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SOReg outcomes

Scandinavian data reports low mortality from surgery

The latest report from the Scandinavian Obesity Surgery Registry (SOReg) has revealed that bariatric surgery has a low mortality, low complication rate and results in a reduction of excess weight by 70 – 80% 12 to 18 months after surgery. Bariatric News talks exclusively to Dr Jan L Hedenbro, a member of the SOReg Steering Committee, about the aims, outcomes and implications of the registry.

The creation of SOReg was first prosed by Hedenbro in 2000, when he suggested the formation of a quality registry to the annual meeting of the Swedish Society for Upper Gastro-Intestinal Surgery. Subsequently, three organisations formally endorsed the registry’s formation; the Swedish Medical Society, the Board of Health and Welfare and the Association of Swedish Counties (the county is legally the body responsible for providing health-care to its inhabitants).

“Obesity surgery is a rapidly expanding field of surgery and we felt it was important to register accurately the quality of care given in terms of complications, hospital time etc,” said Hedenbro. “Apart from local one-department registries, SOReg is the first attempt to create a surgical database for report procedures and outcomes for bariatric surgery in Scandinavia.”

Jan Hedenbro

The system was ready for data entry trials in 2004 and became fully-functional in 2007. Since then, the registry has recorded over 26,000 cases from over 40 centres in Sweden and Norway, and collects data on more than 9,000 annual procedures.

“Although the Swedish Obese Subjects (SOS) study has over 2,000 recorded procedures, is not a cohort study but rather works with a sample of selected patients so it does not function as a good registry,” he added. “Even though many lessons can be learnt from it.”


The latest reports on data for operations in 2012 were published in April and July this year. They show that laparoscopic procedures have taken over almost completely from open procedures (92.62% vs. 6.3%), and gastric bypass is the dominant procedure with over 96% of all procedures recorded according to the registry.

Furthermore, the data demonstrates the safety of bariatric surgery, with the reported mortality rate from surgery reduced over the years from 0.1 down to 0.04 per cent, which is on par with cholecystectomy. The rate of any complication has dropped since 2007 from 15 to 7 per cent. About one third of these complications are severe (> Clavien-Dindo 3b), however complication rates differ between hospitals. Interestingly, the threshold for achieving the plateau phase of institutional learning seems to be around 200 cases per centre per year.

Although SOReg includes an estimated 98% of bariatric procedures performed in Norway and Sweden, in theory participation is not compulsory, explained Hedenbro.

“Most counties now make it (data entry onto SOReg) a prerequisite. The county places “orders” to the various hospitals in its catchment area, and bariatric surgery is “bought” only from some,” he explained. “The contribution from privately run hospitals is large, but the county has bought the operations so they are almost exclusively financed by tax money. As a result, patients paying privately for an operation is almost a vanishing phenomenon in Sweden, since the waiting lists have been shortened.”

The outcomes are reported by centre (rather than by surgeons), primarily for two reasons. Firstly, two surgeons are normally present at each operation and it was thought it would be impossible to register all possible combinations in a department.

“Basically, the responsibility of upholding quality in care is that of the chairman or departmental surgeon-in-chief,” he explained. “Reporting by hospital also allowed us to include all hospitals performing obesity surgery to participate in the registry.”

Dataset and collection

In order to establish the registry, Hedenbro and colleagues formed a group representing the geographical regions of Sweden, and discussed with representatives from other societies how to examine outcomes and categorise comorbidities.

“We decided on an operational definition, a patient has a comorbidity if on treatment,” he explained. “For example, if a comorbidity is found at baseline an extra question appears automatically at each follow-up visit to verify its presence or absence.”

In order to get funding in Sweden for a registry, the registry was required to measure patient-reported variables such as quality of life, and surgeons were already familiar with the SOS study, so decided to use SF-36 and Op-9 scales.

“The funding was surprisingly easy to obtain. We have discussed charging participating centres an annual fee, but so far this has not been necessary,” said Hedenbro. “Politicians are now beginning to realise the benefits of having a registry, especially since our reporting is on the net, and in Swedish.”

Data collection is facilitated by the web-based registry and operative details are entered by a surgeon or a scrub nurse. In centres where they do not have the facilities to enter the data directly, they fill out a paper form, which is entered online at a later date.

The database was designed so that it could be easily cross-run with other databases, such as the mortality registry or the registry for in-hospital care.

In addition, local research databases can be added in two ways: a certain number of variables in the main registry are open and can be locally defined; the complete datasets for any centre can be exported in excel format and then cross-matched with whatever the centres wishes to compare it to.

“Unfortunately, we have not been able to find an automatic way of entering lab data from the electronic lab reports,” he said. “We do see some problems when patients have been referred to another centre because of complications. The primary centre has the responsibility to enter all data for these patients, and sometimes communications are not as automatic as we might wish. So follow-up for these patients performed manually.”

The reports were previously published as a single publication with the data from the preceding year collected and analysed in June. The steering committee would approve the writing at a meeting in mid-August and the report would be published online in September.

“As of this year, we have decided to split the report in three parts: part 1 is already published on the web (volumes and activity), part 2 appeared in July (short-term complications), and part 3 will be publsihed in late autumn,” he explained. “They all cover what happened in 2012. Some of the more important aspects will be published in scientific journals, and will be longitudinal, looking at the development with time for various aspects.”


“On behalf of the SOReg Steering Committee, I would like to thank all the contributors to the registry not only for providing us with a tool that is unique in the world, but for performing such good surgery across the board,” said Hedenbro. “In the future, if we could overcome medico-legal issues, it would be beneficial to create a joint database including several European Union countries, so we could examine and learn lessons from how obesity surgery is practised across Europe.”

Additional members of the SOReg Steering Committee include: E Näslund (present chairman), I Näslund and J Ottosson (in charge of maintaining the database), A Bylund, A Laurenius, G Lundegård, P Möller and V Våge (representing Norway).

The latest report from SOReg was published in April 2013 and can be downloaded here

For more information regarding SOReg, please visit: