Foot-Related Health Care Use in Patients With
Rheumatoid Arthritis in an Outpatient Secondary
Care Center for Rheumatology and Rehabilitation
in The Netherlands: A Cohort Study With a
Maximum of Fifteen Years of Followup
ANNEKE F. MARSMAN,
1RUTGER DAHMEN,
1LEO D. ROORDA,
1DIRKJAN
VANSCHAARDENBURG,
2JOOST DEKKER,
2KARIN BRITSEMMER,
1DIRK L. KNOL,
3ANDMARIKE
VAN DERLEEDEN
2Objective. To describe foot-related health care use over time in a cohort of rheumatoid arthritis (RA) patients in an outpatient secondary care center for rheumatology and rehabilitation in The Netherlands.
Methods. A total of 1,087 patients with recent-onset RA from 1995 to September 2010 were included in the study. All foot-related visits to the podiatrist, rehabilitation physician, orthopedic surgeon, and the multidisciplinary foot-care clinic were registered and described. Logistic regression techniques for longitudinal data were used to analyze the course of foot-related health care use.
Results. A total of 32.9% of patients visited a podiatrist in secondary care during the course of their disease. For most patients, a visit to the podiatrist took place during the first year after diagnosis. This was followed by a significant decrease in visits in the ensuing years. Nine percent of patients visited the rehabilitation physician with foot symptoms, with peak prevalences between year 10 and 11 and during year 14 of followup. The orthopedic surgeon was visited by 5.3% of patients with foot symptoms, with a significant increase in visits over time. The multidisciplinary foot-care clinic was visited by 7.5% of patients. This was significantly associated with visits to the rehabilitation physician.
Conclusion. In an outpatient secondary care center in The Netherlands, RA patients with foot symptoms visited the podiatrist in an early stage of the disease. When foot symptoms worsened, patients visited the rehabilitation physician, who subsequently referred patients to the multidisciplinary foot-care clinic for therapeutic footwear. The orthopedic surgeon was the final step in the management of foot symptoms.
INTRODUCTION
Foot symptoms are a common feature of rheumatoid ar-thritis (RA). As many as 90% of RA patients experience foot symptoms at some point in the course of their disease (1). At disease onset, it is predominantly the metatarso-phalangeal (MTP) joints that develop synovitis, leading to
pain and swelling of the forefoot. In turn, synovitis of the MTP joints can have a destructive impact on the quality and structure of the joints and surrounding soft tissues (2,3). Pain, swelling, and structural alterations of the foot can cause walking disabilities (4,5) and a decrease in qual-ity of life (6,7). Data on the prevalence and course of forefoot impairments in the first 8 years following initial diagnosis of RA are available (2). These data show a rapid increase in the percentage of new patients presenting with erosions during the first 2 years after diagnosis, with a slight decline during the years that follow. The prevalence of pain and swelling of MTP joints is accordingly high in these first 2 postdiagnosis years, after which stabilization in the pain and swelling takes place. A relationship be-tween the prevalence of foot impairments and health care use due to these foot impairments during the course of the disease is expected.
The management of foot symptoms can be divided into pharmacologic and nonpharmacologic management.
Phar-1Anneke F. Marsman, BSc, Rutger Dahmen, MD, Leo D. Roorda, MD, PT, PhD, Karin Britsemmer, MD: Reade, Am-sterdam, The Netherlands; 2Dirkjan van Schaardenburg, MD, PhD, Joost Dekker, PhD, Marike van der Leeden, PT, PhD: Reade and VU University Medical Center, Amsterdam, The Netherlands;3
Dirk L. Knol, PhD: VU University Medi-cal Center, Amsterdam, The Netherlands.
Address correspondence to Marike van der Leeden, PT, PhD, Amsterdam Rehabilitation Research Center, Reade, PO Box 58271, 1040 HG Amsterdam, The Netherlands. E-mail: [email protected].
Submitted for publication March 16, 2012; accepted in revised form June 22, 2012.
DOI 10.1002/acr.21787
© 2013, American College of Rheumatology
ORIGINAL ARTICLE
macologic management is mainly systemic, consisting of nonsteroidal antiinflammatory drugs, corticosteroids, and disease-modifying antirheumatic drugs (DMARDs) and biologic treatments (8,9). Nonpharmacologic management is mainly locally administered, and can be either conser-vative or surgical in nature. Conserconser-vative management, consisting of foot orthoses in nonprescription shoes or therapeutic footwear, aims to decrease foot pain and dis-ability (9 –11). Specific foot problems may require surgical treatment, such as severe subluxation of the MTP joints or severe hallux valgus (12).
