A prognostic approach to defining chronic pain: replication in a UK primary care low back pain population

A novel prognostic approach to defining chronic pain was developed in a US primary care low back pain population, using a combination of information about pain history, current status and likely prognosis. We tested whether this method was generalizable to a UK population. A prospective cohort of 426 patients who consulted with back pain at one of five UK general practices, and who returned follow-up information 1-year later were included. A baseline risk score was calculated based on pain severity and prognostic measures (depression, diffuse pain, pain duration), and cut-points from the US study applied for the risk of future clinically significant back pain, as defined by Chronic Pain Grades 2-4. New cut-points were also derived for the UK population using identical methods. The cut-points for probable and possible chronic pain developed in the US population (80% and 50% probability of future clinically significant back pain, respectively) were appropriate for the UK population, but the cut-point for classifying people at low risk (20% probability) was not replicated in the UK sample. The newly derived cut-points in the UK sample were similar; they remained the same for probable chronic pain, were slightly increased for possible chronic pain, and slightly reduced for those at intermediate or low risk. This method for defining chronic pain prospectively, using risk thresholds for future clinically significant pain, appears to be generalizable to a UK back pain population, particularly for identifying probable chronic pain, and may be generalizable to other primary care low back pain populations.     

A prognostic approach to defining chronic pain: application to knee pain in older adults

A prognostic approach to defining chronic pain has been proposed as an alternative to traditional definitions based on retrospective duration of pain. While this new approach performs well in low back pain (LBP), headache and orofacial pain, it is not known whether it translates to regional pain syndromes with an underlying pathological component, such as osteoarthritis (OA). We investigated the performance of this approach in a population-based cohort of older adults reporting knee pain, with a spectrum of radiographic knee OA. 676 adults (50 years+) attended a research clinic and were followed up at 18 months and 3 years. Risk scores were calculated using pain intensity, pain duration, pain-related activity, number of pain sites and depressive symptoms, measured at baseline and at 18 months. These scores were used to determine the probability of future clinically significant knee pain, defined as Chronic Pain Grade II-IV, at 18 months and at 3 years using logistic regression. Cut-points on the risk score were applied to determine groups at intermediate (probability >or=0.2), possible (>or=0.5) and probable (>or=0.8) risk of clinically significant knee pain. Discriminative ability of the risk scores, determined by area under the ROC curve, was high (0.78-0.82), varied little by radiographic severity and was superior to pain duration alone. The derived cut-points suggested a lower threshold for each of the risk groups than the previous LBP work. This prognostic approach to defining chronic pain appears to translate well to knee pain. Different cut-points for defining risk groups may be needed for different pain syndromes.     

Psychophysical Tests as Predictors of Back Pain Chronicity in Primary Care

If persons at risk of developing chronic pain could be identified early in a pain episode, treatment could be tailored on the basis of risk. Responses to psychophysical tests differ in persons with chronic pain vs pain-free controls and thus appear promising as indicators of susceptibility to chronic pain. In a cohort of 157 patients making their first primary care visit during a back pain episode, we explored the relationships of psychophysical test responses (pressure pain thresholds at low back and thenar sites, cold pressor pain ratings, conditioned pain modulation, and mechanical temporal summation) to baseline measures of pain and psychological distress and assessed whether test responses predicted clinically significant back pain 4 months later. Examiner-standardized pressure pain thresholds were significantly (P < .05) correlated with baseline back pain severity and diffuseness of bodily pain (Pearson correlations = −.21 to −.35). Lower baseline pressure pain thresholds significantly predicted back pain at 4 months (odds ratio [95% confidence interval]: low back, .66 [.44, .96]; thenar, .62 [.40, .92]); however, after controlling for participant age and sex, these associations were no longer significant. Cold pressor pain, conditioned pain modulation, and mechanical temporal summation were not significant predictors of 4-month back pain in either model.     

