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 Table of Contents  
Year : 2022  |  Volume : 50  |  Issue : 4  |  Page : 260-266

Effect of vitamin D replacement therapy on laboratory parameters in hepatitis C virus cirrhotic patients

1 Department of Internal Medicine, Tanta University, Tanta, Egypt
2 Department of Clinical Pathology, Faculty of Medicine, Tanta University, Tanta, Egypt

Date of Submission04-May-2020
Date of Acceptance16-Jul-2022
Date of Web Publication22-May-2023

Correspondence Address:
Amira M Radwan
Department of Internal Medicine, Faculty of Medicine, Tanta University, 51 Asfour Street from Elgeesh Street, Kafr El-Zayat, El-Gharbya 31512
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/tmj.tmj_61_20

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Background Liver is a crucial organ for vitamin D metabolism, so vitamin D deficiency is prevalent in liver cirrhosis patients. Hepatitis C is also a global infective disease caused by hepatitis C virus (HCV) and chronic hepatitis leads to liver cirrhosis. Aim To evaluate vitamin D replacement therapy effect through laboratory parameters in HCV cirrhotic patients. Patients and methods Actual enrollment of 25 HCV cirrhotic patients (compensated and decompensated) with a 25(OH)D level of less than 30 ng/ml. All study population are subjected to be investigated at the baseline visit for 25(OH)D, ionized calcium, parathyroid hormone, complete blood count, random blood sugar, glycated hemoglobin (HbA1C), renal function tests, and liver function tests. Study participants received appointments for follow-up visits during the 12 weeks of vitamin D replacement therapy. Results After 3 months of vitamin D replacement therapy, the vitamin D level significantly improved (P=0.001), with significant increase in ionized calcium (P=0.001) and HbA1C (P=0.001). Vitamin D was significantly decreased as the Child score progressed from A to C (P=0.001). There was a significantly negative correlation among vitamin D level, Child score, and prothrombin time. However there was significant positive correlation among vitamin D level, platelet count, albumin, and ionized calcium. These correlations were before and after treatment. Conclusion In HCV cirrhotic patients, supplementation with vitamin D significantly increased 25(OH)D level and ionized calcium. Also, this was associated with improvement of HbA1C, but there was no significant effect on liver function parameters.

Keywords: cirrhosis, hepatitis C virus, laboratory, replacement therapy, vitamin D

How to cite this article:
Radwan AM, Tawfik MA, Nagy HM, Kotb NA. Effect of vitamin D replacement therapy on laboratory parameters in hepatitis C virus cirrhotic patients. Tanta Med J 2022;50:260-6

How to cite this URL:
Radwan AM, Tawfik MA, Nagy HM, Kotb NA. Effect of vitamin D replacement therapy on laboratory parameters in hepatitis C virus cirrhotic patients. Tanta Med J [serial online] 2022 [cited 2023 Sep 26];50:260-6. Available from: http://www.tdj.eg.net/text.asp?2022/50/4/260/377251

  Introduction Top

Vitamin D is known to be a fat-soluble vitamin, naturally it is present in few foods, normally synthesized in the skin under the effect of sunlight, and also available as dietary supplements [1]. It is a bone and calcium metabolism regulator [2]. It also controls many other cellular processes through the vitamin D receptor, which is widely expressed in nucleated cells [3]. Vitamin D has multiple extraskeletal effects, and its deficiency is considered risky for mortality and many chronic diseases, for example, hypertension, cardiovascular diseases, diabetes mellitus, asthma, and increase the risk of cancers (these effects may be secondary to its effect on cellular proliferation, differentiation, and apoptosis). [4]

Biologically, vitamin D is inactive and needs activation in the liver, then in the kidney to active l,25-dihydroxyvitamin D [5], so the liver works on vitamin D metabolism [6]. Liver cirrhosis is a late stage of progressive irreversible hepatic fibrosis, and hepatitis C virus (HCV) chronic infection is the most prevalent cause in Egypt [7,8]. The deficiency of vitamin D is highly prevalent with patients suffering chronic liver syndromes resulting from malnutrition, intestinal malabsorption of vitamin D due to portal hypertension, decreased sunlight exposure, low rate of vitamin D binding proteins, impaired vitamin D hepatic hydroxylation as well as increased vitamin D catabolism [6].

Vitamin D insufficiency is more prevalent in individuals with chronic liver illness than in the general population, according to a recent research. It was also shown that the prevalence of vitamin D deficiency rises as the liver disease advances [6,9]. We sought to derive the positive benefits of vitamin D supplementation from the connection between vitamin D and chronic liver disease (CLD).

Our study aimed to assess vitamin D replacement therapy effect through laboratory parameters for HCV cirrhotic patients.

  Patients and methods Top

Study design

Quasi-experimental clinical trial.

Ethical approval date and code number: 32451/07/18.

Study population

Patients included in the study were 25 HCV cirrhotic patients having a25(OH)D level of less than 30 ng/ml from inward, outpatient clinics of the Internal Medicine Department at Tanta University, from August 2018 till April 2019.

Inclusion criteria

  • (1) 25(OH)D level of less than 30 ng/ml (assessed at baseline visit).

  • (2) Decompensated and compensated HCV liver cirrhosis.

  • (3) Age from 18 till 75 years.

  • (4) Informed consent.

  • (5) Pregnancy test in childbearing potential women tested negative.

Exclusion criteria

  • (1) Hypercalcemia with serum ionized calcium more than 5.2 mg/dl.

  • (2) Liver cirrhosis due to other causes rather than HCV.

  • (3) Pregnant or lactating women.

  • (4) Intake of drugs as apart of other clinical studies.

  • (5) Glomerular filtration rate regarding the Modification of Diet in Renal Disease formula less than 15 ml/min/1.73 m2.

  • (6) Diseases with life expectancy below 1 year.

  • (7) Clinically acute illness requiring drug therapy.

  • (8) Radiation or chemotherapy treatment during the study.

  • (9) Regular intake of more than 800 IU of vitamin D through 4 weeks before research.

Ethical approval and informed consent

Tanta University’s Faculty of Medicine’s Local Research Ethics Committee accepted the research design. All patients provided written permission after being fully informed of the study’s advantages and hazards. The confidentiality of all participant’ data is ensured by a unique code number assigned to each patient file, which covers all investigations. The research posed no hazards to the participants as the examinations were noninvasive, except the possibility of infection during blood collection, which was eliminated entirely by using a septic method.

Data collection

The entire patients of the research had to present history including: age, sex, job, address, telephone number, medical history, and complete clinical tests. Serum 25(OH)D, serum ionized calcium, complete blood count, random blood sugar, glycated hemoglobin (HbA1C), blood urea, serum creatinine, estimated glomerular filtration rate, liver function tests [aspartate aminotransferase, alanine aminotransferase (ALT), serum bilirubin (total and direct), serum albumin, prothrombin time (PT), international normalized ratio], parathyroid hormone were all performed (it was evaluated only at baseline visit).

Investigations for the patients were done post screening for inclusion and exclusion criteria during baseline visit and study participants received appointments for the follow-up visits every month for three consecutive months. All study participants were allocated to receive once per month intramuscular injection of vitamin D3 (cholecalciferol 200 000 IU), we preferred to choose this way to ensure the intake of replacement dose on follow-up visits every month and also because CLD causes low intestinal absorption of vitamin D. Laboratory investigations were reevaluated after 3 months of vitamin D replacement therapy.

Blood sampling and processing: 8 ml of venous blood was collected from every patient after 8 h night fasting; 2 ml was added to EDTA for complete blood count. The needle of the syringe was allowed to pass gently along the wall of a clean dry centrifuge tube that was labeled with the patient’s name. The blood was allowed to coagulate for 30 min in a 37°C waterbath before being centrifuged for 15 min at 3000 rpm to separate serum using clean dry tubes. Serum sample was divided to two Eppendorf tubes, one of them sent to the lab to assay for renal, liver function tests, parathyroid hormone and ionized calcium, and the other was for the assessment of 25(OH)D level.

