Endocrine Abstracts

JOINT1749

Background: Patients with hypoparathyroidism (HPT) experience impaired quality of life (QoL) due to poorly understood reasons. While QoL has traditionally been assessed using generic instruments such as the SF-36 questionnaire, disease-specific instruments like the HPES (Validated in several countries) and HPQ28 (validated only in German) have recently emerged, although their use remains limited.

Aims of the Study: Primary aims: to validate an Italian version of HPQ28 questionnaire; to evaluate QoL in hypoparathyroid subjects using both HPES and HPQ28. Secondary aims: to correlate questionnaire scores with clinical, biochemical and general characteristics of subjects; to establish potential thresholds for each questionnaire that can assist clinicians in identifying when HPT impacts QoL.

Materials and Methods: Cross-sectional study including 179 subjects divided into three groups. After applying exclusion criteria (other systemic or psychiatric diseases and TSH levels outside the normal range), the final study population included: 51 thyroidectomised subjects with HPT, 49 thyroidectomised subjects without HPT and 57 control subjects without HPT or hypothyroidism.

Results: The Italian version of HPQ28 demonstrated a high reliability at test-retest (Intraclass Correlation Coefficient > 0.70) and the results for total and domain scores were consistent with those obtained with the German validated version, allowing effective assessment of symptom burden. Patients with HPT showed a significantly impaired QoL at HPES-impact (20.5% vs 7.8%, P = 0.023) and higher symptom burden at both HPQ28 (29.8% vs 20.2%, P = 0.042) and HPES-Symptom (35.8% vs 16.2%, P = 0.011) compared to hypothyroid patients. Symptom burden was correlated with female gender in both HPQ28 (P = 0.040) and HPES-Symptom (P = 0.037) as well as with age at HPQ28 (P = 0.042), but not with biochemical parameters such as serum calcium or calcium-phosphorus product, whereas QoL, as measured by HPES-impact was unrelated to general, clinical, and biochemical characteristics. However, analysis of questionnaire results by calcium quartiles revealed a trend toward improved QoL in patients with calcium levels between 8.4 and 8.9 mg/dL (P = 0.051). Receiver operating characteristic (ROC) analyses and the Youden Index calculation identified provisional cutoffs (HPES-impact: 16.10%; HPES-Symptom: 18.22%; HPQ28: 22.61%) to better interpret scores after single administration. Questionnaire score below these cutoffs may identify patients with lower impact of HPT on QoL and symptom burden.

Conclusion: This study highlights the significant impairment of QoL in HPT, underlines the usefulness of disease-specific questionnaires, and confirms that QoL and symptom burden do not appear to be related to biochemical data.