Factors Associated with Vitamin D Testing, Deficiency, Intake, and Supplementation in Patients with Chronic Pain

ABSTRACT

Vitamin D deficiency is a public health issue, with reports of six- to twenty-five–fold rise in vitamin D testing. Vitamin D deficiency has been linked to many chronic diseases such as diabetes mellitus, cardiovascular disease, depression, and chronic pain. Identifying factors associated with risk of deficiency in individuals with chronic pain will help minimize time and cost. This study aims to examine the factors associated with vitamin D testing, intake, and physician-advised supplementation in individuals with chronic pain. Using a cross-sectional design, data were collected from 465 individuals with chronic pain. These data were analyzed using penalized logistic regression with the LASSO technique. Fifty-seven percent reported being tested for vitamin D, about 40% reported being diagnosed with vitamin D deficiency, and of those who had been tested, 60% reported taking vitamin D supplementation. The findings suggest older age (OR 3.12, CI [1.02, 9.50]) and higher mean pain intensity score (OR 2.02, CI [1.13, 3.59]) increased an individual's chance of being vitamin D deficient. Unemployment or on leave due to pain (OR 1.79, [CI 1.03, 3.11]), part-time employment (OR 1.86, CI [1.02, 3.39]), and being a resident of Australia (OR 2.32, CI [1.13, 4.72]) increased chances of being tested for vitamin D. Being diagnosed with vitamin D deficiency (OR 6.67, CI [2.75, 16.19]), unemployed or on leave due to pain (OR 3.71, CI [1.25, 11.00]), and in part-time employment (OR 2.69, CI [0.86, 8.38]) were associated with physician-advised vitamin D supplementation. Our results may have practical implications, as identifying pretest risk factors may assist in identifying who is at risk of vitamin D deficiency, whom to test, and when to treat.

KEYWORDS:

• chronic pain
• supplements
• vitamin D
• vitamin D supplementation

Acknowledgments

The authors acknowledge all of the study participants who completed the study and the organizations and societies who promoted our survey on their websites.

Declaration of interest

MG, SV, and NS declare that they have no conflicts of interest. MNM is funded by John Lynch's NHMRC Australian Fellow funding (ID 478115). GLM has received support from Pfizer, Kaiser Permanente, USA; Workers' Compensation Boards in Australia, North America, and Europe; Agile Physiotherapy, USA; Results Physiotherapy, USA; the International Olympic Committee; and the Port Adelaide Football Club, Australia. He receives royalties for books on pain and rehabilitation, including two books that are cited in this article. He receives speaker fees for lectures on pain and rehabilitation. He is supported by a Principal Research Fellowship from the National Health and Medical Research Council of Australia.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Additional information

Notes on contributors

Manasi Gaikwad

Manasi Gaikwad is interested in vitamin D deficiency and its association with chronic painful conditions and the role of vitamin D supplementation as intervention.

Simon Vanlint

Simon Vanlint is interested in vitamin D, bone health, and health of marginalized groups.

G. Lorimer Moseley

G. Lorimer Moseley is interested in chronic pain, the role of brain and mind in chronic pain, and interventions that could help improve management.

Murthy N. Mittinty

Murthy N. Mittinty is interested in developing statistical methods in health research related to chronic pain, child cognitive development, and risk analysis.

Nigel Stocks

Nigel Stocks is interested in vitamin D and its role in chronic painful conditions.