Propensity Score-matched Case Control Research Articles

Risk factors and oncological outcomes of urethral recurrence in male patients with muscle invasive bladder cancer after radical cystectomy combined with urinary diversion: a propensity score-matched case control study.

Radical cystectomy (RC) is the primary treatment strategy for muscle invasive bladder cancer (MIBC). However, it carries a high risk of urethral recurrence (UR) in male patients. The risk factors and oncological outcomes of UR remain unclear. We aimed to identify the risk factors and oncological outcomes of UR in male patients with MIBC after RC combined with urinary diversion. After propensity score matching, we evaluated 137 male patients with MIBC who underwent RC combined with urinary diversion at our center between January 1, 2007 and December 31, 2015. Patient demographics, comorbidity, and perioperative data were recorded. Univariate and multivariate Cox proportional hazards regression were used to estimate the hazard ratio and 95% confidence intervals. Cancer-specific survival (CSS) and overall survival (OS) were measured using the Kaplan-Meier curve with log-rank test. P < 0.05 was considered statistically significant. Of the 310 patients, 30 (9.7%) patients underwent UR. In the matched group, the independent risk factors of UR were history of TURB (HR = 3.069, P = 0.018), tumor stage (T3 vs. T2, HR = 3.997, P = 0.014; T4 vs. T2, HR = 2.962, P = 0.015), and tumor multifocality (HR = 2.854, P = 0.011). The CSS and OS of patients with UR were equivalent to the patients without UR (P = 0.295, P = 0.616). This propensity score-matched case-control study showed that UR is not rare in male patients with MIBC after RC combined with urinary diversion. We identified three independent risk factors of UR: history of TURB, tumor stage, and tumor mutifocality. The oncological outcomes were equivalent between patients with and without UR. These findings could help improve treatment strategies and follow-up schedules.

Differential recurrence after laparoscopic incisional hernia repair: importance of a nationwide registry-based mesh surveillance.

Identification of suboptimal mesh products is essential to improve the outcome after hernia surgery. This study investigated whether a national clinical database combined with administrative registries may serve as a tool for postmarketing evaluation of mesh products for hernia surgery. This was a propensity score-matched case-control cohort study comparing outcomes in patients undergoing laparoscopic incisional hernia repair with either one particular mesh or any other synthetic mesh. Data on patients registered in the Danish Ventral Hernia Database between 2010 and 2016 were combined with administrative data from the Danish National Patient Registry. The primary outcome was operation for recurrence. Secondary outcomes were 30-day readmission, 30-day reoperation for complications (excluding hernia recurrence), and mortality after 30 and 90 days. In total, 740 patients who underwent repair with one particular mesh were matched with 1479 patients who received any other synthetic mesh. The rate of repair for hernia recurrence was significantly higher in the particular mesh group than in the reference group: 12·8 versus 6·3 per cent respectively (hazard ratio 2·09, 95 per cent c.i. 1·57 to 2·79; P < 0·001). Use of the particular mesh increased the risk of readmission (odds ratio (OR) 1·53, 1·16 to 2·01; P = 0·002) and reoperation for a complication (OR 1·60, 1·03 to 2·47, P = 0·030). No difference in mortality was found. Clinical registries with prospectively collected data can provide long-term surveillance of commercial mesh. Laparoscopic incisional hernia repair with one particular mesh was associated with an increased rate of short-term complications and double the risk of repair for recurrence.

Commentary on: Risk factors and oncological outcome for intravesical recurrence in organ-confined upper urinary tract urothelial carcinoma patients after radical nephroureterectomy: A propensity score-matched case control study

Commentary on: Risk factors and oncological outcome for intravesical recurrence in organ-confined upper urinary tract urothelial carcinoma patients after radical nephroureterectomy: A propensity score-matched case control study

Risk factors and oncological outcome for intravesical recurrence in organ-confined upper urinary tract urothelial carcinoma patients after radical nephroureterectomy: A propensity score-matched case control study.

