PRACE ORYGINALNE
Danuta Owczarek1 Dorota Cibor1 Kinga Sałapa2 Artur Jurczyszyn3 Tomasz Mach1
Homocysteine in patients with inflammatory bowel diseases
Department of Gastroenterology, Hepatology and Infectious Diseases, Jagiellonian University Medical College, Krakow Chair of Department: Prof. dr hab. Tomasz Mach
Background: Hyperhomocysteinemia seems to be a common phenomenon in both patients with ulcerative colitis and Crohn’s disease. Many factors including deficiencies of cobalamin, folate and pyridoxine, smoking habits, alcohol and coffee intake, some medications and age may predispose subjects to hyperhomocysteinemia. The study aimed to evaluate homocysteine levels in an inflammatory bowel disease cohort as dependent of life style and disease activity. Methods: 85 consecutive patients with inflammatory bowel disease (38 with Crohn’s disease and 47 with ulcerative colitis) and 65 control subjects were included in the prospective study. The following parameters were analyzed: disease activity, duration of the disease, location of pathological changes, presence of complications, current medications, past surgical procedures, smoking history, concomitant diseases, biochemical parameters and plasma homocysteine levels. Results: Mild hyperhomocysteinemia was found in 16 patients with Crohn’s disease (42%), 19 patients with ulcerative colitis (40%) and 19 patients in the control group (29%) (p = 0.59). There was not any significant correlation between homocysteine level and disease activity. Only folic acid supplementation and gender affected homocysteine level. Folic acid intake led to reduction of homocysteine levels in all groups of patients (11.8μmol/l vs 8.33μmol/l, p = 0.0065 in Crohn’s disease patients and 10.94μmol/l vs 7.78μmol/l, p = 0.0069 in ulcerative colitis patients). Conclusion: Homocysteine level in patients with inflammatory bowel disease is mostly normal or slightly elevated. Disease activity does not have an impact on homocysteine level. Folic acid is the most important factor having an influence on homocysteine level in patients with inflammatory bowel disease.
1
Department of Bioinformatics and Telemedicine Jagiellonian University Medical College, Krakow Chair of Department: Prof. dr hab. Irena Roterman-Konieczna 2
Clinic of Hematology, Jagiellonian University Medical College, Krakow Chair of Department: Prof. dr hab. A. Skotnicki 3
Additional key words: Crohn’s disease folic acid homocysteine ulcerative colitis. Dodatkowe słowa kluczowe: choroba Crohna kwas foliowy homocysteina wrzodziejące zapalenie jelita grubego
Adres do korespondencji: Danuta Owczarek Sniadeckich 5, 31-531 Krakow e-mail:
[email protected] tel. + 48 12 424 73 40 Fax. +48 12 424 73 80
Przegląd Lekarski 2014 / 71 / 4
Homocysteina w chorobach zapalnych jelit Wprowadzenie: U chorych z wrzodziejącym zapaleniem jelita grubego i chorobą Crohna często obserwuje się hiperhomocysteinemię. Wśród czynników mogących sprzyjać temu zjawisku wymienia się: niedobory kobalaminy, kwasu foliowego, pirydoksyny, palenie papierosów, nadmierne spożycie alkoholu, kawy, niektóre leki i wiek. Celem przeprowadzonego badania była ocena poziomu homocysteiny u pacjentów z nieswoistymi zapaleniami jelit w zależności od stylu życia i aktywności choroby. Metodyka: Do badania włączono 85 kolejnych pacjentów z rozpoznanym nieswoistym zapaleniem jelit (38 z chorobą Crohna i 47 wrzodziejącym zapaleniem jelita grubego) oraz 65 osób do grupy kontrolnej. Analizie poddano następujące parametry: aktywność choroby, czas trwania choroby, lokalizację zmian zapalnych, obecność powikłań, aktualne leczenie, przebyte zabiegi operacyjne, choroby towarzyszące, styl życia, parametry biochemiczne i poziom homocysteiny. Wyniki: Łagodną hiperhomocysteinemię stwierdzono u 16 pacjentów z chorobą Crohna (42%), 19 pacjentów z wrzodziejącym zapaleniem jelita grubego (40%) i 19 pacjentów z grupy kontrolnej (29%) (p = 0,59). Nie stwierdzono istnienia korelacji pomiędzy poziomem homocysteiny a aktywnością choroby zapalnej. Jedynymi czynnikami mającymi wpływ na poziom homocysteiny były: suplementacja