Longitudinal Cognitive Decline in Patients With Mild Cognitive Impairment or Dementia Due to Alzheimer's Disease

Sensitive cognitive assessments accurately detect and track cognitive decline in Alzheimer's disease. The Cogstate battery was used to measure cognitive change in cognitively normal participants and in individuals with mild cognitive impairment and mild Alzheimer's disease enrolled in the Australian Imaging, Biomarker and Lifestyle Rate of Change Substudy. Over 18 months, verbal episodic memory performance declined for mild cognitive impairment and mild Alzeheimer's disease groups when compared to cognitively normal participants. Frequent assessments of episodic memory may facilitate early detection of cognitive decline due to Alzheimer's disease.

Efficacy and safety of ivermectin for the treatment of COVID-19: a systematic review and meta-analysis

BACKGROUND

Ivermectin became a popular choice for COVID-19 treatment among clinicians and the public following encouraging results from pre-print trials and in vitro studies. Early reviews recommended the use of ivermectin based largely on non-peer-reviewed evidence, which may not be robust. This systematic review and meta-analysis assessed the efficacy and safety of ivermectin for treating COVID-19 based on peer-reviewed randomized controlled trials (RCTs) and observational studies (OSs).

METHODS

MEDLINE, EMBASE and PubMed were searched from 1 January 2020 to 1 September 2021 for relevant studies. Outcomes included time to viral clearance, duration of hospitalization, mortality, incidence of mechanical ventilation and incidence of adverse events. RoB2 and ROBINS-I were used to assess risk of bias. Random-effects meta-analyses were conducted. GRADE was used to evaluate quality of evidence.

RESULTS

Three OSs and 14 RCTs were included in the review. Most RCTs were rated as having some concerns in regards to risk of bias, while OSs were mainly rated as having a moderate risk of bias. Based on meta-analysis of RCTs, the use of ivermectin was not associated with reduction in time to viral clearance, duration of hospitalization, incidence of mortality and incidence of mechanical ventilation. Ivermectin did not significantly increase incidence of adverse events. Meta-analysis of OSs agrees with findings from RCT studies.

CONCLUSIONS

Based on very low to moderate quality of evidence, ivermectin was not efficacious at managing COVID-19. Its safety profile permits its use in trial settings to further clarify its role in COVID-19 treatment.

PROTOCOL REGISTRATION

The review was prospectively registered in PROSPERO (CRD42021275302).

Evidence for the integration of total and free testosterone levels in the management of prostate cancer

OBJECTIVE

To comprehensively assess total and calculated free testosterone levels in a consecutive group of patients with prostate cancer (PCa) and any potential impact on disease aggressiveness and recurrence outcomes.

PARTICIPANTS AND METHODS

The study included a single-centre prospective cohort of 882 patients presenting for radical prostatectomy from 2009 to 2018. Data on total testosterone (TT), sex hormone-binding globulin (SHBG), and calculated free testosterone (cFT) were prospectively collected. Stepwise logistic regression models were used to assess correlations of TT and cFT with pathological Gleason Grade Group (GGG), extraprostatic extension (EPE), seminal vesicle invasion (SVI) and biochemical recurrence (BCR).

RESULTS

Total testosterone remained nearly constant across decades (40s-80s): 0.09 decrease/year (R = 0.02), while SHBG increased 0.87/year (R = 0.32) and cFT decreased 0.08/year (R = -0.02). Low cFT of <5.5 independently predicted: very-high-risk GGG (odds ratio [OR] 0.435, 95% confidence interval [CI] 0.846-0.994; P = 0.036), EPE (OR 0.557, 95% CI 0.810-0.987; P = 0.011), SVI (OR 0.396, 95% CI 0.798-1.038; P = 0.059), and BCR within 1 year after robot-assisted radical prostatectomy (OR 0.638, 95% CI 0.971-3.512, P = 0.046). TT was not a predictor.

CONCLUSION

In contrast to popular belief, testosterone remained stable in men aged 40-80 years, whereas free testosterone decreased by 2-3%/year. Low cFT was an independent predictor of very-high-risk PCa and BCR.

