3–17. patients were all normocholesterolemic and this might have Wahlefeld AW (1976). Triglycerides determination after enzymatic influenced our findings. In fact, we recorded a mild decrease hydrolysis. In: Bergmeyer HU (ed). Methods of Enzymatic Analyses. in total and LDL cholesterol after 2 months in both our Academic Press: New York. pp 1831–1835.

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