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Patients With Higher Treatment Outcome Expectations Are More Satisfied With the Results of Nonoperative Treatment for Thumb Base Osteoarthritis: A Cohort Study

Open AccessPublished:February 10, 2021DOI:https://doi.org/10.1016/j.apmr.2021.01.080

      Highlights

      • Satisfaction after nonoperative treatment for osteoarthritis of the first carpometacarpal joint is not yet optimal.
      • Positive expectations of treatment outcomes are associated with higher satisfaction.
      • Optimizing expectations might improve treatment outcomes and satisfaction.

      Abstract

      Objective

      To investigate how satisfaction with treatment outcome is associated with patient mindset and Michigan Hand Outcome Questionnaire (MHQ) scores at baseline and 3 months in patients receiving nonoperative treatment for first carpometacarpal joint (CMC-1) osteoarthritis (OA).

      Design

      Cohort study

      Setting

      A total of 20 outpatient locations of a clinic for hand surgery and hand therapy in the Netherlands.

      Participants

      Patients (N=308) receiving nonoperative treatment for CMC-1 OA, including exercise therapy, an orthosis, or both, between September 2017 and February 2019.

      Interventions

      Nonoperative treatment (ie, exercise therapy, an orthosis, or both)

      Main Outcome Measures

      Satisfaction with treatment outcomes was measured after 3 months of treatment. We measured total MHQ score at baseline and at 3 months. As baseline mindset factors, patients completed questionnaires on treatment outcome expectations, illness perceptions, pain catastrophizing, and psychological distress. We used multivariable logistic regression analysis and mediation analysis to identify factors associated with satisfaction with treatment outcomes.

      Results

      More positive pretreatment outcome expectations were associated with a higher probability of being satisfied with treatment outcomes at 3 months (odds ratio, 1.15; 95% confidence interval, 1.07-1.25). Only a relatively small part (33%) of this association was because of a higher total MHQ score at 3 months. None of the other mindset and hand function variables at baseline were associated with satisfaction with treatment outcomes.

      Conclusions

      This study demonstrates that patients with higher pretreatment outcome expectations are more likely to be satisfied with treatment outcomes after 3 months of nonoperative treatment for CMC-1 OA. This association could only partially be explained by a better functional outcome at 3 months for patients who were satisfied. Health care providers treating patients nonoperatively for CMC-1 OA should be aware of the importance of expectations and may take this into account in pretreatment counseling.

      Keywords

      List of abbreviations:

