New US government figures forecast the nation’s spending on prescription drugs to increase an average of 6.5% a year between 2015 and 2022.

This projected growth is in marked contrast to the 0.8% drop reported in US prescription drug spending in 2012, from 2011’s growth of 2.9%, and will be due to increases in insurance coverage and in disposable income, enabling more consumers to fill prescriptions, according to the annual forecasts produced by the Centers for Medicare and Medicaid Services (CMS) Office of the Actuary.

Nevertheless, it points out, this 6.5% annual projected growth is below the yearly growth rate of 8.6% seen in 2000-09.

Last year’s dip was the result of a number of widely-used brand-name drugs losing patent protection, the report notes, and forecasts that low rates of grown in prescription drug spending, and hospital expenditures, will continue this year.

Spending growth for Medicare, the federal health programme for people aged 65 and over and some people with disabilities, has also slowed, down to 4.6% in 2012 from 6.2% the year before, for a total of $579.9 billion.

While increases in the number of Medicare enrolees, utilisation and input prices will lead to an annual increase of 7.4% during 2015-22, this will be well below the previous decade’s 9.3% rate of growth, as the Affordable Care Act (ACA) constrains fee-for-service and private plan payment growth, says the report.

Out-of-pocket spending will also be lower, as people have more affordable coverage, it adds. By 2022, the share of total US health spending attributable to out-of-pocket spending is projected to fall from 11.4% in 2012 to 9.1%, largely because of expanded insurance coverage through Medicaid and the marketplaces.

And per-person spending on Medicaid, the federal/state health programme for people on low incomes, will fall 2.8% in 2014, due to the entry into the programme of non-disabled children and younger and nondisabled adults. However, next year Medicaid will be covering nearly 9 million newly-insured Americans, and this will lead to an overall increase in programme spending of 12.2%, says the report, which will be published in the October issue of the journal Health Affairs.

• The CMS has also reported that over 6.6 million Medicare enrollees have saved more than $7 billion on prescription drugs as a result of the ACA, which President Barack Obama signed into law in March 2010.