25(OH)D assay: by enzyme-linked immunosorbent assay kit.

The kit employs a double-antibody sandwich enzyme-linked immunosorbent assay to determine the amount of human (25(OH)D) in a sample of human serum. We added (25(OH)D) to a biotin-labeled monoclonal antibody enzyme incubated with streptavidin-HRP to create an immune complex, and then washed the immune complex to exclude the uncombined enzyme. Afterwards, we applied chromogen solution A, B, and the color of the liquid changed from blue to yellow as a result of the acid action. The chroma of hue and the content of the human material 25-dihydroxyvitamin D sample were shown to be favorably linked.

Statistical analysis

The data was input into a computer and analyzed using the IBM SPSS software program, version 20.0. (IBM Corporation, Armonk, New York, USA). Numbers and percentages were used to describe qualitative data. Range (minimum and maximum), mean, SD, and median were used to characterize quantitative data. The significance of the acquired findings was determined at the 5% level. The following tests were used: the χ2 test, the Monte-Carlo correction, the Student t test, the Pearson coefficient, the Mann–Whitney test, the Spearman coefficient, the F test (analysis of variance), and the Kruskal–Wallis test.

  Results Top

In our study, out of 30 HCV cirrhotic patients (compensated and decompensated) screened for 25(OH)D level, 27 of them who met the inclusion and exclusion criteria of our study, but actually 25 patients completed the baseline and follow-up visits, 10 (40%) males as well as 15 (60%) females with mean age (53.72 ± 13.04), and 16 of them were type 2 diabetes mellitus on insulin therapy. According to Child score 12 of them were of Child A score 48%, eight were of Child B score 32%, and five were of Child C score 20%.

There had been significant effect of vitamin D replacement therapy on 25(OH)D level with a mean treatment effect of 33.48 ± 2.46 ng/ml (P=0.001), a significant rise of ionized calcium with a mean treatment effect of 5.07 ± 0.19 mg/dl (P=0.001), significantly HbA1C decreased with a mean treatment effect (6.38 ± 1.21%) (P=0.034), while there were no significant effects on complete blood count parameters, renal function tests, or liver function tests (including bilirubin, albumin, SGPT, SGOT, PT, international normalized ratio) as demonstrated in [Table 1].
Table 1: Comparison between laboratory parameters before and after vitamin D replacement therapy

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Our study showed that before replacement therapy vitamin D level was significantly reduced as the Child score increased from A to C (P=0.001) as demonstrated in [Figure 1]. We discovered significant negative correlations of vitamin D level alongside PT and Child score, while there were significant positive correlations of vitamin D level alongside platelet count, serum albumin and ionized calcium; all these correlations were before and after replacement therapy as demonstrated in [Table 2] and [Table 3].
Figure 1: Comparison among Child A, B, and C scores regarding 25 (OH) vitamin D level before replacement therapy.

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Table 2: Correlation among vitamin D and various laboratory parameters before replacement therapy

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Table 3: Correlation among vitamin D and various laboratory parameters after replacement therapy

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[Table 4] shows multivariate analysis for the parameters affecting vitamin D level after replacement therapy, and Child score was the most independent factor affecting vitamin D level as demonstrated.
Table 4: Univariate and multivariate analyses for the parameters affecting 25(OH)vitamin D level after replacement therapy

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  Discussion Top

On the basis of results of previous studies which revealed that low vitamin D level is linked to CLDs [10,11], we want to search for the beneficial effect of its supplementation particularly in HCV cirrhotic patients. In our study, 27 patients of a total of 30 (90%) HCV cirrhotic patients first screened were deficient of vitamin D. According to new studies, vitamin D insufficiency and deficiency prevalence is more in patients suffering from chronic liver illness than in the general population ranging from 64 to 92% [9]. In the research conducted by Arteh et al. [9], the deficiency of vitamin D was detected in more than 90% of CLD patients, and a minimum of one third of them suffered severe deficiency. It has also been observed that the frequency of vitamin D insufficiency rises as the liver illness develops.