Until now, health care use in RA patients with foot symptoms has only been studied using a cross-sectional study design (5,12,13). Longitudinal data concerning the use of both conservative and surgical interventions are lacking. The knowledge of health care use due to foot symptoms may give relevant insight into the type and
Cohort (EAC) of Reade, an outpatient secondary care cen-ter for rheumatology and rehabilitation (14). This cohort was established in 1995 to study a wide variety of research topics, including the presence and course of the signs and symptoms of the disease process. The exclusion criteria for the EAC are having a history of treatment with DMARDs and the presence of ⱖ1 of the following comorbidities: crystal arthropathy, osteoarthritis, systemic lupus ery-thematosus, Sjo¨gren’s syndrome, infectious arthritis, and spondylarthropathy. As of September 2010, a total of 2,023 patients had been included and followed up in the EAC. The patients’ disease activity, joint damage (as scored by radiographs), and functional capacity were assessed at dif-ferent time points. The drug treatment decisions were made by the rheumatologists according to clinical practice standards.
Patient selection. In the present study, 1,087 patients (54% of the 2,023 patients included and followed up in the EAC) fulfilled the 1987 American College of Rheumatology criteria for RA (15) at baseline and/or 1 year after inclu-sion. For these patients, health care use related to foot symptoms was registered. As patients were included from 1995 until September 2010, the duration of followup be-tween the patients varied (Figure 1). Data were available
Figure 1. Schematic view of our research design. Values are the number of pa-tients fulfilling the American College of Rheumatology criteria enrolled in the Early Arthritis Cohort (EAC) each year since 1995. Rheumatoid arthritis (RA) patients registered in September 2010 were included in the present study (moment of inclusion).
management of foot symptoms.
● In view of the high prevalence of painful and swol-len metatarsophalangeal joints early in the RA dis-ease process, this study points out the possibility of underuse of care, which is an important target for future research.
for all patients at disease onset; however, subsequent data were only available for patients with a longer followup period. Patients who relocated (n⫽ 67) or died (n⫽ 57) were considered lost to followup.
Procedures. In a secondary care center in The Neth-erlands, rheumatologists can refer RA patients with foot symptoms to a variety of specialists, including podiatrists, rehabilitation physicians, and orthopedic surgeons (Fig-ure 2). The latter 2 specialists can refer patients to the podiatrist or to the multidisciplinary foot-care clinic. The multidisciplinary foot-care clinic is a collaboration be-tween a rehabilitation physician and an orthopedic shoe-maker. In the majority of cases, referrals result in one of the following interventions: the provision of foot orthoses in nonprescription shoes, therapeutic footwear, or ortho-pedic surgery (Figure 2).
Measures. Demographic and clinical characteristics.
Demographic data, general disease-related factors, and foot-related factors were recorded in the EAC. The demo-graphic data used in the present study were sex and age. The general disease-related factors at baseline included the Disease Activity Score in 28 joints (DAS28) (16), the percentage of patients who tested positive for IgM rheu-matoid factor, symptom duration, the total Sharp/van der Heijde score (SHS), and the total score of the Health As-sessment Questionnaire (HAQ) (17). The walking dis-ability subscale of the HAQ was reported separately. The foot-related factors at baseline included erosion and joint space narrowing of the MTP and interphalangeal joints (using the SHS) (18), pain by palpation of the MTP joints, and the presence or absence of swelling of the MTP joints.
Foot-related health care use. All visits to the podiatrist, rehabilitation physician, orthopedic surgeon, and the mul-tidisciplinary foot-care clinic were registered in the Reade registration system. Whether a visit to the rehabilitation physician or orthopedic surgeon was (partially) related to foot symptoms and the type of intervention prescribed during such a visit was independently registered by 3
researchers (AFM and RD or AFM and LDR) using the patient’s medical records and a standard case record form. Consensus regarding whether a visit concerned foot symp-toms and the intervention prescribed was high between the researchers. Consensus on these issues was immedi-ately reached in 85.1% and 81.5% of rehabilitation phy-sician consultations and orthopedic surgeon consulta-tions, respectively. In the remaining cases, consensus was reached after discussion.
