The main study population that forms the focus of this thesis is a cohort of consecutively, prospectively recruited patients with rheumatoid arthritis (RA) who have contributed to the ‘FeeTURA’ programme of work from 2007–2011. Two additional participant groups, including those with medial knee osteoarthritis (OA) or healthy volunteers (HV) were also included in a comparative study, reported in chapter five.
3.4.1 Target populations & recruitment strategy
Experimental study one: This study is a longitudinal evaluation of patients with RA who have
contributed to the ‘FeeTURA’ research project over three-years, for whom baseline and one- year follow-up data has been previously reported (Bowen et al. 2010c, Bowen et al. 2009). At baseline, patients with a consultant confirmed diagnosis of RA, (according to 1987 ACR criteria (Arnett et al. 1988)), attending a Southampton based outpatient rheumatology clinic, were prospectively, consecutively recruited to the study between July 2006 and January 2007. Patients were given information about the study at the time of their clinical appointment and
invited to contact the research team for further information or to declare their interest in participation. Participants who completed the baseline appointment were invited to return for subsequent year-one follow-up by way of letter of invitation. Participants who attended both baseline and year-one appointments were considered eligible for entry into the year-three follow-up study and again contacted by way of a letter of invitation and reply slip (see appendix section A6).
Experimental study two: This study is a comparative evaluation of patients with RA, medial
knee osteoarthritis (OA) or healthy volunteers (HV). Those patients with RA who contributed to experimental study one, were also included within this study. Patients with a consultant confirmed diagnosis of medial compartment knee OA of Kellgren and Lawrence grade≥2, in at least one knee, were recruited from a known cohort who had previously participated in a trial of vitamin D supplementation (the ‘VIDEO’ study). Participants were originally consecutively, prospectively recruited to the VIDEO study from a population of patients attending a general rheumatology outpatient clinic in Southampton between December 2005 and April 2009. Participants from the VIDEO study were consecutively, retrospectively identified from those completing the final episode of data collection within the trial and invited to participate within this study by way of letter of invitation. Recruitment of patients with OA to this study was completed in phases, from December 2009 to December 2010, until the target sample size was achieved. Healthy volunteers were recruited from staff and students attending the University of
Southampton between July 2011 and November 2011. Potential participants were informed of the study by way of poster displays which contained researcher contact information. Following receipt of an expression of interest the researcher contacted the potential participants to complete eligibility checks and arrange an appointment.
Experimental studies three and four: Those patients with RA who contributed to experimental
study one, were eligible for screening to studies three and four. Eligible participants were invited to complete this study by way of letter of invitation and reply slip, and accompanying patient information sheet (see appendix sections A5 and A6). Upon receipt of the reply slip, participants were contacted by the researcher to complete final screening checks and to arrange an
appointment.
3.4.2 Inclusion and exclusion criteria
The inclusion and exclusion criteria for the patient groups contributing to this thesis were defined as follows:
Inclusion criteria
For RA participants, patients were included who:
had a diagnosis of RA according to the ACR criteria
were attending a SUHT rheumatology outpatients’ clinic between Jul 2006 and Jan 2007 took part in the baseline FeeTURA study
were aged between 18-80 years at the time of initial recruitment into the previous baseline FeeTURA study
For OA participants, patients were included in who:
had radiological evidence of early OA disease at medial tibio-femoral knee compartment (based upon a modified Kellgren and Lawrence score of 2-3 (Lawrence et al. 1966), and Joint space width of >1mm)
were able and willing to attend or comply with treatment and follow-up had pain in the knee for most days of the previous month
were ambulatory at the time of recruitment into the VIDEO study
were aged 50 years or over at the time of initial recruitment into the VIDEO study had taken part in the baseline VIDEO study
For HV, individuals were included who:
have no diagnosis of a musculoskeletal condition
are a student or staff member at Southampton University
are willing to participant in the study, providing full informed consent
Exclusion criteria
For RA participants, patients were excluded who:
had received corticosteroid injection therapy to the forefoot within the 12 weeks prior to the commencement of the initial FeeTURA study
were unable to walk a distance of 5metres
had concomitant musculoskeletal disease (e.g. primary osteoarthritis, gout, Paget’s disease, systemic lupus erythematous)
had a serious medical or psychological disorder that would prevent compliance with the study protocol
were unable to provide informed consent
Additional exclusion criteria applicable to patients with RA otherwise eligible to complete MRI included:
have a pacemaker fitted
have other electronically, magnetically or mechanically activated medical device or implant that may be adversely affected by the MRI procedure
have a history of eye injury involving metal fragments have a cochlear implant
have renal dysfunction were pregnant
have a history of forefoot surgery with metallic fixation devices still in situ
For OA participants, patients were excluded who:
had secondary OA subsequent to any of the following: septic arthritis, gout, pseudo-gout, Wilson’s disease, Paget’s disease, hyperparathyroidism, hypothyroidism, sarcoidosis, osteomalacia, osteoporotic fracture, a history of inflammatory disease, hypercalcaemia or hypercalciuria
were using any of the following at the time of initial recruitment into the VIDEO study: glucosamine or chondroitin within the 12 weeks prior to recruitment, bisphosphonates, vitamin D supplementation with at total vitamin D content>200iµ, any anti-epileptic medication
had received any intra-articular corticosteroid injection therapy within the 12 weeks prior to recruitment into the VIDEO study
had received injection of Hyalgan within the 24 weeks prior to recruitment into the VIDEO study
had undergone any surgical procedure to the knee in the 24 weeks prior to recruitment into the VIDEO study
were pregnant at the time of recruitment into the VIDEO study
For HV, individuals were excluded who:
Have had corticosteroid injection therapies to the forefoot within the previous 3 months prior to commencement of the study
Have a musculoskeletal/rheumatological disease (e.g. primary osteoarthritis, rheumatoid arthritis, gout, Paget’s disease, systemic lupus erythematous)
Have a serious medical or psychological disorder that would affect the study protocol Are unable to comply, understand or are unwilling to participate in the requirements of this
investigation
Are unable to give informed consent
3.4.2 Withdrawal of participants
Participants were able to withdraw from the study at any time without providing a reason for doing so. At the time of consent all participants were reminded that they were able to withdraw at any point and that, if applicable, this would have no adverse consequence to their ongoing clinical care.
In the event of a participant with RA wishing to withdraw from the study they would not be replaced because all possible participants from the original FeeTURA study will already have been invited to participate. In the event of a participant with OA wishing to withdraw from the study, it was possible to fill this opportunity to participate via further consecutive, retrospective
recruitment from the VIDEO study population. In the event of a healthy volunteer wishing to withdraw from the study, they could be replaced by continued recruitment.