      CEQ (Credibility and Expectancy Questionnaire), CMC-1 (first carpometacarpal joint), MHQ (Michigan Hand Outcome Questionnaire), OA (osteoarthritis), OR (odds ratio)
      Osteoarthritis (OA) of the first carpometacarpal joint (CMC-1) is a common disease, especially in postmenopausal women.
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      Exercise therapy in addition to an orthosis reduces pain more than an orthosis alone in patients with thumb base osteoarthritis: a propensity score matching study.
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      Surgery can be considered if symptoms are not sufficiently relieved by nonoperative treatment.
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      Richtlijn Conservatieve en Chirurgische Behandeling van Primaire Artrose van de Duimbasis: Nederlandse Vereniging voor Plastische Chirurgie (NVPC) [Dutch] [Guideline for non-surgical and surgical treatment of primary osteoarthritis of the thumb base: Dutch society for Plastic Surgery].
      Nonoperative treatment is a successful treatment strategy for CMC-1 OA, which, on average, reduces pain and improves hand function.
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      • Kloppenburg M.
      Efficacy and safety of non-pharmacological, pharmacological and surgical treatment for hand osteoarthritis: a systematic literature review informing the 2018 update of the EULAR recommendations for the management of hand osteoarthritis.
      Moreover, in a large cohort with a mean follow-up of 2.2 years, only 15% of the patients underwent further surgery.
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      Outcome of a hand orthosis and hand therapy for carpometacarpal osteoarthritis in daily practice: a prospective cohort study.
      Treatment outcomes such as pain relief and functional improvement have been frequently studied; however, in recent days there is increasing attention for the patients’ interpretation of their treatment outcomes.
      • Graham B.
      Defining and measuring patient satisfaction.
      Previous studies demonstrated that after hand therapy and an orthosis for CMC-1 OA, there is considerable variation in patients’ satisfaction with treatment outcomes. However, which factors explain this variation in satisfaction with treatment outcomes for these patients is still unknown.
      • Wouters R.M.
      • Tsehaie J.
      • Slijper H.P.
      • et al.
      Exercise therapy in addition to an orthosis reduces pain more than an orthosis alone in patients with thumb base osteoarthritis: a propensity score matching study.
      ,
      • Tsehaie J.
      • Spekreijse K.R.
      • Wouters R.M.
      • et al.
      Outcome of a hand orthosis and hand therapy for carpometacarpal osteoarthritis in daily practice: a prospective cohort study.
      It has previously been reported that pain and hand function after treatment are associated with satisfaction with treatment outcomes for patients with hand and wrist disorders receiving surgical treatment or steroid injections.
      • Marks M.
      • Audige L.
      • Reissner L.
      • Herren D.B.
      • Schindele S.
      • Vliet Vlieland T.P.
      Determinants of patient satisfaction after surgery or corticosteroid injection for trapeziometacarpal osteoarthritis: results of a prospective cohort study.
      ,
      • Marks M.
      • Herren D.B.
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      • Simmen B.R.
      • Angst F.
      • Goldhahn J.
      Determinants of patient satisfaction after orthopedic interventions to the hand: a review of the literature.
      Additionally, patient mindset has been shown to be associated with satisfaction with treatment outcomes, again after either surgical treatment or steroid injections.
      • Marks M.
      • Herren D.B.
      • Vliet Vlieland T.P.
      • Simmen B.R.
      • Angst F.
      • Goldhahn J.
      Determinants of patient satisfaction after orthopedic interventions to the hand: a review of the literature.
