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BMC Family Practice

Open AccesResearch article

Family practice nurses supporting self-management in olderpatients with mild osteoarthritis: a randomized trial

Raymond Wetzels*1

, Chris van Weel2

, Richard Grol1

and Michel Wensing1

Address: 1Centre for Quality of Care Research (WOK), Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands and2Department of Family Practice, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands

Email: Raymond Wetzels* - [email protected]; Chris van Weel - [email protected]; Richard Grol - [email protected];Michel Wensing - [email protected]

* Corresponding author

Abstract

Background: Supporting self-management intends to improve life-style, which is beneficial for

patients with mild osteoarthritis (OA). We evaluated a nurse-based intervention on older OA

patients' self-management with the aim to assess its effects on mobility and functioning.

Methods: Randomized controlled trial of patients ( 65 years) with mild hip or knee OA from ninefamily practices in the Netherlands. Intervention consisted of supporting patients' self-management

of OA symptoms using a practice-based nurse. Outcome measures were patients' mobility, using

the Timed Up and Go test (TUG), and patient reported functioning, using an arthritis specific scale

(Dutch AIMS2 SF).

Results: Fifty-one patients were randomized to the intervention group and 53 to the control

group. Patient-reported functioning improved on four scales in the intervention group compared

to one scale in the control group. However, this result was not significant. Mobility improved inboth groups, without a significant difference between the two groups. There were no differences

between the groups regarding consultations with family physicians or physiotherapists, or

medication use.

Conclusion: A nurse-based intervention on older OA patients' self-management did not improve

self-reported functioning, mobility or patients' use of health care resources.

BackgroundIn our aging population osteoarthritis (OA) is a highlyprevalent chronic disease, which has a high impact onburden of disease, quality of life, and use of healthcare.

Worldwide estimates are that 10% of men and 18% ofwomen aged 60 years have symptomatic OA [1]. In earlystages clinical management of OA is targeted at improvingpatients' self-management [2-5], losing weight [6], physi-cal exercise [7-11] and adequate use of analgesics. But,medicalization of OA should be avoided. Patients' self-

management may improve their life-style and thereforehealth outcomes, analogue to diabetic patients [12].Healthcare systems face the challenge to enhance self-management in OA patients on a sufficiently large scale sothat all patients are actually reached and helped. Barriersmay be that improving patients' life-style often requiressubstantial investment of both patients' and health pro-fessionals' time, as many education programmes require alarge number of sessions [13]. And, the health behaviorsin older patients tend to be reserved, as they attribute

Published: 28 January 2008

BMC Family Practice 2008, 9:7 doi:10.1186/1471-2296-9-7

Received: 12 August 2007Accepted: 28 January 2008

This article is available from: http://www.biomedcentral.com/1471-2296/9/7

2008 Wetzels et al; licensee BioMed Central Ltd.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0),which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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BMC Family Practice 2008, 9:7 http://www.biomedcentral.com/1471-2296/9/7


many complaints towards getting older, and consequentlyarthritis symptoms are underreported [14]. Involvingpractice-based nurses in the management of OA ensuresthat this care is delivered closely to the patient. A recentreview showed that substituting physicians for appropri-

ately trained nurses could produce as highly quality careas primary care doctors and achieves as good outcomes forpatients [15]. The availability of skilled nurses is limitedand nursing time invested in any intervention needs to beexamined critically. Therefore we wondered whether a sin-gle individual session with a trained nurse, which wasfocused on supporting patients' self-management, wouldbe effective in OA patients. On the basis of previousresearch on changing life style behavior by family physi-cians (FPs), we expected a small but relevant change inpatient behavior [16]. The aim of this proof of principlestudy was to evaluate the clinical effectiveness of a singlesession nurse-based intervention for enhancing self-man-

agement in older patients with mild OA.

Methods

Study Population

This study was a patient randomized controlled trial,which was performed between April 2004 and January2005. This trial has not been registered beforehand in apublicly accessible trial registry as it was performed beforeprospective registering of these trials became obliged. Theethical committee of the Radboud University MedicalCentre Nijmegen gave approval for the study.