kwasu foliowego i płeć. Suplementacja kwasu foliowego prowadziła do obniżenia poziomu homocysteiny we wszystkich badanych grupach (11,8 μmol/l vs 8,33 μmol/l, p = 0,0065 u pacjentów z chorobą Crohna i 10,94 μmol/l vs 7,78 μmol/l, p = 0,0069 u pacjentów z wrzodziejącym zapaleniem jelita grubego). Wnioski: Stężenie homocysteiny u większości pacjentów z nieswoistymi chorobami jelit jest prawidłowe lub nieznacznie podwyższone. Aktywność choroby nie ma wpływu na poziom homocysteiny. Suplementacja kwasu foliowego jest najistotniejszym czynnikiem mającym wpływ na poziom homocysteiny u chorych z nieswoistymi stanami zapalnymi jelit. 189
Introduction Homocysteine (Hcy) is a sulfur amino acid generated in consequence of demethylation of methionine that originates from animal proteins. The principal Hcy fraction in blood is amide-bonded protein-bound Hcy; N-Hcy-hemoglobin accounts for 75% of the pool, while N-Hcy-albumin – for approximately 22%. Free Hcy is only 1-2%, thiocyclic Hcy – homocysteine thiolactone approximately 0.002–0.3%, and the remaining Hcy has an oxidized form [1]. Elevated Hcy levels may lead to endothelial damage through intensification of intravascular oxidative stress and a decrease in bioavailability of nitric oxide (NO) and in consequence to impairment of endothelium-dependent vascular relaxation [2-5]. Moreover, there are investigators that report the pro-inflammatory activity of hyperhomocysteinemia and publications stating that the condition itself is a consequence of an inflammatory process in progress [6,7]. Hyperhomocysteinemia is considered also as one of factors contributing to a state of hypercoagulability in IBD resulting from endothelial dysfunction [8]. Hyperhomocysteinemia occurs when Hcy metabolism is disturbed. Such disturbances are noted in case of cofactor deficiency or gene mutations [8]. In addition, there are numerous external factors that affect Hcy levels [9]. Dietary deficiency of folates and group B12 vitamins, as well as a high protein supply increase the level of Hcy [1,10]. Hcy levels increase with age and are higher in post-menopausal women. Mild hyperhomocysteinemia (plasma total Hcy 10–30 µmol/l) is common especially in the elderly [11]. Tobacco smoking, alcohol abuse and drinking large amounts of coffee also lead to Hcy level increase [9,11,12]. Medications that elevate Hcy values include methotrexate, cyclosporin, sulphalazine, antidiabetic agents, anti-seizure medications, levodopa, fibrates and theophylline [13]. Some reports describe a drop in Hcy levels following glucocorticosteroid administration [14]. In addition, hyperhomocysteinemia is concomitant with such entities as atherosclerosis, ischemic heart disease, cerebral strokes, phlebothrombosis, pregnancy complications, chronic renal insufficiency, cancer, diabetes, hypothyroidism, psoriasis, rheumatoid arthritis, systemic lupus erythematosus, Alzheimer’s disease and nonspecific enteritis [13]. Elevated Hcy levels are observed both in Crohn’s disease (CD) and in ulcerative colitis (UC), however data are still controversial. The above considerations have led the present investigators to studying the levels of Hcy in patients with IBD as depending on their life style and disease activity. Material and Methods Study population We studied 85 consecutive patients, including 47 individuals with diagnosed UC (25F, 22M), aged 19 to 69 years, and 38 patients with CD (18F, 20M), aged 18 to 52 years. The inclusion criteria were as follows: age >18 years, IBD diagnosed on the basis of histopathological, endoscopic and radiolo190