Cross-validation of the Back Pain Classification Scale with chronic, intractable pain patients

The current study investigated the utility of the Back Pain Classification Scale with chronic, intractable low back pain and headache patients. Subjects consisted of 50 chronic low back pain and 50 chronic headache patients referred to a university based Pain Center for evaluation. Data indicated that subjects were a representative sample of severely intractable chronic pain patients typically referred for Pain Center evaluation and treatment. Each was administered the Back Pain Classification Scale as part of a thorough physical and psychological/behavioral evaluation. All subjects were classified by blind review of medical records into one of two categories: (1) presence of psychopathologically based pain complaint with little or no pathophysiological findings and (2) presence of pathophysiologically based pain complaints with little or no psychopathological findings. Subjects were also independently classified from blind review of their scores on the Back Pain Classification Scale into one of these two categories. Findings revealed that the Back Pain Classification Scale accurately predicted the actual classification of 80% of the low back pain patients (i.e., 30% above baseline prediction rate) and only 60% of the chronic headache patients (i.e., only equal to the baseline prediction rate). Furthermore, the scale was found to be most accurate in predicting low back pain patients with primary psychopathologically based pain. It was concluded that the Back Pain Classification Scale was an empirically valid instrument to use with chronic low back pain patients, but not with chronic headache patients. This lack of utility with chronic headache patients was also viewed as support for the construct validity of the scale. Wider use of the scale with chronic low back pain patients was suggested.     

Chronischer unspezifischer Rückenschmerz

Chronic low back pain represents an important issue not only for the patients but also for society. Apreventive diagnosis could open the possibility to predict the individual probability of developing chronic low back pain in pain-free persons or persons with sub-acute low back pain if no further preventive interventions would be started. Every year about 20% of adults will suffer from back pain and 70-80% of society will suffer from back pain during their lives. In most cases back pain is alleviated within the first 6 weeks without any medical intervention. Only a few cases are progredient and chronic with immense costs for society and health care systems. It is necessary to find out which individuals will probably suffer from chronic back pain in the future. The diagnostic outcome of the classification should help to answer the question which subgroups of patients with chronic low back pain will especially benefit from exercise therapy or cognitive behavior therapy?     

Transition from acute to chronic pain and disability: a model including cognitive, affective, and trauma factors

This study evaluated a theoretically and empirically based model of the progression of acute neck and back pain to chronic pain and disability, developed from the literature in chronic pain, cognition, and stress and trauma. Clinical information and standardized psychosocial measures of cumulative traumatic events exposure (TLEQ), depressed mood (CES-D), pain (DDS), physical disability (PDI), and pain beliefs (PBPI) were collected at baseline from 84 acute back pain patients followed at an Acute Back Clinic over 3 months. Path analysis was used for the longitudinal prediction of perceived pain and disability. The predictive model accounted for 26% of the variance in persistent pain intensity and 58% of the variance in perceived physical disability at 3 months. Greater exposure to past traumatic life events and depressed mood were most predictive of chronic pain; depressed mood and negative pain beliefs were most predictive of chronic disability. More cumulative traumatic life events, higher levels of depression in the early stages of a new pain episode, and early beliefs that pain may be permanent significantly contribute to increased severity of subsequent pain and disability. Replication in a larger sample is desirable to confirm these paths. Early detection of elevated depressive symptoms and high trauma exposure may identify individuals at greater risk for developing chronic pain syndromes who may benefit from early multidisciplinary intervention.     

Moderate to Severe Chronic Pain in Later Life: Risk and Resilience Factors for Recovery

Despite extensive research on the development and risk factors of chronic pain, the process of recovery from chronic pain in later life has been rarely studied. We estimated the recovery rate of moderate to severe chronic pain (chronic pain of moderate or severe severity or interfering with usual activities) among older adults and investigated predictors of recovery. Leveraging the longitudinal Health and Retirement Study 2006–2016 data (6 waves), we estimated the biennial national attrition-adjusted recovery rate of moderate to severe chronic pain among 6,132 US adults aged 65–75 at baseline. Generalized estimating equation Poisson models examined pain-related, sociodemographic, psychosocial and health-related factors in relation to recovery within any 2-year interval using longitudinal lagged design. Between 2006–2016, the prevalence of moderate to severe chronic pain increased from 28% to 33% with the incidence increasing from 14% to 18% and the recovery rate approximately 30%. Previous chronic pain duration, age, chronic diseases and a personality trait (agreeableness) were associated with a lower probability of recovery. Greater financial wealth and physical activity, better sleep quality and self-reported health were associated with a greater probability of recovery. Interventions that improve physical activity and sleep quality may be important avenues for reducing chronic pain burden among older adults.PerspectiveOur longitudinal findings suggested that recovery from moderate to severe chronic pain is common in later life and we further identified several key factors associated with this recovery process. Future research should consider the potential of interventions that improve physical activity and sleep quality to enhance recovery among older adults.     

