Biomedical subjects

Sunni A Barnes

Publications and source records attributed to Sunni A Barnes.

10 recordsLinked to original sources

PubMed2006

Completely resected N1 non-small cell lung cancer: factors affecting recurrence and long-term survival.

OBJECTIVE: N1 disease in non-small cell lung cancer represents a heterogeneous patient subgroup with a 5-year survival of approximately 40%. Few reports have evaluated the correlation between N1 disease and tumor recurrence or which subgroup of patients would most benefit from adjuvant chemotherapy. METHODS: From 1997 through 2002, all patients with pathologic T1-4 N1 M0 non-small cell lung cancer who had a complete resection with systematic mediastinal lymphadenectomy were retrospectively analyzed and evaluated for factors associated with recurrence and long-term survival. RESULTS: One hundred eighty patients with N1 disease were evaluated. Sixty-six (37%) patients had either locoregional recurrence (n = 39 [22%]), distant metastasis (n = 41 [23%]), or both during follow-up. Univariate analysis demonstrated that visceral pleural invasion and age were associated with locoregional recurrence, whereas visceral pleural invasion, distinct N1 metastasis (as opposed to direct N1 invasion by the primary tumor), and multistation lymph node involvement were associated with distant metastasis (P < .05). Multivariable analysis demonstrated that visceral pleural invasion, multistation N1 involvement, and distinct N1 metastasis were the only independent predisposing factors for locoregional recurrence and distant metastasis. Overall 5-year survival was 42.5%. Survival was significantly decreased by advanced pathologic T classification (P = .015), visceral pleural invasion (P < .0001), and higher tumor grade (P = .014). CONCLUSIONS: In patients with N1-positive non-small cell lung cancer, visceral pleural invasion, multistation N1 disease, and distinct N1 metastasis are independent predictors of subsequent locoregional recurrence and distant metastasis. Advanced T classification, visceral pleural invasion, and higher tumor grade were predictors of poor survival. These patients represent a subgroup of patients with N1 disease who might benefit from additional therapy, including adjuvant chemotherapy.

Adult↗

PubMed2006

Multiple imputation techniques in small sample clinical trials.

Clinical trials allow researchers to draw conclusions about the effectiveness of a treatment. However, the statistical analysis used to draw these conclusions will inevitably be complicated by the common problem of attrition. Resorting to ad hoc methods such as case deletion or mean imputation can lead to biased results, especially if the amount of missing data is high. Multiple imputation, on the other hand, provides the researcher with an approximate solution that can be generalized to a number of different data sets and statistical problems. Multiple imputation is known to be statistically valid when n is large. However, questions still remain about the validity of multiple imputation for small samples in clinical trials. In this paper we investigate the small-sample performance of several multiple imputation methods, as well as the last observation carried forward method.

Bayes Theorem↗

PubMed2006

A single-center experience with inflammatory breast cancer, 1985-2003.

HYPOTHESIS: "Up-front" surgery improves survival in inflammatory breast cancer (IBC). DESIGN: Retrospective cohort, 1985-2003. SETTING: Tertiary referral center. PATIENTS: Consecutive patients with a primary occurrence of IBC. MAIN OUTCOME MEASURES: All-cause and disease-free survival. RESULTS: One-hundred fifty-six patients were identified with IBC; 28 patients with metastatic disease were excluded from further analysis. The mean age of the remaining 128 patients was 53 years; 57% of women were postmenopausal. One hundred twenty-two patients had clinically apparent IBC. Tumors were palpable in 83 patients (mean diameter, 9.1 cm). Neoadjuvant chemotherapy was the initial therapy in 106 patients, while surgery was the initial therapy in 22 patients. The overall median survival was 37 months, with a median disease-free interval of 23 months. The 5-year survival was 42%, with a disease-free survival of 21%. Univariate analysis of recurrence identified previous hormone therapy (relative risk [RR], 0.50; P = .03), menopause (RR, 0.55; P = .01), and palpable adenopathy (RR, 1.57; P = .04) as significant factors. Univariate survival analysis highlighted previous hormone therapy (RR, 0.48; P = .04), radiotherapy (RR, 0.39; P = .02), sequence of therapy (P = .001), family history (RR, 0.47; P = .01), and palpable adenopathy (RR, 2.22; P<.001) as being important. Multivariate analysis of recurrence identified menopausal status as the key factor. Adenopathy at the initial examination was associated with decreased length of survival, while radiotherapy was associated with better survival. CONCLUSIONS: Survival from IBC remains poor. Although adenopathy and radiotherapy affected survival by multivariate analysis, the sequence of therapy was not associated with improved outcome.

