Characteristics of lipid metabolism and fat distribution in patients with primary hyperparathyroidism and their Mendelian randomization study.

OBJECTIVE

Primary hyperparathyroidism (PHPT) is characterized by elevated parathyroid hormone (PTH) levels and hypercalcemia. Although research suggests a potential link between PTH and lipid metabolism, the evidence remains inconclusive. This study investigated lipid metabolism and fat distribution in PHPT patients.

METHODS

We studied 157 PHPT patients and strictly matched 1:1 controls based on sex, age, and BMI from our hospital (2020-2023). We recorded clinical data and used quantitative computed tomography (QCT) to measure lumbar spine bone mineral density and assess visceral and subcutaneous fat areas. Mendelian randomization analysis, utilizing genome-wide association study (GWAS) data, investigated the causal relationships between PHPT and various anthropometric measures, including body mass index (BMI), waist-to-hip ratio (WHR), and waist circumference (WC). Additionally, the analysis examined the associations between PTH levels and these same anthropometric traits: BMI, WHR, and WC.

RESULTS

The study included 47 males and 110 females in each group. There were no statistically significant differences between the two groups regarding BMI, triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total fat area (TFA), abdominal visceral fat area (VFA), subcutaneous fat area (SFA), or the VFA/SFA ratio (P > 0.05). After adjusting for albumin-corrected calcium, estimated glomerular filtration rate (eGFR), and 25-hydroxyvitamin D (25OHD), correlations between PTH and BMI, TG, TC, HDL-C, LDL-C, and the VFA/SFA ratio were not significant in either group (P > 0.05). Furthermore, when all the study subjects were divided into three groups based on PTH tertiles, correlations between PTH and the aforementioned indices remained nonsignificant after adjusting for albumin-corrected calcium, eGFR, and 25OHD (P > 0.05). In a two-sample Mendelian randomization study, no significant associations were observed between PHPT and BMI, WHR, or WC. Similarly, no significant associations were identified between PTH levels and BMI, WHR, or WC.

CONCLUSIONS

No statistically significant disparities were discerned in lipid metabolism markers or fat distribution between PHPT patients and controls. No significant correlation exists between PTH levels and lipid metabolism or fat distribution. Furthermore, no causal relationship was established between PHPT and BMI, WHR, or WC, nor between PTH levels and these anthropometric measures.