Radical nephroureterectomy (RNU) is the primary treatment strategy for upper urinary tract urothelial carcinoma (UTUC); however, the prognosis is poor and recurrences are common. The risk factors for intravesical recurrence (IVR) remain inconsistent and unclear. Thus, we have identified the risk factors for IVR in patients with organ-confined UTUC. We retrospectively studied 229 patients with UTUC who underwent RNU combined with bladder cuff resection at our center between 1 January 2010 and 31 December 2015. After propensity score-matching, 204 patients were included in our study. Patient demographics, co-morbidities, and peri-operative data were recorded. Univariate and multivariate Cox proportional hazard regression were used to estimate the hazard ratio and 95% confidence intervals. Overall (OS) and cancer-specific survival (CSS) were measured using the Kaplan-Meier curve with a log-rank test. A p-value <0.05 was considered statistically significant. Of the 229 patients, 42 (18.3%) had IVR after 40 months (range, 24-56 months) follow-up. In the matched group, the independent risk factors for IVR were tumor diameter (HR=2.690, p=0.038) and tumor stage (T3 vs. T1, HR=3.363, p=0.019; T2 vs. T1, HR=2.835, p=0.022). OS and CSS were poor in patients with IVR than patients without IVR (p<0.0001). In this propensity score-matched case-control study, tumor diameter and tumor stage were shown to be independent risk factors for IVR in patients with organ-confined UTUC. Moreover, patients with IVR had poor prognosis than patients without IVR. Thus, more active postoperative surveillance and treatment strategies should be adopted for these patients, which may help improve treatment outcomes.

Outcomes of endoscopic submucosal dissection for gastric epithelial neoplasm in chronic kidney disease patients: propensity score-matched case–control analysis

Little is known about the outcomes of gastric endoscopic submucosal dissection (ESD) in patients with chronic kidney disease (CKD). We compared the efficacy and safety of ESD between CKD and non-CKD patients. From January 2005 to December 2014, 102 CKD patients underwent ESD for gastric neoplasms at a tertiary medical institution were reviewed retrospectively. A propensity score-matched control group (102 patients) was selected from non-CKD patients to compare clinical outcomes between CKD and non-CKD patients. En bloc resection (96.1%) and curative resection (88.2%) rates in the CKD group did not significantly differ from those in the non-CKD group. Median procedure times (25.0 vs. 21.5min, p = 0.734) and perforation risk (p = 0.480) were similar between groups. The CKD group showed a tendency towards more bleeding events (p = 0.052) and had a significantly longer hospital stay (p = 0.001). In a subgroup analysis, stage 3 CKD patients exhibited a bleeding risk comparable to that exhibited by non-CKD patients (HR 1.35; 95% CI 0.36-5.06; p = 0.654), whereas stage 4 (HR 5.79; 95% CI 1.52-22.0; p = 0.010) and stage 5 (HR 4.80; 95% CI 1.58-14.6; p = 0.006) patients showed higher bleeding risks than non-CKD patients. In a multivariate analysis, stage 4/5 CKD was a significant predictor for bleeding risk (HR 4.99; 95% CI 1.32-18.8; p = 0.018). ESD for gastric epithelial neoplasms can be performed in stage 3 CKD patients with comparable efficacy and safety to that performed in non-CKD patients. Stage 4 and 5 CKD patients should be closely monitored for bleeding events after ESD.

A dietary pattern rich in animal organ, seafood and processed meat products is associated with newly diagnosed hyperuricaemia in Chinese adults: a propensity score-matched case–control study

Previous studies have indicated that some food items and nutrients are associated with uric acid metabolism in humans. However, little is known about the role of dietary patterns in hyperuricaemia. We designed this case-control study to evaluate the associations between dietary patterns and newly diagnosed hyperuricaemia in Chinese adults. A total of 1422 cases and 1422 controls were generated from 14 538 participants using the 1:1 ratio propensity score matching methods. Dietary intake was assessed using a validated self-administered FFQ. Dietary patterns were derived by factor analysis. Hyperuricaemia was defined as concentrations of serum uric acid higher than 7 mg/dl (416·5 μmol/l) for men and 6 mg/dl (357 μmol/l) for women. Three dietary patterns were derived by factor analysis: sweet pattern; vegetable pattern; animal foods pattern. The animal foods pattern characterised by higher intake of an animal organ, seafood and processed meat products was associated with higher prevalence of newly diagnosed hyperuricaemia (P for trend<0·01) after adjustment. Compared with the participants in the lowest quartile of the animal foods pattern, the OR of newly diagnosed hyperuricaemia in the highest quartile was 1·50 (95 % CI 1·20, 1·87). The other two dietary patterns were not associated with the prevalence of newly diagnosed hyperuricaemia after adjustment. In conclusion, a diet rich in animal organ, seafood and processed meat products is associated with higher prevalence of newly diagnosed hyperuricaemia in a Chinese population. Further cohort studies and randomised controlled trials are required to clarify these findings.