Statistical analysis. For the demographic and clinical characteristics, means and SDs were calculated for age and DAS28 score, while medians and interquartile ranges (IQRs) were calculated for the remaining patient characteristics at baseline. Regarding the prevalence of painful and swollen MTP joints, forefoot joint damage, and walking disability, percentages were calculated using a cutoff score of ⱖ1 for all variables. Additionally, t -tests, Mann-Whitney -tests, and Pearson’s chi-square tests were performed to compare baseline characteristics of patients with full followup (n⫽ 963) against those who were lost to followup (n ⫽ 124). Two-sided testing was used, and P values less than 0.05 were considered sig-nificant.
For foot-related health care, secondary care health care use during the disease process was visualized in graphs per year of followup. To analyze the course of health care use, logistic regression analyses for longitudinal data were performed using generalized estimating equation analyses, corrected for the duration of followup. The patients were divided into 11 cohorts based on the year of inclusion. The eleventh cohort contained all patients included be-tween 2005 and 2010 because of the scarcity of data for each year in this period. We subsequently investigated whether the association between health care use and the disease process was linear, quadratic, or cubic. Pearson’s chi-square test was performed on health care use per dis-cipline, in order to ascertain any correlations between disciplines. A P value of less than 0.05 was considered significant. All analyses were performed using SPSS, ver-sion 17.0.
Figure 2. Flow chart showing the main routes of health care for patients with rheumatoid arthritis and foot symptoms in a secondary care center in The Neth-erlands.
RESULTS
Patient characteristics. The baseline characteristics of the patients are shown in Table 1. There were differences between the patients with full followup (n⫽963) and the patients lost to followup (n⫽124; data not shown). The group of patients lost to followup had a lower percentage of women (58.9% versus 72.0%; P ⫽ 0.003), was older (59.9 versus 53.7 years; P ⱕ 0.001), and had a higher DAS28 score (5.6 versus 5.1; P ⱕ 0.001) compared to patients with full followup.
Health care use. Podiatrist. A total of 357 patients (32.9%) visited the podiatrist in secondary care during the
course of their disease. The median time between diag-nosis and the initial visit to the podiatrist was 1.0 year (IQR 0.0 –2.0 years). A total of 13 patients were referred to the podiatrist by the rehabilitation physician and orthope-dic surgeon. The remaining patients were directly referred by their rheumatologist. The prevalence of visits to the podiatrist was highest in the first 2 years after diagnosis (Figure 3A). A significant linear decrease in visits to the podiatrist of 6.0% per year was shown by the logistic regression analyses (P ⫽ 0.002) (Figure 4A). The differ-ences between the cohorts were negligible.
Rehabilitation physician. A total of 323 patients (29.8%) visited the rehabilitation physician during the course of their disease, 97 (30.0%) of which had foot symptoms. The
SHS total score, median (IQR) 0 (0.0–2.0) 790† Erosion score feet (ⱖ1 joint), % 16.5 806† Erosion score feet, median (IQR) 0.0 (0.0–0.0) 806† Joint space narrowing feet (ⱖ1 joint), % 15.1 806† Joint space narrowing score feet, median (IQR) 0.0 (0.0–0.0) 806† SHS feet, median (IQR) 0.0 (0.0–0.0) 806† HAQ DI total score, median (IQR) 1.3 (0.6–1.9) 1,062 HAQ DI walking subscale (scoreⱖ1), % 46.5 1,061 HAQ DI walking subscale, median (IQR) 0.0 (0.0–1.0) 1,061 * IQR⫽interquartile range; DAS28⫽Disease Activity Score in 28 joints; MTP⫽metatarsophalangeal; SHS⫽Sharp/van der Heijde; HAQ⫽Health Assessment Questionnaire; DI⫽disability index. † Reduced numbers in the SHS are due to a delay in the scoring of radiographs.
