Increased Protein Intake Is Associated With Uncontrolled Blood Pressure by 24-Hour Ambulatory Blood Pressure Monitoring in Patients With Type 2 Diabetes

Abstract

Objective: To analyze possible associations of dietary components, especially protein intake, with blood pressure (BP) during ambulatory BP monitoring (ABPM) in patients with type 2 diabetes.

Methods: In this cross-sectional study, BP of outpatients with type 2 diabetes was evaluated by 24-hour ABPM (Spacelabs 90207) and usual diet by 3-day weighed diet records. Patients were divided into 2 groups according to their daytime ABPM: uncontrolled BP (systolic BP ≥ 135 mmHg or diastolic BP ≥ 85 mmHg) and controlled BP (systolic BP < 135 mmHg and diastolic BP < 85 mmHg). Logistic regression models unadjusted and adjusted for possible confounders (covariates) were used to analyze the association of protein and uncontrolled BP.

Results: A total of 121 patients with type 2 diabetes aged 62.3 years, 54.5% of whom were women, were studied. The uncontrolled BP group had higher glycated hemoglobin (HbA1C) values (8.4 ± 2.0 vs 7.6 ± 1.3%; p = 0.04) and consumed more protein (20.0 ± 3.8 vs 18.2 ± 3.6% of energy; p = 0.01) and meat, (2.6 [1.45, 2.95] vs 2.0 [1.49, 2.90] g/kg weight; p = 0.04) than the controlled BP group. In a multivariate analysis, protein intake (% of energy) increased the chance for uncontrolled BP (odds ratio [OR] = 1.16; 95% confidence interval [CI], 1.02, 1.30; p = 0.02), adjusted for body mass index (BMI), HbA1C, low-density lipoprotein (LDL) cholesterol, number of antihypertensive medications, and ethnicity. Meat consumption higher than 3.08 g/kg weight/day more than doubled the chance for uncontrolled BP (OR = 2.53; 95% CI, 1.01, 7.60; p = 0.03).

Conclusion: High protein intake and meat consumption were associated with high daytime ABPM values in patients with type 2 diabetes. Reducing meat intake might represent an additional dietary intervention in hypertensive patients with type 2 diabetes.

AUTHOR CONTRIBUTIONS

C. M., T. P., R. A. S., and J. C. A. researched data. M. J. A. wrote the article. L. V. V. analyzed data and reviewed and edited the article. C. M., C. K. K., M. J. A., and J. L. G. contributed to the discussion and reviewed/edited the article. M.J.A. had primary responsibility for final content. All authors read and approved the final article.

Additional information

Funding

This study was partially supported by grants from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) PNPD-03021/09-2, FIPE-Hospital de Clínicas de Porto Alegre, and Conselho Nacional de Desenvolvimento Científico e Tecnológico-A576627/2008-9. C.B.M., T.P.P., and R.A.S. are recipients of scholarships from CAPES.