Adenocarcinoma↗

PubMed2006

Beta-2 adrenergic receptor polymorphisms and the forearm blood flow response to mental stress.

Circulating epinephrine plays an important role in skeletal muscle vasodilation during mental stress. Normotensive adults homozygous for glycine (Gly) of the Arg16/Gly beta2-adrenergic receptor polymorphism have a greater forearm beta2-receptor mediated vasodilation and a higher cardiac output response to isometric handgrip than arginine (Arg) homozygotes. To test the hypothesis that the Arg16/Gly beta2-adrenergic receptor polymorphism affects the forearm blood flow (FBF) and hemodynamic response to mental stress, and whether venous catecholamine concentrations predicted these responses, we measured venous epinephrine, norepinephrine, heart rate (HR), arterial pressure (Finapres), and FBF during mental stress in healthy subjects homozygous for Gly16 (n = 30; mean age +/- SE: 30 +/- 1.2, 13 women) and Arg16 (n = 17, age 30 +/- 1.6, 11 women). Resting HR, blood pressure, and FBF responses to mental stress were similar between genotype groups. There were positive correlations between epinephrine and peak FBF (r = 0.694, P < 0.001), peak forearm vascular conductance (r = 0.677, P < 0.001) and the change in epinephrine to the change in HR (r = 0.456, P = 0.002) in all subjects. These correlations were not significantly different in the Gly16 and Arg16 groups. We conclude that venous epinephrine predicts the FBF response to mental stress, and the increase in epinephrine is also correlated with the increase in HR. Furthermore, the Arg16/Gly beta2-receptor polymorphism has no significant influence on the FBF or cardiovascular responses to mental stress.

Adult↗

PubMed2006

Prognostic implications of preoperative atrial fibrillation in patients undergoing aortic valve replacement: is there an argument for concomitant arrhythmia surgery?

BACKGROUND: The prognostic significance of preoperative atrial fibrillation (AF) at the time of aortic valve replacement is unknown, as is the potential role for concomitant arrhythmia surgery. METHODS: We performed a cohort comparison of patients with preoperative AF (n = 129) and preoperative sinus rhythm (SR, n = 252) undergoing aortic valve surgery between 1993 and 2002; patients were matched for age, gender, and left ventricular ejection fraction. Follow-up (mean interval, 4.5 years) was 98% complete. Primary endpoints were late cardiac and all-cause mortality, as well as major adverse cardiac or cerebrovascular event. RESULTS: Patients with preoperative AF presented with more severe congestive heart failure (p = 0.03) and more often had significant tricuspid regurgitation (p = 0.01) preoperatively. They also had worse late survival (risk ratio [RR] for death = 1.5, p = 0.03) with 1-, 5-, and 7-year survival rates substantially reduced at 94%, 87%, and 50%, respectively, for those in AF versus 98%, 90%, and 61% for patients in sinus rhythm preoperatively. Individuals in AF had a greater probability of subsequent rhythm-related intervention (RR = 4.7, p = 0.0002), and more frequently developed congestive heart failure (25% vs 10%, p = 0.005) and stroke (16% vs 5%, p = 0.005). By multivariable analysis, preoperative AF was an independent predictor of late adverse cardiac and cerebrovascular events, but not late death. CONCLUSIONS: Performance of concomitant arrhythmia surgery in patients undergoing aortic valve surgery may reduce late morbidity; however, its potential impact on late mortality in this high-risk subset of patients remains unclear.

Aged↗

PubMed2006

Safety, feasibility, and short-term outcomes of laparoscopic ileal-pouch-anal anastomosis: a single institutional case-matched experience.

