Practice patterns for chronic hypoparathyroidism: data from patients and physicians in France

Abstract

Context: Recent guidelines have provided recommendations for the care of patients with chronic hypoparathyroidism. Very little is known about actual physicians' practices or their adherence to such guidelines.

Objective: To describe the physicians' practice patterns and their compliance with international guidelines.

Design: The cohort studies included were Épi-Hypo (118 physicians and 107 patients, from September 2016 to December 2019) and ePatients (110 patients, November 2019).

Methods: Internet-based cohorts involving all settings at a nationwide level (France). Participants were (i) physicians treating patients with chronic hypoparathyroidism and patients with chronic hypoparathyroidism either participating in the (ii) Épi-Hypo study (Épi-Hypo 2019 patients), or (iii) Hypoparathyroidism France, the national representative association (ePatients).

Results: The physicians' specialties were mainly endocrinology (61%), nephrology (28%), family medicine (2.5%), pediatrics (2.5%), rheumatology (2%), or miscellaneous (4%) and 45% were practicing in public universities. The median number of pharmaceutical drug classes prescribed was three per patient. The combination of active vitamin D and calcium salt was given to 59 and 58% of ePatients and Épi-Hypo 2019 patients, respectively. Eighty-five percent of ePatients and 87% of physicians reported monitoring plasma calcium concentrations at a steady state at least twice a year. In 32 and 26% of cases, respectively, ePatients and physicians reported being fully in accordance with international guidelines that recommend targeting symptoms, plasma calcium and phosphate values, and urine calcium excretion.

Conclusions: The care of patients with chronic hypoparathyroidism involves physicians with very different practices, so guidelines should include and target other specialists as well as endocrinologists. Full adherence to the guidelines is low in France.

Keywords: epidemiological studies; hypocalcemia; hypoparathyroidism; physicians; practice patterns.

Figure 1

Flowcharts of the analyzed cohorts. (A) From September 2016 to November 2019, 171 physicians were enrolled in the Épi-Hypo study. Among them, 118 (69%) answered the questionnaire about their habits in terms of follow-up of patients with chronic hypoparathyroidism; their data are presented as ‘Physicians’ data. (B) In November 2019, we conducted an online questionnaire dedicated to patients living with chronic hypoparathyroidism. We collected 155 answers. Among them, 110 (71%) were analyzed; we present that data as the ‘ePatients’ data. (C) From September 2016 to September 2019, 939 patients were enrolled in the Épi-Hypo study. Among them, 916 (98%) met the inclusion criteria. Finally, 107 (12%) had a follow-up visit in 2019; we present that data as the ‘Épi-Hypo2019’ data.

Figure 2

Combinations of treatment during chronic hypoparathyroidism. (A) Among 110 patients in the ePatients cohort, 109 (99%) were treated with an oral calcium supplement (Ca salt), native vitamin D (native vitamin D), active analogs of vitamin D (active vitamin D), and/or teriparatide (PTH(1–34)). (B) Among 107 patients of the Épi-Hypo 2019 cohort, 105 (98%) were treated with one or more of those therapeutic classes. Data are presented as percentages (%) of the total answers.

Figure 3

Trends in follow-up habits during chronic hypoparathyroidism. (A) Data from the ‘Physicians’ cohort (blue, n = 118) show that they are more akin to checking plasma calcium (PCa) twice a year, while the ePatients (green) report a broader distribution (more frequent checks), and data from the Épi-Hypo 2019 (orange, n = 107) cohort report less frequent measurements of PCa (P < 0.001). In the ePatients (green) who reported screening for PCa (n  = 93), the distribution was broader. (B) The most frequently checked organs during chronic hypoparathyroidism are the kidneys, eyes, bone (by bone mineral density, BMD), and brain. Some ePatients and physicians also reported other organs (such as the heart) that could be checked. Of note, no data (NA) are available regarding bone or other follow-up from the Épi-Hypo 2019 cohort, and because the questions were added later, only 35 and 26 physicians answered whether they screened for BMD and brain, respectively. (C) Venn diagram showing the combinations of usual follow-up during chronic hypoparathyroidism by physicians: among the 118 physicians of the cohort, 111 (94%) follow kidney imagery, ask for eye checks, and/or checked PCa (at least twice a year). (D) Venn diagram showing the combinations of usual follow-up during chronic hypoparathyroidism reported by ePatients; among the 110 patients of the cohort, 93 (85%) were followed with kidney imagery, asked for eye checks, and/or checked for PCa (at least twice a year). Data are presented as percentages (%) of the total answers.

Figure 4

Plasma calcium targets during chronic hypoparathyroidism and values reached. While physicians (blue) and ePatients (green) report a targeted plasma calcium concentration mainly in the lowest range of the normal values (2.0–2.2 mM), the values observed (i.e. measured) in the Épi-Hypo study (orange) show a broader distribution that is significantly higher.

Figure 5

Indicators used as targets in the treatment during chronic hypoparathyroidism. (A) Venn diagram showing the combinations of indicators used by physicians: among the 118 included physicians, 115 (97%) targeted symptoms, plasma calcium (PCa), plasma phosphate concentration (PPi), and/or calciuria (UCa). (B) Venn diagram showing the combinations of indicators used by ePatients: among the 90 included ePatients who knew the indicator(s) of their treatment, 89 (99%) reported symptoms, PCa, PPi, and/or UCa as indicators. Of note, the combination PCa-UCa accounted for 76 and 70% of cases in the physicians and ePatients data, respectively. Data are presented as percentages (%) of the total answers.