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Rheumatology Advance Access originally published online on February 8, 2008
Rheumatology 2008 47(3):368-374; doi:10.1093/rheumatology/kem374
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© The Author 2008. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

Predictors of onset and progression of knee pain in adults living in the community. A prospective study

C. Jinks, K. P. Jordan, M. Blagojevic and P. Croft

Primary Care Musculoskeletal Research Centre, Primary Care Sciences, Keele University, Keele, UK.

Correspondence to: C. Jinks, Primary Care Musculoskeletal Research Centre, Primary Care Sciences, Keele University, Keele, Staffordshire ST5 5BG, UK. E-mail: c.jinks{at}cphc.keele.ac.uk


   Abstract
Top
 Abstract
Introduction
 Patients and methods
 Results
 Discussion
 Acknowledgements
 References
 
Objective. To investigate determinants of the onset and progression of knee pain in a population-based sample of people aged ≥50 yrs.

Methods. Prospective cohort study of 2982 people registered with three general practices in North Staffordshire, UK. Using questionnaire surveys at baseline and 3 yrs, demographic, knee-related and general health factors were assessed for their relationship with onset of new knee pain, and progression from non-severe to severe knee pain.

Results. Response rates were 77% (baseline) and 75% (follow-up). Baseline factors significantly associated with onset of knee pain were knee injury [odds ratio (OR) 1.6, 95% CI 1.2, 2.2], depression (OR 1.4, 95% CI 1.1, 1.8), widespread pain (OR 1.5, 95% CI 1.1, 1.9 compared with no pain) and younger age. Onset of severe knee pain was associated most strongly with obesity (OR 2.9, 95% CI 1.7, 5.1) and physical limitations (OR 2.5, 95% CI 1.5, 4.1), and with widespread pain, older age, female gender and comorbidity. The strongest independent predictors of progression from non-severe to severe knee pain were chronicity (OR 3.1, 95% CI 2.1, 4.6), previous use of health care (OR 2.2, 95% CI 1.5, 3.3) and obesity (OR 2.1, 95% CI 1.2, 3.6).

Conclusion. In addition to a focus on obesity, there is potential for primary prevention of knee pain by tackling knee injuries and treating depression. Other factors are likely to determine whether the knee pain then progresses. An area for future research is the ineffectiveness of current health care in halting or reversing progression of knee pain at a population level.

KEY WORDS: Knee pain, Knee OA, KNEST, Knee Joint, Prospective studies, Follow-up studies, Disability, Incidence, Disease progression, Population survey


   Introduction
Top
 Abstract
 Introduction
Patients and methods
 Results
 Discussion
 Acknowledgements
 References
 
Osteoarthritis (OA) is the commonest cause of disability in older people, and its commonest manifestation is joint pain, with the knee being the most frequent site of disabling pain. Nearly half of all adults aged ≥50 living in the community report knee pain in a 1-yr period, with a quarter suffering from severe and disabling pain [1]. We have previously estimated from a prospective population-based cohort study that onset of new knee pain in older adults is accompanied by a substantial decline in their physical function within a 3-yr period [2]. Preventing onset of knee pain and its progression among older adults is therefore relevant to current health policy, which aims to maintain independence in older adults and prevent unnecessary admissions to hospital, and which focuses on ‘healthy ageing’ [3–5]. Although the burden of the problem in the community is now well described from cross-sectional studies [1, 6–8], we know little about the associated risk factors for its onset or decline in the general older population [9].

Risk factors for radiographic OA are now well documented [10–12] and risk factors for onset differ from those for its progression [13, 14]. One explanation is that determinants of the initial event (for example, damage or injury) may differ from factors that influence the bone or cartilage response to that injury [13]. Risk factors for onset of many regional musculoskeletal pain syndromes may differ from predictors of their progression and chronicity, and one explanation may be that local mechanical stress and injury determine the onset of pain and its location, whereas other factors (such as concurrent chronic pain elsewhere in the body or psychological distress) influence whether the pain becomes chronic or not. However, in the case of knee pain in older people, this is contradicted by the observation that obesity (a source of mechanical stress on the knees) has a stronger influence on progression to a severe or disabling problem rather than on the onset of the problem [15].

