To evaluate the association between postprandial and sleeping blood pressure (BP) variations in the non-diabetic elderly.Design and Method:
This observational and cross-sectional study evaluated systolic, diastolic, mean and pulse pressures, along with heart rate, in 69 non-diabetic elderly patients. Ambulatory BP monitoring was used for pressure and heart rate measurements. Three periods were selected: preprandial (two hours before lunch), postprandial (2 hours after lunch) and sleeping (8 hours). Each period was subdivided into six intervals with their respective means. BP variability rates and heart rate were evaluated according to the studied periods and were calculated using the time-rate index.Results:
Comparison of the means and BP variability between the preprandial, postprandial and sleeping periods revealed significant differences. For postprandial and sleeping systolic BP, the variations observed were 113.2 ± 15.3 mmHg and 108.5 ± 13.9 mmHg, respectively, P = 0.003. The same significant variations were observed with the other pressures studied (P <0.001), except for pulse pressure (Table 1). Associations between the postprandial and sleeping period variability rates were obtained for systolic BP (r = 0.27; P = 0.034; 95% CI: 0.059-0.132), diastolic BP (r = 0.35; P = 0.005; 95% CI: 0.050-0.112), mean arterial pressure (r = 0.46; P <0.001, 95% CI: 0.048-0.110), pulse pressure (r = 0.20; P = 0.128; 95% CI: 0.041-0.080) and heart rate (r = 0.02; P = 0.855; 95% CI: 0.023-0.046) (Figure 1).Conclusions:
Postprandial BP variation had a positive and significant correlation with sleeping BP variation. The presence of this association may become a complementary marker of future cardiovascular events. Other studies are needed to confirm this hypothesis.