Understanding the biases to sepsis surveillance and quality assurance caused by inaccurate coding in administrative health data

PURPOSE

Timely and accurate data on the epidemiology of sepsis are essential to inform policy decisions and research priorities. We aimed to investigate the validity of inpatient administrative health data (IAHD) for surveillance and quality assurance of sepsis care.

METHODS

We conducted a retrospective validation study in a disproportional stratified random sample of 10,334 inpatient cases of age ≥ 15 years treated in 2015-2017 in ten German hospitals. The accuracy of coding of sepsis and risk factors for mortality in IAHD was assessed compared to reference standard diagnoses obtained by a chart review. Hospital-level risk-adjusted mortality of sepsis as calculated from IAHD information was compared to mortality calculated from chart review information.

RESULTS

ICD-coding of sepsis in IAHD showed high positive predictive value (76.9-85.7% depending on sepsis definition), but low sensitivity (26.8-38%), which led to an underestimation of sepsis incidence (1.4% vs. 3.3% for severe sepsis-1). Not naming sepsis in the chart was strongly associated with under-coding of sepsis. The frequency of correctly naming sepsis and ICD-coding of sepsis varied strongly between hospitals (range of sensitivity of naming: 29-71.7%, of ICD-diagnosis: 10.7-58.5%). Risk-adjusted mortality of sepsis per hospital calculated from coding in IAHD showed no substantial correlation to reference standard risk-adjusted mortality (r = 0.09).

CONCLUSION

Due to the under-coding of sepsis in IAHD, previous epidemiological studies underestimated the burden of sepsis in Germany. There is a large variability between hospitals in accuracy of diagnosing and coding of sepsis. Therefore, IAHD alone is not suited to assess quality of sepsis care.

Influence of Left Atrial Appendage Amputation on Natriuretic Peptides-A Randomized Controlled Trial

BACKGROUND

Closure or amputation of the left atrial appendage (LAA) is a common therapy for atrial fibrillation (AF). As the LAA is a hormone-producing organ, however, amputation is still somewhat controversial. We examined patients after surgical AF therapy with or without LAA amputation to determine the influence of LAA amputation on pro-atrial natriuretic peptide (proANP) and B-type natriuretic peptide (BNP) plasma levels and on clinical severity of heart failure.

METHODS

Twenty-one consecutive patients were prospectively randomized to either undergo LAA amputation (n = 10) or no LAA amputation (n = 11) between 05/2015 and 10/2015. All patients underwent coronary and/or valve surgery and concomitant AF surgery with either cryoablation (n = 3) or radio frequency ablation (n = 17). ProANP and BNP levels were measured preoperatively and until 800 days postoperatively.

RESULTS

Baseline proANP values were comparable between the groups (without LAA amputation: 4.2 ± 2.1 nmol/L, with LAA amputation: 5.6 ± 3.6 nmol/L). Postoperatively, proANP levels rose markedly in both groups. Even after LAA amputation, proANP levels remained elevated for 7 days postoperatively but fell to baseline levels at day 31 and remained on baseline level at 800 days postoperatively. ProANP levels in the LAA amputation group (5.8-9.7 nmol/L) were not significantly lower than in the group without LAA amputation (9.2-14.1 nmol/L; p = 0.357). BNP levels also rose after surgery in both groups until day 7. At 800 days after surgery, BNP levels were back at baseline levels in both groups. Clinical follow-up at 2 years postoperatively showed no difference in heart failure symptoms or need for heart failure medication between the groups.

CONCLUSION

In contrast to commonly held beliefs about the endocrine and reservoir functions of the LAA, there seems to be no clinically relevant detrimental effect of LAA amputation on natriuretic peptide levels and severity of heart failure until up to 2 years postoperatively.