Furthermore, prospective studies of knee pain in the general population are rare [9, 16]. In the current article, we investigate the pattern of potential risk factors (mechanical, psychological, social and demographic) for knee pain and associated disability in older people, and how they may differ between onset and progression. The practical importance of this is that risk factors for onset might be better addressed as part of more general primary prevention in the community (injury prevention for example), whereas risk factors for progression might be appropriately tackled as part of secondary prevention when patients present to a health care professional (treatment of concurrent depression, for example). Identifying and distinguishing risk factors for onset and progression of knee pain in older people would help to shape and develop targeted strategies for primary and secondary prevention in the general population and primary care.

The specific objective of the current article was to investigate differences between potential determinants of the onset and progression of knee pain in a population-based sample of people aged ≥50 yrs.


   Patients and methods
Top
 Abstract
 Introduction
 Patients and methods
Results
 Discussion
 Acknowledgements
 References
 
This was a prospective cohort study, including a baseline questionnaire to all patients aged ≥50 registered at three general practices in North Staffordshire, UK and an identical follow-up questionnaire 3 yrs later sent to all subjects who responded to the baseline questionnaire and who were still registered with the practices. Approximately 98% of the British population is registered with a general practitioner (GP), making GP lists an appropriate sampling frame for a population study [17]. The study was approved by North Staffordshire Local Research Ethics Committee.

The questionnaires included instruments to measure demographic factors, knee-related characteristics and general health. The Knee Pain Screening Tool (KNEST) [1] is a validated measure for use in population-based surveys, containing six questions [18]. The question on knee pain asks whether the respondent has had pain in or around either knee in the last 12 months. Other questions identify the chronicity and laterality of knee pain, and GP and other health care use for knee pain.

The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) [19] was used to identify the severity of knee pain and disability. This measure contains 24 questions comprising three subscales (pain, stiffness and physical functioning). The WOMAC asks about pain due to arthritis in the last 48 h but we used a slightly modified version to ask respondents to think about ‘the amount of pain that you have experienced in your knee in the last 48 hours’. This minor change made the questionnaire relevant to people in the general population who had not consulted their GP or been given a diagnosis of OA and ensured that answers given were tailored to the knee rather than the lower limb. We have previously validated this modified WOMAC [20].

‘Severe knee pain’ was defined as the presence of any pain or physical functioning limitation on the WOMAC recorded as severe or extreme, and in this article, the phrase therefore refers to either severity of the pain or the presence of some related severe restriction in function or both [20].

General physical limitations were measured using the Short Form-36 (SF-36) generic health profile [21]. A physical limitation was indicated by reporting ‘Yes, limited a lot’ on at least one of the Physical Functioning scale items. Current evaluation of general health was also measured using an item from the SF-36 with a rating of health as poor or fair defined as an unfavourable evaluation. The Hospital Anxiety and Depression scale (HADS), [22] was used to determine depression. This is a well-validated psychological screening tool [23]. Responders scoring above the top tertile on the depression scale were considered most depressed.

Self-reported height and weight at baseline were used to determine BMI. BMI is calculated as weight in kilograms divided by the square of height in metres. BMI categories were defined according to the World Health Organization standard classification scheme [24]. A BMI of 20–24.9 was thus considered normal, a BMI <20 as underweight, a BMI of ≥25 and <30 as overweight and ≥30 as obese.

The extent of other joint pain was measured using a pain mannequin. Responders were asked to shade, on a blank mannequin, any ache or pain that had been experienced for one day or longer in the last month. This method has been previously validated for use in large-scale population surveys [25]. Pain in two or more regions was defined as pain in two joint sites including the neck, hand, low back, hip, foot and ankle.

Educational attainment was derived from a question at baseline which asked about full-time further education beyond school. Socioeconomic status was calculated using current or last job [26].

A further question asked subjects whether they consented to viewing of their medical records. This was included in the survey to enable determination of measures of consultation comorbidity. We linked the survey data to general practice consultation records in those persons who consented to such linkage. This linking is possible through the practices’ membership of the Keele General Practice Research Partnership. The practices in the partnership code morbidity presented during routine consultations, and the quality of this recording is high [27, 28] and subject to regular audit. The codes used are those of the Read Code system, a method of classification in widespread use in the UK National Health Service. Read Codes form a hierarchy of diagnostic and process of care codes, and diagnostic codes are grouped into chapters (e.g. musculoskeletal, mental health, circulatory). Dedicated staff access and download medical record data from the practices and make these anonymous for research analysis. Baseline comorbidity for each respondent was measured in two ways: first, the number of contacts with their GP in the 12 months prior to baseline; second, the number of diagnostic Read Code chapters for which the GP had entered a code for that person during those same 12 months.