Retrospective Concomitant Nonrandomized Comparison of "Touch" Cautery Versus Athermal Dissection of the Prostatic Vascular Pedicles and Neurovascular Bundles During Robot-assisted Radical Prostatectomy

BACKGROUND

During robotic-assisted radical prostatectomy (RARP), the use of electrocautery near the neurovascular bundles (NVBs) frequently results in thermal injury to the cavernous nerves. The cut and "touch" monopolar cautery technique has been suggested to reduce desiccating thermal injury caused by bipolar energy when vessels are sealed.

OBJECTIVE

To compare potency outcomes between an athermal technique (AT) and touch cautery (TC) to transect the prostatic vascular pedicles (PVPs) and dissect the NVBs.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective concomitant nonrandomized study of AT versus TC was performed in 733 men. A total of 323 undergoing AT had "thin" pedicles, easily suitable for suture ligation. TC was based on "thick" pedicles (n = 230) difficult to suture ligate. Men were excluded for an International Index of Erectile Function (IIEF-5) score of <15 or adjuvant therapies (n = 180).

SURGICAL PROCEDURE

Single-surgeon RARP.

MEASUREMENTS

Patient-reported outcomes with erectile function (EF) recovery defined as two affirmative answers to erections sufficient for intercourse (ESI; "are erections firm enough for penetration?" and "are the erections satisfactory?"), IIEF-5 scores 15-25, and a novel percent fullness score comparing pre- versus postoperative erection fullness. Logistic regression models assessed the correlation between cautery technique, covariates, and EF recovery.

RESULTS AND LIMITATIONS

In an unadjusted analysis, preoperative IIEF-5, age, body mass index (BMI), and prostate weight were significant predictors of potency recovery. Follow-up was similar (AT 52.7 mo vs TC 54.6 mo, p = 0.534). In logistic regression, preoperative IIEF-5, age, and BMI were significant predictors of EF recovery, defined as IIEF-5 scores 15-25, ESI, and percent fullness >75%. Results were similar when IIEF-5 and percent fullness were assessed continuously.

CONCLUSIONS

During transection of the PVPs and dissection of the NVBs, TC did not impact EF recovery significantly, compared with an AT.

PATIENT SUMMARY

Electrocautery can be applied safely, with similar outcomes to those of an athermal technique.

Enhancing titre and production stability of paenibacillin from Paenibacillus polymyxa by sequential drug resistance screening

AIMS

Paenibacillin is a naturally biosynthesized antimicrobial lantibiotic peptide which is produced by wild-type Paenibacillus polymyxa OSY-DF in low but detectable levels. The aim was to increase paenibacillin titre and production consistency through sequential drug resistance screening.

METHODS AND RESULTS

Spontaneous mutants of P. polymyxa OSY-DF were isolated by subjecting the bacterium to two rounds of screening for resistance to rifampicin, which targets RNA polymerase, and gentamicin, which targets ribosomes. Changes in antimicrobial production of the mutants were monitored using a bioassay method. A spontaneous mutant, P. polymyxa OSY-EC, capable of producing high paenibacillin titre, was selected and compared phenotypically to the wild-type strain. The mutant was found to produce paenibacillin at five-fold higher titre than the wild type. The mutant constantly produced paenibacillin while the wild type produced the antimicrobial agent variably. Fourier transformation mid-infrared spectroscopy revealed an interclass distance of 6·4 between the wild type and the mutant strain, suggesting significant phenotypic change during the mutation.

CONCLUSIONS

P. polymyxa OSY-EC, a spontaneous mutant capable of consistent production of high paenibacillin titre, was isolated from the wild type after sequential screening on rationally selected antibiotics.

SIGNIFICANCE AND IMPACT OF THE STUDY

The study will help make paenibacillin available for large-scale testing by interested researchers and industries seeking applications that improve food safety and quality.

Active surveillance of postradical prostatectomy biochemical recurrence: Long-term assessment of outcomes

