# Karolinska thesis: 2.82% of Swedish surgery patients kept collecting opioids 4–6 months after operation

- Published: 2026-11-11 14:16 UTC
- Section: Life & Health › Medicine
- Tags: persistent opioid use after surgery, opioid dependence, postoperative opioid prescribing, Karolinska Institutet thesis, Claes Gedda, colorectal surgery pain, opioid-sparing analgesia, risk factors opioid use
- URL: https://realtech.media/news/rt-a0adb761397b5786d3c44044_karolinska_thesis_2/

**A thesis from Karolinska Institutet covers 1,245,211 Swedish surgical patients: risk factors for persistent opioid use and a 70% fall in median use with as-needed dosing.**

![Karolinska thesis: 2.82% of Swedish surgery patients kept collecting opioids 4–6 months after operation](https://realtech.media/media/2026/11/bb4776a16fe616b2.jpg)
*U.S. Army Southern European Task Force,  Africa, Wikimedia Commons, CC BY 2.0*

A doctoral thesis by Claes Gedda at the Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet, examined how often patients in Sweden keep using opioids after surgery, news-medical.net reports. [1] Opioids are effective for severe pain after an operation, but prolonged use is associated with dependence and overdose. [1]

The largest study included 1,245,211 adults who underwent surgery in Sweden between 2018 and 2022 and had not collected opioids for most of the year before the operation. [1] Of them, 35,132 people, or 2.82 per cent, collected opioids both during the first three months and during months four to six after surgery. [1] According to Gedda, this corresponds to about 7,000 patients a year in Sweden who collect opioids long after they should have recovered. [1]

## Risk factors for persistent opioid use

The risk was higher among older people and among those with greater comorbidity, a recent cancer diagnosis, chronic pain, anxiety or depression, and alcohol or drug problems. [1] Emergency surgery was also linked to a higher risk. [1] Patients who collected opioids during the first week after surgery were more than twice as likely to still be collecting them several months later. [1]

Gedda notes that part of the risk can be identified before surgery, and that post-operative prescribing is a factor the healthcare system can influence. [1]

## Reducing opioid use after major surgery

A separate study covered 842 patients who underwent major colon and rectal surgery. [1] In it, opioids were given as needed rather than on a fixed schedule, alongside other pain-relieving medicines. [1] Over four years, the median consumption of opioids fell by 70 per cent. [1] Towards the end of the study, almost one in three patients received no opioids at all during the first six days after surgery. [1]

The author points out that it is not yet known whether reduced early use also lowers the risk of long-term use, and that this needs further investigation. [1]

The thesis, titled "New persistent opioid use after surgery: Epidemiology and potential alternatives to opioids", was supervised by Mattias Soop at the same department. The public defence is scheduled for 4 December 2026. [1]

## Sources

1. [news-medical.net](https://www.news-medical.net/news/20261110/Swedish-study-identifies-risk-factors-for-prolonged-opioid-use-after-surgery.aspx)

---

Source: RealTech, realtech.media — https://realtech.media/news/rt-a0adb761397b5786d3c44044_karolinska_thesis_2/