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.

Elevated serum matrix metalloproteinase 7 levels predict poor prognosis after radical prostatectomy.

Elevated matrix metalloproteinase-7 (MMP-7) tissue expression and serum concentration have been shown to be associated with cancer progression and metastasis. The aim of our study was to assess the prognostic value of preoperative circulating MMP-7 levels in serum samples of patients with clinically localized prostate cancer. Furthermore, we compared the serum MMP-7 levels between patients with organ confined and metastatic prostate cancer. MMP-7 levels were measured in 93 patients with localized prostate cancer, 13 patients with distant bone metastasis and in sera of 19 controls using enzyme-linked immunosorbent assay. The results were compared to the clinical follow-up data. We did not find any significant difference in MMP-7 serum levels between patients and controls (p = 0.268). Circulating MMP-7 serum concentration was significantly elevated in patients with distant metastasis (p < 0.001). For the detection of distant prostate cancer metastasis, using a cut-off value of 3.7 ng/ml, a specificity of 69% and a sensitivity of 92% were observed. Multivariate analysis identified high MMP-7 serum concentration as an independent risk factor for prostate cancer-related death both in a preoperative and a postoperative model (p = 0.003 and 0.018, respectively). Furthermore, the evaluation of predictive models revealed that addition of serum MMP-7 levels to the preoperatively available predictors improves prognostic accuracy (the concordance index increased from 0.631 to 0.734 when MMP-7 was included). Based on these, we concluded that MMP-7 is a potential marker to identify patients with metastatic prostate cancer. In clinically localized prostate cancer, MMP-7 may provide independent prognostic information, thereby helping to optimize therapy decisions.