Study Suggests Strategies to Reduce Sodium Intake Likely to Decrease Stroke and Heart Disease, and Save Billions in Costs
FINDINGS:
- Strategies to reduce sodium intake on a population level are likely to substantially reduce the incidence of stroke and myocardial infarction, saving billions of dollars in medical expenses.
- Compared to the status quo, a government collaboration with the food industry would decrease the mean population sodium intake by 9.5% resulting in a 1.25 mmHg decrease in mean SBP, thereby averting 513,885 strokes and 480,358 myocardial infarctions (MIs) over the lifetime of adults age 40-85. This also would increase quality-adjusted life years (QALYs) by 1.3 million and save $32.1 billion in direct medical costs.
- A tax on sodium would decrease sodium intake by 6% resulting in a 0.93 mmHg decrease in mean SBP, thereby averting 327,892 strokes and 306,137 MIs. This also would increase QALYs by 840,000 and save $22.4 billion over the same time period.
BACKGROUND:
American adults consume an estimated 3,900 mg of sodium per day, 75% of which comes from processed food, far exceeding the maximum recommended intake of 2,300 mg per day. Moreover, individuals with hypertension, African-Americans, and individuals older than age 40 are advised to consume no more than 1,500 mg of sodium per day. This study examined the health benefits and costs associated with myocardial infarction (MI) and stroke for two governmental strategies to reduce sodium intake in the U.S., using a mathematical model that projects cardiovascular event rates and costs among Americans aged 40 to 85 years. The two strategies were: 1) government collaboration with food manufacturers to voluntarily cut sodium in processed foods, modeled on the United Kingdom experience; and 2) a tax on sodium. The UK collaborated with their Food Standards Agency, an independent government department, to work with manufacturers in cutting sodium in processed foods, resulting in an estimated 9.5% decrease in population sodium intake over the last 5 years.
LIMITATIONS:
- Efforts to reduce population sodium intake could result in other dietary changes that are difficult to predict, e.g., people might consume more fats and sugars.
- This analysis did not incorporate the cost savings from treating fewer cases of hypertension, end-stage kidney disease, or hypertensive (non-ischemic) heart failure.
NOTE:
- An editorial appearing in the same issue states that "…Smith-Spangler and colleagues provide compelling evidence that a policy-driven approach can reduce sodium intake, save money, and save lives. They have appropriately analyzed research and considered a range of assumptions, and arrive at conclusion consistent with other studies." Frieden T and Briss P. We Can Reduce Dietary Sodium, Save Money, and Save Lives. Annals of Internal Medicine March 2, 2010 [E-pub]; Embargoed until March 1 2010, 5:00 pm (ET).
AUTHOR/FUNDING INFORMATION:
Dr. Smith-Spangler was supported by a VA Special Fellowship in Health Services Research. Drs. Smith-Spangler, Owens, and Garber are part of the VA Palo Alto Healthcare System. Drs. Owens and Garber also are part of HSR&D's Center for Health Care Evaluation in Palo Alto, CA.
Smith-Spangler C, Juusola J, Enns E, Owens D, and Garber A. Population Strategies to Decrease Sodium Intake and the Burden of Cardiovascular Disease in the United States, a Cost-Effectiveness Anaylsis. Annals of Internal Medicine March 1, 2010,e-pub ahead of print.
