Hubungan antara resistensi insulin dengan kadar Vitamin E plasma pada penderita Diabetes Mellitus tipe 2

KUSUMO, A. Sigit Ladrang Danar, Prof.dr. Paulus Wiyono, PhD.,SpPD-KEMD

2005 | Tesis | PPDS I Ilmu Penyakit Dalam

Latar belakang : Vitamin E merupakan salah satu antioksidan yang banyak dihubungkan dengan stres oksidatif dan diduga dapat menyeimbangkan redox intraseluler, sehingga akan menghambat pengaktivan jalur sensitif dan tidak akan terjadi resistensi insulin. Tujuan: Untuk mengetahui adakah hubungan antara resistensi insulin dengan kadar vitamin E plasma pada Diabetes Mellitus Tipe 2. Subjek dan metoda: Penelitian dilakukan dengan cara studi potong-lintang. Subjek penelitian adalah penderita DM tipe 2 yang berobat di poli klinik RS Dr. Sardjito dari bulan Maret-Oktober 2004. Didapatkan 70 subjek sesuai dengan kriteria inklusi. Subjek dikelompokkan menjadi 2 kelompok. Kelompok kadar HbA1c≤8,0% dan kadar HbA1c>8,0%. Masing-masing kelompok dibedakan lagi menjadi kelompok resistensi insulin ( HOMA-IR > 2,77) dan kelompok non resistensi insulin ( HOMA-IR ≤ 2,77). Analisis statistik dilakukan dengan membandingkan rerata kadar vitamin E plasma antara kelompok resistensi insulin dan non resistensi insulin. Analisis korelasi bivariate dan regresi linier digunakan untuk menilai hubungan antara resistensi insulin dengan kadar vitamin E plasma dan variabel lainnya. Hasil: Rerata umur subjek penelitian secara keseluruhan adalah 57,03 ± 9,7 tahun; rerata lama terdiagnosis DM 60,73 ± 52,52 bulan; rerata kadar HbA1c 8,12 ± 2,48 % dan rerata kadar vitamin E 1,62 ± 0,06 mg. Pada penderita DM dengan kadar HbA1c ≤ 8%, rerata kadar vitamin E pada penderita DM dengan resistensi insulin lebih rendah bila dibandingkan dengan rerata kadar vitamin E penderita DM tanpa resistensi insulin, meskipun hasilnya tidak berbeda bermakna (1,61 ± 0,058 mg vs 1,65 ± 0,06 mg; p = 0,091 atau 37,54 ± 1,36 mol vs 38,4 ± 1,4 mol). Ada korelasi negatif (r = - 0,013, p = 0,94 pada subjek dengan kadar HbA1c≤8% dan r=-0,024,p = 0,84 pada subjek dengan kadar HbA1c>8%) antara kadar vitamin E dengan HOMA-RI, meskipun secara statistik tidak bermakna. Hasil analisis regresi didapatkan bahwa HOMA-IR : 5,487 – (4,487 vitamin E). Kesimpulan: Tidak ada hubungan antara resistensi insulin dengan kadar vitamin E plasma pada penderita DM tipe 2.

Background: Vitamin E is an antioxidant that is most related with oxidative stress. Vitamin E can balance intraseluler redox, so that can inhibit sensitive pathway activity and inhibit insulin resistance. The aim: The study was aimed to investigate the relation between insulin resistance with vitamin E plasma level among type 2 diabetes. Subject and method: Research was conducted in cross-sectional design. Subject was type 2 diabetes patients who attended clinics of Dr. Sardjito Hospital between March and October 2004.There were 70 subjects fulfilled the inclusion criteria. Subjects were divided into two groups. Type 2 DM with concentrations of HbA1c≤8,0% and type 2 DM with concentrations of HbA1c>8,0%. The each group was divided into the insulin resistance ( HOMA-IR > 2,77) and the non-insulin resistance ( HOMA-IR ≤ 2,77). Statistical analysis was done by comparing the means of plasma concentrations of vitamin E between two groups. Bivariate corelations and linear regression models was used to identify potential correlation between insulin resistance (HOMA-IR) and plasma concentrations of vitamin E and the others variables. Result: In all subject, the avarage of age was 57,03 ± 9,7 years. The avarage DM duration was 60,73 ± 52,52 months, the mean of plasma concentrations of vitamin E was 1,62 ± 0,06 mg. In diabetic patients with concentrations of HbA1c,8,0%, the mean of plasma concentrations of vitamin E in the insulin resistance group was lower than insulin sensitive group (non insulin resistance group), but there was not significant (1,61 ± 0,058 mg vs 1,65 ± 0,06 mg; p= 0,09 or 37,54 ± 1,36 mol vs 38,4 ± 1,4 mol). No significant relation was found between the concentrations of vitamin E and HOMA-IR (r= - 0,058 ; p= 0,78). From linear regression models was found HOMA-IR : 5,487 – (4,286 vitamin E). Conclutions: There was no relation between insulin resistance and plasma concentrations of vitamin E in type 2 diabetes mellitus.

Kata Kunci : Diabetes Mellitus Tipe 2,Resistensi Insulin,Vitamin E,Stress Oksidatif, Type 2 DM - stress oxidative - vitamin E - insulin resistance