As baby boomers pass the half-century mark, many are celebrating with more than cake and ice cream: use of illicit drugs among 50- to 59-year-olds has nearly doubled during the past five years, according to a report from the Substance Abuse and Mental Health Services Administration (SAMHSA).

The report, An Examination of Trends in Illicit Drug Use among Adults Aged 50 to 59 in the United States (PDF), found that past-year drug use among this age group increased from 5.1 percent in 2002 to 9.4 percent in 2007. SAMHSA officials attributed the increase to more Baby Boomers entering their 50s and continuing their patterns of illicit-drug consumption.

“These findings show that many in the Woodstock generation continue to use illicit drugs as they age,” said SAMHSA Acting Administrator Eric Broderick. “This continued use poses medical risks to these individuals and is likely to put further strains on the nation’s health-care system — highlighting the value of preventing drug use from ever starting.”