TITLE:
Long Term Outcome of Bisphosphonate Therapy in Patients with Primary Hyperparathyroidism
AUTHORS:
Dalitso Segula, Tanya Nikolova, Eileen Marks, Lakshminarayan Ranganath, Vinita Mishra
KEYWORDS:
Primary Hyperparathyroidism, Bisphosphonates, Hypercalcaemia, Bone Mineral Density,
JOURNAL NAME:
International Journal of Clinical Medicine,
Vol.5 No.14,
July
23,
2014
ABSTRACT: Context:
Primary hyperparathyroidism (PHPT) is commonly associated with reduced bone
mineral density (BMD) presenting with osteoporosis, increasing the risk of bone
fragility fractures in these patients. Bisphosphonates, due to their anti-resorptive action, are known to improve the BMD and reduce the
risk of bone fragility fractures. Therefore, bisphosphonates are considered as an alternative to surgical treatment in
managing osteoporosis in PHPT patients. Aim: The aim of
this observational study was to assess the effect of long term bisphosphonate
therapy on BMD, bone fragility fracture and biochemical
markers of bone metabolism in patients with PHPT. Methodology: Fifty patients (mean age 74 years) with PHPT
who were treated with long term bisphosphonate
therapy were studied
retrospectively. The mean
baseline (before commencing bisphosphonate therapy) BMD T-scores for lumbar
spine (L2-L4) and left femoral neck were -2.5 and -2.1, respectively. Fourteen
patients had bone fragility fractures before initiation of bisphosphonate
therapy. Results: After an
average of 5 years of bisphosphonate treatment, there was a significant
increase in lumbar BMD T-score
(-2.5 to -2.1, p = 0.013) and a non-significant
change in left femoral neck BMD T-score (-2.1 to
-2.2, p = 0.497). There was no
increase in bone fragility fracture rate (p = 0.167).
Serum corrected calcium reduced from 2.74 mmol/L to 2.60 mmol/L (p 0.001) and urine calcium to creatinine ratio
from 0.70 to 0.55 (p 0.0001),
both within the reference range. Conclusions: Our study
suggests that long term bisphosphonate therapy improves lumbar BMD and prevents increase in
bone fragility fracture rate. Additionally it improves hypercalcaemia in PHPT.