Salt and hypertension: recent advances and perspectives

Area of Science:

• Cardiovascular Science
• Human Physiology
• Nutritional Science

Background:

• Dietary sodium intake is traditionally linked to hypertension development and maintenance.
• Existing evidence includes epidemiological data, animal studies, cellular investigations, and dietary intervention trials.

Purpose of the Study:

• To comprehensively review current evidence on the role of dietary sodium in hypertension.
• To explore the complexities and genetic influences on salt sensitivity of blood pressure.

Main Methods:

• Analysis of a global epidemiological study (>10,000 subjects) on sodium excretion and blood pressure.
• Review of animal and human studies investigating genetic factors in salt sensitivity.
• Examination of cellular mechanisms, including ion transport and calcium levels.
• Evaluation of dietary intervention trials for salt restriction in hypertensive patients.

Main Results:

• Significant relationships exist between sodium excretion and blood pressure, but they are not straightforward.
• Genetic factors significantly influence salt sensitivity of blood pressure in both animals and humans.
• Cellular studies identified increased sodium-lithium countertransport, sodium-hydrogen exchange, and cytosolic calcium in salt-sensitive individuals.
• Dietary salt restriction trials in hypertensive patients yielded generally disappointing results.

Conclusions:

• The role of sodium intake in hypertension is multifaceted, involving genetic and cellular components.
• Current data suggest genetic predisposition is crucial for understanding salt sensitivity.
• Despite extensive research, definitive conclusions and broad generalizations about sodium's role in hypertension remain elusive.