Figure 3. Percentage and confidence interval of patients visiting the podiatrist (A), the rehabilitation physician (B), the orthopedic surgeon (C), and the multi-disciplinary foot-care clinic (D) during the course of the disease.
median time between diagnosis and the first foot-related visit was 3.0 years (IQR 1.0 – 6.0 years). Among these 97 patients, an increase in visits over time was observed, with a peak prevalence occurring between year 10 and 11 of the disease. This peak was followed by a subsequent decrease in visits, with a second peak occurring at 14 years of followup (n ⫽ 37) (Figure 3B). This line was confirmed using logistic regression analyses, which showed a signif-icant quadratic association between visits to the rehabili-tation physician and time (P ⫽ 0.045) (Figure 4B). The observed differences between the cohorts were negligible. The rehabilitation physician referred 95 patients (97.9% of the foot-related visits) for an intervention. Among these patients, 68 were referred to 1 specialist and 27 toⱖ2 specialists, resulting in a total of 129 referrals. Patients who were referred toⱖ2 specialists were mainly referred to the multidisciplinary foot-care clinic in combi-nation with diagnostic procedures. Eleven patients were referred to the podiatrist after a median time of 2.0 years (IQR 1.0 –3.0 years) following diagnosis and 5 patients received foot orthoses during the course of their disease. Four patients were referred to the orthopedic surgeon after a median time of 6.5 years (IQR 4.5– 8.5 years) following diagnosis. A total of 73 patients were referred to the mul-tidisciplinary foot-care clinic to be supplied with thera-peutic footwear after a median time of 3.0 years (1.0 – 6.0 years) following diagnosis. Four patients were referred for adjustments to their conventional shoes. A total of 32 patients were referred after a median time of 4.0 years (IQR 1.3–5.8 years) for other, mainly diagnostic procedures fol-lowing the initial diagnosis.
Orthopedic surgeon. A total of 150 patients (13.8%) vis-ited the orthopedic surgeon in the course of their disease, of which 57 (38.0%) had foot symptoms. The median time between diagnosis and the first foot-related visit was 3
years (IQR 1.0 –7.0 years). Among these 57 patients, a minority of patients visited the orthopedic surgeon during the first year of their disease (Figure 3C). Logistic regres-sion analyses showed a significant increase in visits of 9.0% per year (P⫽0.010) (Figure 4C). The observed dif-ferences between the cohorts were negligible.
The orthopedic surgeon referred 56 patients (98.2% of the foot-related visits) for an intervention. Among these patients, 30 were referred to 1 specialist and 26 to ⱖ2 specialists, resulting in a total of 100 referrals. Patients who were referred toⱖ2 specialists were mainly referred to the orthopedic surgeon in combination with diagnostic procedures. Two patients were referred to the podiatrist after a median time of 5.0 years (IQR 2.0 – 8.0 years) fol-lowing diagnosis and 9 patients received foot orthoses. Thirty-two patients underwent orthopedic surgery after a median time of 4.0 years (IQR 2.0 –7.8 years) following the initial diagnosis. A total of 13 patients were referred to the multidisciplinary foot-care clinic after a median time of 4.0 years (IQR 2.0 – 8.0 years) following diagnosis, and in a majority of the cases, this was to supply the patients with therapeutic footwear. Five patients were referred for ad-justments to their conventional shoes. A total of 39 pa-tients were referred for other, mainly diagnostic proce-dures after a median time of 3.0 years (IQR 2.0 –7.0 years) following diagnosis.
Multidisciplinary foot-care clinic. A total of 86 patients were referred by the rehabilitation physician and the or-thopedic surgeon to the multidisciplinary foot-care clinic to be supplied with therapeutic footwear. Ultimately, a total of 81 patients (7.5%) visited the multidisciplinary foot-care clinic. The median time between diagnosis and the first visit to the multidisciplinary foot-care clinic was 3.0 years (IQR 1.0 –5.5 years). During the first 3 years after diagnosis, a minority of patients visited the
multidisci-Figure 4. Model-based proportion of patients visiting the podiatrist (A), the reha-bilitation physician (B), the orthopedic surgeon (C), and the multidisciplinary foot-care clinic (D) during the course of the disease.
DISCUSSION
This study investigated specialist-provided foot-related health care usage in patients with RA, with a maximum of 15 years of followup. The present study took place in a secondary care center, with health care professionals within one center focusing on foot symptoms, which made it more likely for patients to be referred to other foot-related specialists. The prevalence of visits reported in this study might therefore be an overestimation when compared to visits of patients not treated in a secondary care institution specializing in rheumatology and rehabil-itation.
