This is the first study to suggest that nursing ratios at the weekend are also important.
Sir Bruce Keogh, medical director of the NHS, has said hospitals must provide routine care seven days a week and hospitals must ensure sufficiently senior staff are on duty at weekends.
In addition the National Institute for Health and Care Excellence issued guidance on safe nurse to bed ratios in July. It stated that anything above one nurse to eight beds should trigger an urgent review.
The researchers from King's College London and the Royal College of Physicians analysed data from 56,666 patients admitted to 103 stroke units in England between June 1st 2011 and December 1st 1012.
They found no difference in death rates in stroke units where doctors did ward rounds seven days a week or just five days a week.
However there was a strong link between patient deaths and nursing ratios, suggesting that basic nursing care is also important for stroke survival.
It was found that units in 1.5 nurses per ten beds 15.2 per cent of patients died within a month compared with 11.2 per cent of patients on wards with three nurses for every ten beds at the weekend.
Lead author Dr Benjamin Bray said the average number of nurses per ten days was about two.
It was calculated that when there was one nurse for ten beds there was a 35 per cent increased risk of mortality when compared with two nurses per ten beds.
In addition there was a 20 to 30 per cent reduced mortality with four nurses per ten beds compared with two nurses.
View post:
Stroke patients are more likely to die if fewer nurses at weekends