Serum 25 (OH) Vitamin D Düzeyi Düşük Olan Kadınlarda Paratiroid Hormon Yanıtının Değerlendirilmesi

Öz

D vitamini eksikliği olan hastalarda kanda paratiroid hormon (PTH) salınımının artışı ile kalsiyum homeostazı sağlanmaktadır. Yapılan bazı çalışmalarda D vitamini eksikliği olan tüm hastalarda sekonder hiperparatiroidizmin gelişmediği öne sürülmüştür. Bu çalışmanın amacı serum 25(OH) vitamin D düzeyi düşük olan kadınlarda PTH yanıtını değerlendirmektir. Serum 25(OH) vitamin D konsantrasyonu 20 ng/ml’nin altında olan 58 ardışık hasta çalışmaya dahil edildi. Hasta -ların serum PTH ve kalsiyum değerleri de kaydedildi. 25(OH) vitamin D konsantrasyonunun 12 ile 20 ng/ml arasında olması ‘D vitamini yetersizliği’, 12 ng/mL altında olması ise ‘D vitamini eksikliği’ olarak tanımlandı. Hastaların yaş ortalaması 57.2 ± 15.3 (26-87) yıldı. Serum 25(OH) vitamin D düzeyleri 8.8 ± 3.9 ng/ml olarak tespit edilen hastaların %77.6’sında D vitamini eksikliği mevcuttu. Ortalama serum intakt PTH konsantrasyonu 68.2 ± 29.7 pg/ml idi. Sadece 27 hastada sekonder hiperparatiroidizm gelişmişti, geriye kalan hastaların serum PTH düzeyleri normaldi (< 67 pg/ml). Tüm hastaların kan kalsiyum seviyeleri de normal sınırlar içerisindeydi. Her iki grubun yaşları, serum PTH ve kalsiyum seviyeleri arasında istatistiksel olarak anlamlı bir farklılık yoktu. Sekonder hiperparatiroidizm, D vitamini yetersizliği saptanan hastaların (n= 13) 7’sinde, D vitamini eksikliği olanların (n= 45) ise 20’sinde gözlendi. Hastaların %53.4’ünde sekonder hiperparatiroidizmin gözlenmemiş olması, bu konuyla ilgili literatürdeki bazı çalışmalarla uyumludur. Serum 25(OH) vitamin D düzeyleri düşük olarak saptanan bu hastalarda azalmış PTH yanıtının nedenlerini araştıracak yeni çalışmalara ihtiyaç duyulmaktadır.

Anahtar Kelimeler

• Vitamin D eksikliği
• sekonder hiperparatiroidizm
• ftr

Evaluation of Parathyroid Hormone Response in Women with Low Serum 25(OH) Vitamin D Levels

Öz

Calcium homeostasis is maintained by increase in parathyroid hormone (PTH) secretion in patients with vitamin D deficiency. In several studies it was suggested that not all patients with hypovitaminosis D develop secondary hyperparathyroidism. The aim of this study was to evaluate PTH response in women with low serum 25(OH) vitamin D levels. 58 consecutive patients with a serum 25(OH) vitamin D concentrations <20 ng/ml were included in the study. Serum PTH and calcium levels of the patients were noted. Serum 25(OH) vitamin D concentrations between 12 and 20 ng/ml was defined as ‘D vitamin insufficiency’ and below 12 ng/ml was defined as ‘D vitamin deficiency’. The mean age of the patients was 57.2 ± 15.3 (26-87) years. Among all the patients with a mean serum 25(OH) vitamin D concentrations of 8.8 ± 3.9 ng/mL, 77.6% of them had D vitamin deficiency. The mean of serum intact PTH concentrations was 68.2 ± 29.7 pg/ml. Blood calcium levels of all patients were also within normal ranges. Secondary hyperparathyroidism was detected only in 27 patients, serum PTH levels of the others were normal (<67 pg/ml). There was no statistically significant differences between the mean age, serum PTH and calcium levels of the both groups. Secondary hyperparathyroidism was detected in 7 patients with vitamin D insufficiency (n= 13) and in 20 patients with vitamin D deficiency (n= 45). Secondary hyperparathyroidism was not observed in 53.4% of our patients, this result is consistent with several studies in the relevant literature. Further studies are necessary to investigate the causes of decreased parathyroid hormone responses in these patients who have low serum 25(OH) vitamin D levels .

Anahtar Kelimeler

• Vitamin D deficiency
• secondary hyperparathyroidism
• ftr

Kaynakça

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