There were three separate cohort analyses. Onset of knee pain was studied in the cohort of persons free of knee pain at baseline, and was defined as the subsequent presence of knee pain reported in the 3-yr follow-up survey. A separate analysis investigated development of severe knee pain at 3 yrs (‘onset of severe knee pain’) in this same subgroup of persons free of knee pain at baseline. Progression was studied in the cohort of persons who reported mild or moderate knee pain at baseline and was defined as the subsequent presence of severe knee pain (regardless of whether it was the same knee in which they reported pain at baseline) reported in the 3-yr follow-up.

Analysis
The three analyses (onset of any knee pain, onset of severe knee pain and progression of knee pain) followed a stepped format similar to that used in our earlier study of predictors of consultation [29]. Demographic, knee-related and general health factors at baseline (Fig. 1) were separately assessed for their relationship with any knee pain or severe knee pain at follow-up.


Figure 1
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  		FIG. 1. Baseline factors explored for their association with knee pain at 3 yrs.

 
First, unadjusted odds ratios (ORs) were calculated (with 95% CIs) to show the univariate association between each potential risk factor and 3-yr outcome. Second, the ORs were adjusted for age and gender and all the other factors within the same section (demographic, knee-related or general health) using multiple logistic regression with all variables entered simultaneously. This identified the main independent predictors of 3-yr outcome in each section. Then, in Step 3, age and gender, all significant predictors (P < 0.05) and all predictors with an OR >1.30 or <0.77 at Step 2 were combined across sections in one model, again using logistic regression with all variables entered simultaneously.

A final set of analyses included only those responders who gave consent for their medical records to be reviewed. The additional primary care consultation variables were added to the models derived in Step 3 to assess the influence of baseline consultation comorbidity on knee pain onset or progression, with the two variables entered separately.

The effect of comorbidity was also assessed by examining the interaction of obesity with depression in the final models. Differences in the strength of risk factors by age was assessed by reproducing the final models following stratification by age (<65, 65 and over).

Analysis was performed using SPSS 14.0 for Windows (SPSS Inc., Chicago, IL, USA).


   Results
Top
 Abstract
 Introduction
 Patients and methods
 Results
Discussion
 Acknowledgements
 References
 
A total of 8995 persons were sent a questionnaire at baseline to which 6792 responded. After adjusting for deaths and departures (i.e. people moving or errors in postal address) from the list, this represents a response of 77%. Of these 6792 subjects, 5784 were alive and still registered at the practices at follow-up and were sent a follow-up questionnaire to which 3907 responded and answered the KNEST knee pain question at both baseline and follow-up. The cohorts for analysis in the current article were drawn from this sample.

A total of 3253 responders also gave consent for medical record review. Analysis of significant predictors (based on demographic, knee and general health factors) just for these 3253 respondents gave identical conclusions as the analysis for the whole group (n = 3907). Those who answered the KNEST knee pain question at both baseline and follow-up were slightly younger (mean difference 1.8 yrs; 95% CI 1.3, 2.4) and had slightly better SF-36 scores (mean differences of between 3 and 6 points higher) than those who did not respond at follow-up or failed to complete the KNEST knee pain question at baseline or follow-up. However, they did not differ by gender or by their response to the baseline knee pain question.

For this article, we have excluded persons with severe knee pain at baseline (n = 925) and constructed two cohorts for analysis from the remainder: persons with no knee pain at baseline and therefore at risk of new onset of knee pain (n = 2059) and persons with mild to moderate knee pain at baseline and therefore at risk of progression (n = 923).

Predictors of onset of knee pain
As reported previously [2], among the 2059 persons with no knee symptoms at baseline, 24% subsequently reported any (mild or severe) knee pain and disability at 3 yrs (7% severe). The baseline factors significantly associated in the final model with subsequent onset of any knee pain at 3 yrs were previous knee injury (OR 1.59, 95% CI 1.17, 2.17), widespread pain (OR 1.47, 95% CI 1.14, 1.89 compared with no pain), depression (OR 1.40, 95% CI 1.07, 1.84) and younger age (50–64) (OR 1.52, 95% CI 1.18, 1.92 compared with age 65–74). Obesity had an association similar in size to that of depression but this was not statistically significant (Table 1). Comorbidity based on consultation was not significantly related to onset of pain in the subgroup consenting to medical record review.


