<\/p>\n
One thing clinicians and investigators can agree upon is that finding valid, precise, reliable, and accurate measures of chronic pain in animals is a very tall order indeed. However, the effort is important\u2014if we are to effectively manage patients with chronic pain, we have to be able to assess it, which also allows us to determine whether our interventions are therapeutic.<\/p>\n
Chronic pain significantly impacts quality of life in animals, as it does in humans. In addition to the discomfort itself, there is diminished mobility and ability to perform normal activities of daily living. In humans, chronic pain is associated with cognitive deficits (learning, memory, etc) and increasingly understood to coexist with clinical depression.1,2<\/sup> Other, nonpainful conditions can influence chronic pain assessment, including neurologic and metabolic disease.<\/p>\n There are 5 prospective methods to assess and score chronic pain:<\/p>\n Unfortunately, veterinarians have found chronic pain scoring based on physical examination disappointing. Reasons include:<\/p>\n Currently there are no biomarkers (biochemical or physiologic parameters) that reliably correlate to chronic pain, although this is an area under active investigation. Physiologic biomarkers, such as blood pressure, heart rate, and cortisol levels, have very low specificity because circumstances other than pain (eg, fear, anxiety, stress) also affect these markers.<\/p>\n Objective measurements, such as force plate analysis or activity monitors, when properly utilized, are valid in the research setting but, at this time, have not translated into clinical practice. As technology advances, these may be promising clinical modalities in the near future.<\/p>\n Owner assessment of ADL is currently the most scientifically and clinically useful chronic pain scoring tool.<\/p>\n The most common chronic pain condition encountered in dogs and cats is osteoarthritis (OA); other conditions that can cause chronic pain include intervertebral disk disease, cancer, and nonmalignant neuropathies\/myopathies.<\/p>\n The clinical observations owners generally make are related to behavior changes in their pets. Clients most often notice the growing absence of behaviors once considered routine (diminished abilities or disability); less often they notice onset of new behaviors (eg, lameness, vocalization).<\/p>\n Several challenges exist when relying on owner observations to evaluate chronic pain in pets:<\/p>\n Due to the limitations and challenges noted above, observation-based owner questionnaires and multifactorial clinical measurement instruments (CMIs) have been developed and validated in animals and humans, with the latter often inspiring the former.<\/p>\n Before questionnaires and CMIs are considered ready for clinical use, an extensive development process evaluates several levels and layers of validity. To learn more about this validation process, visit the North Carolina State University Comparative Pain Research Laboratory’s webpage on Clinical Metrology Instruments at cvm.ncsu.edu\/docs\/cprl\/cmi.html.<\/p>\n Several CMIs have been validated in dogs and others are under development in cats.<\/p>\n The Helsinki Chronic Pain Index (HCPI) for dogs with OA was first described in 20034 and then validated in 2009.5<\/sup><\/p>\n For the HCPI, 11 items are scored 0 to 4, divided between a:<\/p>\n This system has also been used to assess response to nutritional therapy for OA.6,7<\/sup> In one study, HCPI correlated well with improvements of objective gait assessments in the study group; however, improvement in HCPI was also seen in the placebo group while objective measurements worsened.8<\/sup> The paradox of these results speaks to the inherent challenges and limitations of not only CMIs but also objective measurements.<\/p>\n The Canine Brief Pain Index (CBPI) was adapted from a human Brief Pain Index and validated for canine OA in 20079<\/sup> and osteosarcoma in 2009.10<\/sup><\/p>\n The CBPI asks owners to assign a score to 11 domains.<\/p>\n Cincinnati Orthopedic Disability Index<\/span><\/strong> Instead of relying on the same standard questions for each patient, the CODI asks owners what difficulties they believe their dogs are exhibiting.