Preoperative CSF Melatonin Concentrations and the Occurrence of Delirium in Older Hip Fracture Patients:A Preliminary Study

BACKGROUND: Delirium is characterized by disturbances in circadian rhythm. Melatonin regulates our circadian rhythm. Our aim was to compare preoperative cerebrospinal fluid (CSF) melatonin levels in patients with and without postoperative delirium. METHODS: Prospective cohort study with hip fracture patients ≥ 65 years who were acutely admitted to the hospital for surgical treatment and received spinal anaesthesia. CSF was collected after cannulation, before administering anaesthetics. Melatonin was measured by radioimmunoassay (RIA). Data on delirium was obtained from medical and nursing records. Nurses screened every shift for delirium using the Delirium Observation Screening Scale (DOSS). If the DOSS was ≥3, a psychiatrist was consulted to diagnose possible delirium using the DSM-IV criteria. At admission, demographic data, medical history, and information on functional and cognitive status was obtained. RESULTS: Seventy-six patients met the inclusion criteria. Sixty patients were included in the analysis. Main reasons for exclusion were technical difficulties, insufficient CSF or exogenous melatonin use. Thirteen patients (21.7%) experienced delirium during hospitalisation. Baseline characteristics did not differ between patients with and without postoperative delirium. In patients with and without postoperative delirium melatonin levels were 12.88 pg/ml (SD 6.3) and 11.72 pg/ml (SD 4.5) respectively, p-value 0.47. No differences between patients with and without delirium were found in mean melatonin levels in analyses stratified for cognitive impairment or age. CONCLUSION: Preoperative CSF melatonin levels did not differ between patients with and without postoperative delirium. This suggests that, if disturbances in melatonin secretion occur, these might occur after surgery due to postoperative inflammation

Preoperative CSF melatonin levels in pg/ml in patients with and without postoperative delirium.

<p>Preoperative CSF melatonin levels in pg/ml in patients with and without postoperative delirium.</p

Characteristics of hip fracture patients with and without postoperative delirium.

<p>Characteristics are shown as number of patients (%) unless stated otherwise.</p

Clinical verification of 18F-DCFPyL PET-detected lesions in patients with biochemically recurrent prostate cancer

PURPOSE: Radiolabeled Prostate-Specific Membrane Antigen (PSMA) PET/CT is the current standard-of-care for lesion detection in patients with biochemically recurrent (BCR) prostate cancer (PCa). However, rigorous verification of detected lesions is not always performed in routine clinical practice. To aid future 18F-radiolabeled PSMA PET/CT interpretation, we aimed to identify clinical/imaging characteristics that increase the likelihood that a PSMA-avid lesion is malignant. MATERIALS AND METHODS: 262 patients with BCR, who underwent 18F-DCFPyL PSMA PET/CT, were retrospectively analyzed. The malignant nature of 18F-DCFPyL PET-detected lesions was verified through any of the following metrics: (1) positive histopathological examination; (2) additional positive imaging; (3) a ≥50% decrease in Prostate-Specific Antigen (PSA) following irradiation of the lesion(s). RESULTS: In 226/262 PET scans (86.3%) at least one lesion suspicious for recurrent PCa was detected ('positive scan'). In 84/226 positive scans (37.2%), at least one independent verification metric was available. PSMA PET-detected lesions were most often confirmed to be malignant (PCa) in the presence of a CT-substrate (96.5% vs. 55.6% without CT-substrate), with SUVpeak ≥3.5 (91.4% vs. 60.0% with SUVpeak2 PET-positive lesions (94.1% vs. 64.2% in patients with 1-2 PET-positive lesions; p<0.001-0.03). CONCLUSIONS: In this study, the clinical verification of 18F-DCFPyL PET-positive lesions in patients with BCR was performed. Diagnostic certainty of PET-detected lesions increases in the presence of characteristic abnormalities on CT, when SUVpeak is ≥3.5, when PSA-levels exceed 2.0 ng/mL or in patients with more than two PET-positive lesions