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. 2021 Aug 25;8(8):CD011564.
doi: 10.1002/14651858.CD011564.pub3.

Vitamin D supplementation for chronic liver diseases in adults

Milica Bjelakovic  1 , Dimitrinka Nikolova  2 , Goran Bjelakovic  1   2   3 , Christian Gluud  4   5   6
Affiliations

Vitamin D supplementation for chronic liver diseases in adults

Milica Bjelakovic et al. Cochrane Database Syst Rev. .

Abstract

Background: Vitamin D deficiency is often reported in people with chronic liver diseases. Improving vitamin D status could therefore be beneficial for people with chronic liver diseases.

Objectives: To assess the beneficial and harmful effects of vitamin D supplementation in adults with chronic liver diseases.

Search methods: We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE Ovid, Embase Ovid, LILACS, Science Citation Index Expanded, and Conference Proceedings Citation Index-Science. We also searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform. We scanned bibliographies of relevant publications and enquired experts and pharmaceutical companies as to additional trials. All searches were up to November 2020.

Selection criteria: Randomised clinical trials that compared vitamin D at any dose, duration, and route of administration versus placebo or no intervention in adults with chronic liver diseases. Vitamin D could have been administered as supplemental vitamin D (vitamin D3 (cholecalciferol) or vitamin D2 (ergocalciferol)), or an active form of vitamin D (1α-hydroxyvitamin D (alfacalcidol), 25-hydroxyvitamin D (calcidiol), or 1,25-dihydroxyvitamin D (calcitriol)).

Data collection and analysis: We used standard methodological procedures expected by Cochrane. We used GRADE to assess the certainty of evidence.

Main results: We included 27 randomised clinical trials with 1979 adult participants. This review update added 12 trials with 945 participants. We assessed all trials as at high risk of bias. All trials had a parallel-group design. Eleven trials were conducted in high-income countries and 16 trials in middle-income countries. Ten trials included participants with chronic hepatitis C, five trials participants with liver cirrhosis, 11 trials participants with non-alcoholic fatty liver disease, and one trial liver transplant recipients. All of the included trials reported the baseline vitamin D status of participants. Participants in nine trials had baseline serum 25-hydroxyvitamin D levels at or above vitamin D adequacy (20 ng/mL), whilst participants in the remaining 18 trials were vitamin D insufficient (less than 20 ng/mL). Twenty-four trials administered vitamin D orally, two trials intramuscularly, and one trial intramuscularly and orally. In all 27 trials, the mean duration of vitamin D supplementation was 6 months, and the mean follow-up of participants from randomisation was 7 months. Twenty trials (1592 participants; 44% women; mean age 48 years) tested vitamin D3 (cholecalciferol); three trials (156 participants; 28% women; mean age 54 years) tested vitamin D2; four trials (291 participants; 60% women; mean age 52 years) tested 1,25-dihydroxyvitamin D; and one trial (18 participants; 0% women; mean age 52 years) tested 25-hydroxyvitamin D. One trial did not report the form of vitamin D. Twelve trials used a placebo, whilst the other 15 trials used no intervention in the control group. Fourteen trials appeared to be free of vested interest. Eleven trials did not provide any information on clinical trial support or sponsorship. Two trials were funded by industry. We are very uncertain regarding the effect of vitamin D versus placebo or no intervention on all-cause mortality (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.51 to 1.45; 27 trials; 1979 participants). The mean follow-up was 7 months (range 1 to 18 months). We are very uncertain regarding the effect of vitamin D versus placebo or no intervention on liver-related mortality (RR 1.62, 95% CI 0.08 to 34.66; 1 trial; 18 participants) (follow-up: 12 months); serious adverse events such as hypercalcaemia (RR 5.00, 95% CI 0.25 to 100.8; 1 trial; 76 participants); myocardial infarction (RR 0.75, 95% CI 0.08 to 6.81; 2 trials; 86 participants); thyroiditis (RR 0.33, 95% CI 0.01 to 7.91; 1 trial; 68 participants); circular haemorrhoidal prolapse (RR 3.00, 95% CI 0.14 to 65.9; 1 trial; 20 participants); bronchopneumonia (RR 0.33, 95% CI 0.02 to 7.32; 1 trial 20 participants); and non-serious adverse events. The certainty of evidence for all outcomes is very low. We found no data on liver-related morbidity such as gastrointestinal bleeding, hepatic encephalopathy, hepatorenal syndrome, ascites, or liver cancer. There were also no data on health-related quality of life. The evidence is also very uncertain regarding the effect of vitamin D versus placebo or no intervention on rapid, early, and sustained virological response in people with chronic hepatitis C.

