Systemic hemodynamic changes in young and elderly normotensive individuals after ingestion of meals with high lipid, protein, and carbohydrate contents.

OBJECTIVES

The changes in blood pressure and in the cardiac function were studied in two groups of patients: an elderly group (EG) with 10 healthy normotensive elderly patients, and a young group (YG), with eight normal volunteers.

METHODS

Both groups were provided meals with high contents of lipids (LM), carbohydrates (CM), and proteins (PM). The systemic hemodynamic changes in each group were compared.

RESULTS

The maximum reductions (Δ(max)) observed in the mean arterial pressure in the EG were -10.3% and -8.9% for LM and CM, respectively (P<0.05), and -6.5% for PM (NS). No significant changes in the mean arterial pressure were found in YG. After the CM, EG showed a reduction in the total peripheral resistance (TPVRi) from 3212 ± 225 to 2537 ± 165 dyne s/cm(5); (P<0.05), and the cardiac index (CI) increased from 2.4 ± 0.17 to 2.8 ± 0.19 l/min/m(2); (P<0.05). After LM, the EG reduced the TPVRi from 3630 ± 273 to 2529 ± 247 dyne s/cm(5); (P<0.05), and CI increased from 2.1 ± 0.15 to 2.8 ± 0.15 l/min/m(2); (P<0.05). The PM did not alter CI. The YG showed, after CM, no significant decreases in TPVRi, but CI increased from 3.2 to 3.9 ± 0.16 ± 0.28 l/min/m(2); (P<0.05), and after the LM, there was an increase in CI from 3.3 to 4.2 ± 0.21 ± 0.17 l/min/m(2); (P<0.05) and a concomitant reduction in TPVRi from 2094 ± 173 to 1657 ± 139 dyne s/cm(5); (P<0.05).

CONCLUSION

In conclusion, the modifications in cardiac function in our elderly population were observed after eating and were related to the type of food ingested. No significant changes were observed in heart function after the ingestion of a protein meal.