      ,
      • Kadzielski J.
      • Malhotra L.R.
      • Zurakowski D.
      • Lee S.G.
      • Jupiter J.B.
      • Ring D.
      Evaluation of preoperative expectations and patient satisfaction after carpal tunnel release.
      Patient mindset can be seen as particular associations and expectations that a patient has, which could affect a patients’ attitude toward treatment.
      • Crum A.J.
      • Leibowitz K.A.
      • Verghese A.
      Making mindset matter.
      Because patients generally have a particular mindset toward a treatment before starting treatment, communication between a clinician and patients could be an opportunity to modify this mindset, for example, by changing expectations.
      • Crum A.
      • Zuckerman B.
      Changing mindsets to enhance treatment effectiveness.
      There have already been studies on the association between expectations and satisfaction in daily practice, but there is no consensus. Several authors suggested that patients with high expectations would be less satisfied because these patients are less likely to have their expectations fulfilled.
      • Marks M.
      • Audige L.
      • Reissner L.
      • Herren D.B.
      • Schindele S.
      • Vliet Vlieland T.P.
      Determinants of patient satisfaction after surgery or corticosteroid injection for trapeziometacarpal osteoarthritis: results of a prospective cohort study.
      ,
      • Kadzielski J.
      • Malhotra L.R.
      • Zurakowski D.
      • Lee S.G.
      • Jupiter J.B.
      • Ring D.
      Evaluation of preoperative expectations and patient satisfaction after carpal tunnel release.
      ,
      • Frouzakis R.
      • Herren D.B.
      • Marks M.
      Evaluation of expectations and expectation fulfillment in patients treated for trapeziometacarpal osteoarthritis.
      Many surgeons apply this principle in practice.
      • Waljee J.F.
      • Chung K.C.
      Commentary regarding “Evaluation of expectations and expectation fulfillment in patients treated for trapeziometacarpal osteoarthritis”.
      However, other studies have suggested that patients should have positive expectations to improve treatment outcomes.
      • Brown W.A.
      Expectation, the placebo effect and the response to treatment.
      • Di Blasi Z.
      • Harkness E.
      • Ernst E.
      • Georgiou A.
      • Kleijnen J.
      Influence of context effects on health outcomes: a systematic review.
      • Testa M.
      • Rossettini G.
      Enhance placebo, avoid nocebo: how contextual factors affect physiotherapy outcomes.
      • Cormier S.
      • Lavigne G.L.
      • Choiniere M.
      • Rainville P.
      Expectations predict chronic pain treatment outcomes.
      • Hayden J.A.
      • Wilson M.N.
      • Riley R.D.
      • Iles R.
      • Pincus T.
      • Ogilvie R.
      Individual recovery expectations and prognosis of outcomes in non-specific low back pain: prognostic factor review.
      Possibly, this suggests that there is an optimum for expectations. Because of the conflicting suggestions in the literature, there is currently no consensus or best practice on how clinicians should deal with patients’ expectations to optimize treatment outcomes and satisfaction.
      While it has been reported that pain, hand function, and patient mindset are associated with satisfaction with treatment outcomes for patients receiving surgical treatment or steroid injections for hand and wrist conditions, it remains unknown if these factors also explain satisfaction with treatment outcomes in patients receiving nonoperative treatment for CMC-1 OA. In particular, the role of expectations is unclear. Therefore, the purpose of this study was to investigate which baseline characteristics, including total Michigan Hand Outcome Questionnaire (MHQ) score and patient mindset, are associated with the likelihood of being satisfied with treatment outcomes after 3 months of nonoperative treatment for CMC-1 OA when accounting for total MHQ score at 3 months.