Authors' conclusions: Given the high risk of bias and insufficient power of the included trials and the very low certainty of the available evidence, vitamin D supplementation versus placebo or no intervention may increase or reduce all-cause mortality, liver-related mortality, serious adverse events, or non-serious adverse events in adults with chronic liver diseases. There is a lack of data on liver-related morbidity and health-related quality of life. Further evidence on clinically important outcomes analysed in this review is needed.

PubMed Disclaimer

Conflict of interest statement

MB: none known. DN is the Managing Editor of the Cochrane Hepato‐Biliary Group. However, the peer review process was dealt with through staff within the Cochrane Central Editorial Service Team. GB: none known. CG: none known.

Figures

1
1
Study flow diagram.
2
2
Risk of bias summary: review authors' judgements about each risk of bias item for each included study.
3
3
Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.
4
4
All‐cause mortality. Trial Sequential Analysis was performed based on a mortality in the control group of 2%, a relative risk reduction of 20% in the experimental intervention group, a type I error of 1.25%, and a type II error of 10% (90% power). There was no diversity. The required information size was 63,116 participants. The cumulative Z‐curve (blue line) did not cross the trial sequential monitoring boundary for benefit or harm after the 27th trial. The trial sequential monitoring boundaries were ignored due to little information (3.14%). The blue line represents the cumulative Z‐score of the meta‐analysis. The green dotted lines represent the conventional statistical boundaries.
5
5
Rapid virological response. Trial Sequential Analysis was performed based on a failure of rapid virological response in the control group of 53%, a relative risk reduction (RRR) of 20% in the intervention group, a type I error of 1.25%, and a type II error of 10% (90% power). There was no diversity. The required information size was 1269 participants. The cumulative Z‐curve (blue line) crossed the conventional monitoring boundary for benefit but did not cross the trial sequential monitoring boundary for benefit (red down‐sloping line). The blue line represents the cumulative Z‐score of the meta‐analysis. The green dotted lines represent the conventional statistical boundaries. The red inward‐sloping lines represent the trial sequential monitoring boundaries.
6
6
Early virological response. Trial Sequential Analysis was performed based on failure of early virological response in the control group of 34%, a relative risk reduction of 20% in the intervention group, a type I error of 1.25%, and a type II error of 10% (90% power). The diversity was 88%. The required information size was 21,306 participants. The cumulative Z‐curve (blue line) crossed the conventional monitoring boundary for benefit. The trial sequential monitoring boundary was ignored due to little information (1.48%). The blue line represents the cumulative Z‐score of the meta‐analysis. The green lines represent the conventional statistical boundaries.
7
7
Sustained virological response. Trial Sequential Analysis was performed based on failure of sustained virological response in the control group of 48%, a relative risk reduction (RRR) of 20% in the intervention group, a type I error of 1.25%, and a type II error of 10% (90% power). Diversity was 80%. The required information size was 7570 participants. The cumulative Z‐curve (blue line) crossed the conventional monitoring boundary for benefit. However, it did not cross any of the monitoring boundaries for benefit, harm, or futility. The blue line represents the cumulative Z‐score of the meta‐analysis. The green lines represent the conventional statistical boundaries. The red inward‐sloping lines represent the trial sequential monitoring boundaries for benefit and harm.
1.1
1.1. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 1: 1.1 All‐cause mortality
1.2
1.2. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 2: 1.1 All‐cause mortality according to vested interest
1.3
1.3. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 3: All‐cause mortality according to vitamin D status at entry
1.4
1.4. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 4: All‐cause mortality according to form of vitamin D
1.5
1.5. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 5: All‐cause mortality (best‐worst‐case and worst‐best‐case scenarios)
1.6
1.6. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 6: Liver‐related mortality
1.7
1.7. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 7: Serious adverse events
1.8
1.8. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 8: Liver‐related morbidity
1.9
1.9. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 9: Health‐related quality of life
1.10
1.10. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 10: Non‐serious adverse events
1.11
1.11. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 11: Failure of rapid virological response
1.12
1.12. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 12: Failure of early virological response
1.13
1.13. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 13: Failure of sustained virological response
1.14
1.14. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 14: Acute cellular rejection in liver transplant recipients
1.15
1.15. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 15: Vitamin D status (ng/mL)
1.16
1.16. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 16: Bone mineral density (g/cm)
1.17
1.17. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 17: Aspartate aminotransferase (IU/L)
1.18
1.18. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 18: Alanine aminotransferase (IU/L
1.19
1.19. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 19: Alkaline phosphatases (IU/L)
1.20
1.20. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 20: Gamma‐glutamyl transpeptidase (IU/L)
1.21
1.21. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 21: Bilirubin (mg/dL)
1.22
1.22. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 22: Triglyceride (mg/dL)
1.23
1.23. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 23: Cholesterol (mg/dL)
1.24
1.24. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 24: LDL cholesterol (mg/dL)
1.25
1.25. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 25: Albumin (g/L)
1.26
1.26. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 26: HDL cholesterol (mg/dL)
1.27
1.27. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 27: Calcium (mg/dL)
1.28
1.28. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 28: Glucose (mg/dL)
1.29
1.29. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 29: Phosphorus (mg/dL)
1.30
1.30. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 30: Adiponectin (µg/mL)
1.31
1.31. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 31: Insulin (mIU/mL)
1.32
1.32. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 32: Parathyroid hormone (pg/mL)
1.33
1.33. Analysis
Comparison 1: Vitamin D versus placebo or no intervention, Outcome 33: C‐reactive protein (mg/L)
See this image and copyright information in PMC

