Association between Serum IGF-I levels and Postoperative Delirium in Elderly Subjects Undergoing Elective Knee Arthroplasty.

Evidence is mixed for an association between serum insulin-like growth factor-I (IGF-I) levels and postoperative delirium (POD). The current study assessed preoperative serum IGF-I levels as a predictor of incident delirium in non-demented elderly elective knee arthroplasty patients. Preoperative serum levels of total IGF-I were measured using a commercially available Human IGF-I ELISA kit. POD incidence and severity were determined using DSM-IV criteria and the Delirium Rating Scale-Revised-98 (DRS-R98), respectively. Median IGF-I levels in delirious (62.6 ng/ml) and non-delirious groups (65.9 ng/ml) were not significantly different (p = 0.141). The ratio (95% CI) of geometric means, D/ND, was 0.86 (0.70, 1.06). The Hodges-Lehmann median difference estimate was 7.23 ng/mL with 95% confidence interval (-2.32, 19.9). In multivariate logistic regression analysis IGF-I level was not a significant predictor of incident POD after correcting for medical comorbidities. IGF-I levels did not correlate with DRS-R98 scores for delirium severity. In conclusion, we report no evidence of association between serum IGF-I levels and incidence of POD, although the sample size was inadequate for a conclusive study. Further efforts to investigate IGF-I as a delirium risk factor in elderly should address comorbidities and confounders that influence IGF-I levels.

Development and implementation of a formalized geriatric surgery curriculum for general surgery residents.

Despite the growth of the elderly population, most surgical training programs lack formalized geriatric education. The authors' aim was to implement a formalized geriatric surgery curriculum at an academic medical center. Surgery residents were surveyed on attitudes toward the care of elderly patients and the importance of various geriatric topics to daily practice. A curriculum consisting of 16 didactic sessions was created with faculty experts moderating. After curriculum completion, residents were surveyed to assess curriculum impact. Residents expressed increased comfort in accessing community resources. A greater percentage of residents recognized the significance of delirium and acute renal failure in elderly patients. Implementing a geriatric surgery curriculum geared toward surgery residents is feasible and can increase resident comfort with multidisciplinary care and recognition of clinical conditions pertinent to elderly surgical patients. This initiative also provided valuable experience for geriatric surgery curriculum development.

Comparison of outcomes and the use of multimodality therapy in young and elderly people undergoing surgical resection of pancreatic cancer.

OBJECTIVES: To compare outcomes and the use of multimodality therapy in young and elderly people with pancreatic cancer undergoing surgical resection. DESIGN: Retrospective, single-institution study. SETTING: National Cancer Institute/National Comprehensive Cancer Network cancer center. PARTICIPANTS: Two hundred three individuals who underwent pancreaticoduodenectomy for pancreatic adenocarcinoma at Duke University Medical Center comprised the study population. Participants were divided into three groups based on age (<65, n = 97; 65-74, n = 74; ≥75, N = 32). MEASUREMENTS: Perioperative outcomes, the use of multimodality therapy, and overall survival of the different age groups were compared. RESULTS: Similar rates of perioperative mortality and morbidity were observed in all age groups, but elderly adults were more likely to be discharged to a rehabilitation or skilled nursing facility. A similar proportion of participants received neoadjuvant therapy, but a smaller proportion of elderly participants received adjuvant therapy. Overall survival was similar between the age groups. Predictors of poorer overall survival included coronary artery disease, positive resection margin, and less-differentiated tumor histology. Treatment with neoadjuvant and adjuvant therapy were predictors of better overall survival. CONCLUSION: Carefully selected elderly individuals experience similar perioperative outcomes and overall survival to those of younger individuals after resection of pancreatic cancer. There appears to be a significant disparity in the use of adjuvant therapy between young and elderly individuals.

Differential gene expression of interleukin-1 receptor associated kinase-1 and interleukin-1 receptor associated kinase-M in peripheral blood mononuclear cells of young and aged rats following preconditioning with endotoxin.

The IL-1 receptor-associated kinase 1 (IRAK-1) and IRAK-M are key signaling molecules in cellular responses to endotoxin initiated through the Toll-like receptors (TLRs). The aim of this study was to evaluate the effect of age on the modulation of TLRs and IRAK-1 and IRAK-M in peripheral blood mononuclear cells (PBMCs) exposed in vitro to endotoxin under conditions that could induce endotoxin tolerance. Peripheral blood mononuclear cells obtained from young (4- to 6-month-old) and aged (24- to 26-month-old) Brown Norway rats were treated with high-dose LPS, with or without priming with low-dose LPS. In comparison with younger rats, the intensity of TLR-4 expression was persistently high in monocytes from aged rats after stimulation with LPS and was not decreased by priming with low-dose LPS (P < 0.05). Messenger RNA (mRNA) for TLR-4 in PBMCs from aged rats did not show any decrease after priming with low-dose LPS as seen in PBMCs from young rats at 24 h (P = 0.01) after restimulation. In PBMCs from young rats, but not aged rats, preconditioning with low-dose LPS and subsequent stimulation with high-dose LPS resulted in markedly decreased IRAK-1 protein (P = 0.02) and decreased mRNA for IRAK-1 (P < 0.05). In contrast, PBMCs from aged rats treated in this manner continued to express measurable levels of IRAK-1 protein. Preconditioning with low-dose LPS caused an increase in both IRAK-M protein and mRNA (P = 0.05) after stimulation with high-dose LPS only in cells from young rats. These phenotypic characteristics of PBMCs from aged rats can interfere with their ability to develop tolerance to endotoxin.