Effects of blood pressure and the renin-angiotensin system on platelet activation in type 2 diabetes.
Aims/Introduction:  Platelet-derived microparticles (PDMP) are released from the platelets either after activation or in response to physical stimulation in vivo. The present study examined the association between blood pressure and PDMP, and the effects of high-dose angiotensin receptor blockers (ARB) on PDMP in patients with type 2 diabetes.


METHODS
The study subjects consisted of 28 type 2 diabetes patients with blood pressure ≥130/80 mmHg who were treated with valsartan (80 mg daily). The patients were randomly assigned to take either 80 mg of telmisartan (Tel group) or 160 mg of valsartan (Val group) and then were followed up for 24 weeks. Thereafter, the patients were switched to combination therapy (5 mg of amlodipine with 40 mg of telmisartan [Tel group] or 80 mg of valsartan [Val group]) for 12 weeks.


RESULTS
Although the ambulatory blood pressure did not change, the PDMP levels were significantly decreased from baseline to week 24 (high dose ARB). In contrast, combination therapy reduced both blood pressure and PDMP levels compared with the baseline. Although the PDMP level was significantly correlated with the morning BP elevation at baseline and week 36 (combination therapy), this same relationship was not found at week 24. There were no significant differences in the blood pressure and PDMP levels between the two groups.


CONCLUSIONS
Patients with morning hypertension might be at risk for cardiovascular diseases. High-dose renin-angiotensin system inhibition and blood pressure control are both considered to reduce cardiovascular events in patients with type 2 diabetes. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2010.00048.x, 2010).
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Takashi
T
Uzu
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Masayoshi
M
Sakaguchi
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Atsuko
A
Tsuda
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Aya
A
Kadota
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Yukiyo
Y
Yokomaku
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Shinji
S
Kume
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Masami
M
Kanasaki
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Keiji
K
Isshiki
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Shin-Ichi
S
Araki
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Toshiro
T
Sugiomoto
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Hiroshi
H
Maegawa
Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan.
Atsunori
A
Kashiwagi
Morning blood pressure; Platelet activation; Renin‐angiotensin system