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  		TABLE 1. Associations with onset of any (mild or severe) knee pain of demographic, knee-related and general health factors

 
Predictors of onset of severe knee pain
In the second analysis among persons with no knee symptoms at baseline, 144 (7%) had developed severe knee pain at 3-yr follow-up. The strongest predictor of subsequent severe knee pain in the univariate analysis was baseline general physical limitation (OR 4.49, 95% CI 3.02, 6.68). However, adjustment for other general health factors explained some of this effect and in the final multivariate model obesity was the strongest predictor (OR 2.91, 95% CI 1.67, 5.08). Other baseline factors independently associated with onset of severe knee pain were: self-reported general physical limitation (OR 2.49, 95% CI 1.53, 4.06), widespread pain (OR 1.88, 95% CI 1.18, 3.01), older age (OR 1.78, 95% CI 1.03, 3.09) and female gender (OR 1.67, 95% CI 1.11, 2.51) (Table 2). In the subgroup with consultation data, consulting about conditions in three or more Read Code chapters in the year prior to baseline survey was significantly associated with onset of severe or disabling knee pain (OR 1.66, 95% CI 1.05, 2.62).


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  		TABLE 2. Associations with onset of severe knee pain in those with no knee pain at baseline of demographic, knee-related and general health factors

 
Predictors of progression from non-severe to severe knee pain
Among 923 persons with non-severe knee pain at baseline, 176 (19%) reported severe knee pain at follow-up in either knee. The strongest independent predictors of progression to severe or disabling knee pain at 3 yrs in the multivariate model were: baseline chronicity (OR 3.06, 95% CI 2.06, 4.56), previous use of health services (OR 2.20, 95% CI 1.47, 3.30) and obesity (OR 2.08, 95% CI 1.22, 3.57). Modest but non-significant associations were observed for baseline unfavourable health evaluation (OR 1.56, 95% CI 0.99, 2.48), age 75+ (OR 1.92, 95% CI 0.98, 3.76), lower education levels (OR 1.52, 95% CI 0.77, 3.02) and lower socioeconomic class (OR 1.46, 95% CI, 0.88, 2.42). Widespread pain was not associated with progression to severe knee pain (OR 1.17, 95% CI 0.74, 1.84) in contrast to its link with onset of severe pain (Table 3). Consulting eight or more times during the year prior to baseline had a modest but non-significant relationship with progression (OR 1.39, 95% CI 0.77, 2.52).


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  		TABLE 3. Associations with progression (non-severe to severe) of knee pain of demographic, knee-related and general health factors

 
A summary of the factors related to the onset and progression of knee pain is presented in Table 4.


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  		TABLE 4. Summary of significant risk factors for onset and progression of knee pain in the general population of adults aged ≥50 yrs

 
Interaction of age, depression and obesity
There was no evidence of positive interaction between baseline depression and obesity on subsequent onset of either any or severe knee pain (data not shown). The separate effects were similar for onset of any pain, for depression in the absence of obesity (OR 1.60) and for obesity in the absence of depression (OR 1.65). Both these associations were stronger for the onset of severe knee pain, but for obesity substantially more so (OR 5.16) than depression (OR 2.58).

There were some differences in effect after stratification for age (<65 yrs vs ≥ 65 yrs) for onset, but not progression, of knee pain. Recalled injury had a significantly stronger association with subsequent knee pain (mild or severe) in the older (OR 2.39; 95% CI 1.45, 3.94) compared with the younger (OR 1.26; 95% CI 0.85, 1.88) group, whereas depression and obesity only had effects in the younger group (OR 1.66 compared with 1.17 and OR 1.40 compared with 1.12, respectively). This pattern was the same for the onset of severe pain, but in addition, females were significantly more likely than men to develop severe knee pain in the younger age group (OR 2.03, 95% CI 1.08, 3.78).


   Discussion
Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
Acknowledgements
 References
 
Our study adds to previous population-based studies by showing how risks for onset of knee pain in older people are different to those for its progression. This has implications for public health strategies and clinical practice in primary care.

We have expanded our earlier observations concerning the important influence of obesity on knee pain and highlighted that it is more strongly linked to progression and onset of severe knee pain than demographic, psychological or social characteristics. This finding contrasts with findings from studies of other regional pains, in which psychosocial factors tend to dominate prediction of chronicity [30]. It suggests that the biomechanical influence of body mass on the progression and severity of knee joint pain and its impact on daily life is as important, or more important, than general influences on chronicity of pain. There is some evidence from our study that psychosocial factors have a role (the non-significant but consistent associations between progression of knee pain and low educational attainment and socioeconomic status). However, the most marked predictors of progression of established pain other than obesity were general markers of chronicity (duration of the knee problem, extent of health care seeking), suggesting that, once the condition is established, the length of time the person has had the problem and the extent of health care seeking become selectively more powerful indicators of the likelihood that the problem will progress.

