TABLE 4.

Studies Investigating Increased Vitamin D Serum Levels as a Way to Decrease the Risk for Osteoarthritis (OA)

Authors	Study Design	Sample	Vitamin D Serum Level Measurements	Findings
Hussain et al23	Prospective cohort	9135 adults older than 40 years who were undergoing hip arthroplasty for OA	Quartile 1: ≤41 nmol/L Quartile 2: ≥42 and ≤54 nmol/L Quartile 3: ≥55 and ≤69 nmol/L Quartile 4: ≥70 nmol/L	Increasing serum vitamin D levels was associated with increased risk of hip arthroplasty in men. No significant difference was found in women
Jin et al25	Randomized controlled trial	413 patients with low vitamin D serum levels (12.5-60 nmol/L) were enrolled in the study. A total of 209 patients received oral vitamin D3 (50,000 IU) and 204 patients received identical placebos	No vitamin D sufficiency levels were established	Monthly treatment with oral vitamin D did not produce significant clinical or cartilage volume structural differences in vitamin D–deficient knee OA cases over time. Results did not support vitamin D supplementation
Arden et al4	Double-blind, randomized placebo-controlled trial	474 patients aged older than 50 years with radiographically evident knee OA were given either 800 IU cholecalciferol daily or placebo	Vitamin D deficiency <10 ng/mL Vitamin D insufficiency = 10.1-20.0 ng/mL Vitamin D sufficient ≥20 ng/mL	There was no significant difference in rate of joint space narrowing in the medial compartment of knees due to vitamin D supplementation