The trial was based on the practice populations of seven-

teen FPs from nine urban non-academic practices in theEastern region of the Netherlands. Patients were eligible ifthey were aged 65 or older and had been clinically diag-nosed with OA of the hip or knee. The OA diagnosisneeded to be registered in patient's practice medical his-tory record as free text or as ICPC-code L89 (OA of theknee) or L90 (OA of the hip). Patients were excluded ifthey had undergone a hip or knee replacement operation,or had been referred for it or when their GP thought they

were not suitable for participating (for example because ofsevere psychosocial circumstances, or a terminal disease).No further classification of degree of OA was made. Aninformed consent letter was sent by the GP and patients

were included after they had replied positively.

Randomization

An independent statistician made randomization lists inadvance for each practice. To ensure similar numbers ofpatients from different practices in each group, block-ran-domization (blocks of two) was used. These randomiza-tion lists were represented in nine different spreadsheets.Every patient who entered the study was given a numberthat represented the order of entrance in the study for thatpractice. Subsequently, the number of entrance per prac-

tice in the spreadsheet was used to randomly assign thepatient to intervention or control group. This was proce-dure was performed by a research assistant who wasblinded for patients' characteristics.

InterventionThe intervention consisted of education and self-manage-ment of OA symptoms. It was performed by a nurse andaimed to change life style behavior, by improving mobil-ity and physical functioning. On a time-scale the interven-tion consisted of three parts. Firstly, patients had toprepare for the home visit of the nurse, using an educa-tional leaflet about osteoarthritis (developed by the DutchCollege of General Practitioners) and a booklet withhealth-status charts. The health-status charts were basedon the Wonca COOP-charts [17]. The patients needed tofill out their level of exercise, pain-level and their impair-ments prior to the nurse home visit. The charts were dis-

cussed during a 30-minute nurse home visit; this is thesecond part of the intervention. In this home visit patientsgot insight in their own OA symptoms. Subsequently,they agreed to try to change one of four life style items(physical exercise, weight loss, use of a walking aid andhow to use over the counter (pain) medication). The thirdpart of the intervention was a follow-up phone call afterapproximately 3 months. In this phone call the nurse eval-uated to what extent the patient had been able to adapt hislife style change and subsequently what possibly was nec-essary to maintain this change.

The nurse had undergone a certified education in rheuma-

tology. Patients in the control group received only theeducational leaflet about osteoarthritis.

Outcome measures

Primary outcome measurements were 4 subscales of theDutch version AIMS2 SF [18] and the Timed Up and Gotest (TUG) [19]. The Dutch-AIMS2 SF is an arthritis spe-cific health status scale and we used the following sub-scales: physical functioning, pain, social functioning andmood symptoms, all scored on a 5-point scale. The AIMS2SF has been validated for OA in the USA [20] and Ger-many [21]. The TUG is an objective outcome measure formobility in older patients: the patient is observed and

timed while (s)he rises from a chair, walks 3 meters, turns,walks back, and sits down again. Secondary outcomemeasures were patient-reported number of contacts withthe GP and physiotherapist and whether they used painmedication (over the counter (OTC) or prescribed).

All outcome measures were collected at baseline and after6 months. Baseline and post-intervention data wereobtained in two ways. A patient questionnaire was used tocollect all patient reported outcomes. The TUG was per-formed by the nurse in the intervention group and by a
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research assistant in the control group for the baselinedata. A research assistant measured in all patients thepost-intervention TUG, at this stage he was blinded forintervention-control condition.

Power calculationTo estimate sample size, a power calculation was per-formed using the subscale lower body limitations of theDutch AIMS2 SF (Arthritis Impact Measurement ScalesShort Form) [18,20] and the Timed Up and Go test [22].

We wanted to detect a small to medium effect (MeanStandardized Difference of 0.4), with alpha 0.05 and beta0.20. We needed to include 49 patients per group [23].

Anticipating on refusal rates and loss to follow-up weapproached 158 patients.