We did not find any strong independent predictors of the onset of knee pain in older people, which probably reflects the involvement of multiple causal pathways. The link between history of injury and onset of knee pain provides some evidence for biomechanical influences on pain onset, particularly in the oldest age group (>65 yrs) and this adds to the findings from previous studies and reviews about risk factors for OA [31]. In our study, previous knee injury was the strongest risk factor for the onset of any pain, but was less strongly linked with onset of severe pain and not at all with the likelihood of progression, which reflects findings related to incidence of radiographic knee OA [32] and progression of radiographic knee OA [13, 33].

Our findings add to previous observations from cross-sectional studies [34, 35] of a link between depression and knee pain. Although depression was not linked to progression of pain, there was an increased risk of onset of any knee pain in middle-aged adults who were depressed compared with those who were not depressed. Given evidence that treating depression can improve pain and disability in persons with knee OA [36], our observational study indicates that treatment of depression in adults has the potential also to prevent the onset of knee pain.

We have previously reported that pain outside the knee was associated in a cross-sectional survey with a higher likelihood of having knee pain, and considered that this might be a reflection of shared pathology (such as a generalized OA tendency) or of a chronic pain syndrome [37]. In the current study, the baseline presence of pain elsewhere than the knee was a risk factor for the subsequent onset of knee pain, including onset of severe knee pain, but not for progression of knee pain from mild to severe. This appears to contrast with findings about radiographic OA, such as Belo's systematic review [33], which reported that the strongest clinical marker for subsequent progression of radiographic OA is the presence of generalized OA, and suggests again that risk factors for onset and progression of pain may differ.

Dawson and colleagues [16] studied the factors associated with persistent hip or knee pain in adults aged ≥65 in the general population over a 1-yr period. The factors most strongly related to persistent hip or knee pain in this study were maximum Lequesne score, high baseline pain score and number of painful hip or knee joints at baseline. Our study has added to this by investigating longer term effects and by showing that pain in two or more regions (other than the knee) is linked to the onset of severe knee pain over a 3-yr period.

Obesity was linked to onset and progression of knee pain. The strongest link was with onset of severe pain with a weaker association for progression and this pattern reflects that found for a population-based study of radiographic knee OA in adults aged ≥55 in Rotterdam [38]. Maintenance of ideal body weight is recommended as a population strategy for prevention of musculoskeletal conditions [39]. We have previously discussed how integrating the message about the impact of obesity on musculoskeletal health with other health messages on obesity remains a public health challenge [15].

Apart from obesity, the strongest and most consistent predictors of progression were chronicity and use of other services, i.e. prior experience of the problem and its care. This suggests that older persons in the general population with mild-to-moderate knee pain which is destined to progress or deteriorate are receiving health care which is not effective enough to prevent deterioration. One reason may be that these are the people who utilize more health care because of comorbidity—our finding that prior consultation for multiple morbidities is linked to onset of severe pain or progression of pain would support this, as would Peters and colleagues’ [9] finding that deterioration of knee pain in adults in a 7-yr follow up study is linked with hypertension and other health problems. In addition, the likelihood that people will experience onset of severe knee pain in a 3-yr period was increased in our study if they had poor general physical function at baseline, indicating that prior comorbid disability also contributes to the probability of more rapidly progressive knee pain. This finding supports those of another UK prospective study of adults aged ≥75 [40] in which acquisition of joint pain over a 1-yr period was similarly linked to baseline disability levels.

It is possible that pain and disability levels at 3 yrs are related to previous arthroplasty. Linsell and colleagues [41] reported that hip or knee pain was more prevalent amongst older adults with past hip or knee replacement than amongst those without. Very few of our subjects, however (1% of those with non-severe knee pain at baseline), reported having had an operation in the past year at follow-up. However, older adults with knee pain are reluctant to consult their GP about knee problems and in this cohort over half of those with severe pain or physical functioning had not consulted a GP in the last 12 months about their knee problem [42]. We have previously highlighted potential unmet need for primary care in older adults with knee pain [1]. The fact that people are not accessing their GP would preclude any chance of referral to secondary care.

Peters’ study [9] suggested that socioeconomic factors play a more substantial role in determining the course of knee pain than we have identified. However, they were studying a younger population (≥35 yrs) and their findings may reflect the influence of mechanical stress on the knee from manual labour. Women <65 yrs were more likely in our sample to develop severe knee pain than men of the same age, but gender was not linked to progression. This is consistent with Belo's review which found that female gender was not related to deterioration of radiographic knee disease [33].

