Vitamin D Deficiency and Pain: Clinical Evidence of Low Levels of Vitamin D and Supplementation in Chronic Pain States
Pain and Therapy, April 2015, 29 Apr 2015
Elspeth E. Shipton, Edward A. Shipton firstname.lastname@example.org
A majority of the studies found that an identical dose of Vitamin D relieved pain, even though they ignored the fact that obese, elderly, people with some diseases,those with dark skin, etc.(high risk) need more vitamin D than others.
Only those studies which used too little of vitamin D3 or used vitamin D2 found no benefit (no surprise).
They did not consider those studies which used vitamin D too infrequently to make a difference
See also VitaminDWiki
Overview Pain and Vitamin D
Pain - chronic category has the following
- Overview Pain and Vitamin D
- Overview Fibromyalgia or Chronic Fatigue and vitamin D
- Overview Rheumatoid Arthritis and vitamin D
- Shingles and vitamin D
- Shin splints decrease with vitamin D
- Migraine and Vitamin D
- Headache category
- "musculoskeletal pain" 374 items as of March 2018
- "chronic fatigue" 185 items as of Jan 2017
- Category Back Pain
- 5 pain studies in VitaminDWiki with KNEE in the title as of Feb 2022 (see below)
- Opioid OR Opiate OR Morphine in the title 10 pages as of June 2021
The TOP articles in Pain and Vitamin D are listed here:
- Magnesium reduces pain - many studies
- Less labor pain if higher level of vitamin D – August 2021
- Low Level Laser Therapy greatly increased Vitamin D and Magnesium (for diabetics with nephropathy) – March 2019
- Fibromyalgia pain substantially reduced by weekly Vitamin D (50,000 IU) – June 2018
- Trigger points (myofascial pain) may be associated with low Vitamin D and low Magnesium – Jan 2018
- Fibromyalgia treated with Vitamin D (50,000 IU weekly for 3 months) – 2016, 2017, 2018, 2019
- Fibromyalgia pain reduced with vitamin D intervention that achieved 30-48 ng – RCT Feb 2014
- Vitamin D at CureTogether: Fibromyalgia, MS, Psorasis, etc - Dec 2013
- 7 improvements in lives of veterans with chronic pain with 50,000 IU vitamin D weekly – June 2012
Pages listed in BOTH the categories Darker Skin and Pain
- Vitality recaptured with Vitamin D (stories of Swedish immigrant women in this case) – Dec 2019
- Pain following auto accident is worse if low vitamin D (for African Americans) – April 2015
- Dark skinned in Norway: 1000 IU vitamin D not enough to reduce pain – RCT Sept 2014
- Most immigrant women in Sweden had little vitamin D and lots of muscle pain – May 2013
- Sleep disorder and nonspecific pain implies low vitamin D, especially if dark skin – March 2013
- 150,000 IU vitamin D reduced pain in immigrants – RCT Dec 2012
- Blacks had lower vitamin D and more quantifiable pain than whites with knee osteoarthritis – Nov 2012
A number of studies suggest a link between low levels of 25-hydroxy vitamin D and incidence of acute and chronic pain. Clinical studies of vitamin D supplementation in patients with known vitamin D deficiency have shown mixed results in improving pain scores.
In this article, vitamin D deficiency risk factors are observed and adequate levels of 25-hydroxy vitamin D defined. Clinical supplementation with vitamin D is explored, including the schedules used in published clinical trials. Evidence of the effectiveness of vitamin D supplementation for the treatment of chronic pain conditions from double-blind randomized controlled trials (RCTs) is examined.
The scientific evidence for vitamin D as a treatment option for chronic pain is limited due to lack of RCTs. It cannot be stated conclusively that vitamin D deficiency is directly linked to the etiology or maintenance of chronic pain states.
There remains a growing body of both clinical and laboratory evidence pointing to a potential relationship between low levels of 25-hydroxy vitamin D and a variety of chronic pain states. More focused research involving large RCTs is necessary.
Evaluation of clinical studies regarding the use of vitamin D for the treatment of chronic pain was previously undertaken in 2008 . The authors searched MEDLINE (PubMed) using various search terms for vitamin D and pain prior to September 2008. Twenty-two relevant studies were identified that reported mean 25(OH)D levels and/or investigated the results of vitamin D treatment in patients with chronic pain conditions.
