Objective: This study explored whether the Pro12Ala polymorphism in the peroxisome proliferator-activated receptor-gamma (PPARgamma) is associated with blood pressure in subjects with type 2 diabetes.
Design: A community-based, cross-sectional observation study.
Setting: Primary care.
Patients: One hundred and ninety-two men and 192 women with type 2 diabetes who consecutively underwent annual follow-up.
Main outcome measure: The PPARgammaPro12Ala genotype was determined by polymerase chain reaction-based techniques. Associations between genotype and blood pressure were analysed by linear regression and expressed as differences in blood pressure (delta) with 95% confidence interval (CI).
Results: The mean systolic blood pressure and the diastolic blood pressure were 160 mmHg (standard deviation = 22.8) and 84 mmHg (standard deviation = 9.6), respectively. Subjects with Pro/Ala (24%) or Ala/Ala (2%) had lower diastolic blood pressure (delta = 2.8; 95% CI, 0.6-5.0) when adjusted for age and gender compared with Pro/Pro subjects (74%). This association was restricted to men (delta = 4.4; 95% CI, 1.3-7.4), who also had a borderline significant difference in systolic blood pressure (delta = 6.9; 95% CI, -0.8 to 13.8). In men the difference in diastolic blood pressure remained after adjustment for age, body mass index, serum triglycerides, serum insulin and haemoglobin A(1c) (delta = 4.6; 95% CI, 1.1-8.1). A subanalysis of normotensive men (n = 100) confirmed the difference associated with the Pro12Ala polymorphism in diastolic blood pressure (delta = 5.2; 95% CI, 0.6-10.0).
Conclusions: The common Pro12Ala polymorphism in PPARgamma is associated with lower diastolic blood pressure in male subjects with type 2 diabetes.