Strength and limitations
This study has compared the determinants of knee pain onset and progression in the general older population. We have concentrated on measures of potential determinants at a time point prior to the onset or progression of knee pain, and so avoided the difficulty of disentangling cause and effect in cross-sectional studies. Studying joint pain at a single site over time is complex for numerous reasons. First, although we asked specifically about the knee, there may be influences on severity from other weight-bearing sites or injuries. Of those who developed severe knee pain (onset or progression), 55% also reported pain in the hip, foot or ankle in the past 4 weeks at follow-up. The comparative figures were 23% for those in this study with no knee pain at follow-up and 37% in those with non-severe knee pain at follow-up. However, studies have shown that the majority of people who report knee pain do have radiographic evidence of knee OA [9, 43].

Second, our definition of knee pain means that pain may have moved from the left to the right knee, or vice versa, during the study follow-up period. This has allowed for a comprehensive assessment of pain and daily activities, whichever knee is affected. In fact, in those who progressed from non-severe to severe pain, only 2% had pain solely in a knee they reported free of pain at baseline.

Not all potential risks for either radiographic knee OA or knee pain (e.g. malalignment, occupation, physical activity) were measured. There is evidence from elsewhere, for example, that lack of physical activity increases the odds of functional decline [44] and that regular aerobic exercise protects against decline in physical functioning at the knee [45]. Our assessment of psychological factors was limited to measures of affect, whereas recent evidence suggests that broader psychological factors such as optimism and pessimism can affect physical functioning in older adults with knee pain [46]. In another longitudinal study of adults aged ≥75, the acquisition of ‘joint pain’ over a 1-yr period was linked to sadness [40] and incidence and persistence of knee pain in adults aged 25–64 has also been linked with low mood and somatizing tendency in a prospective cohort study in the UK [47].

Conclusion
No factor emerged as such a strong or consistent, potentially preventable cause of chronic knee pain as obesity, which should remain the major target for primary and secondary prevention of disabling knee pain. The potential for primary prevention of knee pain by tackling knee injuries and treating depression is supported by our data, although other factors are likely to determine whether the knee pain then becomes persistent or chronic. The presence of pain in other joints as a risk factor for future knee pain highlights the need for research into early intervention in people with a joint pain diathesis who present with such pain in primary care. Finally, the observation that previous experience of health care, duration of knee pain, comorbid illness and disability were stronger predictors than other factors of future progression of knee pain highlights a second important area for future research: the ineffectiveness of current health care in halting or reversing progression of knee pain at a population level.

Formula


   Acknowledgements
Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 Acknowledgements
References
 
We would like to thank the doctors and patients of the three health centres involved and also the administration team in Primary Care Musculoskeletal Research Centre who helped with the surveys.

Funding: The baseline survey was funded by The West Midlands New Blood Research Fellowship Committee (former West Midlands Regional Health Authority) and the Haywood Rheumatism Research and Development Foundation (HRRDF), North Staffordshire, UK. The follow-up survey was funded by the North Staffordshire Research and Development Consortium. All authors are independent of the funders.

Disclosure statement: The authors have declared no conflicts of interest.


   References
Top
 Abstract
 Introduction
 Patients and methods
 Results
 Discussion
 Acknowledgements
 References
 