      Methods

      Setting and study population

      Between September 2017 and February 2019, this cohort study was performed with routine outcome measurement data from Xpert Clinic and Handtherapie Nederland, comprising 20 outpatient locations for hand surgery and hand therapy in the Netherlands. Over 150 hand therapists and 23 European Board certified (Federation of European Societies for Surgery of the Hand) hand surgeons are employed in our clinic. The cohort and data collection procedures have previously been described in more detail.
      • Selles R.W.
      • Wouters R.M.
      • Poelstra R.
      • et al.
      Routine health outcome measurement: development, design, and implementation of the Hand and Wrist Cohort.
      All patients provided written informed consent, and this study was approved by the Erasmus MC Medical Ethical Committee.
      Patients were included when treated nonoperatively for CMC-1 OA after being diagnosed as having CMC-1 OA by a Federation of European Societies for Surgery of the Hand–certified hand surgeon. The diagnosis was made based on clinical presentation and radiographs when required. Nonoperative treatment consisted of immobilizing the CMC-1 using an orthosis and performing exercises to improve the active stability of the CMC-1 and strength of the thenar muscles. This treatment protocol has previously been described in more detail.
      • Wouters R.M.
      • Tsehaie J.
      • Slijper H.P.
      • et al.
      Exercise therapy in addition to an orthosis reduces pain more than an orthosis alone in patients with thumb base osteoarthritis: a propensity score matching study.
      Nonoperative treatment was offered for at least 3 months before surgery was considered. All hand therapists received the same training on how to treat patients with CMC-1 OA. However, treatment was not fully standardized as in randomized controlled trials, and therapists could deviate from this protocol based on patient preferences and clinical considerations.
      We invited all patients to complete the questionnaires as part of routine clinical care before and after treatment. The questionnaires were sent after the first consultation with the hand surgeon. In addition, baseline characteristics including age, sex, occupational intensity, duration of symptoms, hand dominance, and affected hand were collected. Occupational intensity was categorized as not employed, light occupational intensity (eg, working in an office), moderate occupational intensity (eg, working in a shop), or severe occupational intensity (eg, construction work). Patients who did not complete all questionnaires of interest at baseline and 3 months were excluded from the study.

      Outcome measurements

      Satisfaction with treatment outcomes was the primary outcome measure. This was measured using a self-designed questionnaire administered 3 months after the start of nonoperative treatment. In this questionnaire, we asked patients, “To what extent are you satisfied with the treatment outcomes obtained so far?” (rated as poor, moderate, fair, good, or excellent). We have dichotomized this, classifying patients rating their satisfaction with treatment outcomes as poor, moderate, or fair as less satisfied, while classifying patients rating their satisfaction as good or excellent as satisfied. We dichotomized satisfaction because the number of patients in some groups was not enough for analysis and, from a clinical point of view, because we aimed to identify factors that predicted whether patients would be satisfied or dissatisfied with treatment outcomes.
      At baseline and 3 months, we invited patients to complete the MHQ.
      • Chung K.C.
      • Pillsbury M.S.
      • Walters M.R.
      • Hayward R.A.
      Reliability and validity testing of the Michigan Hand Outcomes Questionnaire.
      The MHQ is a patient-reported outcome measure with good reliability, validity, and responsiveness for patients with CMC-1 OA.
      • Marks M.
      • Audige L.
      • Herren D.B.
      • Schindele S.
      • Nelissen R.G.
      • Vliet Vlieland T.P.
      Measurement properties of the German Michigan Hand Outcomes Questionnaire in patients with trapeziometacarpal osteoarthritis.
      The MHQ consists of 6 domains (pain, hand function, aesthetics, work, activities of daily life, satisfaction with hand function), each with a score ranging from 0-100 (0=poorest function, 100=ideal function). From these subscales, a total MHQ score is calculated for the affected hand, which is used in our analysis. We chose to use the total MHQ score at 3 months as functional improvement measure because it comprises a broad spectrum of domains relevant to patients with CMC-1 OA.
      We used the Credibility and Expectancy Questionnaire (CEQ)
      • Devilly G.J.
      • Borkovec T.D.
      Psychometric properties of the credibility/expectancy questionnaire.
      to measure outcome expectations regarding the treatment and the credibility of the treatment. This questionnaire has 2 domains (expectations and credibility) with 3 questions each. Scores per domain range from 3-27 (higher scores indicate higher expectations/credibility of the treatment).
      In addition, we measured pain catastrophizing behavior, psychological distress, and illness perceptions. We measured this using the Pain Catastrophizing Scale,
      • Sullivan M.J.L.
      • Bishop S.R.
      • Pivik J.
      The Pain Catastrophizing Scale: development and validation.
      the Patient Health Questionnaire-4,
      • Kroenke K.
      • Spitzer R.L.
      • Williams J.B.
      • Lowe B.
      An ultra-brief screening scale for anxiety and depression: the PHQ-4.
      and the Brief Illness Perception Questionnaire,
      • Broadbent E.
      • Petrie K.J.
      • Main J.
      • Weinman J.
      The brief illness perception questionnaire.
      respectively. We calculated a total score for each questionnaire. All questionnaires have been validated, and good reliability has been reported.
      • Devilly G.J.
      • Borkovec T.D.
      Psychometric properties of the credibility/expectancy questionnaire.
      ,
      • de Raaij E.J.
      • Schroder C.
      • Maissan F.J.
      • Pool J.J.
      • Wittink H.
      Cross-cultural adaptation and measurement properties of the Brief Illness Perception Questionnaire-Dutch Language Version.
      • Hallegraeff J.M.
      • van der Schans C.P.
      • Krijnen W.P.
      • de Greef M.H.
      Measurement of acute nonspecific low back pain perception in primary care physical therapy: reliability and validity of the Brief Illness Perception Questionnaire.
      • Lowe B.
      • Wahl I.
      • Rose M.
      • et al.
      A 4-item measure of depression and anxiety: validation and standardization of the Patient Health Questionnaire-4 (PHQ-4) in the general population.
      • Mertens V.C.
      • Moser A.
      • Verbunt J.
      • Smeets R.
      • Goossens M.
      Content validity of the Credibility and Expectancy Questionnaire in a pain rehabilitation setting.
      • Osman A.
      • Barrios F.X.
      • Gutierrez P.M.
      • Kopper B.A.
      • Merrifield T.
      • Grittmann L.
      The Pain Catastrophizing Scale: further psychometric evaluation with adult samples.
      • Osman A.
      • Barrios F.X.
      • Kopper B.A.
      • Hauptmann W.
      • Jones J.
      • O'Neill E.
      Factor structure, reliability, and validity of the Pain Catastrophizing Scale.