Differential Predictors of Pain Severity Over 12 Months Following Noncatastrophic Injury Sustained in a Road Traffic Crash

There is paucity of prospective studies that have examined rates and prognostic indicators of pain severity after a road traffic crash injury. This cohort study involved 1,854 participants aged ≥17 years with a noncatastrophic injury. Primary analyses of pain severity involved 1604 individuals who reported any pain since the injury at baseline Of these, 1,188 and 972 participants were reexamined at the 6- and 12-month follow-up, respectively. The mean pain severity (primary study outcome) was assessed using a numeric rating scale (NRS), and a range of possible pain predictors were assessed. A mean pain NRS score of 4.9 was observed at baseline, and the mean NRS score was 2.1 at the 12-month follow-up. At the 6- and 12-month follow-up, 21% and 17.5% reported clinically significant pain (NRS score of ≥5), respectively. After multivariable adjustment, key predictors of pain severity ratings over the 12 months included the following, which were measured at baseline: age, sex, education, claim compensation, spine/back injury, being a bicyclist, physical well-being, pain-related catastrophizing, pain-related disability, and trauma-related and general psychological distress. Clinically significant pain was experienced by just >1 in 6 participants 12 months after injury. Several independent contributors to chronic pain identified in this study are modifiable, reinforcing their inclusion as targets in pain management programs.PerspectiveThis cohort study involving participants who sustained a noncatastrophic injury in a road traffic crash established the predictors of pain severity over 12 months. Study findings reiterate and reinforce the importance of being cognizant of a wide spectrum of biopsychosocial predictors both in the management and rehabilitation of injured persons.     

Chronic back pain: more than pain in the back. Findings of a regional survey among insurees of a workers pension insurance fund

BACKGROUND: Surveys with a main focus on back pain tend to isolate the complaint from possibly concomitant pains, other symptoms and disorders. Severe chronic back pain is assumed here to imply more than pain in the back. PARTICIPANTS AND METHODS: We report results from a two stage survey conducted in 1998 - 2000. The initial postal questionnaire addressed all 10,000 actively employed blue collar workers from a regional pension fund (Landesversicherungsanstalt Schleswig-Holstein) aged 40 - 54 and residing in or around Luebeck/Germany (68 % males). Subjects reporting severe and disabling back pain were invited to a socio-medical examination. The response and participation rates were 58 % and 65 % respectively. Non-response and non-participation seem to result in minor though opposite, effects. RESULTS: The prevalence of current back pain (back pain of any severity within the past 7 days) is high (68 %; including 16 % with severe, disabling back pain) despite the preponderance of males and a probable healthy worker effect. 82 % of subjects participating in the second round reported recurrent or persisting back pain on the day of examination, in the majority with a chronic fluctuating and overall deteriorating course pattern. 18 % reported no current back pain and hence gave prospective (and additionally retrospective) evidence of an episodic-intermittent course of the disorder. The former group showed significantly more pains, bodily complaints, dysfunctional cognitions, emotional distress and concomitant disorders. 35 % of them indicated back pain as their dominant health problem; 49 % identified back pain and another disorder as dominant, and 16 % reported other prominent health problems. More than 70 % of "other" disorders originated from the musculoskeletal system often involving the extremities. SUMMARY AND CONCLUSION: Back pain is very common among blue collar workers. Severe disabling back pain is usually associated with numerous other pains, bodily complaints, disorders, and indicators of psychological distress ("amplified back pain"). However, even amplified back pain is not always the sole or dominant health problem. Assessing the degree of "amplification" seems helpful in splitting a previously homogeneous group of severely affected back pain sufferers-with possible prognostic and therapeutic consequences.     

Repeat assessment improves the prediction of prognosis in patients with low back pain in primary care

Low back pain is considered to fluctuate over time, and related prognostic factors may behave similarly, therefore classification of prognosis may be affected by timing of assessment. We aimed to investigate the implications of timing of assessment of prognosis in low back pain. In a prospective cohort of primary care low back pain consulters aged 30-59 years, 359 returned questionnaires at baseline, one-month and one-year. The stability of selected prognostic indicators between baseline and one-month later was assessed, and relative risks for their association with outcome (individually and in combination) were calculated. Reported absence of most outcome indicators was stable between baseline and one-month. However, among people reporting presence of indicators at baseline, only around half still reported them a month later. There were no important differences between the prognostic strength of indicators measured at baseline or one-month. People reporting presence of indicators at either point had significantly higher risk of poor outcome than people not reporting the indicator at all. Presence of the indicators at both time points was associated with even higher risk; people with persistent high pain intensity had 15 times the risk of a poor outcome (relative risk 15.1; 95% confidence interval 6.7-33.8) compared with people not reporting high pain at either point. Combining information on prognostic indicators from two time points provides better classification of low back pain patients' eventual outcome than a single measurement alone. This increased accuracy in predicting prognosis is relevant to both clinical and research practice.     