Update of

References

References to studies included in this review

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Lorvand Amiri 2016 {published data only}
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Nimer 2012 {published data only}
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Pilz 2016 {published data only}
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Sakpal 2017 {published data only}
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Sharifi 2014 {published data only}
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Vosoghinia 2016 {published data only}
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References to studies excluded from this review

Atsukawa 2013 {published data only}
    1. Atsukawa M, Tsubota A, Shimada N, Kondo C, Itokawa N, Nakagawa A, et al. Efficacy of alfacalcidol on PEG-IFN/ribavirin combination therapy for elderly patients with chronic hepatitis C: a pilot study. Hepatitis Monthly 2013;13(12):e14872. - PMC - PubMed
Benetti 2008 {published data only}
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Bitetto 2010 {published data only}
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Chen 2015 {published data only}
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Dasarathy 2017 {published data only}
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Fernández Fernández 2016 {published data only}
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Hasanain 2018 {published data only}
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Kitson 2016 {published data only}
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Kondo 2013 {published data only}
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Long 1978 {published data only}
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Malham 2012 {published data only}
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Naderpoor 2018 {published data only}
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Omori‐Mizuno 2015 {published data only}
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Papapostoli 2016 {published data only}
    1. Papapostoli I, Lammert F, Stokes CS. Effect of short-term vitamin D correction on hepatic steatosis as quantified by controlled attenuation parameter (CAP). Journal of Gastrointestinal and Liver Diseases 2016;25(2):175-81. - PubMed
Park 2017 {published data only}
    1. Park D, Kwon H, Oh SW, Joh HK, Hwang SS, Park JH, et al. Is vitamin D an independent risk factor of nonalcoholic fatty liver disease?: a cross-sectional study of the healthy population. Journal of Korean Medical Science 2017;32(1):95-101. - PMC - PubMed
Rode 2010 {published data only}
    1. Rode A, Fourlanos S, Nicoll A. Oral vitamin D replacement is effective in chronic liver disease [Fréquence du déficit en vitamine D et effet de la supplémentation orale au cours des maladies chroniques du foie]. Gastroentérologie Clinique et Biologique 2010;34(11):618-20. - PubMed
Stokes 2016 {published data only}
    1. Stokes CS, Grünhage F, Baus C, Volmer DA, Wagenpfeil S, Riemenschneider M, et al. Vitamin D supplementation reduces depressive symptoms in patients with chronic liver disease. Clinical Nutrition (Edinburgh, Scotland) 2016;35(4):950-7. - PubMed
Tavakoli 2019 {published data only}
    1. Tavakoli H, Rostami H, Avan A, Bagherniya M, Ferns GA, Khayyatzadeh SS. High dose vitamin D supplementation is associated with an improvement in serum markers of liver function. Biofactors 2019;45(3):335-42. - PubMed
Terrier 2015 {published data only}
    1. Terrier B, Lapidus N, Pol S, Serfaty L, Ratziu V, Asselah T, et al. Vitamin D in addition to peg-interferon-alpha/ribavirin in chronic hepatitis C virus infection: ANRS-HC25-VITAVIC study. World Journal of Gastroenterology 2015;21(18):5647-53. - PMC - PubMed
Zhou 2019 {published data only}
    1. Zhou Q, Li L, Chen Y, Zhang J, Zhong L, Peng Z, et al. Vitamin D supplementation could reduce the risk of acute cellular rejection and infection in vitamin D deficient liver allograft recipients. International Immunopharmacology 2019;75:105811. - PubMed

References to ongoing studies

IRCT2016020326342N1 {published data only}
    1. IRCT2016020326342N1. Effectiveness of vitamin D supplementation on severity of cirrhosis based on CHILD and MELD scores in patients with decompensate cirrhosis. en.irct.ir/trial/21847 (first received 28 February 2016).
NCT02779465 {published data only}
    1. NCT02779465. Oral vitamin D treatment for the prevention of hepatocellular carcinoma (VDHCC). clinicaltrials.gov/ct2/show/NCT02779465 (first received 20 May 2016).

Additional references

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References to other published versions of this review

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