- Only five of these studies were randomized double-blind trials of vitamin D treatment.
- Vitamin D treatments involved monthly equivalent doses between 1200 and 400,000 IU.
- Fourteen studies were in musculoskeletal pain,
- five in chronic widespread pain or fibromyalgia,
- one in diabetic subjects with neuropathic pain,
- one addressing an unusual hyperaesthetic pain syndrome, and
- one in various conditions.
Duration of treatment was from a few days to 12 months, although most studies lasted 2 months or more. Treatment studies involved 733 patients. Randomized double-blind trials involved 229 patients, of whom only 22 (10%) were in a trial with a significant improvement in pain with vitamin D, and then only on a pain mobility measure; 207 patients were involved in trials with no significant improvement in pain with vitamin D. There was also no apparent correlation between significant improvement in pain with vitamin D and with a particular preparation, dose, or condition. There was no persuasive evidence of lower levels of 25(OH)D in those with chronic pain than in the control populations. There was a striking contrast in treatment effects between randomized, doubleblind trials that minimized bias and those with designs known to be subject to bias. In the former, only 10% of patients were in trials showing a benefit of vitamin D treatment; in the latter, 93% were in trials showing a benefit of vitamin D treatment . This study highlighted the need for further randomized double-blind placebo-controlled trials.
A Cochrane review of randomized doubleblind trials of vitamin D supplementation compared with placebo was published in 2010 . The aim was to determine the efficacy of vitamin D in the treatment of chronic pain conditions. Only four studies (with a total of 294 participants) were included; eleven trials were excluded due to poor methodological design, or because not all participants received a clearly defined chronic pain diagnosis . The studies included were similar in quality, used analogous chronic pain conditions with comparable outcome measures [91, 96, 99, 100]. Patients were supplemented with varying amounts and formulations of vitamin D for periods ranging from 16 weeks to 12 months. In summary, out of the four trials reviewed, the benefit of using vitamin D in chronic pain treatment was only shown in one trial. In the other three trials, there was no significant beneficial effect of vitamin D over placebo. Adverse effects of treatment were infrequent, and occurred at the same rates in vitamin D and placebo groups [96, 100].
Our study concurs with the results of the previous review on the subject published in 2009 and the Cochrane review published in 2010, in that there is insufficient high-quality evidence for a definitive effect of vitamin D in chronic pain. However, a trend appears in a positive direction indicating a beneficial effect of vitamin D over placebo in chronic pain.
The number of randomized placebo- controlled double-blind studies is increasing which is encouraging. Six of the RCTs included in our study were published since 2011. Although the search strategy of this comprehensive review was thorough, it is possible that some randomized clinical trials might not have been located. A positive publication bias cannot be excluded as journals are reluctant to publish negative results. The overall picture generated by a review of this type could thus be a false positive.
Studies using visual analog scale (VAS) pain scores as the primary or solitary outcome measure have shown mixed results in chronic pain patients when evaluating the impact of vitamin D supplementation in this condition [82, 91, 101-103]. Significant improvements in assessment of sleep, mood, pain levels, wellbeing, and various aspects of quality of life with vitamin D supplementation have been shown [82, 104-107]. Whilst there is a growing body of both clinical and laboratory evidence pointing to a potential relationship between low levels of 25(OH)D and chronic pain, it is not possible to state conclusively that vitamin D deficiency is directly linked to the etiology or maintenance of chronic pain states. The scientific evidence for the use of vitamin D as a treatment option for chronic pain is limited at present due to low-quality designs, and due to the lack of RCTs.
A number of questions remain with regard to supplementation of vitamin D in patients with chronic pain. Vitamin D metabolism and action needs to be further elucidated including extra- renal activation and catabolism, distribution and mobilization from body pools, and its interaction with relevant genetic polymorphisms . There remains some debate over the precise definition of vitamin D deficiency or insufficiency based on the serum levels of 25(OH)D. The influence of age and body weight on the variability of the response of serum levels of 25(OH)D to intake needs to be clarified . More focused research is necessary involving larger double-blind RCTs. These need to be stratified by baseline 25(OH)D levels, type of pain, and the use of adequate doses of vitamin D based on serum levels. More research is necessary to determine whether or not the effect of vitamin D supplementation is limited to patients who are vitamin D deficient. The optimal dose and length of time needed for supplementation need to be assessed as well.
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