The present research discovered that vitamin D level was significantly less in Child C compared with Child B and Child A (P=0.001), and we also found significantly negative correlation among vitamin D and Child score (P=0.001). Moreover, univariant and multivariant analyses for parameters affecting vitamin D after replacement therapy showed that Child score was the most independent factor affecting 25(OH)D level. In a study by Fisher and Fisher which studied 100 consecutive outpatients with noncholestatic CLD, the prevalence of vitamin D deficiency was significantly increased in cirrhotic versus noncirrhotic patients (86.3 vs. 49.0%; P=0.0001). Moreover, the deficiency of vitamin D was more in cirrhotic patients with Child score class C than individuals with Child score class A [12].

Putz-Bankuti et al. [13] assessed vitamin D level of 75 CLD individuals and they were checked up through 3.6 years. Our findings discovered significant inverse correlations of 25(OH) D levels with the degree of liver function (MELD score and Child classification). The mean serum concentration of vitamin D in a prospective cohort study (n=251) by Finkelmeier et al. [14] was 8.93 7.1 ng/ml, with a range of 1.0–46.0 ng/ml. 25(OH)D levels varied across Child scores and exhibited a strong negative association with MELD score; furthermore, patients with decompensated cirrhosis and infectious comorbidities had slower 25(OH)D levels than individuals without problems.

Stokes et al. [6] addressed many processes producing vitamin D insufficiency in CLD, stating that less vitamin D levels result from both starvation and a lack of sunshine exposure. Furthermore, liver illness is characterized by poor intestinal absorption of vitamin D and less rates of binding proteins (DBP and albumin), which may transport vitamin D to the liver and kidney for activation. Furthermore, hepatic hydroxylation of vitamin D is hindered, resulting in low generation of active hormone and increased vitamin catabolism. Petta and colleagues discovered a reduction in 25(OH)D levels in a homogeneous group of individuals with a low incidence of F4 fibrosis.

Although there was a substantial reduction in 25(OH)D levels with increasing fibrosis stage, there was also a significant decline in the subgroup of patients with moderate fibrosis (F1), making it unlikely that less than 25(OH)D rates can be completely explained by reduced liver function. When noninvasive factors are taken into account, the area under the curve of the model that incorporates vitamin D rates to detect severe fibrosis stays excellent. This indicates that blood 25(OH)D can be used as a noninvasive measure of liver fibrosis, a usage that has to be investigated and confirmed in big prospective cohort studies in those suffering from chronic hepatitis C of all genotypes, as well as CLD from other causes [15].

Given the importance of the liver in vitamin D metabolism, it was nevertheless essential to determine if and to what degree vitamin D supplementation raises serum 25(OH)D concentration for cases of cirrhosis, as well as its impact on laboratory markers. In our study 25(OH)DD rate significantly elevated after a 3-month-therapy of vitamin D3 replacement (P=0.001). Rode and colleagues found that vitamin D deficiency increases with oral vitamin D supplements and the level falls without supplements; 25(OH)D level was elevated by 60.0% (119.11 ± 13.20 nmol/l) in those having deficiency after vitamin D replacement therapy and reduced by 25.2% (−18.33 ± 12.02 nmol/l) in uncured initially replete patients by more than a median of 4 months, and they also reported that vitamin D rate correlated with that of albumin as the present research has discovered in the positive correlation among albumin and vitamin D (P=0.039) [11].

Also Pilz et al. [16] found that supplementation of vitamin D elevated 25(OH)D serum concentrations when 36 consecutive cirrhotic patients with 25(OH)D concentrations of less than 30 ng/ml were randomly allocated to receive 2800 IU of vitamin D3 every day. The current research discovered a significant rise of ionized calcium after vitamin D3 replacement therapy (P=0.001); increased level of serum ionized calcium and vitamin D might have its positive reflection on hepatic osteodystrophy as demonstrated in several studies [17],[18],[19]. The cross-sectional research of Chinnaratha and colleagues investigated 406 patients, of Child score A or B with a median model for end-stage liver illness score of 11 (5–40), prevalence of hepatic osteodystrophy and vitamin D deficiency (≤50 nmol/l) was 56 and 54%, respectively, and earlier fractures took place with 3% and concluded that there was a great prevalence of hepatic osteodystrophy and vitamin D deficiency in cirrhotic patients at presentation regardless of the severity of disease or etiology [17].