Impact of inpatient mental health rehabilitation on psychiatric readmissions: a propensity score matched case control study

Background: Examination of readmission data is a standard method for evaluating health service outcomes. Limited work has evaluated the efficacy of mental health rehabilitation, despite the need for evidence-based approaches.Aims: To evaluate the impact of inpatient mental health rehabilitation using metrics of psychiatric readmissions routinely collected at occasions of service.Methods: Consumers (n = 252) of a nonacute inpatient mental health rehabilitation unit were case matched with normative clients from community mental health services. The impact of inpatient care was measured on: (1) the occurrence of a psychiatric readmission within 12 months of discharge; (2) the total number of psychiatric readmissions within 12 months of discharge; and (3) the number of days to a psychiatric readmission after discharge.Results: The proportion of consumers experiencing a readmission significantly decreased following inpatient care, comparable to the normative group. The number of readmissions also significantly decreased, approaching normative group levels, except in consumers with comorbid bipolar, substance use, or personality disorder. Time to a readmission significantly increased following inpatient care, approximating normative group values, and was related to the number of previous admissions.Conclusion: Routinely collected service data demonstrated nonacute inpatient mental health rehabilitation reduces re-hospitalization, which will have benefits for both consumers and health services.

DMARD use is associated with a higher risk of dementia in patients with rheumatoid arthritis: A propensity score-matched case–control study

BackgroundPatients with rheumatoid arthritis (RA) exhibit an increased risk of dementia. Disease-modifying antirheumatic drugs (DMARDs) are commonly used to slow RA progression, but studies investigating the relationship between DMARDs and dementia in patients with RA are lacking. We investigated the relationship between DMARDs and dementia in patients with RA. MethodsUsing the National Health Insurance Research Database, patients aged ≥20years, who were newly diagnosed with RA between 2000 and 2011 were identified. Patients with RA who had dementia comprised the dementia group, and patients with RA who did not have dementia comprised the control group. The groups were matched at a 1:1 ratio by the propensity score. DMARDs were categorized into conventional synthetic DMARDs (csDMARDs) and biological DMARDs (bDMARDs). Logistic regression models were used to calculate the odds ratio and 95% confidence interval (CI) to evaluate the association between DMARD use and the risk of dementia in patients with RA. ResultsA total of 957 patients with RA and dementia, and 957 patients with RA but not dementia, were enrolled. The risk of dementia was determined to be 1.63-fold higher in patients with RA with csDMARD use than in those without csDMARD use (95% CI=1.33–2.00). No significant risk of dementia was observed in patients with RA who used bDMARDs compared with their counterparts. However, patients with RA who used hydroxychloroquine, methotrexate, and sulfasalazine exhibited significant risks of dementia, irrespective of cumulative exposure days. ConclusionPatients with RA who used csDMARDs exhibit significant association with dementia.

Whether preoperative enlarged lymph nodes affect long-term outcome following laparoscopic radical gastrectomy for gastric cancer? A propensity score-matched case control study.

e15542 Background: The aim of this study was to investigate the feasibility and oncologic efficacy of laparoscopic radical gastrectomy (LG) for gastric cancer with enlarged lymph nodes (LNs). Methods: We prospectively collected data from 855 patients who underwent LG between December 2009 and May 2012 due to gastric cancer and retrospectively analyzed these patients. According to a long-axis diameter of lymph node (LN) as measuredpreoperatively, patients were divided into large ( > 10 mm) and small ( ≤ 10 mm) lymph node groups (LG and SG). The long-term outcomes were compared in the matched groups using 1:1 propensity-score matching method. Results: Beforematching, most clinicopathologic characteristics including tumor size and tumor staging were significantly different between the LG and SG. After matching, only pN stage and neoadjuvant chemotherapy (NC) significantly differed between the two groups. Beforematching, the LG compared with the SG was associated with more LNs retrieved; while after matching, number of LNs retrieved were similar between the two groups, and it wouldn’t decrease as enlarged LNs area increases. 835 of 855 (94.2%) patients completed postoperative follow-up, and the median follow-up period was 41 (range 3-65) months. Beforematching, the LG demonstrated significantly lower 3-year overall survival rate (64.4% vs. 84.8%, P < 0.001); and in the LG, 3-year overall survival rates were similar among patients with different total number of enlarged LNs area. After matching, the 3-year overall survival rate of LG were comparable with that of SG(81.1% vs. 72.4%, P= 0.066). Multivariate Cox regression showed pTNM stage was the only independent prognostic factor. Stratified analysis according to pTNM stage demonstrated that 3-year overall survival rates of each stage were similar between the LG and SG. Conclusions: LG is also a safe and feasible procedure for gastric cancer with enlarged LNs compared to those without enlarged LNs. And the total number of enlarged LNs area has no impact onlong-term outcome of patients with the same tumor stage.

