A study of effect of Vitamin D supplementation in Osteoarthritis patients

Introduction: Osteoarthritis (OA) is the common cause of musculoskeletal disability and pain. Osteoarthritis (OA) is a chronic disease characterized by a loss of articular cartilage and changes of the subchondral bone. Lower levels of vitamin D were associated with greater knee pain, poor quadriceps function with poor physical function. Several studies have documented that vitamin D supplementation increases muscle strength, improve physical performance, and decreases risk of falls among older people with low level of serum vitamin D. Materials &Methods: This present study was conducted at the outpatient clinic of the Department of Orthopedics at Maheswara Medical College & Hospital, Sangareddy during a February–December 2017 study period.The inclusion criteria were that the participants had symptomatic knee OA and low vitamin D status (25(OH)D < 30 ng/mL). Results: Data were analyzed using SPSS Statistics version 22 (SPSS, Inc., Chicago, IL, USA). Comparisonof baseline vs. post-vitamin Dsupplementation data was performed by paired t-test. One-way repeated-measurement ANOVA was used to test the time differences in muscle strength and physical performance. A p-value less than 0.05 for differences and the values were considered to be statistically signiﬁcant. Dominant grip strength (p = 0.01) and overall physical performance, such as gait speed (p < 0.001), TUGT (p < 0.001), STS (p < 0.001), and 6MWT (p < 0.001), signiﬁcantly improved after vitamin. Conclusion: Nevertheless, vitamin D supplementation is a safe and inexpensive way to improve muscle strength and physical function in this population. Based on these findings, we recommend vitamin D supplementation in knee OA patients that have poor physical function.


Introduction
Osteoarthritis (OA) is the common cause of musculoskeletal disability and pain. Osteoarthritis (OA) is a chronic disease characterized by a loss of articular cartilage and changes of the subchondral bone [1]. Knee is one of the most commonly affected joint. Several environmental factors including obesity, malalignment, trauma or joint instability have been associated with knee OA. Other symptoms of disease include joint pain, knee muscle wasting, and decreased range of motion, all of which lead to severe pain and disability in later life [2]. There are many risk factors that lead to early structural changes of the knee among healthy individuals. Vitamin D deficiency may play a role in the pathogenesis of OA. OA coexists frequently with vitamin D deficiency in elderly people. 63% of primary knee OA patients were found to have low vitamin D status worldwide. Lower levels of vitamin D were associated with greater knee pain, poor quadriceps function with poor physical function. Several studies have documented that vitamin D supplementation increases muscle strength, improves physical performance, and decreases risk of falls among older people with low level of serum vitamin D [3].
Normal bone and cartilage metabolism depend on presence of vitamin D. Vitamin D deficiency has adverse effects on calcium metabolism, osteoblastic activity, matrix ossification, bone density, and articular cartilage turnover. Vitamin D deficiency may lead to osteoarthritis via reducing the proteoglycan synthesis and increasing the metalloproteinase activity [4]. vitamin D (ergocalciferol) was used in this study for the investigationof the role of vitamin D supplementation on muscle strength and physical performance in knee OApatients with vitamin D insufficiency [5]. Given this disparity in the previous finding regarding vitamin D supplementation in Thailand, vitamin D2 (ergocalciferol) was used in this study for the investigation of the role of vitamin D supplementation on muscle strength and physical performance in knee OA patients with vitamin D insufficiency and deficiency.

Materials & Methods
Place of the study: This present study was conducted at the outpatient clinic of the Department of Orthopedics at Maheswara Medical College & Hospital, Sangareddy during a February-December 2017 study period.