      Statistical methods

      We compared baseline characteristics for patients that were satisfied and less satisfied with treatment outcomes using t tests for normally distributed continuous data and Mann-Whitney-Wilcoxon tests for continuous data that were not normally distributed. Chi-square statistics were used for categorical data. Effect sizes (Cohen’s d) were calculated for any statistically significant differences between continuous data. We performed a nonresponder analysis to compare baseline characteristics of patients completing all questionnaires of interest (responders) and patients who only completed the MHQ at baseline and 3 months.
      After dichotomizing satisfaction with treatment outcomes, we used multivariable logistic regression analysis to determine which baseline variables were associated with the probability of being satisfied with treatment outcomes when adjusting for patient characteristics, patient-reported hand function at baseline, and patient mindset. For the logistic regression model, odds ratios (ORs) with 95% confidence intervals were calculated.
      In the multivariable regression model, we included the aforementioned baseline characteristics, patient-reported hand function (total MHQ score), psychological factors (total Pain Catastrophizing Scale score, total Patient Health Questionnaire-4, and total B-IPQ score), CEQ Expectancy Score, and CEQ Credibility Score. Using the rule of thumb of 1 variable per 10 cases having the lowest frequency outcome (number of events) to fit a multivariable logistic regression model and with 13 variables of interest, we needed to include at least 130 patients with an event. Assuming 50% of all patients would be classified as satisfied,
      • Wouters R.M.
      • Tsehaie J.
      • Slijper H.P.
      • et al.
      Exercise therapy in addition to an orthosis reduces pain more than an orthosis alone in patients with thumb base osteoarthritis: a propensity score matching study.
      we determined a minimum of 260 patients was needed. Because the number of patients treated in our clinic during the study period exceeded 260, we included all patients treated in our clinic during the study period.
      Because both patients with overly high and very low expectations have been suggested to be less satisfied, we hypothesized that there might be an optimum for CEQ Expectancy Score.
      • Marks M.
      • Herren D.B.
      • Vliet Vlieland T.P.
      • Simmen B.R.
      • Angst F.
      • Goldhahn J.
      Determinants of patient satisfaction after orthopedic interventions to the hand: a review of the literature.
      ,
      • Kadzielski J.
      • Malhotra L.R.
      • Zurakowski D.
      • Lee S.G.
      • Jupiter J.B.
      • Ring D.
      Evaluation of preoperative expectations and patient satisfaction after carpal tunnel release.
      ,
      • Frouzakis R.
      • Herren D.B.
      • Marks M.
      Evaluation of expectations and expectation fulfillment in patients treated for trapeziometacarpal osteoarthritis.
      ,
      • Brown W.A.
      Expectation, the placebo effect and the response to treatment.
      • Di Blasi Z.
      • Harkness E.
      • Ernst E.
      • Georgiou A.
      • Kleijnen J.
      Influence of context effects on health outcomes: a systematic review.
      • Testa M.
      • Rossettini G.
      Enhance placebo, avoid nocebo: how contextual factors affect physiotherapy outcomes.
      • Cormier S.
      • Lavigne G.L.
      • Choiniere M.
      • Rainville P.
      Expectations predict chronic pain treatment outcomes.
      • Hayden J.A.
      • Wilson M.N.
      • Riley R.D.
      • Iles R.
      • Pincus T.
      • Ogilvie R.
      Individual recovery expectations and prognosis of outcomes in non-specific low back pain: prognostic factor review.
      We therefore tested whether our multivariable regression model would better fit the data when a nonlinear effect of the CEQ Expectancy Score was included, using splines. We performed a likelihood ratio test to determine whether this model had a better fit than the model with CEQ Expectancy Score as a linear term.
      We checked for multicollinearity in our multivariable logistic regression model using the variance inflation factor. We considered a variance inflation factor >10 an indication for multicollinearity.
      • Kutner M.H.
      • Nachtsheim C.J.
      • Neter J.
      • Li W.
      Applied linear statistical models.
      As a secondary analysis (in addition to our multivariable logistic regression), we performed a mediation analysis.
      • Baron R.M.
      • Kenny D.A.
      The moderator-mediator variable distinction in social psychological research: conceptual, strategic, and statistical considerations.
      ,
      • Zhao X.S.
      • Lynch J.G.
      • Chen Q.M.
      Reconsidering Baron and Kenny: myths and truths about mediation analysis.
      Because previous studies in hand surgery and orthopedics reported an association between treatment outcomes and satisfaction, the aim of the mediation analysis was to quantify how much of the association between a predictor and the dependent variable of interest (in this case, satisfaction with treatment outcomes) is the result of treatment outcomes (indirect effect) and how much is independent of that (direct effect).
      • Marks M.
      • Herren D.B.
      • Vliet Vlieland T.P.
      • Simmen B.R.
      • Angst F.
      • Goldhahn J.
      Determinants of patient satisfaction after orthopedic interventions to the hand: a review of the literature.
      ,
      • Kahlenberg C.A.
      • Nwachukwu B.U.
      • McLawhorn A.S.
      • Cross M.B.
      • Cornell C.N.
      • Padgett D.E.
      Patient satisfaction after total knee replacement: a systematic review.
      For this mediation model, our predictor and mediator variables were continuous, and our outcome was binary.
      • Imai K.
      • Keele L.
      • Tingley D.
      A general approach to causal mediation analysis.
      • JJM Rijnhart
      • Twisk J.W.R.
      • Eekhout I.
      • Heymans M.W.
      Comparison of logistic-regression based methods for simple mediation analysis with a dichotomous outcome variable.
      • Vanderweele T.J.
      Explanation in causal inference: methods for mediation and interaction.
      • Vanderweele T.J.
      • Vansteelandt S.
      Odds ratios for mediation analysis for a dichotomous outcome.
      For the mediation model, we used the linear terms of all variables.
      We assessed whether mediation was present by bootstrapping the indirect effect, as proposed by Preacher and Hayes.
      • Preacher K.J.
      • Hayes A.F.
      SPSS and SAS procedures for estimating indirect effects in simple mediation models.
      We corrected for total MHQ score at intake in the analysis. The outcome of the mediation analysis is the proportion mediated, which is the percentage of the effect of the significant independent variable(s) due to the total MHQ score at 3 months. This is calculated by multiplying the regression coefficient of the predictor on the mediator with the regression coefficient of the mediator on the outcome.
      Mediation analysis was performed in Mplus version 8.1a, using Mplus code based on Feingold et al
      • Feingold A.
      • MacKinnon D.P.
      • Capaldi D.M.
      Mediation analysis with binary outcomes: direct and indirect effects of pro-alcohol influences on alcohol use disorders.
      for mediation with a continuous predictor and a nonrare binary outcome. All other analyses were performed using R statistical computing version 3.5.2.b For all tests, a P value <.05 was considered statistically significant.

