Title

Vitamin D Supplementation in Knee Osteoarthritis
The Influence of Vitamin D Supplementation With and Without Glucosamine Sulfate and Omega-3 Fatty Acids in Patients With Osteoarthritis Symptoms
  • Phase

    N/A
  • Study Type

    Interventional
  • Status

    Completed No Results Posted
  • Study Participants

    73
Muscular (i.e., quadriceps) weakness is a major risk factor for predisposing the knee to osteoarthritis, impairing physical function, and increasing patient-reported pain. Muscular weakness is a consequence of and could contribute to the development of knee osteoarthritis. Minimizing muscular weakness has been fount to improve activities of daily living in patients with osteoarthritis symptoms. Although vitamin D associates with muscular strength in young and old populations, it is unknown if vitamin D supplementation improves muscular strength in subjects with osteoarthritis or osteoarthritis symptoms. It is also unknown if supplemental vitamin D alters circulating cytokine concentrations in subjects with knee osteoarthritis. Furthermore, it is probable that a more comprehensive supplement is necessary to improve muscular strength. Such as glucosamine sulfate and omega-3 fatty acids (i.e., eicosapentaenoic and docosahexaenoic acids) which could be influential on knee pain and inflammation as well as muscular strength. Therefore, the purpose of this study is to identify the influence of vitamin D supplementation with and without glucosamine sulfate and omega-3 fatty acids on circulating cytokine concentrations and muscular strength in subjects with knee osteoarthritis symptoms. This study is intended to establish preliminary data identifying the influence of vitamin D supplementation on circulating cytokines and muscular strength in subjects with osteoarthritis at no more than minimal risk exposure to subjects.
Knee osteoarthritis (OA) is a degenerative joint condition and a leading contributor to the global burden of disease. Estimates indicate that approximately 14 million people in the United States have symptomatic knee OA, and nearly half of those individuals are between 45 and 65 years of age. Over the years, data have extended our knowledge regarding the early premise of knee OA being the sole consequence of "wear and tear" processes of articular cartilage and it is now recognized that knee OA arises, in part, as a consequence of cytokine-mediated cellular and signaling events.

Cytokines are pleiotropic proteins instrumental to the immune response, host defenses, and intra- and inter-cellular signaling. Tumor necrosis factor (TNF)-α and interleukin (IL)-1β are pro-inflammatory cytokines that promote the catabolic and destructive events of knee OA in animal and human studies. These findings are corroborated by data illustrating chondrocytes as a site for pro-inflammatory cytokine production in knee OA, and that disease severity and progression associate with increasing TNF-α, IL-1β, and other cytokine concentrations in the circulation and transcriptional expression in peripheral blood leukocytes. Fortunately, IL-10 is an anti-inflammatory cytokine expressed in chondrocytes and possesses chondroprotective properties by inhibiting pro-inflammatory cytokine production. While some factors are unavoidable or unpreventable, such as aging, trauma, and genetic predisposition, disrupting the cytokine network could alter OA development and progression.

Low circulating vitamin D concentrations are reported in elderly with and without knee osteoarthritis symptoms. Serum 25(OH)D concentrations associate with muscular strength or performance in elderly. Vitamin D supplementation increases serum 25(OH)D concentrations and improves muscular strength in elderly. Based on these observations, vitamin D is essential for muscle function in elderly, however, it is unknown if supplemental vitamin D influences muscular strength in subjects with knee OA. Furthermore, it is probable that a more comprehensive supplement is necessary to improve muscular strength.

The aim of this study is to identify the influence of supplemental vitamin D on circulating cytokines and muscular strength in subjects with knee OA. This study consists of a double-blind, placebo-controlled experimental design. Subjects will be randomly assigned to one of three groups: (#1) vitamin D (cholecalciferol, 4000 IU) with glucosamine sulfate (1000 mg) and omega-3 fatty acids (eicosapentaenoic (EPA, 580 mg) and docosahexaenoic (DHA, 470 mg) acids), (#2) vitamin D (cholecalciferol, 4000 IU) with matching glucosamine sulfate and omega-3 fatty acid placebo supplements, or (#3) matching vitamin D, glucosamine sulfate and omega-3 fatty acid placebo supplements. Supplements will be taken daily for 84 days (12 weeks). Groups will be permutated in random blocks of six. Serum 25(OH)D, serum cytokines and muscular-based outcomes will be determined prior to, during, and following supplementation.
Study Started
Jul 28
2011
Primary Completion
Jan 08
2013
Study Completion
Jan 08
2013
Last Update
Oct 10
2019

Dietary Supplement Placebo

Placebo supplement for vitamin D (cholecalciferol), glucosamine sulfate, and omega-3 fatty acids. Supplement was taken orally every day for 84-days.

Dietary Supplement Vitamin D (cholecalciferol)

Vitamin D (cholecalciferol). Supplement was taken orally every day for 84-days.

Dietary Supplement Glucosamine sulfate and omega-3 fatty acids [glucosamine, omega-3 fatty acids (Omacor)]

Glucosamine sulfate and omega-3 fatty acids supplement was taken orally every day for 84-days.

Placebo Placebo Comparator

Matching vitamin D, glucosamine sulfate and omega-3 fatty acid placebo supplements. Supplements taken daily for 84 days (12 weeks).

Vitamin D Experimental

Vitamin D (cholecalciferol, 4000 IU) with matching glucosamine sulfate and omega-3 fatty acid placebo supplements. Supplements taken daily for 84 days (12 weeks).

Vitamin D, glucosamine sulfate, and omega-3 fatty acids Experimental

Vitamin D (cholecalciferol, 4000 IU) with glucosamine sulfate (1000 mg) and omega-3 fatty acids (eicosapentaenoic (EPA, 580 mg) and docosahexaenoic (DHA, 470 mg) acids). Supplements taken daily for 84 days (12 weeks).

Criteria

Inclusion Criteria:

Unilateral knee pain, weakness, and impaired physical activity
Older than 18 years of age but younger than 60 years of age
Reportedly physically active (minimum of 30 minutes of continuous exercise or physical exertion 3 times per week during the previous year)

Exclusion Criteria:

Bilateral symptoms of hip, knee or ankle osteoarthritis
Recent (within 2 years) surgery on the symptomatic or non-symptomatic limb
History of metabolic bone disease
History of any skeletal muscle pathologies
History of cardiac or peripheral cardiovascular system abnormalities
History of clotting disorders
History of coronary artery disease, peripheral vascular disease, or stroke
History of cancer
Use of warfarin or other anti-coagulants prior to study enrollment
Use of cholesterol lowering medication
History of high cholesterol or triglycerides
History of high blood pressure
Diagnosed with diabetes mellitus
Impaired liver function
Impaired kidney function
Pregnant
Daily dietary supplement or vitamin use during the previous year
Use of corticosteroid medication
Use of orlistat, phenobarbital, phenytoin, or thiazide
Morbidly obese (body mass index > 40 kg/m2)
No Results Posted