The impact of implantable cardiac defibrillators for primary prophylaxis in the community: baseline risk and clinically meaningful benefits

OBJECTIVE: To estimate the baseline risk of arrhythmic death required for prophylactic implantable cardiac defibrillators (ICDs) to result in clinically meaningful survival benefits in the population. BACKGROUND: While proven efficacious, the absolute survival impact of ICDs for the primary prevention of sudden cardiac death among patients with left ventricular (LV) dysfunction is highly dependent upon patient's baseline risk of arrhythmic death. METHODS: Using echocardiographic data from a random sample of patients identified from community echocardiographic laboratories, patients with moderate or severe LV dysfunction (ejection fraction < 35%) were linked to administrative databases to characterize baseline mortality risk (median follow-up duration of 4.85 years). Relative efficacy was ascertained from meta-analysis and clinical trial data. The baseline annual risk of arrhythmic death required for prophylactic ICDs to result in clinically meaningful survival benefits in the population was estimated at different ranges of relative efficacy and numbers needed to treat (NNTs) thresholds. RESULTS: LV dysfunction was a significant independent predictor of adverse outcomes. In total, 35.4% of the patients with moderate to severe LV dysfunction died during the follow-up period. Assuming a base-case relative efficacy of 66%, we estimated that the baseline risk for arrhythmic death required to exert a clinically meaningful NNT threshold of 50 in order to prevent one death (from any cause) was 3% per year or higher. CONCLUSIONS: The survival impact and cost-effectiveness of prophylactic ICDs in the population will depend upon the ability to risk-stratify and identify patients whose baseline risk for sudden cardiac death exceed 3% per year.     

Are prognostic indicators for poor outcome different for acute and chronic low back pain consulters in primary care?

Few studies have investigated whether prognostic indicators, which contribute to the transition from acute to chronic low back pain (LBP), are also those which contribute to continuing persistence of chronic LBP. We compared the contribution of physical, psychological and social indicators to predicting disability after one year between consulters with LBP of less than 3 months duration and more than 3 months duration. Data from two large prospective cohort studies of consecutive patients consulting with LBP in general practices were merged, providing complete data for 258 cases with acute/subacute LBP and 668 cases with chronic LBP at 12 months follow-up. There were significant differences between the two LBP groups in baseline characteristics and clinical course of disability, assessed by Roland Morris Disability Questionnaire, during the year of follow-up. Adjusted associations between potential prognostic indicators and disability at 12 months were carried out in the two LBP subgroups. The final multivariable regression models showed that being non-employed, having widespread pain, a high level of Chronic Pain Grade, and catastrophising were the strongest prognostic indicators for disability at 12 months in both LBP groups. Fear of pain was significantly associated with disability in chronic LBP. Importantly, beyond baseline disability, the effect size of the other prognostic indicators for poor outcome was rather low. These findings must continue to challenge researchers to identify useful early predictors of outcome in persons with disabling back pain, as screening and targeted treatment approaches are dependent upon prognostic indicators with clinical significance.     

Course and prognosis of older back pain patients in general practice: A prospective cohort study

The aim of the current study was to determine the course of back pain in older patients and identify prognostic factors for non-recovery at 3 months’ follow-up. We conducted a prospective cohort study (the BACE study) of patients aged >55 years visiting a general practitioner (GP) with a new episode of back pain in the Netherlands. The course of back pain was described in terms of self-perceived recovery, pain severity, disability, pain medication, and GP visits at 6 weeks’ and 3 months’ follow-up. Prognostic factors for non-recovery at 3 months’ follow-up were derived from the baseline questionnaire and physical examination. Variables with a prognostic value were identified with multivariable logistic regression analysis (method backward), and an area under the receiver operating curve (AUC) was calculated for the prognostic model. A total of 675 back pain patients (mean age 66.4 (SD 7.6) years) participated in the BACE cohort study. At 6 weeks’ follow-up 64% of the patients reported non-recovery from back pain. At 3 months’ follow-up 61% still reported non-recovery, but only 26% of these patients had revisited the GP. Longer duration of the back pain, severity of back pain, history of back pain, absence of radiating pain in the leg below the knee, number of comorbidities, patients’ expectation of non-recovery, and a longer duration of the timed ‘Up and Go’ test were significantly associated with non-recovery in a multiple regression model (AUC 0.79). This information can help GPs identify older back pain patients at risk for non-recovery.     