      Results

      In the study period, 656 patients were treated nonoperatively for CMC-1 OA at our clinic and completed all relevant questionnaires at baseline. Of those patients, 308 patients also completed all questionnaires of interest 3 months after the start of treatment and were included in the analysis (fig 1).
      Figure thumbnail gr1
      Fig 1Flow chart of patient inclusion. Abbreviation: VAS, visual analog scale.
      Of the included patients, 234 (76%) were female, the mean age was 61±8 years, and the mean total MHQ score at baseline was 60±15. Table 1 shows all baseline characteristics of the included patients. We compared the baseline characteristics of the included patients (responders) to the patients who did not complete all questionnaires (nonresponders) and only found that the included patients had a shorter duration of symptoms (responders: median, 9; interquartile range, 5-24; nonresponders: median, 12; interquartile range, 6-24) (supplemental table S1, available online only at http://www.archives-pmr.org/).
      Table 1Patient characteristics at baseline
      Baseline CharacteristicsQuestionnaire

      Range (If Applicable)
      All Included Patients (N=308)Satisfied With Outcomes (n=141)Less Satisfied With Outcomes (n=167)Effect SizeP Value
      Age (y), mean ± SD61±861±761±8.781
      Sex, n (%).712
       Female234 (76)109 (77)125 (75)
      Hand dominance, n (%).683
       Right274 (89)124 (88)150 (90)
       Left20 (6)11 (8)9 (5)
       Both14 (5)6 (4)8 (5)
      Affected hand, n (%).525
       Right130 (42)59 (42)71 (43)
       Left141 (46)68 (48)73 (44)
       Both37 (12)14 (10)23 (14)
      Dominant hand affected, n (%)126 (41)59 (42)67 (40).849
      Duration of symptoms (mo), median (interquartile range)9 (5-24)8 (4-24)12 (6-24).454
      Workload, n (%).628
       Not employed120 (39)54 (38)66 (40)
       Light62 (20)31 (22)31 (19)
       Moderate93 (30)44 (31)49 (29)
       Severe33 (11)12 (9)21 (13)
      MHQ score, mean ± SD0-10060±1563±1557±150.37.001
      PHQ score, mean ± SD0-121.2±2.20.9±2.01.4±2.3−0.23.045
      PCS score, mean ± SD0-5211±910±813±10−0.35.002
      B-IPQ score, mean ± SD0-8051±950±1052±8−0.23.044
      CEQ Expectancy Score, mean ± SD3-2718±520±417±50.67<.001
      CEQ Credibility Score, mean ± SD3-2721±422±420±40.47<.001
      Abbreviations: B-IPQ, Brief Illness Perception Questionnaire; PCS, Pain Catastrophizing Scale; PHQ, Patient Health Questionnaire-4.
      Figure 2 shows the distribution of satisfaction on the 5-point Likert scale and the division into the 2 categories; of the 308 patients, 141 (46%) were satisfied with treatment outcomes, while 167 (54%) were less satisfied with treatment outcomes.
      Figure thumbnail gr2
      Fig 2Distribution of satisfaction with treatment outcomes using the original 5-point scale and the distribution of dichotomized satisfaction with treatment outcomes.
      Patients that were less satisfied with treatment outcomes reported worse MHQ score, lower expectations of the treatment, and less treatment credibility at baseline than patients who were satisfied with treatment outcomes (see table 1). Also, patients who were less satisfied scored worse on psychological distress, pain catastrophizing, and illness perceptions.
      While several baseline variables were associated with satisfaction with outcome in the univariable analysis (see table 1), higher CEQ Expectancy Score was the only significant variable associated with higher probability of being satisfied with treatment outcomes in the multivariable analysis (OR, 1.15; 95% confidence interval, 1.07-1.25) (table 2). This OR indicates that patients with 1 point more on the CEQ Expectancy Score have a 15% increase in odds of being satisfied with treatment outcomes.
      Table 2Multivariable logistic regression analysis on satisfaction with treatment outcomes
      Multivariable Logistic RegressionOR (95% CI)
      Age1.01 (0.97-1.05)
      Sex, male0.77 (0.41-1.44)
      Dominant hand affected1.15 (0.70-1.89)
      Duration of symptoms1.01 (1.00-1.02)
      Workload
       Light1.21 (0.59-2.48)
       Moderate1.15 (0.57-2.30)
       Severe1.02 (0.39-2.60)
      MHQ score1.02 (1.00-1.04)
      PHQ score1.00 (0.86-1.14)
      PCS score0.99 (0.95-1.02)
      B-IPQ score1.02 (1.00-1.04)
      CEQ Expectancy Score1.15 (1.07-1.25)
      P≤.001.
      CEQ Credibility Score1.03 (0.95-1.12)
      Abbreviations: B-IPQ, Brief Illness Perception Questionnaire; CI, confidence interval; PCS, Pain Catastrophizing Scale; PHQ, Patient Health Questionnaire-4.
      P≤.001.
      We visualized the effect of the CEQ Expectancy Score on satisfaction with treatment outcomes on the original scale in figure 3, showing a linear trend. Additionally, the likelihood ratio test showed that the model with nonlinear effects of the CEQ Expectancy Score did not have significantly better fit (P=.23) than the model with the CEQ Expectancy Score as a linear term. Therefore, we used the linear term of CEQ Expectancy Score in all analyses and were not able to find an optimum.
      Figure thumbnail gr3
      Fig 3Box-and-whisker plot of CEQ Expectancy Score (range, 3-27) per satisfaction category. The horizontal line represents the median, and boxes represent the first and third quartile. The whiskers represent 1.5 times the interquartile range from the first and respectively third quartile.
      Based on the variance inflation factor, we did not find an indication for multicollinearity in the multivariable logistic regression model.

      Mediation analysis

      Based on the results from the multivariable logistic regression analysis, we hypothesized that patients with a higher CEQ Expectancy Score would also have a higher total MHQ score at 3 months and would therefore be more satisfied. To test this hypothesis, we performed a post hoc mediation analysis. We found that only 33% of the effect of CEQ Expectancy Score on satisfaction with treatment outcomes was because of total MHQ score at 3 months (fig 4). The remaining 67% of the effect of expectations can either be explained by a direct effect on satisfaction or by an indirect effect through another factor that was not measured. This indicates that a better MHQ score at 3 months can only partially explain the association between CEQ Expectancy Score and satisfaction with treatment outcomes.
      Figure thumbnail gr4
      Fig 4Mediation model. The relation between CEQ Expectancy Score and satisfaction with treatment outcomes was mediated by the total MHQ score at 3 months. The standardized regression coefficients are reported from the regression of CEQ Expectancy Score on total MHQ Score at 3 months and the regression of CEQ Expectancy Score and total MHQ Score at 3 months on satisfaction with treatment outcomes. All regression analyses were corrected for total MHQ score at baseline. The indirect effect (0.119) was divided by the total effect (0.365) of CEQ Score on satisfaction with treatment outcomes to obtain the proportion mediated (33%).

