An easy-to-use scale accessing the severity of 17 symptoms linked to hypoparathyroidism from a patient’s perspective has been developed by researchers.
If confirmed in future tests, this scale could be useful in evaluating disease burden and treatment effect in people with disease.
The results, “Assessing the Patient Experience of Hypoparathyroidism Symptoms: Development of the Hypoparathyroidism Patient Experience Scale-Symptom (HPES-Symptom),” were published in the journal The Patient – Patient-Centered Outcomes Research.
Patients with hypoparathyroidism (HP), a rare condition marked by insufficient levels of parathyroid hormone (PTH), often report a substantial burden of illness, with severe physical and cognitive symptoms.
These symptoms weigh on patients’ health-related quality of life, regardless if they are receiving standard-of-care (calcium and vitamin D supplements) or PTH replacement therapy.
While several validated surveys have tried to determine to what extent patients’ quality of life is impacted, these tools are not disease-specific and do not address a number of HP-related symptoms, including cognitive problems, fatigue, decreased muscle strength, or the effect of post-surgical hypoparathyroidism (an underactive thyroid).
Recognizing the “need to better understand, from the patient’s perspective, the signs and symptoms experienced with HP,” researchers with Ascendis Pharma and The Brod Group (whose specialty is patient-centered outcomes and research designs) developed a patient-reported outcome survey called the Hypoparathyroidism Patient Experience Scale-Symptom (HPES-Symptom).
Ascendis is developing a potential treatment for hypoparathyroidism, TransCon PTH, a long-acting parathyroid hormone designed to be a once-daily replacement therapy. It is opening a Phase 2 trial (NCT04009291) testing the safety, tolerability, and efficacy of increasing doses of TransCon PTH against placebo in 40 adults with HP at sites in the U.S., Europe, and Canada. Contact information is available here.
To create the tool and identify the most relevant signs and symptoms of HP, researchers interviewed five clinical experts and 42 adults with HP in the U.S.
Most patients reported experiencing tingling/numbness/paresthesia (88%), muscle cramping (86%), and physical fatigue (83%). The majority (86%) also complained of cognitive problems, including impaired memory (57%), difficulties participating in a conversation (50%), and a lack of concentration/focus (43%).
Based on these reports, researchers created a list of 17 major symptom items for the new scale. These were: muscle cramps, muscle spasms, muscle twitching, muscle weakness, tingling with numbness, tingling without numbness, pain, sensitivity to heat, feeling tired, trouble sleeping, heart problems, low energy, trouble remembering, trouble finding the right words, trouble concentrating, and trouble thinking clearly.
The draft scale was validated in a ‘cognitive debriefing‘ test, where a separate group of 16 adults with HP were asked to complete the test to see if there were any difficult items and confusing questions. Two weeks later, they answered it again, to control for the daily variability in symptoms. The survey took an average of four minutes to complete and patients did not consider it burdensome.
During this test, respondents were asked, for example: “In the past two weeks, because of your hypoparathyroidism, how often did you experience muscle cramping?” Response options included “Never,” “Occasionally (1–25% of the time),” “Sometimes (26–50% of the time),” “Often (51–75% of the time),” and “Very Often/Always (76–100% of the time).” A numeric scale was provided for each response option greater than “Never.”
After this cognitive debriefing, researchers reached a final, 17-item version of the HPES-Symptom.
“The study findings provide evidence of content validity for the validation-ready HPES-Symptom measure, which includes 17 items across two domains of signs and symptoms: Physical and Cognitive,” the researchers wrote.
This tool can be useful for “clinicians and researchers to assess the impact of treatments for this condition, including examining the differences between treatments, and assessment of the treatment risk/benefit ratio,” as well as assessing disease burden, they added.
More research is needed to confirm the reliability and validity of the HPES-Symptom in patients with HP.