Ranking of parameters of pain hypersensitivity according to their discriminative ability in chronic low back pain

Low back pain is associated with plasticity changes and central hypersensitivity in a subset of patients. We performed a case-control study to explore the discriminative ability of different quantitative sensory tests in distinguishing between 40 cases with chronic low back pain and 300 pain-free controls, and to rank these tests according to the extent of their association with chronic pain. Gender, age, height, weight, body mass index, and psychological measures were recorded as potential confounders. We used 26 quantitative sensory tests, including different modalities of pressure, heat, cold, and electrical stimulation. As measures of discrimination, we estimated receiver operating characteristics (ROC) and likelihood ratios. Six tests seemed useful (in order of their discriminative ability): (1) pressure pain detection threshold at the site of most severe pain (fitted area under the ROC, 0.87), (2) single electrical stimulation pain detection threshold (0.87), (3) single electrical stimulation reflex threshold (0.83), (4) pressure pain tolerance threshold at the site of most severe pain (0.81), (5) pressure pain detection threshold at suprascapular region (0.80), and (6) temporal summation pain threshold (0.80). Pressure and electrical pain modalities seemed most promising and may be used for diagnosis of pain hypersensitivity and potentially for identifying individuals at risk of developing chronic low back pain over time.     

A practice-based study of patients with acute and chronic low back pain attending primary care and chiropractic physicians: two-week to 48-month follow-up

OBJECTIVE: This study reports pain and disability outcomes up to 4 years for chiropractic and medical patients with low back pain (LBP) and assesses the influence of doctor type and pain duration on clinical outcomes. DESIGN: Prospective, longitudinal, nonrandomized, practice-based, observational study. SETTING: Fifty-one chiropractic and 14 general practice community clinics. SUBJECTS: A total of 2870 acute and chronic ambulatory patients with LBP of mechanical origin. METHODS: Sixty chiropractic (DC) and 111 general practice (MD) physicians participated. Primary outcomes were pain, using a 100-point visual analogue scale (VAS), and functional disability, using the Revised Oswestry Disability Questionnaire. These were measured at baseline and 8 time points. Regression analysis compared acute and chronic DC and MD patients after correcting for baseline differences in the 4 cohorts. RESULTS: Most improvement was seen by 3 months and sustained for 1 year; exacerbation was seen thereafter. Acute patients demonstrated greater relief at all time points. A clinically important advantage for chiropractic patients was seen in chronic patients in the short-term (>10 VAS points), and both acute and chronic chiropractic patients experienced somewhat greater relief up to 1 year (P<.000). The advantage for DC care was prominent for chronic patients with leg pain below the knee (P<.001). More than 50% of chronic patients had over 50 days of pain in the third year. CONCLUSION: Study findings were consistent with systematic reviews of the efficacy of spinal manipulation for pain and disability in acute and chronic LBP. Patient choice and interdisciplinary referral should be prime considerations by physicians, policymakers, and third-party payers in identifying health services for patients with LBP.     

Psychosocial Predictors of Acute and Chronic Pain in Adolescents Undergoing Major Musculoskeletal Surgery

Acute and chronic pain delay recovery and impair outcomes after major pediatric surgery. Understanding unique risk factors for acute and chronic pain is critical to developing effective treatments for youth at risk. We aimed to identify adolescent and family psychosocial predictors of acute and chronic postsurgical pain after major surgery in adolescents. Participants included 119 youth age 10 to 18 years (M_age = 14.9; 78.2% white) undergoing major musculoskeletal surgery and their parents. Participants completed presurgery baseline questionnaires, with youth reporting on baseline pain, anxiety, depression, insomnia and sleep quality, and parents reporting on parental catastrophizing and family functioning. At baseline, 2-week, and 4-month postsurgery, youth completed 7 days of daily pain diaries and reported on health-related quality of life. Sequential logistic regression models examined presurgery predictors of acute and chronic postsurgical pain, defined as significant pain with impairment in health-related quality of life. Acute pain was experienced by 27.2% of youth at 2 weeks, while 19.8% of youth met criteria for chronic pain at 4 months. Baseline pain predicted acute pain (odds ratio [OR] = 1.96; 95% confidence interval [CI] = 1.32–2.90), while depressive symptoms (OR = 1.22; 95%CI = 1.01–1.47), and sleep quality (OR = 0.26; 95%CI = 0.08–0.83) predicted chronic pain. Tailored interventions need to be developed and incorporated into perioperative care to address risk factors for acute and chronic pain.PerspectiveLongitudinal results demonstrate adolescents’ presurgery pain severity predicts acute postsurgical pain, while depressive symptoms and poor sleep quality predict chronic postsurgical pain. Tailored interventions should address separate risk factors for acute and chronic pain after adolescent surgery.     

