Asymmetric dimethylarginine levels in dipper and nondipper hypertensive patients

Öz

Objectives: Asymmetric Dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthesis and also is an indicator of endothelial dysfunction. Patients who have nondipper blood pressure pattern have been shown to exhibit more endothelial dysfunction than patients who has dipper blood pressure pattern. However, other en­dogenous markers, but not ADMA, are used to assess endothelial function in these studies. In our study, we used ADMA levels to compare differences in endothelial function between each groups. Materials and methods: This study includes 87 patients who admitted to Düzce University internal medicine and Cardiology outpatient clinics throughout 6 months and have been diagnosed previously as essential hyperten­sion and followed with medical therapy. Patients were di­vided into two groups as non-dippers and dippers, using ambulatory blood pressure measurement. Patients\' body mass index, Systolic blood pressure and diastolic blood pressure, triglycerides, total cholesterol, low density lipo­protein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, and ADMA levels were measured. Results: Age, BMI, and lipid values did not differ sig­nificantly between groups (p>0.05). Mean ADMA level was 1.29±0.13 in dippers, and that of non-dippers was 1.27±0.13μmol/L. ADMA levels did not differ significantly between the non-dipper and dipper groups (p=0.575). Conclusion: ADMA levels were found to be higher in hypertensive patients due to endothelial dysfunction. En­dothelial dysfunction was more frequent in patients who had nondipper blood pressure pattern than patients who had dipper blood pressure pattern. In our study, ADMA levels did not differ significantly between two patterns.

Anahtar Kelimeler

• Dipper-Hypertension, Non-Dipper-Hyperten­sion, ADMA

Dipper ve nondipper hipertansiyon hastalarında asimetrik dimetil arjinin düzeyleri

Öz

Amaç: Asimetrik dimetil arjinin (ADMA), nitrik oksit sen­tezinin endojen bir inhibitörü olup aynı zamanda endotel disfonksiyonunun bir göstergesidir. Non-dipper hipertan­siyon (HT) tipine sahip hastalarda yapılan çalışmalarda endotel disfonksiyonun dolayısıyla hedef organ hasarının dipper HT tipi olan hastalardan daha fazla olduğu göste­rilmiştir. Biz çalışmamızda bu iki grup arasında endotel fonksiyonu değişikliklerini ADMA seviyelerine bakarak karşılaştırdık. Gereç ve yöntem: Bu çalışmaya 6 ay içerisinde Düzce Üniversitesi Tıp Fakültesi iç hastalıkları ve kardiyoloji po­likliniğine başvuran ve daha önceden esansiyel HT tanı­sı konulup medikal tedavi ile takip edilen 87 hasta dahil edildi. Hastalar ambulatuar kan basıncı ölçümü yapıla­rak dipper ve non-dipper olmak üzere iki gruba ayrıldı. Hastaların vucut kitle indeksi(VKİ), sistolik kan basıncı ve diyastolik kan basıncı, trigliserid, total kolesterol, dü­şük dansiteli lipoprotein(LDL) kolesterol, yüksek dansiteli lipoprotein(HDL) kolesterol ve ADMA ölçümleri yapıldı. Bulgular: Grupların yaş, VKİ ve lipid değerleri arasında istatistiksel olarak fark yoktu (p>0.05). Dipper grubunda bakılan ADMA seviyeleri 1.29±0.17 μmol/L, non-dipper grubunda ise 1.27±0.13 μmol/L idi. Dipper ve non-dipper grupları arasında ADMA açısından anlamlı farlılık yoktu (p=0.575). Sonuç: ADMA seviyeleri HT hastalarında bozulmuş en­dotel fonksiyonuna bağlı olarak yüksek olarak bulunur. Kan basıncının non-dipper tipinde endotel disfonksiyonu dipper tipi olanlara göre daha fazladır. Çalışmamızda iki tip arasında ADMA seviyelerinde farklılık bulunamamış­tır.

Anahtar Kelimeler

• Dipper Hipertansiyon, Non-Dipper Hipertansiyon, ADMA

Kaynakça

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