Is It Time to Phase Out the Austin Moore Hemiarthroplasty? A Propensity Score Matched Case Control Comparison versus Cemented Hemiarthroplasty.

We compared the Austin Moore hemiarthroplasty versus cemented hemiarthroplasties using a propensity score matched cased control study. For a consecutive cohort of 450 patients with displaced intracapsular neck of femur fractures, 128 matched cases in each group were selected based on age, gender, walking status, nursing home residency, delays in surgery, ASA score, and the Charlson comorbidity score. At a mean follow-up of 16.3 months, we evaluated their outcomes. Significantly more patients with AMA experienced thigh pain (RR = 3.5, 95% CI: 1.67–7.33, p = 0.000), overall complications (RR = 4.47, 95% CI: 1.77–11.3, p = 0.000), and implant loosening (RR = 8.42, 95% CI: 2.63–26.95, p = 0.000). There were no definite cement related deaths in this series. There was no significant difference in mortality, walking status, and the number of revisions between the groups. We support the routine use of cemented hemiarthroplasty instead of the Austin Moore for treating elderlies with displaced intracapsular neck of femur fractures.

Risk factors for Clostridium difficile infection in HIV-infected patients.

Background:Clostridium difficile infection is a healthcare-associated infection resulting in significant morbidity. Although immunosuppression is associated with Clostridium difficile infection acquisition and adverse outcomes, the epidemiology of Clostridium difficile infection in HIV-infected patients has been little studied in the era of antiretroviral therapy. This study identifies the risk factors for acquisition of Clostridium difficile infection in HIV-infected patients.Methods:A retrospective, propensity score–matched case–control study design was employed, with patients selected from our institution’s outpatient HIV clinic. Clostridium difficile infection cases were defined as having positive stool testing plus an appropriate clinical presentation. The propensity score was generated via multiple logistic regression from year of HIV diagnosis, age at first contact, duration of follow-up, gender, and initial CD4 count.Results:The 46 cases included were matched to a total of 180 controls. Prior antibiotic treatment was a significant predictor of Clostridium difficile infection (odds ratio: 13, 95% confidence interval: 3.49–48.8, p < .001) as was number of hospital admissions in the preceding year (odds ratio: 4.02, confidence interval: 1.81–8.94, p < .001). Having both proton pump inhibitor use and CD4 count <200 cells/µL significantly increased odds of Clostridium difficile infection in the multivariable model (odds ratio: 15.17, confidence interval: 1.31–175.9, p = .021).Conclusion:As in the general population, frequent hospitalizations and exposure to antimicrobials are independent predictors of Clostridium difficile infection acquisition in patients with HIV. Additionally, low CD4 count and proton pump inhibitor use are new potentially modifiable variables that can be targeted for prevention of Clostridium difficile infection in future interventional studies.

Left Renal Vein Division During Open Surgery of Abdominal Aortic Disease: A Propensity Score-Matched Case–Control Study