<\/p>\n The CODI has been used to assess an adjunctive pain modifying drug15<\/sup> and, recently in a trial investigating a canine OA food, it correlated well with objective measurements (gait analyses) and outperformed CBPI and the Health-Related Quality of Life (HRQL) CMI in evaluating response to therapy.16<\/sup> Health-Related Quality of Life (Glasgow University Health-Related Dog Behaviour Questionnaire)<\/p>\n The Health-Related Quality of Life (HRQL) was developed specifically for veterinary patients versus being derived from an existing CMI for humans.<\/p>\n The original OA HRQL was recently (2013) refined and reduced to include only 46 items that fall under 4 domains:21<\/sup><\/p>\n The Liverpool Osteoarthritis in Dogs (LOAD) CMI was first validated to evaluate canine elbow arthritis (2009)22<\/sup>; however, it also compares favorably with HRQL and CBPI and correlates (albeit weakly) with objective measurements (gait analyses).23<\/sup> LOAD asks owners to assess their dogs’ mobility in 13 areas (5 General domains and 8 At Exercise domains) on a 0 to 4 Simple Descriptive Scale.<\/p>\n In the near future, practitioners can expect to see one or more of these chronic pain scoring tools adapted for use in the clinical setting. With widespread use, our ability to follow patients with chronic pain, and adjust their management accordingly, can be expected to improve significantly.<\/p>\n Feline OA appears to have a different etiopathophysiology than OA in dogs, and fundamental peculiarities of feline behavior appear to create a strong placebo effect in pain studies.<\/p>\n Development of a valid CMI for this species is an area of active investigation:<\/p>\n ADL = activities of daily living; CBPI = Canine Brief Pain Index; CMI = clinical measurement instrument; CODI = Cincinnati Orthopedic Disability Index; CSOM = client-specific outcome measures; HCPI = Helsinki Chronic Pain Index; HRQL = Health-Related Quality of Life; IVAPM = International Veterinary Academy of Pain Management; LOAD = Liverpool Osteoarthritis in Dogs; OA = osteoarthritis<\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" One thing clinicians and investigators can agree upon is that finding valid, precise, reliable, and accurate measures of chronic pain in animals is a very tall order indeed.<\/p>\n","protected":false},"author":1,"featured_media":2776,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"iawp_total_views":2748,"footnotes":""},"categories":[371],"tags":[13],"class_list":["post-1260","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-november-december-2013","tag-peer-reviewed","column-features","clinical_topics-pain_management"],"acf":{"hide_sidebar":false,"hide_sidebar_ad":false,"hide_all_ads":false},"yoast_head":"\nPAIN ASSESSMENT METHODS<\/span><\/h2>\n
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VETERINARY EXAMINATION<\/span><\/h2>\n
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PHYSIOLOGIC BIOMARKERS<\/span><\/h2>\n
OBJECTIVE MEASUREMENTS OF GAIT<\/span><\/h2>\n
OWNER ASSESSMENT OF ADL<\/span><\/h2>\n
Pain Conditions<\/span><\/strong><\/h3>\n
Owner Observations<\/span><\/strong><\/h3>\n
Challenges<\/span><\/strong><\/h3>\n
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CLINICAL MEASUREMENT INSTRUMENTS<\/span><\/h2>\n
Helsinki Chronic Pain Index<\/span><\/strong><\/h3>\n
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Canine Brief Pain Index<\/span><\/strong><\/h3>\n
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\nThe CBPI has been successfully used to assess response to therapy for OA11,12<\/sup> and, more recently, it has been shown to correlate with objective measurements of canine OA.13<\/sup><\/li>\n<\/ul>\n
\nDeveloped in 2003,14<\/sup> the Cincinnati Orthopedic Disability Index (CODI) uses client-specific outcome measures (CSOMs), making it different from other tools.<\/p>\n\n
\nCSOMs may have cross-over application to assessing OA in cats.17<\/sup><\/p>\n\n
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Liverpool Osteoarthritis in Dogs<\/span><\/strong><\/h3>\n
Canine CMIs: Where to Find Them<\/strong><\/h2>\n
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Scoring Feline Osteoarthritis<\/span><\/strong><\/h2>\n
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