Weekend specialist intensity and admission mortality in acute hospital trusts in England: a cross-sectional study

Abstract

Background: Increased mortality rates associated with weekend hospital admission (the so-called weekend effect) have been attributed to suboptimum staffing levels of specialist consultants. However, evidence for a causal association is elusive, and the magnitude of the weekend specialist deficit remains unquantified. This uncertainty could hamper efforts by national health systems to introduce 7 day health services. We aimed to examine preliminary associations between specialist intensity and weekend admission mortality across the English National Health Service.

Methods: Eligible hospital trusts were those in England receiving unselected emergency admissions. On Sunday June 15 and Wednesday June 18, 2014, we undertook a point prevalence survey of hospital specialists (consultants) to obtain data relating to the care of patients admitted as emergencies. We defined specialist intensity at each trust as the self-reported estimated number of specialist hours per ten emergency admissions between 0800 h and 2000 h on Sunday and Wednesday. With use of data for all adult emergency admissions for financial year 2013-14, we compared weekend to weekday admission risk of mortality with the Sunday to Wednesday specialist intensity ratio within each trust. We stratified trusts by size quintile.

Findings: 127 of 141 eligible acute hospital trusts agreed to participate; 115 (91%) trusts contributed data to the point prevalence survey. Of 34,350 clinicians surveyed, 15,537 (45%) responded. Substantially fewer specialists were present providing care to emergency admissions on Sunday (1667 [11%]) than on Wednesday (6105 [42%]). Specialists present on Sunday spent 40% more time caring for emergency patients than did those present on Wednesday (mean 5·74 h [SD 3·39] vs 3·97 h [3·31]); however, the median specialist intensity on Sunday was only 48% (IQR 40-58) of that on Wednesday. The Sunday to Wednesday intensity ratio was less than 0·7 in 104 (90%) of the contributing trusts. Mortality risk among patients admitted at weekends was higher than among those admitted on weekdays (adjusted odds ratio 1·10, 95% CI 1·08-1·11; p<0·0001). There was no significant association between Sunday to Wednesday specialist intensity ratios and weekend to weekday mortality ratios (r -0·042; p=0·654).

Interpretation: This cross-sectional analysis did not detect a correlation between weekend staffing of hospital specialists and mortality risk for emergency admissions. Further investigation is needed to evaluate whole-system secular change during the implementation of 7 day services. Policy makers should exercise caution before attributing the weekend effect mainly to differences in specialist staffing.

Funding: National Institute for Health Research Health Services and Delivery Research Programme.

Figure 1

Specialist hours, specialist intensity, and emergency admissions The figure shows the estimated total hours for specialists attending emergency admissions on Wednesday, June 18, 2014 (A), and Sunday, June 15, 2014 (C), against the mean number of emergency admissions for Wednesdays or Sundays in 2013–14, for the 115 trusts responding to the point prevalence survey; and the specialist intensity measure (hours per ten emergency admissions) against the mean number of admissions for Wednesdays or Sundays (B, D). Pearson correlations (r) and p values are shown.

Figure 2

Specialist intensity by trust For each trust, the bars represent specialist hours per ten emergency admissions from the point prevalence survey for Wednesday, June 18, 2014, and Sunday, June 15, 2014. Trusts are shown in decreasing order of the plotted intensity ratios, defined as the relative sizes of the bars.

Figure 3

Trust-specific weekend mortality Mortality odds ratios (in increasing order) for weekend to weekday admissions for the 115 trusts contributing to the point prevalence survey. Bars show 95% CIs from logistic regression analysis.

Figure 4

Weekend mortality effects and specialist intensity ratios Mortality odds ratios for weekend to weekday admissions, and specialist intensity ratios for the 115 trusts contributing to the point prevalence survey. Pearson correlations (r) and p values are shown.