Site-specific visual feedback reduces pain perception

One of the most common forms of chronic pain is back pain. Until now, nothing has been known about the influence of visualizing one’s own back on pain perception at this site. We tested 18 patients with chronic back pain and 18 healthy controls, by implementing online video feedback of the back during painful pressure and subcutaneous electrical stimuli over the trapezius muscle. Pain threshold and pain tolerance were assessed. Pressure pain stimulation intensity was set to 50% above the pain threshold. Subcutaneous stimulation intensity was set to 70% above the pain threshold. Subjects had to rate pain intensity and unpleasantness after each stimulation block on an 11-point numerical rating scale. Visual feedback of the back reduced perceived pain intensity compared to feedback of the hand in both patients and controls. These findings suggest novel intervention modes for chronic back pain based on visualization of body parts by augmented reality applications.     

Risk factors for neck pain: a longitudinal study in the general population

The objective of the study was to examine the 1-year cumulative incidence of episodic neck pain and to explore its associations with individual risk factors, including a history of previous neck injury. A baseline cross-sectional survey of an adult general population sample made up of all 7669 adults aged 18-75 years, registered with two family practices in South Manchester, United Kingdom, identified the study population of adults with no current neck pain. This study population was surveyed again 12 months later to identify all those who had experienced neck pain during the follow-up period. At follow-up, cumulative 1-year episode incidence of neck pain was estimated at 17.9% (95% confidence interval 16.0-19.7%). Incidence was independent of age, but was more common in women. A history of previous neck injury at baseline was a significant risk factor for subsequent neck pain in the follow-up year (risk ratio 1.7, 95% confidence interval 1.2-2.5), independent of gender and psychological status. Other independent baseline risk factors for subsequent neck pain included number of children, poor self-assessed health, poor psychological status and a past history of low back pain. We have carried out a prospective study in a general population sample and demonstrated that established risk factors for chronic pain predict future episodes of neck pain, and shown that in addition a history of neck injury is an independent and distinct risk factor. This finding may have major public health and medicolegal implications.     

Grading the severity of chronic pain.

This research develops and evaluates a simple method of grading the severity of chronic pain for use in general population surveys and studies of primary care pain patients. Measures of pain intensity, disability, persistence and recency of onset were tested for their ability to grade chronic pain severity in a longitudinal study of primary care back pain (n = 1213), headache (n = 779) and temporomandibular disorder pain (n = 397) patients. A Guttman scale analysis showed that pain intensity and disability measures formed a reliable hierarchical scale. Pain intensity measures appeared to scale the lower range of global severity while disability measures appeared to scale the upper range of global severity. Recency of onset and days in pain in the prior 6 months did not scale with pain intensity or disability. Using simple scoring rules, pain severity was graded into 4 hierarchical classes: Grade I, low disability--low intensity; Grade II, low disability--high intensity; Grade III, high disability--moderately limiting; and Grade IV, high disability--severely limiting. For each pain site, Chronic Pain Grade measured at baseline showed a highly statistically significant and monotonically increasing relationship with unemployment rate, pain-related functional limitations, depression, fair to poor self-rated health, frequent use of opioid analgesics, and frequent pain-related doctor visits both at baseline and at 1-year follow-up. Days in Pain was related to these variables, but not as strongly as Chronic Pain Grade. Recent onset cases (first onset within the prior 3 months) did not show differences in psychological and behavioral dysfunction when compared to persons with less recent onset. Using longitudinal data from a population-based study (n = 803), Chronic Pain Grade at baseline predicted the presence of pain in the prior 2 weeks. Chronic Pain Grade and pain-related functional limitations at 3-year follow-up. Grading chronic pain as a function of pain intensity and pain-related disability may be useful when a brief ordinal measure of global pain severity is required. Pain persistence, measured by days in pain in a fixed time period, provides useful additional information.