Bouillon et al. [18], discovered that vitamin D deficiency (serum 25-hydroxyvitamin D <50 nmol/l) accelerates bone turnover, bone loss, and osteoporotic fractures. Chen et al. [19] discovered significant correlation among lumbar spine bone marrow density and 25(OH)D level in cirrhotic patients compared with healthy normal controls. Also, serum 25(OH)D was a strong independent predictor on hip bone density in cirrhotic patients. In our study after vitamin D replenishment, HbAlC had significantly decreased (P=0.034). Kawaguchi et al. [20] showed that there is a strong association between CLD and increased insulin resistance and is responsible for the pathogenesis of what is called hepatogenous diabetes, distinctive factors such as hepatic parenchymal damage, portosystemic shunt as well as HCV result in hepatogenous insulin resistance.

Lemieux et al. [21] showed that individuals at high risk of diabetes or with newly diagnosed type 2 diabetes with vitamin D supplementation for 6 months significantly increased peripheral insulin sensitivity and β-cells. The Nwosu and Maranda retrospective study was conducted on 131 participants suffering from either T1D or T2D. All patients suffered diabetes for more than 12 months, got vitamin D to cure vitamin D deficiency, and had baseline as well as immediate tests of HbA1C, 25(OH)D, and ALT. Vitamin D insufficiency was found in 72.1% of T2D patients and 37.5%of T1D patients at baseline (P=0.001). When compared with T1D patients, T2D patients exhibited greater BMI (P=0.001), ALT (P=0.001), yet less 25(OH)D (P=0.001), and no change in HbA1C (P=0.94), or total daily dosage of insulin per kg body weight (P=0.48) values.

There was a substantial increase in 25(OH)D in both T2D (P=0.015) and T1D patients (P=0.001) after 3 months of vitamin D treatment, but not in T1D. There was also a significant reduction in BMI (P=0.015) and ALT (P=0.012) in T2D, yet not in T1D. HbA1C decreased significantly in T2D from 8.52.9% at baseline to 7.72.5% at 3 months, but not in T1D (8.51.2–8.531.1%) [22].

Also, Takiishi et al. [23] showed that in type 2 diabetes mellitus, supplementation of vitamin D increases insulin sensitivity and decreases inflammation. The present research discovered positive correlation among vitamin D level and albumin before and after vitamin D3 replacement therapy. Bikle et al. [24] concluded that 25(OH)D travel in blood bound to DBP and albumin, so alterations in DBP concentrations and albumin alter 25(OH)D rate in serum. In our study, we discovered no significant impact of vitamin D replacement on liver function tests, urea, creatinine, and complete blood count.

A randomized controlled trial research by Pilz and colleagues was conducted on 36 consecutive patients suffering from liver cirrhosis and 25(OH)D deficiency wanting to assess whether vitamin D supplements in cirrhotic patients is efficient at raising 25(OH)D level with secondary outcome measures that involved hepatic function exanimations. They found that supplementation of vitamin D resulted in no significant impact on hepatic function tests [16].

  Conclusion Top

We showed in our study that screening for vitamin D level in cirrhotic patients is essential because vitamin D deficiency and insufficiency prevalence is high in CLD patients and supplementation of vitamin D increases serum 25(OH)D concentrations in HCV cirrhosis patients.

Conflicts of interest

There are no conflicts of interest.

  References Top

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Nwosu BU, Maranda L The effects of vitamin D supplementation on hepatic dysfunction, vitamin D status, and glycemic control in children and adolescents with vitamin D deficiency and either type 1 and type 2 diabetes mellitus. PLoS ONE 2014; 9: e99646.  Back to cited text no. 22
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  [Figure 1]

  [Table 1], [Table 2], [Table 3], [Table 4]


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