Patients who undergo emergency treatment at the hands of surgeons aged 60 or older are more likely to survive, according to new research.
The findings suggest doctors improve their surgical skills with extra years in practice.
Researchers found that patients undergoing emergency operations who are treated by older surgeons have slightly lower death rates in the first few weeks after their op than patients treated by surgeons aged less than 40 within the same hospital.
There was no evidence that death rates differ between male and female surgeons, according to the findings published by The BMJ.
The researchers said their findings suggest that for every 333 patients who undergo surgery, one fewer death would occur if quality of care was the same between younger and older surgeons.
They said that the relationship between surgical characteristics - especially age and sex of surgeons - and patient outcomes is not well understood.
The research team set out to investigate whether patient mortality differs based on age and sex of surgeons.
They analysed the 'operative mortality rate' - defined as death while in hospital or within 30 days of surgery - of patients aged 65 to 99 who underwent one of 20 major emergency surgical procedures at US acute care hospitals between 2011 and 2014.
After adjusting for a range of patient, surgeon and hospital characteristics that could have affected the results, they compared operative mortality according to surgeon age and sex.
A total of 892,187 patients were treated by 45,826 surgeons with an overall operative mortality rate of 6.4 per cent.
The researchers found that patient mortality was slightly lower for older surgeons than for younger surgeons within the same hospital: 6.6 per cent for surgeons aged less than 40, 6.5 per cent for surgeons aged 40 to 49, 6.4 per cent for surgeons aged 50 to 59, and 6.3 per cent for surgeons aged 60 or over.
But the mortality rate didn't differ meaningfully between male and female surgeons.
When the researchers analysed the data by both surgeon age and sex, patient mortality declined with surgeon age for both male and female surgeons, with female surgeons in their 50s showing the lowest operative mortality across all groups.
Operative mortality did not differ between male and female surgeons by patient illness severity or for individual procedures.
And there was no evidence that mortality differed by surgeon age or sex for non-emergency procedures.
Practice makes perfect
Previously, the researchers found worse outcomes among patients treated by older hospital physicians, which they attributed to practice changes since training, and possibly poor adherence to guidelines.
In contrast, the new findings suggest improved surgical skills with extra years in practice.
The researchers pointed out that it was an observational study, so no firm conclusions can be drawn about cause and effect, and the findings may not be applicable to other outcomes, such as patient experience or complication rates.
But they said the study was large, and was able to account for a wide range of potentially influential factors.
Study author Assistant Professor Yusuke Tsugawa, of David Geffen School of Medicine at UCLA in Los Angeles, said: "Our finding that younger surgeons have higher mortality suggests that more oversight and supervision early in a surgeon’s career may be useful and at least warrants further investigation."
He added: "Equivalent outcomes between male and female surgeons suggest that patients undergoing surgery receive high-quality care irrespective of surgeon sex.”