Clinical Applications: The Impacts of a Health-Related Quality-of-Life Questionnaire for Osteoarthritis Patients

Sponsored by an educational grant from Zoetis

KEY TAKEAWAYS

• Osteoarthritis (OA) is a widespread condition in both dogs and cats, often having a significant impact on patient quality of life.

• Pet owners are uniquely positioned to notice subtle changes in their pet’s behavior and attitude, making pet owner assessments an important tool in OA management.

• Measuring both physical and emotional well-being, the VetMetrica™ behavior-based questionnaire aims to accurately measure health-related quality of life in dogs and cats and can be used as a method of gauging response to treatment.

• A recent Zoetis publication used the VetMetrica questionnaire to measure HRQL in a dog receiving Librela™ (bedinvetmab injection) to control canine osteoarthritis pain, during which both physical and emotional well-being scores increased after initiation of therapy.

Osteoarthritis (OA) is a common condition in pets that is often diagnosed and managed by small animal general practitioners. OA is estimated to affect 20% of dogs >1 year of age,¹ and in studies of client-owned cats, >60% of cats ≥6 years of age and 90% of cats >12 years of age showed radiographic signs of OA.^2,3 These statistics underscore the widespread nature of osteoarthritis in companion animals.

OA-associated pain can have significant impacts on quality of life (QOL), emphasizing the need to manage this condition effectively. Although treatment cannot reverse or “cure” OA, the primary aim of OA treatment, along with optimizing diet, weight, and exercise, is focused on effective pain management, which can play a key role in helping restore mobility and improving QOL in affected patients.

To monitor a patient’s response to OA therapy and determine the most effective treatment for an individual patient, QOL monitoring is essential. In addition, studies have shown that pet owners are becoming increasingly interested in addressing not just their pet’s physical health but also their pet’s overall QOL.⁴ However, accurately evaluating QOL can be challenging in veterinary patients. In humans, QOL is typically self-reported via questionnaires, but with self-reporting not being feasible in veterinary patients, alternative methods for monitoring and measuring QOL are needed.

Pet owners are uniquely positioned to notice subtle changes in their pet’s behavior and attitude, considering how much time they spend with their pet; thus, veterinary QOL measurement tools typically focus on owner observations of behavioral changes. However, owner QOL assessments have limitations. Behavioral changes and their significance may vary among species, breeds, and even individual patients; for example, appetite fluctuations are often used as a QOL indicator, but appetite may differ in nature between a Labrador retriever and a toy breed.

Given the limitations of existing QOL assessments, there is a recognized need for accurate QOL assessments in pets. This is especially true for pets with chronic diseases such as OA, as QOL assessment tools can provide insight into the efficacy of various therapies for chronic diseases, helping veterinarians and pet owners alike make rational choices for improving QOL in pets.

Health-Related, Quality-of-Life Assessments in Veterinary Medicine

Although the term health-related QOL assessment (HRQL) is often used interchangeably with QOL, the actual definitions of these terms differ. QOL encompasses all aspects of a patient’s life, whereas HRQL specifically focuses on the effects of the illness and its treatment.

The VetMetrica™ behavior-based structured questionnaire aims to accurately measure HRQL in canine and feline patients.⁵ This assessment is taken online and can be completed by an owner in ≈5 minutes. The canine version of the VetMetrica questionnaire includes 22 unique assessment items. Each item consists of a simple descriptive term that is positive or negative in nature. Owners rate the extent to which each term applies to their pet on a scale of 0 to 6, with 0 indicating that the term does not apply to the pet at all and 6 indicating that the term is extremely descriptive of the pet. A high score on a positive term suggests a very good HRQL, whereas a high score on a negative term suggests a very poor HRQL.

After a pet owner enters their responses, the VetMetrica system creates a complete HRQL profile for the pet. This profile is made immediately available for the veterinarian to access online, and the veterinarian can then choose to make these results accessible to the client. Results are also available to VetMetrica for use in research and development.

Each dog receiving a VetMetrica HRQL assessment is assigned a score in 4 separate domains:

• Energy: Is the pet energetic/enthusiastic?

• Happiness: Is the pet happy/content?

• Activity: Is the pet active/comfortable?

• Calmness: Is the pet calm/relaxed?

In addition to these 4 scores, 2 summary scores are calculated for each patient: physical well-being and emotional well-being. The physical well-being score reflects energy and activity, whereas the emotional well-being score reflects happiness and calmness.

Each of these 6 scores is presented on a scale of 0 to 70. The scores are normalized such that the average healthy pet receives a score of 50; 70% of healthy animals tend to receive a score >44.8.⁶ It should be noted that patient scores on the VetMetrica HRQL assessment will fluctuate over time, depending on weather, stress, and other external factors; thus, veterinarians and clients should focus on overall trends, not individual measurements.

Finally, the minimal important difference on the VetMetrica HRQL assessment is 7 for dogs. In other words, an increase or decrease of ≥7 points in a dog is clinically significant.⁵

The Publication

The validated VetMetrica questionnaire to measure HRQL⁶ was used in a recent publication. A young, neutered male Staffordshire bull terrier diagnosed with OA pain was administered Librela (bedinvetmab injection) for control of that pain.

Librela was administered according to the label dosing chart on days 0, 28, and 56. VetMetrica assessments were performed by the client on days 0, 15, 24, 51, 59, and 61. On day 0 (treatment day), the patient received low scores in all categories: energy (23.9), happiness (24.7), activity (21.1), and calmness (33.6) The patient’s overall score for physical well-being was 22.5, and the score for emotional well-being was 29.2. These scores were well below the threshold of 44.8 at which 70% of healthy dogs score.⁶

Fifteen days after the dog’s first treatment with Librela, increases were seen in all categories. Energy increased from 23.9 to 41.1, happiness increased from 24.7 to 36.7, activity increased from 21.1 to 29.8, and calmness increased from 33.6 to 42.8. The patient’s overall score for physical well-being increased from 22.5 to 35.4, and the overall score for emotional well-being increased from 29.2 to 39.8. Each of these scores exceeded the minimal important difference for this test, indicating that the patient experienced clinically significant improvements in all 6 scores just 15 days after treatment with Librela.

On day 34 (after 2 treatments with Librela), further improvements were noted. The patient’s physical well-being (46.9) and overall emotional well-being (46.1) scores then exceeded 44.8, the threshold above which 70% of healthy dogs score.

Scores on days 51, 59, and 61 continued to show gradual improvement. By day 61, physical well-being (50.8) and emotional well-being (55.3) scores exceeded those expected in an average healthy dog, with the patient showing significant improvement as compared with day 0 scores.

Implications for Practice

This case study elucidates the impacts of OA in pets. Prior to treatment, the patient’s owner reported that the dog not only experienced poor physical well-being but also poor emotional well-being. During treatment with Librela, the patient made rapid, significant gains in both physical and emotional well-being, reflecting significant improvement in overall HRQL.

Veterinarians often tend to focus on physical function when evaluating the success of arthritis treatments (eg, is the dog still limping after treatment?). Although this is valuable information, it provides an incomplete assessment of the pet’s HRQL. This tendency toward incomplete assessment may be because an accurate, accessible way to assess a pet’s emotional state is not available; physical function is often easier to assess in a relatively objective manner.

The VetMetrica survey, as used in this case study, serves as a reminder of the importance of both physical and emotional well-being in pets. Measures of emotional well-being (eg, happiness, calmness) may be just as impactful to patients and clients as physical well-being, especially when managing OA and other chronic conditions. Even patients without significant activity gains can make dramatic HRQL gains in other areas.

Using Librela to Manage Canine Osteoarthritis

Nerve growth factor (NGF) is a key driver of OA pain and inflammation⁷ and is elevated in the synovial fluid of dogs with OA.⁸ Librela, the first and only monthly injectable anti-NGF monoclonal antibody, targets NGF in dogs, controlling the pain associated with OA. Librela is administered once monthly as a subcutaneous injection by a veterinary professional.

Librela has been approved as safe and effective for the control of pain associated with OA in dogs.^9-12 Librela is eliminated like naturally occurring antibodies, with minimal liver or kidney involvement.¹³ The most common adverse events reported in a clinical study were UTIs, bacterial skin infections, and dermatitis.¹⁰

To accurately measure response to Librela therapy, veterinarians can implement HRQL screenings and other client-reported measures. These HRQL assessments can not only provide a tool to assess treatment response and guide therapy, but they can also allow clients to be involved in monitoring their pet, leveraging the veterinarian–client relationship to make the best treatment decisions for every pet.

IMPORTANT SAFETY INFORMATION

See full Prescribing Information at LibrelaPI.com. For use in dogs only. Women who are pregnant, trying to conceive or breastfeeding should take extreme care to avoid self-injection. Hypersensitivity reactions, including anaphylaxis, could potentially occur with self-injection. LIBRELA should not be used in breeding, pregnant or lactating dogs. LIBRELA should not be administered to dogs with known hypersensitivity to bedinvetmab. The most common adverse events reported in a clinical study were urinary tract infections, bacterial skin infections and dermatitis.