To investigate the impact of left renal vein division (LRVD) on the postoperative renal function of abdominal aortic aneurysm (AAA) or aortic occlusive disease (AOD). Between January 2000 and January 2012, 238 patients, including 179 AAAs and 59 AODs underwent open surgery in our institution (patients who required suprarenal aortic clamping were excluded). 49 patients (38 AAAs, 11 AODs) required LRVD during the operation. Patients in the LRVD and non-LRVD groups were matched using propensity score method in a 1:2 ratio. Pre- and postoperative renal function, major complications, in-hospital mortality and long-term renal function were compared. Late survival rate was estimated using the Kaplan-Meier method. Overall, the LRVD group had a significantly higher male/female ratio (39/10 vs.122/67, p = .045), higher ruptured AAA ratio (36.7% vs. 20.1%, p = .014), higher American Society of Anesthesiologists (ASA) classification 3 (53.1% vs. 30.2%, p = .003), higher co-morbidities of coronary artery disease (51.0% vs. 33.3%, p = .022), higher preoperative shock (22.4% vs. 8.5%, p = .006) and longer operative time (164.2 ± 43 vs. 150.1 ± 41 min, p = .035). With propensity score matching (PSM), 48 patients in the LRVD group and 96 in the non-LRVD group were enrolled in this study. The baseline characteristics were well balanced in the groups (p < .05) after PSM. There were no statistically significant differences in preoperative glomerular filtration rate (GFR, expressed as mL/min/1.73 m(2)) (62.0 ± 13.1 vs. 62.9 ± 12.9, p = .695), and postoperative GFR on day 1 (60.3 ± 13.7 vs. 61.3 ± 13.1, p = .671), day 3 (54.6 ± 16.8 vs. 58.8 ± 14.3, p = .120), day 7 (62.1 ± 16.8 vs. 63.7 ± 13.4 p = .537) and in the long term (>12 months) (62.4 ± 14.0 vs. 64.7 ± 11.8 p = .302). There were no statistically significant differences in in-hospital mortality (6.3% vs. 9.2%, p = .522) and late survival rate estimated by the Kaplan-Meier method (p = .96). LRVD may be a safe maneuver during abdominal aortic surgery as it did not increase the risks of early or late mortality and morbidity.

A propensity score–matched case–control comparative study of laparoscopic and open extended (D2) lymph node dissection for distal gastric carcinoma

Technical proficiency at laparoscopic D2 lymph node dissection (LND) is essential for extending the use of laparoscopic surgery beyond the treatment of early gastric cancer (EGC). The aim of this study was to evaluate the technical and oncological feasibility of laparoscopic distal gastrectomy (LDG) with D2 LND for distal gastric cancer. Of 922 patients who underwent open or LDG with D2 LND for gastric carcinoma, 133 treated by LDG and 133 treated by open distal gastrectomy (ODG) were selected using the propensity score matching method. The short-term surgical outcomes and long-term survivals of these matched groups were compared. The two study groups were well matched with respect to age, sex, body mass index, comorbidity, ASA score, abdominal operation history, and tumor stage. The LDG group had a significantly longer mean operating time (227 vs. 161 min, p < 0.001) but showed significantly less intraoperative blood loss (149 vs. 189 ml, p = 0.007). Total numbers of collected lymph nodes were similar in the two groups. Postoperatively, no significant intergroup differences were found for hospital stay, morbidity, or mortality. Furthermore, overall survivals were similar in the two groups (p = 0.621). Multivariate analysis showed that male gender, age ≥70 years, and intraoperative blood loss of ≥200 ml were independent risk factors of postoperative morbidity. Laparoscopic D2 LND for distal gastric cancer is technically safe and feasible compared with ODG. A prospective randomized trial is warranted to evaluate long-term oncological outcomes in advanced gastric carcinoma.

Predicting the "revolving door" phenomenon among patients with schizophrenic, schizoaffective, and affective disorders

A subpopulation of chronically mentally ill patients, sometimes referred to as "revolving door" patients, are frequently readmitted to psychiatric units. This study examined the relationships among demographic features, diagnostic characteristics, and frequency of hospitalization of patients from four state hospitals. Two semistructured, standardized instruments, the Schedule for Affective Disorders and Schizophrenia and a life events history, were administered to 135 inpatients who met the Research Diagnostic Criteria for schizophrenia (N = 56), schizoaffective disorder (N = 33), unipolar major depressive disorder (N = 23), and bipolar disorder (N = 23). Criminal history was assessed by arrest records. The main outcome measure was the number of hospitalizations. Chi-square and trend test analyses indicated that substance abuse and noncompliance with medication regimens were significantly associated with higher frequencies of hospitalization. A multiple regression model, which included alcohol/drug problems, medication noncompliance, and six sociodemographic and diagnostic variables (age, gender, race, marital status, years of education, and diagnosis) accounted for a significant proportion of the ability to predict frequency of hospitalization. Half of this predictability was due to the relationship of substance abuse and medication noncompliance with number of hospitalizations. Alcohol/drug problems and noncompliance with medication were the most important factors related to frequency of hospitalization. Preventing these behaviors through patient education may reduce rehospitalization rates.