OBJECTIVE: To compare safety and short-term outcomes of 100 laparoscopic ileal pouch-anal anastomosis (IPAA) versus 200 conventional open IPAA patients. SUMMARY BACKGROUND DATA: Outcomes of laparoscopic IPAA (LAP-IPAA) have been incompletely characterized. Previous reports are characterized by small numbers of patients and rarely include case-matched or randomized trial methodology. This report describes 100 LAP-IPAA patients case matched to 200 open IPAA patients. METHODS: Between 1998 and 2004, 100 consecutive LAP-IPAA patients (75 laparoscopic assisted, 25 hand assisted) were identified and case matched to 200 open IPAA control patients by age, operation, gender, date of operation, and body mass index. Operative and postoperative outcomes at 90 days were compared. RESULTS: A total of 300 patients (180 female) with a median age of 32 years (range, 17-66 years), and a median body mass index of 23 kg/m (range, 16-34 kg/m) underwent IPAA (100 LAP-IPAA, 200 open IPAA). Diagnosis (chronic ulcerative colitis 97%, familial adenomatous polyposis 3%) and previous operative history were equivalent between groups. One intraoperative complication occurred in each group. Overall, the laparoscopic conversion rate was 6%. Median operative time was longer for the LAP-IPAA group (333 minutes versus 230 minutes, P < 0.0001). LAP-IPAA patients had shorter median time to regular diet (3 versus 5 days), time to ileostomy output (2 versus 3 days), length of stay (4 versus 7 days), and decreased IV narcotic use (all P < 0.05. Postoperative morbidity was equivalent (LAP-IPAA = 33%, open IPAA = 37%), mortality was nil, and readmission rates were equal (LAP-IPAA = 21%, open IPAA = 22%). Reoperation was required in 3% of LAP-IPAA and 6.5% of open IPAA patients (P < 0.2) during the first 3 months. CONCLUSION: LAP-IPAA is equivalent to open IPAA in terms of safety and feasibility. In addition, LAP-IPAA provides significant improvements in short-term recovery outcomes.

Adenomatous Polyposis Coli↗

PubMed2006

A comparison of self-reported use of behavioral health services with Medicaid agency records in Minnesota.

OBJECTIVE: This study examined how well recipients of psychiatric or substance abuse services self-report their care. METHODS: Self-reported use of behavioral health services, as reported by 1,012 respondents to a survey mailed to Minnesota Medicaid managed care enrollees receiving services with a behavioral health diagnosis other than severe mental illness in 2000, was compared with Medicaid agency records. RESULTS: Overall, 15 percent of respondents said they had not received services, although administrative data indicated otherwise. In bivariate analyses, failure to report treatment was associated with gender, age, education, and diagnosis but not with race or ethnicity or with residence. The effects of gender and diagnosis were insignificant after analyses controlled for age and education. CONCLUSIONS: Self-reports of behavioral health service use are a relatively accurate method of obtaining information on use. The finding that underreporting of receipt of behavioral health services was not random suggests that reporting errors could introduce bias when comparing groups that differ on age or education.

Adolescent↗

PubMed2006

Patient and physician-assessed shoulder function after arthroplasty.

BACKGROUND: We found no information in the literature regarding the relationship between patient and physician-derived outcome assessments with a shoulder questionnaire. In this study, we examined a group of patients who were assessed with patient and physician-administered questionnaires following shoulder arthroplasty. METHODS: From August 2003 to February 2004, sixty-seven consecutive patients who had been followed for a minimum of six months after shoulder arthroplasty were evaluated with a self-administered and an identical physician-directed shoulder questionnaire that assessed clinical and functional outcomes at the time of routine follow-up. An assessment of the agreement between physicians and patients as well as the factors that affected agreement was performed. RESULTS: The intraclass correlation indicated almost perfect physician-patient agreement (>0.80) on items related to overall pain, pain at night, pain with activity, stability, and active elevation and substantial agreement (intraclass correlation, 0.66 and 0.69) between the physician and patient assessments of pain without activity and strength. While the differences were small, on the average physician ratings for pain were lower (indicating less pain) than patient ratings for pain, physicians rated stability and strength as being closer to normal, and they reported less active elevation. There was substantial agreement between the physician and patient assessments of outcome with the modified Neer system (intraclass correlation = 0.75), with 87% agreement if excellent and satisfactory outcomes were combined. CONCLUSIONS: A patient-derived questionnaire can provide a high level of agreement with surgeon assessments of outcome following shoulder surgery. Patient-administered methods should continue to be evaluated as a means of assessment of these patients.

