Hip Arthroplasty and Vitamin D Status

Study Overview
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Brief Summary
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It is essential that serum 25(OH)D changes following surgery be clarified, and the mechanism(s) underpinning these changes be identified. As such, the overarching hypothesis of this study is that elective total hip arthroplasty reduces serum total 25(OH)D.

Official Title
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Hip Arthroplasty and Vitamin D Status

Conditions
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Vitamin D Deficiency

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Elective total hip arthroplasty for osteoarthritis Age 50+ Able and willing to sign informed consent English speaking Willing to not alter vitamin D supplementation use for the duration of this study Willing to utilize sunscreen of SPF-15 or higher when sun exposure for more than 15 minutes is expected Exclusion Criteria: Illnesses known to affect inflammatory marker status including, but not limited to, rheumatoid arthritis, systemic lupus erythematosis and mixed connective tissue disease Chronic diseases that could potentially affect DBP status, e.g., chronic kidney disease stage requiring dialysis, nephrotic syndrome and chronic hepatitis, Hip arthritis from causes other than osteoarthritis Treatment with medications with potential to affect vitamin D metabolism, (e.g., phenytoin, phenobarbital, teriparatide or active vitamin D analogues) or to potentially interfere with 25(OH)D measurement by HPLC (atavaquone) within the preceding three months. Treatment with high dose vitamin D supplementation (50,000 IU weekly or more frequently) within the preceding three months. Note; subjects on a stable daily vitamin D dose will be allowed to participate Surgical procedure within the preceding six months Use of tanning beds or salons or unwillingness to utilize sunscreen during periods of sun exposure of 15 minutes or longer

Ages Eligible for Study
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Minimum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Adults undergoing total hip arthroplasty<br>No intervention will be administered, this is an observational trial. The study population includes adults 50+ who are undergoing elective total hip arthroplasty for osteoarthritis. | Other: No intervention<br>* There are no interventions. This is an observational trial.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in total 25(OH)D |  | Measured at the pre-operative visit on the day of surgery, post-operative visit (on average 1 to 2 days after surgery), and 6 weeks post-operative visit | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| DBP (vitamin D binding protein) in serum and urine will be evaluated for 25(OH)D degradation after surgical intervention. | We will evaluate if free 25(OH)D varies over the peri-operative time period. We will evaluate whether the total 25(OH)D change is related to reduced serum DBP and/or increased urinary DBP excretion. We will also correlate the change in free 25(OH)D with serum DBP changes. | Samples are collected at pre-operative visit on the day of surgery, post-operative (on average 1 to 2 days after surgery) and 6 weeks post-operative visits | 
| Effects of hip arthroplasty on vitamin D metabolite levels in the blood. | We will evaluate the acute and chronic effects of hip arthroplasty on vitamin D metabolites, vitamin D pathway constituents, inflammation, oxidative stress and metabolic markers in plasma using mass spectrometric proteomic and metabolomics analysis. | Samples are collected at pre-operative visit on the day of surgery, post-operative (on average 1 to 2 days after surgery) and 6 weeks post-operative visits | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vitamin D, Vitamin D deficiency, Hip Arthroplasty