  1. Jinks C, Jordan K, Ong BN, Croft P. A brief screening tool for knee pain in primary care (KNEST). 2. Results from a survey in the general population aged 50 and over. Rheumatology (2004) 43:55–61.[Abstract/Free Full Text]
  2. Jinks C, Jordan K, Croft P. Osteoarthritis as a public health problem: the impact of developing knee pain on physical function in adults living in the community: (KNEST 3). Rheumatology (2007) 46:877–81.[Abstract/Free Full Text]
  3. Department of Health. The musculoskeletal services framework. In: A joint responsibility: doing it differently (2006) London: HMSO.
  4. Department of Health. A new ambition for old age. In: Next steps implementing the National Service Framework for Older People (2006) London: HMSO.
  5. World Health Organization. Active ageing. In: A policy framework (2002) Geneva, Switzerland: World Health Organization.
  6. Andersen RE, Crespo CJ, Ling SM, Bathon JM, Bartlett SJ. Prevalence of significant knee pain among older Americans: results from the Third National Health and Nutrition Examination Survey. J Am Geriatr Soc (1999) 47:1435–8.[Web of Science][Medline]
  7. McAlindon TE, Cooper C, Kirwan JR, Dieppe PA. Knee pain and disability in the community. Br J Rheumatol (1992) 31:189–92.[Abstract/Free Full Text]
  8. O’Reilly SC, Muir KR, Doherty M. Knee pain and disability in the Nottingham community: association with poor health status and psychological distress. Br J Rheumatol (1998) 37:870–3.[Abstract/Free Full Text]
  9. Peters TJ, Sanders C, Dieppe P, Donovan J. Factors associated with change in pain and disability over time: a community-based prospective observational study of hip and knee osteoarthritis. Br J Gen Pract (2005) 55:205–11.[Web of Science][Medline]
  10. Arden N, Nevitt MC. Osteoarthritis: epidemiology. Best Pract Res Clin Rheumatol (2006) 20:3–25.[CrossRef][Medline]
  11. Hunter DJ, March L, Sambrook PN. Knee osteoarthritis: the influence of environmental factors. Clin Exp Rheumatology (2002) 20:93–100.
  12. Felson DT, Lawrence RC, Dieppe PA, et al. Osteoarthritis: new insights. Part 1: the disease and its risk factors. Ann Intern Med (2000) 133:635–46.[Abstract/Free Full Text]
  13. Cooper C, Snow S, McAlindon TE, et al. Risk factors for the incidence and progression of radiographic knee osteoarthritis. Arthritis Rheum (2000) 43:995–1000.[CrossRef][Web of Science][Medline]
  14. Doherty M. Risk factors for progression of knee osteoarthritis. Lancet (2001) 358:775–6.[CrossRef][Web of Science][Medline]
  15. Jinks C, Jordan K, Croft P. Disabling knee pain—another consequence of obesity: results from a prospective cohort study. BMC Pub Health (2006) 6:258.[CrossRef]
  16. Dawson J, Linsell L, Zondervan K, et al. Impact of persistent hip or knee pain on overall health status in elderly people: a longitudinal population study. Arthritis Rheum (2005) 53:368–74.[CrossRef][Web of Science][Medline]
  17. Bowling A, Bond M, Jenkinson C, Lamping DL. Short form 36 (SF36) Health Survey questionnaire: which normative data should be used? Comparisons between the norms provided by the Omnibus Survey in Britain, Health Survey for England and the Oxford Life Survey. J Pub Health Med (1999) 21:255–70.[Abstract/Free Full Text]
  18. Jinks C, Lewis M, Ong BN, Croft P. A brief screening tool for knee pain in primary care. 1. Validity and reliability. Rheumatology (2001) 40:528–36.[Abstract/Free Full Text]
  19. Bellamy N. WOMAC osteoarthritis index. In: A users guide (1996) London, ON: University of Western Ontario.
  20. Jinks C, Jordan K, Croft P. Measuring the population impact of knee pain and disability with the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC). Pain (2002) 100:55–64.[CrossRef][Web of Science][Medline]
  21. Ware JE, Snow K, Kosinski M, Gandek B. SF36 Health Survey. In: Manual & interpretation guide (1993) Boston: Health Institute, New England Medical Centre.
  22. Zigmond AS, Snaith RP. The Hospital Anxiety and Depression Scale. Acta Psychiatr Scand (1983) 67:361–70.[Web of Science][Medline]
  23. Herrmann C. International experiences with the Hospital Anxiety and Depression Scale – A review of validation data and clinical results. J Psychosom Res (1997) 42:17–40.[CrossRef][Web of Science][Medline]
  24. World Health Organization. Preventing and managing the global epidemic of obesity. In: Report of the World Health Organization consultation on obesity (1997) Geneva: World Health Organization.
  25. Lacey RJ, Lewis M, Jordan K, Jinks C, Sim J. Inter-rater reliability of scoring of pain drawings in self-reported health surveys. Spine (2005) 30:E455–8.[CrossRef][Web of Science][Medline]