Analysis

In the analysis, follow-up scores of patients were adjusted

for baseline scores [24]. Independent variables were there-fore randomization (intervention or control group) andthe baseline scores of the respective dependent variables.Data from dropouts and lost to follow-up cases was notavailable, therefore only cases with data from baselineand after 6 months were included. The analyses were per-formed using SPSS (version 12) software. Data werechecked for normality of residuals. For the primary out-come measure Timed Up and Go test we used a logisticregression technique. TUG times were divided into twoclinically relevant groups (=12 seconds) on thebasis of literature [25]. Dutch AIMS2 SF scales were ana-lyzed with a linear regression technique. The secondary

outcome measures (GP visits, physiotherapist visits anduse of pain medication) were analyzed using a chi-squaretest. We did not substitute missing values in any of thescales.

Results

A total of 158 patients were sent an informed consent let-ter and a questionnaire. After one reminder 125 patients(79.1%) responded. Of these 104 patients were includedand randomly assigned (Figure 1). Fifty-one patients wereallocated to the intervention group and 53 were allocatedto the control group. Fifty-four patients (of the initial 158)could not be included: 33 did not respond to the study

invitation, 7 forgot to fill in their names, 12 did not giveinformed consent, 1 moved to another region and 1 died.

Those excluded were not significantly different in age andgender compared to participants. At baseline no differ-ences in self-reported characteristics between interventionand control group patients were detected (Table 1). Dueto several reasons seven patients withdrew their participa-tion during the study (motivation problems, moved else-

where, hip/knee surgery, too severe problems of co-morbidity and treatment by a geriatric specialist) and ninepatients did not respond to the final patient self-assess-

ment questionnaire (Figure 1). No differences in self-reported characteristics were found compared to post-intervention responders. Main results are described belowand schematically presented in Table 2.

Primary outcomesWhen considering patients' self-reported functioning,intervention patients' mean scores changed towards betterfunctioning. In the control group three out of four sub-scales in the before-after measurements went in the differ-ent direction, thus a worsening in function. However,none of the subscales in the intervention group had a sig-nificant improvement compared to the control group(table 2).

With respect to the Timed Up and Go test the shifttowards the group 12 seconds in the intervention group

was more or less equal to the shift in the control group.

One third of the intervention patients (35%) performedthe TUG below 12 seconds at baseline and half of thepatients after the intervention (50%). For the controlgroup this was 41% and 55% respectively.

Secondary outcomes

Intervention patients did not visit their GP or physiother-apist more often compared to the control group. In theintervention group 6/40 (15%) patients had 3 or more

visits in the past half-year to their GP, compared to 7/48(14.6%) patients in the control group (p = 0.81). 8/40(20%) patients in the intervention group received physio-therapist treatment for their osteoarthritis complaints,

compared to 6/48 (12.5%) patients in the control group(p = 0.28). Pain medication use did not significantly differbetween the two groups (p = 0.49). However, there was anincrease in medication use in the intervention group. Inthe intervention group at baseline 17/40 (42.5%) patientsused medication for osteoarthritis pain, whereas post-intervention this was 22/40 (55%) patients. In the controlgroup the numbers were respectively, 24/48 (50%) and23/48 (47.9%).

Discussion

This nurse-based intervention did not improve an olderOA patient's mobility and functional status, although a

non-significant trend towards better functional status wasobserved. In both study groups patients showed animprovement in functional status. There were no signs ofnegative side effects, such as more pain among interven-tion patients, and no signs of increased numbers of visitsto the GP or physiotherapist. Numbers were small andonly powered to identify a medium difference, and sothere is a possibility of a type 2 error. If the trend in effectsobserved were confirmed in a larger trial, and if such smalleffects in a common problem such as OA proved to be

worthwhile in the long-term, then the intervention might
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still eventually prove to be effective. However, it is clear

from our results that the intervention did not achieve clearor substantial effects. Several considerations for thesefindings may appear, such as the time between interven-tion and final measurement may have been to short todetect differences. Also, the intervention itself might havebeen too simple to detect differences in these outcomemeasures. However, our results are consistent with a studysimilar to ours in the same time period [26]. The interven-tion in this study was slightly more extensive, and theirfollow-up was 6 months longer; but their findings werethat a nurse-led education programme for patients with

osteoarthritis (40 years or older) did not benefit these

patients. On the other hand, another study showed that anurse-led intervention aimed at improving non-pharma-cologic treatment modalities instead of NSAIDs was effec-tive for OA patients (aged 60 years or older) in primarycare [27]. In this study a structured algorithm was usedand patients were individually and regularly followed up.