      Discussion

      In this study, we found that patients with more positive expectations of the treatment outcome are more likely to be satisfied with treatment outcomes after 3 months of nonoperative treatment for CMC-1 OA. Additionally, we found that only one-third of this effect was because of better treatment outcomes at 3 months.
      Previous studies on other types of osteoarthritis reported that patients with higher expectations have better treatment outcomes such as pain and function.
      • Filbay S.R.
      • Judge A.
      • Delmestri A.
      • Arden N.K.
      COASt Study Group
      Evaluating patients' expectations from a novel patient-centered perspective predicts knee arthroplasty outcome.
      • Gandhi R.
      • Davey J.R.
      • Mahomed N.
      Patient expectations predict greater pain relief with joint arthroplasty.
      • Jain D.
      • Bendich I.
      • Nguyen L.L.
      • et al.
      Do patient expectations influence patient-reported outcomes and satisfaction in total hip arthroplasty? A prospective, multicenter study.
      • Jain D.
      • Nguyen L.L.
      • Bendich I.
      • et al.
      Higher patient expectations predict higher patient-reported outcomes, but not satisfaction, in total knee arthroplasty patients: a prospective multicenter study.
      • Judge A.
      • Cooper C.
      • Arden N.K.
      • et al.
      Pre-operative expectation predicts 12-month post-operative outcome among patients undergoing primary total hip replacement in European orthopaedic centres.
      • Lingard E.A.
      • Sledge C.B.
      • Learmonth I.D.
      Kinemax Outcomes Group
      Patient expectations regarding total knee arthroplasty: differences among the United States, United Kingdom, and Australia.
      • Mahomed N.N.
      • Liang M.H.
      • Cook E.F.
      • et al.
      The importance of patient expectations in predicting functional outcomes after total joint arthroplasty.
      This is in agreement with our finding that higher expectations are associated with a higher total MHQ score at 3 months. In addition, we found a positive association between higher expectations and satisfaction with treatment outcomes, which is not completely in line with previous studies. For example, Jain,
      • Jain D.
      • Bendich I.
      • Nguyen L.L.
      • et al.
      Do patient expectations influence patient-reported outcomes and satisfaction in total hip arthroplasty? A prospective, multicenter study.
      Mahomed,
      • Mahomed N.N.
      • Liang M.H.
      • Cook E.F.
      • et al.
      The importance of patient expectations in predicting functional outcomes after total joint arthroplasty.
      and Neuprez
      • Neuprez A.
      • Delcour J.P.
      • Fatemi F.
      • et al.
      Patients' expectations impact their satisfaction following total hip or knee arthroplasty.
      and colleagues also reported an association between higher expectations and satisfaction with treatment outcomes after orthopedic surgery, while several authors reported a negative association between expectations and satisfaction
      • Soroceanu A.
      • Ching A.
      • Abdu W.
      • McGuire K.
      Relationship between preoperative expectations, satisfaction, and functional outcomes in patients undergoing lumbar and cervical spine surgery: a multicenter study.
      or suggested that it would be better to lower expectations.
      • Marks M.
      • Audige L.
      • Reissner L.
      • Herren D.B.
      • Schindele S.
      • Vliet Vlieland T.P.
      Determinants of patient satisfaction after surgery or corticosteroid injection for trapeziometacarpal osteoarthritis: results of a prospective cohort study.
      ,
      • Frouzakis R.
      • Herren D.B.
      • Marks M.
      Evaluation of expectations and expectation fulfillment in patients treated for trapeziometacarpal osteoarthritis.
      ,
      • Jain D.
      • Nguyen L.L.
      • Bendich I.
      • et al.
      Higher patient expectations predict higher patient-reported outcomes, but not satisfaction, in total knee arthroplasty patients: a prospective multicenter study.
      Possibly, these different findings may be explained by different treatments, different diseases (eg, hip or knee OA), different questionnaires to assess expectations, or different pretreatment counseling. However, our results suggest that it would be better to optimize expectations to improve satisfaction and, to a lesser extent, improve treatment outcomes. A trial evaluating effects of different expectation management strategies of clinicians might provide valuable insights on how to address patients’ expectations of their treatment.
      Perhaps, the time point where patients completed the CEQ may explain why we found a positive association between treatment outcome expectations and satisfaction with outcomes. Patients in our study completed the CEQ after the first consultation with the hand surgeon. It could be that surgeons know from experience which patients will respond well to nonoperative treatment and will therefore provide individualized information on the expected results of the treatment to patients. This could in turn influence the CEQ Expectancy Score in individual patients. However, in our analysis, we controlled for patient characteristics, patient-rated hand function, and patient mindset and still found no other predictive baseline factors for satisfaction with treatment outcomes than CEQ Expectancy Score.

