Uncontrolled Hypoparathyroidism Leads to Substantial Burden of Illness, Surveyed Physicians Say
People with chronic hypoparathyroidism not controlled by conventional therapy may experience a substantial burden of illness and impaired quality of life, mostly due to persistent symptoms and multiple co-existing conditions.
That finding comes from a survey-based study of attending physicians, “Burden of illness in patients with chronic hypoparathyroidism not adequately controlled with conventional therapy: a Belgium and the Netherlands survey,” which was published in the Journal of Endocrinological Investigation.
Oral calcium and vitamin D supplements are conventional treatments for hypoparathyroidism, which correct low blood calcium levels caused by the insufficient production of parathyroid hormone (PTH).
However, in many patients, conventional therapies fail to control calcium levels adequately. Even when they do, some people may continue to experience symptoms leading to persistent health problems and impaired quality of life.
Despite studies demonstrating the physical, cognitive, and emotional impact of hypoparathyroidism, research evaluating the burden of illness in those who failed to respond to conventional therapies are lacking.
Seeking to address this knowledge gap, researchers based at the Leiden University Medical Center in the Netherlands, along with colleagues at KU Leuven, in Belgium, and Shire Netherlands, designed a study that consisted of an online survey with endocrinologists in both countries and nephrologists from Belgium. All contacted physicians were either treating people with chronic hypoparathyroidism — low calcium levels in the presence of inappropriate or low PTH, and requiring treatment with active vitamin D — or supervising colleagues treating such patients and involved in treatment decisions concerning management of the condition.
The physicians were asked to provide data on one or two current cases of those whose disease was not adequately controlled by conventional treatments, which included the underlying cause, clinical manifestations, co-existing conditions (comorbidities), diagnostic reports, therapies received, and their perception of impaired quality of life.
A total of 36 endocrinologists and 29 nephrologists from Belgium, along with 28 endocrinologists from the Netherlands, participated in the survey.
Responding physicians provided data for 97 patients (66 women, 34 men); 60 cases were from Belgium and 37 from the Netherlands.
Altogether, mean age was 48.5 years, median duration of chronic hypoparathyroidism from the time of diagnosis was 5.1 years, and the median duration of uncontrolled hypoparathyroidism was 2.2 years.
Neck surgery was the most common cause of the condition, occurring in 67% of patients, which was performed a mean of 9.5 years before the survey.
According to physicians’ opinions, the most common reason for inadequate disease control was poor compliance (41%), followed by limited treatment choice (25%), co-existing conditions (21%), and treatment side effects (21%).
At diagnosis, 69 (71%) of patients had co-existing conditions, including high blood pressure (25%), kidney disease (20%), diabetes (12%), abnormal blood fat levels (11%), and being overweight (10%).
Treatments prescribed were calcium supplements (97%), active vitamin D (94%), and thiazide diuretics (7%), which reduce the amount of calcium lost through urine. Although patients generally remained on treatments prescribed at diagnosis, doses of both active vitamin D and calcium were increased in 47% of patients.
The most commonly reported symptoms were neuromuscular (85%) and neurological (67%), followed by gastrointestinal (31%), renal (20%), and cardiovascular manifestations (20%). Less frequent symptoms included respiratory issues, dry mouth, dental problems, weight loss, and cataracts.
At the time of the survey, 71% of patients had abnormal blood test values, most commonly calcium (91%), but also including phosphate and magnesium.
While 66% of endocrinologists and 45% of nephrologists used 24-hour calcium measurements to monitor hypoparathyroidism, no additional tests were used in 23% of patients. In Belgium, a higher percentage of patients had additional tests when treated by a nephrologist than an endocrinologist “because of the inherent increased risk of other morbidities associated with renal comorbidity,” the researchers wrote.
In the year before the survey, the primary reason for hospitalization was the inability to control chronic hypoparathyroidism — in 17% of patients.
As for quality of life, the physicians reported that 71% of patients experienced a decrease, 12% had no change, and 17% had an improvement since hypoparathyroidism onset.
Finally, the providers were asked to profile their patients concerning abnormal blood tests and the presence or severity of symptoms. The responses showed that about 50% of patients had abnormal blood tests along with absent or mild clinical symptoms.
“Patients with chronic hypoparathyroidism not adequately controlled on conventional therapy experience a substantial burden of illness, mainly due to persistence of symptoms and presence of multiple comorbidities,” the scientists concluded.
“We believe our findings hold significant clinical implications for the management of patients with chronic hypoparathyroidism by being instrumental in increasing awareness of the burden of illness associated with failure to adequately control the disease and of the need for optimizing treatment to alleviate or prevent this burden,” they added.