Before 2010, nearly half of Americans did not recei

ve routine clinical preventive services that are known to save lives, researchers at the U.S. Centers for Disease Control and Prevention reported Thursday.

Their analysis, detailed in a supplement to the Morbidity and Mortality Weekly Report, examined how many people with vascular heart disease were prescribed aspirin or antiplatelet therapy to prevent heart disease (just 46%) and how many adults with hypertension had their blood pressure under control (just 43%). Only 28% of adults between 18 and 64 had received the seasonal influenza vaccine. Only 7.6% of tobacco users over 18 were prescribed tobacco cessation medication.

Respondents did a bit better taking care of cholesterol tests, with 70% of men and women over 20 for whom screening was recommended reporting having been screened in the last five years; and with diabetes management, which 87% of adults over 18 with diagnosed diabetes keeping glycohemoglobin (a measure of hemoglobin in the blood to which glucose is bound) at or less than 9%.

(Statistics, which were collected over varying periods of time, are summarized in a table on this MMWR webpage.)

“The findings of this report indicate that tens of millions of people in the United States have not been benefiting from key preventive clinical services, and that there are large disparities by demographics, geography, and health care coverage and access in the provision of these services,” wrote CDC director Dr. Thomas R. Frieden, in the report’s foreword.

CDC researchers said the purpose of their investigations was to establish a baseline for use of preventive services before implementation of the healthcare reforms in the Affordable Care Act. That law, which was championed by President Obama at the beginning of his term and approved by Congress in 2010 -- and which has been argued over furiously ever since -- could impact future prevention trends because it requires many health insurance plans to provide preventive services without cost-sharing, they reported.

In 2011, the CDC reported in a statement, the Affordable Care Act gave about 54 million Americans at least one new free preventive service through private health insurance plans.

The Supreme Court is expected to rule on the constitutionality of the Affordable Care Act later this month.

[For the Record, 9:10 a.m. June 15: The headline on an earlier version of this post said “Half in U.S. did not seek preventive care before 2010, CDC says.” The CDC report did not address how many people sought certain preventive care services before 2010; rather, it noted how many people received the services. The headline has been changed to reflect that.]