      Study limitations

      A strength of this study is the large sample size in a population-based cohort. Second, to our knowledge, this is the first study investigating satisfaction with treatment outcomes after exercise therapy, an orthosis, or both for CMC-1 OA. Third, by performing a mediation analysis, we were able to provide more insight into the mechanism of the association we found.
      However, our study also has several limitations. Satisfaction with treatment outcomes is a complex construct that is difficult to measure and difficult to fully comprehend, as mentioned in an editorial by Ring and Leopold.
      • Ring D.
      • Leopold S.S.
      Editorial-measuring satisfaction: can it be done?.
      Ring and Leopold describe that there are many reasons why one patient can be satisfied with the treatment outcome and another patient may be dissatisfied while having the same treatment outcome. However, although satisfaction with treatment result is a difficult construct and influenced by many factors, it is also a very important and relevant outcome measure in striving for patient-centered care. Therefore, future studies investigating the underlying mechanisms that determine a patient’s satisfaction with treatment outcome are needed to provide patient-centered care that is tailored to the patient’s needs.
      Another limitation is that in this study, we used a self-designed questionnaire to assess satisfaction with treatment outcomes, which has not been validated yet. However, to our knowledge, there are no validated patient-reported outcome measures available to measure satisfaction with treatment outcomes for patients with hand and wrist disorders. The questionnaire we used and the dichotomization of our outcome measure are very similar to questionnaires and analyses used in previous studies, which allows us to compare our results with other studies.
      • Marks M.
      • Audige L.
      • Reissner L.
      • Herren D.B.
      • Schindele S.
      • Vliet Vlieland T.P.
      Determinants of patient satisfaction after surgery or corticosteroid injection for trapeziometacarpal osteoarthritis: results of a prospective cohort study.
      ,
      • Frouzakis R.
      • Herren D.B.
      • Marks M.
      Evaluation of expectations and expectation fulfillment in patients treated for trapeziometacarpal osteoarthritis.
      However, to avoid dichotomization and the loss of information as a result, a validated patient-reported outcome measure for satisfaction with treatment outcomes with a continuous scale is needed to further optimize personalized care for individual patients.
      Previous studies have reported that the context of treatment (eg, communication style of the health care provider) also affects satisfaction with treatment outcomes
      • Di Blasi Z.
      • Harkness E.
      • Ernst E.
      • Georgiou A.
      • Kleijnen J.
      Influence of context effects on health outcomes: a systematic review.
      ,
      • Testa M.
      • Rossettini G.
      Enhance placebo, avoid nocebo: how contextual factors affect physiotherapy outcomes.
      ,
      • Rossettini G.
      • Carlino E.
      • Testa M.
      Clinical relevance of contextual factors as triggers of placebo and nocebo effects in musculoskeletal pain.
      ,
      • Suarez-Almazor M.E.
      • Looney C.
      • Liu Y.
      • et al.
      A randomized controlled trial of acupuncture for osteoarthritis of the knee: effects of patient-provider communication.
      ; hence, a limitation is that we did not include a measure for treatment context in our study. Future studies should therefore include such measures in their analysis when studying satisfaction with outcomes, as well as study how to incorporate this into clinical practice.
      In our study we found that more positive expectations are associated with higher satisfaction with treatment outcomes after 3 months of nonoperative treatment for CMC-1 OA, which can only partially be explained by better treatment outcomes. This suggests that optimizing expectations might improve satisfaction and, to a lesser extent, improve treatment outcomes. However, future experimental studies are needed to determine whether modifying expectations of patients receiving nonoperative treatment for CMC-1 OA, for example, by framing pretreatment information in a positive manner, will positively affect satisfaction and treatment outcomes.

      Conclusions

      This study demonstrates that patients with higher treatment outcome expectations are more likely to be satisfied with treatment outcomes after 3 months of nonoperative therapy for CMC-1 OA. Health care providers treating patients nonoperatively for CMC-1 OA should be aware of the importance of expectations and should take this into account in pretreatment counseling.

      Suppliers

      • a.
        Mplus, version 8.1; Muthén & Muthén.
      • b.
        R statistical computing, version 3.5.2; The R Project.

      Acknowledgments

      The collaborators of the Hand-Wrist Study Group are R.A.M. Blomme, B.J.R. Sluijter, D.J.J.C. van der Avoort, A. Kroeze, J. Smit, J. Debeij, E.T. Walbeehm, G.M. van Couwelaar, G.M. Vermeulen, J.P. de Schipper, J.F.M. Temming, J.H. van Uchelen, H.L. de Boer, K.P. de Haas, K. Harmsen, O.T. Zöphel, R. Feitz, J.S. Souer, R. Koch, S.E.R. Hovius, T.M. Moojen, X. Smit, R. van Huis, P.Y. Pennehouat, K. Schoneveld, Y.E. van Kooij, R.M. Wouters, P. Zagt, F.J. van Ewijk, J.J. Veltkamp, A. Fink, W.A. de Ridder, H.P. Slijper, R.W. Selles, J.T. Porsius, J. Tsehaie, R. Poelstra, M.C. Jansen, M.J.W. van der Oest, P.O. Sun, L. Hoogendam, J.S. Teunissen, Jak Dekker, M.L. Jansen-Landheer, and M.H.P. ter Stege.

      Supplementary data

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