A new study by Dutch doctors paints a stark picture of nicotine addiction among secondary school pupils, with more than a third of teenage smokers reporting that they wake up at night because they need nicotine.

The findings, published in the European Journal of Pediatrics, underline what researchers describe as an “unexpectedly high” level of dependency and the mental stress that night-time vaping can cause.

The study surveyed 978 pupils at five secondary schools across the country. Almost half of them — 396 teenagers — said they had smoked or vaped in the past year, and 183 reported doing so daily.

Most started using nicotine around the age of 13, often progressing to cigarettes and “underscoring policymakers’ responsibility to limit the tobacco industry’s influence and reduce youth access to nicotine products,” the researchers said.

Doctors involved in the study said the night-time use of e-cigarettes is a clear indicator of dependence. They also warned that many parents remain unaware their children smoke. When parents do know, they said, it is often easier for teenagers to seek help to stop.

Addiction expert Reinout Wiers, a professor of developmental psychopathology at the University of Amsterdam told the Volkskrant  he was surprised by how many teenagers vape at night. “I find it alarming,” he said.

E-cigarette vapour contains substances that can irritate or damage the respiratory system, and users face an increased cancer risk. Most vapes contain nicotine, which is highly addictive and especially risky for teenagers because their brains are still developing. Vapes cannot be sold legally to the under-18s.

Nicotine also acts as a stimulant. “Your heart rate goes up. If you take it at night, you’re less likely to fall back asleep,” Wiers said. “Poor sleep is a direct route to mental health problems and poor performance at school.”

The findings come as the government launches a new anti-vaping campaign. Lung specialists and addiction doctors have repeatedly warned about the growing popularity of vapes.

At least five teenagers and young adults in the Netherlands have almost died after excessive vaping and four were kept in an artificial coma for a longer period, RTL Nieuws said earlier this year.