gic criteria [15]. Within the past 3 months, the patients were to be treated only with mesalamine or azathioprine. All the patients treated with azathioprine had folic acid supplementation (5mg per day). The exclusion criteria were pregnancy, other active inflammatory disease, hyperthyroidism, hypothyroidism, renal failure, liver injury, diabetes, cancer, prior intestinal resections, psoriasis, rheumatoid arthritis and lupus erythematosus, as well taking such medications as cyclosporine, methotrexate, and glucocorticosteroids in the last 3 months, and supplementation of vitamin B. The CD group was presented and characterized in a previous paper of Owczarek et al. [16]. The control group included 65 healthy (not reporting chronic diseases) volunteers (31F, 34M) aged 19-65 years. The patients enrolled into the study were followed at the Department of Gastroenterology, Hepatology and Infectious Diseases, Jagiellonian University Medical College, Krakow, Poland. All the participants gave their informed consent to participate in the study. The research was conducted in accordance with the Helsinki Declaration. Medical examination A detailed medical history was taken from every patient, involving duration of the disease, location of pathological changes, disease activity, complications, current medications, past surgical procedures, smoking history, alcohol and coffee intake, history of thromboembolic events and concomitant diseases. The patients were subjected to physical examinations. Complications were defined as the presence of an abscess, fistula and non-intestinal disease in association with IBD. To determine the location of lesions in UC and CD, the Montreal classification was used [17]. In the medical history pertaining to past surgical procedures, only operations performed in relation to the primary disease were taken into consideration. For the assessment of CD activity, there was calculated the Crohn’s Disease Activity Index (CDAI) [18]. The CDAI combines the evaluation of vital parameters, clinical findings, and medical history. The activity of UC was judged using the disease activity index (DAI) [19]. DAI is a composite score based on the daily number of stools, visible blood in stool, appearance of the colonic mucosa by endoscopy, and the physician’s global assessment. Each variable was scored 0-3 points, with the total index score ranging from 0-12. Laboratory tests In each patient, fasting blood was collected in the morning. We determined red blood cell, white blood cell, hemoglobin, hematocrit, platelet count, glucose, creatinine, albumin, C-reactive protein, Hcy. The reference ranges for Hcy were 5-10 µmol/l. Values between 10-20µmol/l were classified as mild hyperhomocysteinemia, between 20-30 µmol/l as moderate hyperhomocyteinemia and above 30 µmol/l as severe hyperhomocysteinemia. Biochemical measurements (C-reactive protein, albumin, glucose, and creatinine) were studied with a Modular P clinical chemistry analyzer
(Roche Diagnostics GmbH, Mannheim, Germany). A complete blood count was performed with a Sysmex XE-2100 hematology automated analyzer (Sysmex, Kobe, Japan). Hcy levels were determined in plasma versenate by high pressure liquid chromatography using a Hewlett Packard 1050 unit with a fluorescence detector (HP Programmable Fluorescence Detector 1046 A). Statistical analysis The results were expressed as mean values ± SD. The Kolmogorov-Smirnov test was used to determine normal distribution. The intergroup data comparison was done using the Student’s t-test for independent variables with normal distribution or the data were compared by the Mann-Whitney test. Univariate analysis and multivariate analysis were performed to identify risk factors for an increased Hcy level. The relationships between the analyzed variables were assessed using the Spearman rank correlation test. The statistical significance of differences and correlations was determined by p values < 0.05. Statistical calculations were performed using MedCalc® software, version 9.3.7.0. Results Table 1 presents the characteristics of the groups. None of the investigated patients in inflammatory bowel diseases (IBD) groups and in the controls reported any thromboembolic events in past history. The UC and CD groups did not differ from the appropriate controls with respect to sex. Patients with CD were significantly younger than patients with UC and controls. However chi-square test confirmed that the groups are demographically homogenous. In the UC and CD group, the mean body mass index value was lower as compared to the controls (p = 0.03, p