The patients with foot symptoms were most likely to be seen by the podiatrist, who was visited by 32.9% of pa-tients during the course of their disease. In particular, patients with foot symptoms developing early in the dis-ease process were referred to the podiatrist by the rheu-matologist. This is evident, given that 15% of patients visited the podiatrist in the first year after diagnosis. This can be explained by the easily accessible and noninvasive nature of podiatry, mainly consisting of foot and/or toe orthoses and additional shoe-related advice. The results of another recent study from our research group showed that podiatric treatment in the early phase of the disease resulted in better outcomes regarding pain and disability than podiatric treatment later in the disease process, when irreversible joint damage and deformities could have developed (19).
In the present study, a minority of patients visited the rehabilitation physician, the orthopedic surgeon, and the multidisciplinary foot-care clinic during the first 2 years following diagnosis, with an increase in the years that followed. When podiatry was not sufficient because of worsening of the foot symptoms (e.g., due to erosions and structural deformities), the rheumatologist subse-quently referred patients to the rehabilitation physician after a median time of 3 years. The rheumatologist and the rehabilitation physician have different roles in The Neth-erlands; the rheumatologist is primarily responsible for the pharmacologic management, while the rehabilitation physician is responsible for the nonpharmacologic con-servative management. In general, concon-servative manage-ment consists of multidisciplinary treatmanage-ment. In the pres-ent study, the rehabilitation physician made the most of his or her referrals to the multidisciplinary foot-care clinic,
of patients (n ⫽ 1,087) and long followup duration (15 years) of this study made it possible to review foot-related health care use during the course of RA. Due to the absence of comparable studies, it is impossible to discuss the re-sults found in this study in reference to other studies.
The limitations of this study mainly concern the type of prescribed interventions. The present data show whether a patient received podiatric treatment or surgery, but infor-mation regarding the specific type of orthoses supplied to patients or the exact surgical procedures undertaken is lacking. Furthermore, antirheumatic drugs influence the disease course and might subsequently influence the de-velopment and severity of foot symptoms and, therefore, the use of foot-related health care. Treatment strategies have evolved throughout time and great innovations have been made by the emergence of anti–tumor necrosis factor
␣therapies. Since information about the use of medication is not consistently registered in the EAC, the influence of these new therapies on foot-related health care use is not known. Finally, in the Dutch health care system, patients can also be referred directly to a primary care podiatrist by their primary care physician. Moreover, some patients pre-ferred to receive podiatry by a primary care podiatrist outside the center. These routes were not included in the present study, which took place in a secondary care center. So, although the majority of patients would be expected to have received foot-related care in our outpatient clinic, the reported percentages concerning podiatry might be an un-derestimation. Also, basic podiatric care, such as callus debridement and nail cutting, was not included in this study.
In view of the high prevalence of painful and swollen MTP joints early in the RA disease process (⬃70% of patients have painful or swollen MTP joints at diagnosis) (2), the question arises as to whether there is an underuse of care for foot symptoms, most likely being reported as pain during weight-bearing activities, such as standing, walking, and running. Woodburn et al describe a window of opportunity in the early phases of RA, consisting of the early detection of foot problems, targeted therapy, tight control of foot arthritis, and disease monitoring (20). It might be assumed that early podiatry intervention pre-vents further pain, loss of foot function, and loss of phys-ical functioning, although there is limited evidence to support this assumption (21). The present study points out the possibility of an underuse of care, which is an impor-tant target for future research. Further development of preventive health care strategies and integrated foot care
(e.g., standard referral of newly diagnosed RA patients to the podiatrist) are possible strategies for the prevention of the underuse of care (20).
In conclusion, RA patients with foot symptoms visited the podiatrist at an early stage in the disease process. When foot symptoms worsened, patients visited the reha-bilitation physician, who subsequently referred patients to the multidisciplinary care clinic for therapeutic foot-wear. The orthopedic surgeon was the final step in the management of foot symptoms.
AUTHOR CONTRIBUTIONS
All authors were involved in drafting the article or revising it critically for important intellectual content, and all authors ap-proved the final version to be published. Dr. van der Leeden had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study conception and design. Marsman, Dahmen, Roorda, van der Leeden.
Acquisition of data.Marsman, Dahmen, Roorda, van Schaardenburg, Britsemmer, van der Leeden.
Analysis and interpretation of data.Marsman, Dahmen, Roorda, Dekker, Knol, van der Leeden.
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