A recent trial of self-management of arthritis in patients50 years and older showed reduced anxiety and improvedpatients' perceived self efficacy in managing symptoms,but also no significant effects on pain, or physical func-tioning [28].

Figure 1
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The limitations of our study could have interfered withthe results. Larger groups, less dropout and longer follow-up might have provided more favorable results. The out-come measures had a number of missing values, despiteour efforts to keep the measurements simple and short.

The Dutch AIMS2 SF has been validated for rheumatoidarthritis patients, but not for OA patients. However, theUS and German version of the AIMS2 SF have been vali-dated for OA patients, with the conclusion of the AIMS2SF being a reliable and valid instrument to assess the qual-ity of life in primary care patients suffering from OA [21].

The validity and reliability of the TUG might be compro-mised by the fact that the test was performed at home, ondifferent chairs, and by different observers. At baseline theassessors of TUG times were not blinded for the assign-ment of subjects to treatment group. There is some evi-dence that the type of chair does not matter [29], but thesefactors may have interfered in the validity of the valuesand may have introduced a bias.

ConclusionNon-extensive interventions to improve self-managementand life style in OA are, on average, not effective. Thecounseling may need to be targeted more explicitly toindividual problems in order to be successful. Perhapscounseling is only useful for a subgroup of OA patients,such as those with insufficient physical exercise who havea minimum of motivation to increase their physical activ-ities. Furthermore, regular follow up could contributesubstantially to the effectiveness of a short intervention.Finally, if a non-extensive intervention is not effective in a

patient, more intensive interventions should be availableas part of a larger care programme for osteoarthritis. Otherhealth professionals may need to become involved in thedelivery of more intensive interventions, such as special-ized nurses (rather than generalistic primary care nurses asin this study) and physiotherapists. It is crucial that theeffectiveness and feasibility of such interventions and careprogrammes are tested, before wide-scale implementationis promoted.

Table 2: Primary outcome measure (Dutch AIMS-SF)

Outcome measure Intervention Control Comparison$

Pre Post Pre Post p

Range Mean SD Mean SD Mean SD Mean SD

AIMS*# Physical 735 15.25 4.61 14.56 4.52 14.20 4.40 14.40 4.74 0.36

Symptoms 315 10.10 3.05 8.86 3.34 9.65 3.07 8.87 3.16 0.96

Social 420 11.94 2.70 11.40 2.91 11.43 2.42 11.88 2.76 0.31

Affect 525 12.27 3.35 11.19 3.95 11.23 3.05 11.48 3.64 0.22

* AIMS: The lower the scores, the better the functioning.# Adjusted for baseline scores.$ Using linear regression technique

Table 1: Patient reported characteristics of included patients at baseline (n = 104)

Characteristic Intervention N = 51 Control N = 53 T Chi2 p-value

% n % n

Gender

F 76.5 39 75.5 40

M 23.5 12 24.5 13 0.014 0.91

Type of osteoarthritis

Knee 52.9 27 54.7 29

Hip 17.6 9 22.6 12

Both 29.4 15 22.6 12 0.795 0.67

Education

Primary or lower secondary 54.0 27 50.0 25

Upper secondary or further 46.0 23 50.0 25 0.160 0.69

Age SD SD

Mean 75.63 6.68 73.47 6.01 -1.73 0.09

Median 74 73
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Competing interestsThe author(s) declare that they have no competing inter-ests.

Authors' contributions

RW carried out the study and drafted the manuscript. RGand CvW participated in the concept and design of thestudy and were important in revising the manuscript. MWparticipated in the design of the study, helped in coordi-nating the study and drafting the manuscript. All authorsread and approved the final manuscript.

AcknowledgementsWe gratefully acknowledge Janine Liefers and Karin de West for assisting

with the data-analysis and for visiting the elderly at home. The Netherlands

Organisation for Health Research and Development funded this study

(ZonMW, number 920-03-252).

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