Adult↗

PubMed2005

Arg16/Gly beta2-adrenergic receptor polymorphism alters the cardiac output response to isometric exercise.

Normotensive adults homozygous for glycine (Gly) of the Arg16/Gly beta2-adrenergic-receptor polymorphism have 1) greater forearm beta2-receptor mediated vasodilation and 2) a higher heart rate (HR) response to isometric handgrip than arginine (Arg) homozygotes. To test the hypothesis that the higher HR response in Gly16 subjects serves to maintain the pressor response [increased cardiac output (CO)] in the setting of augmented peripheral vasodilation to endogenous catecholamines, we measured continuous HR (ECG), arterial pressure (Finapres), and CO (transthoracic echocardiography) during isometric, 40% submaximal handgrip to fatigue in healthy subjects homozygous for Gly (n = 30; mean age +/- SE: 30 +/- 1.2, 13 women) and Arg (n = 17, age 30 +/- 1.6, 11 women). Resting data were similar between groups. Handgrip produced similar increases in arterial pressure and venous norepinephrine and epinephrine concentrations; however, HR increased more in the Gly group (60.1 +/- 4.3% increase from baseline vs. 45.5 +/- 3.9%, P = 0.03), and this caused CO to be higher (Gly: 7.6 +/- 0.3 l/m vs. Arg: 6.5 +/- 0.3 l/m, P = 0.03), whereas the decrease in systemic vascular resistance in the Gly group did not reach significance (P = 0.09). We conclude that Gly16 homozygotes generate a higher CO to maintain the pressor response to handgrip. The influence of polymorphic variants in the beta2-adrenergic receptor gene on the cardiovascular response to sympathoexcitation may have important implications in the development of hypertension and heart failure.

Adult↗

PubMed2005

Adenocarcinomas of the jejunum and ileum: a 25-year experience.

Adenocarcinomas of the jejunum and ileum are rare gastrointestinal malignancies. Because few large published experiences exist, we reviewed patients with jejunal and ileal adenocarcinoma treated at our institution over the last 25 years. Between January 1976 and December 2001, 77 patients had an operation for a jejunal or ileal adenocarcinoma. Records were retrospectively reviewed for patient, tumor, and treatment variables. Factors affecting disease recurrence and patient survival were investigated. Fifty-two of the adenocarcinomas (67%) occurred in the jejunum and 25 occurred in the ileum (33%). Mean patient age was 63 +/- 14 years. Segmental bowel resection was performed in 50 patients (65%) with curative intent. Palliative operative procedures including resection or bypass were performed in 27 patients (35%). One (1%) patient had stage I, 18 (23%) stage II, 19 (25%) stage III, and 39 (51%) stage IV adenocarcinoma at diagnosis. Postoperatively, 12 patients had palliative and 18 adjuvant chemotherapy (n = 30), radiation therapy (n = 1), or combination treatment (n = 7). Median patient survival was 19 months. Sixty-six percent of patients who had a curative operation had a tumor relapse. Tumor stage had a highly significant effect (P < 0.0001) on median survival (72 months for stage I and II, 30 months for stage III, and 9 months for stage IV disease). In multivariate analysis of patients having curative treatment, tumor recurrence (P < 0.0001), stage (P < 0.0002), and weight loss (P < 0.001) were significant negative prognostic indicators. Most patients with adenocarcinoma of the jejunum or ileum present with advanced disease. Tumor stage, disease recurrence, and weight loss predicted patient outcome following a curative operation. Early recognition of these tumors requires a high index of suspicion.

Adenocarcinoma↗