Type of study: Observational study
Sampling method: Randomly selected Sample collection: One hundred and thirty-four patients with knee OA agreed to participate in the study.
Inclusion criteria: were that the participants had symptomatic knee OA and low vitamin D status (25(OH) D < 30 ng/mL). The diagnosis of osteoarthritis is based primarily on patient history, physical examination, and radiographic findings.
Exclusion Criteria: Exclusion criteria included history of knee surgery, primary hyperparathyroidism, rheumatoid or other inflammatory arthritis Statistical Method: Data were analyzed using SPSS Statistics version 20. Comparison of baseline vs. postvitamin Dsupplementation data was performed by paired t-test. One-way repeated-measurement ANOVA was used to test the time differences in muscle strength and physical performance.
A p-value less than 0.05 for differences and the values were considered to be statistically significant.
Written informed consent was obtained from all participants prior to their participation in the study. The Endocrine Society guidelines suggest that 50,000 IU of vitamin D 2 taken once a week for eight weeks is necessary to achieve the levels of serum 25(OH)D consistently above 30 ng/mL in adults. All participants were evaluated for knee pain using WOMAC and VAS evaluation instruments. VASscore is based on a 0-10 point scale, with a higher score indicating a higher level of pain. The participants were asked to put a mark on the line indicating their pain intensity at the present time in response to the following question: "If "0" is "no pain" and "10" is "the worst pain", where is your average pain intensity now on the visual analog score (VAS). Total WOMAC score represented the sum of three subscales, including pain, stiffness, and physical function. A higher WOMAC score indicates worse pain, more stiffness, and increased functional limitations.
At baseline of six months, muscle strength and physical performance were measured by physical therapists. Grip strength was assessed by grip strength dynamometer (Takei Scientific Instruments Co. Ltd., Tokyo, Japan) (kilograms). Knee extension force was measured by a handheld Micro FET 2 dynamometer (Hoggan Scientific LLC, Salt Lake City, UT, USA) (Newtons). The participant sat on the treatment table with knees flexed 90and the dynamometer was applied to the anterior part of the leg, 5 cm above the transmalleolar axis and perpendicular to the tibial crest. The participant raised their lower legs up and held against a maximum persistent force position (5 s) applied by a physical therapist. Four tests were used to evaluate physical performance. The first test was the 4-m gait speed test, which measures the time needed to walk four meters, calculated as meters per second [3]. The second test was the Timed Up and Go Test (TUGT), which measured the time needed to stand up from a chair, walk three meters, and return to the chair and sit down (seconds) 4 . The third test was the five times sit-to-stand test (STS), which recorded the time needed to perform five repeated chair stands without the use of arms (seconds) 5 . The last of the four tests was the six-minute walk test (6MWT), which measured the distance a patient could walk in six minutes (in meters).

Results
Data were analyzed using SPSS Statistics version 20. Comparison of baseline vs. post-vitamin Dsupplementation data was performed by paired t-test. One-wayrepeated-measurement ANOVA was used to test the time differences in muscle strength and physicalperformance. A p-value less than 0.05 for differences and the values were considered to be statistically significant.WOMAC scores did not change significantly between baseline and six months. However, VAS decreased significantly after treatment (p = 0.004) and the PCS of SF-12 improved significantly after supplementation treatment (p = 0.005).

Surgical Update: International Journal of Surgery & Orthopedics
Available online at: www.surgicalreview.in 92 | P a g e was small and the proportion of men was low, both of which prevented us from establishing the clinical relevance, particularly regarding changes in muscle strength.Third, we assayed markers of oxidative damage using plasma protein carbonyls that were not directly measured in skeletal muscle. Finally, 8.37% of patients were lost to follow-up. While this rate is higher than can be considered ideal, the loss to follow-up rate in the present study was lower than loss to follow-up rates reported from other studies.

Conclusions
In conclusion, our results suggest that 40,000 IU of vitamin D supplementation reduced oxidative protein damage, improved quality of life, and improved grip strength and physical performance. Accordingly, vitamin D treatment decreases current pain using VAS, but does not reduce pain during physical activity, as determined by WOMAC score.Vitamin D supplementation is a safe and inexpensive way to improve muscle strength and physical function in our population. Based on these findings, we can strongly recommend vitamin D supplementation in knee OA patients that have poor physical function.

Contribution by different authors during the study process-
The principal author involved in Conception or design of the work, Data collection, Data analysis and interpretation and co author involved in Drafting the articleCritical revision of the article.
Study adds to the existing knowledge-Vitamin D supplementation leads to reduced pain, stiffness or functional loss over a 3-year period. On the basis of these findings we consider that vitamin D supplementation has no role in the management of knee OA.