Cost effective considerations

Researchers in the study in the BMJ developed a statistical model for 183 countries using data from 2010 to analyze sodium intake, blood pressure levels, the effects of sodium on blood pressure, the effects of blood pressure on cardiovascular disease, and cardiovascular disease rates.

To measure cost-effectiveness, the researchers used international dollars (the equivalent of the country specific purchase power of U.S. dollars) per D.A.L.Y. (disability adjusted life-years) saved over 10 years. The overall cost-effectiveness of the intervention was based on efforts in the United Kingdom and Turkey, which showed a government-supported program could reduce salt consumption by at least 10% over 10 years.

The study found that worldwide, a 10% reduction in sodium consumption over 10 years within each country was projected to average 5.8 million DALYs a year related to cardiovascular disease, at a population mean cost of $1.13 in international dollars per capita over the 10-year period.

One analysis in the United States estimated that an 11% sodium reduction, or about 0.4 gram per person per day, over 10 years would save from $4 billion to $7 billion in health care costs.

“Our novel results, together with prior studies in selected countries, provide evidence that a national policy for reduction in sodium intake is highly cost-effective and substantially more so than even highly cost-effective medical prevention strategies,” the study said. “This advantage likely arises from several factors. This policy is relative inexpensive to implement, utilizing system-wide ‘soft regulation’ rather than provision of individual level medical care. It also decreases cardiovascular risk at a population level, such that even small changes in distributions of risk factors translate into large clinical benefits, as compared with more intensive strategies delivered only to a subset of people.”

Dr. Mozaffarian demonstrated the cost-effectiveness of this strategy by pointing out statin drugs have an estimated cost-effectiveness of about $37,000 per DALY in the United States while the “soft reduction” government policy would have a cost-effectiveness of about $332 per DALY in the United States.

The study involved researchers from Stanford University in Stanford, Calif.; the Harvard T.H. Chan School of Public Health in Boston; the Tufts Friedman School of Nutrition Science and Policy in Boston, and the Cambridge Institute of Public Health in Cambridge, United Kingdom.

Awards from the National Heart, Lung, and Blood Institute and National Institute of Diabetes and Digestive and Kidney Diseases supported the research. Both institutes are part of the National Institutes of Health.

Both the study in the BMJ and the C.E.I. report recognized the worldwide heart health problem. An estimated 1,648,000 annual deaths from cardiovascular disease were attributable to excess dietary sodium in 2010, according to the study in the BMJ. Elevated blood pressure affects about 40% of the world’s adult population, according to the C.E.I. report.