  26. Office for National Statistics. National Statistics Socio-Economic Classification (NS-SEC 2002) (2002) London: Stationery Office.
  27. Porcheret M, Hughes R, Evans D, et al. Data quality of general practice electronic health records: the impact of a program of assessments, feedback, and training. J Am Med Inform Assoc (2004) 11:78–86.[Abstract/Free Full Text]
  28. Jordan K, Clarke AM, Symmons DP, et al. Measuring disease prevalence: a comparison of musculoskeletal disease using four general practice consultation databases. Br J Gen Pract (2007) 57:7–14.[Web of Science][Medline]
  29. Jordan K, Jinks C, Croft P. A prospective study of the consulting behaviour of older people with knee pain. Br J Gen Pract (2006) 56:269–76.[Web of Science][Medline]
  30. Carragee EJ, Alamin TF, Miller JL, Carragee JM. Discographic, MRI and psychosocial determinants of low back pain disability and remission: a prospective study in subjects with benign persistent back pain. Spine J (2005) 5:24–35.[CrossRef][Medline]
  31. Sharma L, Kappoor D, Issa S. Epidemiology of osteoarthritis: an update. Curr Opin Rheumatol (2006) 18:147–56.[Web of Science][Medline]
  32. Gelber AC, Hochberg MC, Mead LA, Wang NY, Wigley FM, Klag MJ. Joint injury in young adults and risk for subsequent knee and hip osteoarthritis. Ann Intern Med (2000) 133:321–8.[Abstract/Free Full Text]
  33. Belo JN, Berger MY, Reijman M, et al. Prognostic factors of progression of osteoarthritis of the knee: a systematic review of observational studies. Arthritis Rheum (2007) 57:13–26.[CrossRef][Web of Science][Medline]
  34. O’Reilly SC, Muir KR, Doherty M. Knee pain and disability in the Nottingham community: association with poor health status and psychological distress. Br J Rheumatol (1998) 37:870–3.[Abstract/Free Full Text]
  35. Creamer P, Lethbridge-Cejku M, Costa P, Tobin JD, Herbst JH, Hochberg MC. The relationship of anxiety and depression with self-reported knee pain in the community: data from the Baltimore longitudinal study of aging. Arthritis Care Res (1999) 12:3–7.[CrossRef][Web of Science][Medline]
  36. Lin EH, Katon W, Von Korff M, et al. Effect of improving depression care on pain and functional outcomes among older adults with arthritis: a randomized controlled trial. JAMA (2003) 290:2428–9.[Abstract/Free Full Text]
  37. Croft P, Jordan K, Jinks C. ‘Pain elsewhere’ and the impact of knee pain in older people. Arthritis Rheum (2005) 52:2350–4.[CrossRef][Web of Science][Medline]
  38. Reijman M, Pols HA, Bergink AP, et al. Body mass index associated with onset and progression of osteoarthritis of the knee but not of the hip: the Rotterdam Study. Ann Rheum Dis (2007) 66:158–62.[Abstract/Free Full Text]
  39. Woolf AD, Akesson K. Understanding the burden of musculoskeletal conditions. The burden is huge and not reflected in national health priorities. Br Med J (2001) 322:1079–80.[Free Full Text]
  40. Donald IP, Foy C. A longitudinal study of joint pain in older people. Rheum (2004) 43:1256–60.[CrossRef]
  41. Linsell L, Dawson J, Zondervan K, et al. Pain and overall health status in older people with hip and knee replacement: a population perspective. J Pub Health (2007) 28:267–73.
  42. Jinks C, Ong BN, Richardson JC. A mixed methods study to investigate needs assessment for knee pain and disability. Population and individual perspectives. BMC Musculoskel Dis (2007) 8:59.[CrossRef]
  43. Duncan R, Peat G, Thomas E, Hay E, McCall I, Croft P. Symptoms and radiographic osteoarthritis: not as discordant as they are made out to be? Ann Rheum Dis (2007) 66:86–91.[Abstract/Free Full Text]
  44. Dunlop D, Semanik P, Song J, Manheim L, Shih V, Chang R. Risk factors for functional decline in older adults with arthritis. Arthritis Rheum (2005) 52:1274–82.[CrossRef][Web of Science][Medline]
  45. Sharma L, Cahue S, Song J, Hayes K, Pai YC, Dunlop D. Physical functioning over three years in knee osteoarthritis: role of psychosocial, local mechanical, and neuromuscular factors. Arthritis Rheum (2003) 48:3359–70.[CrossRef][Web of Science][Medline]
  46. Brenes GA, Rapp SR, Rejeski WJ, Miller ME. Do optimism and pessimism predict physical functioning? J Behav Med (2002) 25:219–31.[CrossRef][Web of Science][Medline]
  47. Palmer KT, Reading I, Calnan M, Linaker C, Coggon D. Does knee pain in the community behave like a regional pain syndrome? Prospective cohort study of incidence and persistence. Ann Rheum Dis (2007) 66:1190–4.[Abstract/Free Full Text]
Submitted 18 September 2007; revised version accepted 17 December 2007.
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