5081

Background: Biochemical recurrence (BCR) following radical prostatectomy (RP) is an unreliable predictor of distant metastatic progression/prostate cancer death, resulting in potential complications & expenses of overtreatment. Little has been published on management decisions & outcomes of active surveillance (AS). We characterize our long term experience with AS following post-RP BCR without radiation/androgen deprivation therapy. Methods: From June 2002 - September 2019, 1865 men underwent RP. 406 experienced BCR; of these, 138 (34%) were observed without treatment intervention. BCR defined as PSA>0.2 ng/dl, x2. PSAs checked every 1-3 months and entered into a PSADT graph. Men were considered to be formally AS after 3+ years of increasing DT following RP. Men with decreasing DT were treated and censored. Results: The table depicts demographics of the AS patients; median follow-up was 7.3 years (IQR: 4.6-10.6) post-RP. Of patients on AS, average age was 63.7 +/- 7.2 years and 86%, 48%, 40%, 51% and 14% were GG 1 through 5, respectively. Current DT of AS patients averages 20 months, with 0% PCSM. Only 10% of patients with decreasing DT began treatment after average 4 years following BCR. Conclusions: Of 406 patients experiencing post-RP BCR, 34% of patients are effectively managed with AS, with 0% PCSM across all GG. Presently 69 (50%) AS men have been under observation for 7.3 to 18 years. This suggests that significant portion of patients display benign recurrence, characterized by increasing DT following BCR and can be managed safely with observation alone.[Table: see text]

Post radical prostatectomy prostate-specific antigen doubling-time kinetics: Observations of increasing versus decreasing doubling times

e17002

Background: Biochemical recurrence (BCR) following radical prostatectomy (RP) is an unreliable predictor of distant metastatic progression or prostate cancer (PC) death, consequently resulting in overtreatment. Further, little has been published about active surveillance (AS) specific management recommendations. Herein, we validate the practicality of using the kinetics (change) of PSA doubling time (PSADT) to direct continued observation versus intervention. Methods: In a retrospective cohort analysis of 406 men with BCR (defined as adjuvant therapy or PSA > 0.2 ng/dl, x2), 284 men were monitored post RP with PSADT graphs for all patients, and the PSADT was characterized as increasing vs decreasing. Receiver-operator characteristic (ROC) curves were generated to assess the sensitivity/specificity/positive predictive value/negative predictive value of PSADT progression on treatment and prostate cancer specific mortality at 10 years post-RARP, respectively. Results: The median follow-up was 7.6 (IQR: 4.6-10.6) years. Of 284 men, 109 (38%) and 175 (62%) were in the no treatment versus treatment groups, respectively. 87% of men receiving treatment had a decreasing PSADT and 100% men with PCSM had a decreasing PSADT. ROC analysis showed 0.870 sensitivity and 1.0 specificity when predicting secondary treatment (AUC = 0.935) and 0.857 sensitivity and 0.50 specificity when predicting PCSM (AUC = 0.679). Conclusions: A decreasing PSADT is a sensitive and specific metric for predicting the need for secondary intervention. We also found all men who died of PC had a decreasing PSADT. Lastly an increasing DT predicts a benign course without need for treatment. The current findings suggest that the kinetics of PSADT, increasing versus decreasing, is an accurate metric for the need of treatment. A direct comparison between PSADT kinetics and PSADT is needed.

Protective Effects of Metformin Against Biochemical Failure Following Radical Prostatectomy or Radiation Therapy in Localized Prostate Cancer

OBJECTIVE

To assess the impact of metformin on biochemical failure (BF) in localized prostate cancers (PC) treated with radical prostatectomy or radiation therapy.

MATERIALS AND METHODS

About 1449 patients undergoing radical prostatectomy (n = 1338, 92.3%) or radiation therapy (n = 108, 7.5%) for localized PC between July 2007 and January 2020 were evaluated for metformin use, demographic/oncologic characteristics, and biochemical outcomes. Androgen deprivation therapy was utilized per NCCN guidelines. BF rates were assessed overall and at 1, 3, and 5 years. Time to BF was estimated via Kaplan-Meier; logistic regression and Cox proportionate hazards models were generated to adjust for significant differences.

RESULTS

Of 1449 patients, 148 (10.2%) utilized metformin at time of diagnosis, while 1,301 (89.8%) did not. Patients on metformin were significantly older, had higher body mass indexes, and more aggressive disease (Gleason score >7). At a mean ± SD follow-up of 3.6 ± 2.6 years, patients on metformin were less likely to experience BF at later timepoints; however, univariate analysis showed no differences at 1, 3, and 5 years. In multivariate analysis, patients on metformin were significantly less likely to experience BF at 5 years and overall in both treatment groups. In Cox regression, metformin was independently associated with a 40% relative risk reduction in BF.

CONCLUSION

In multivariate analysis, metformin use was associated with a significant risk reduction in BF overall and at 5 years following primary treatment; this trend was not witnessed in univariate analysis. This suggests the need for future investigations of metformin's role in disease-free survival in men with localized PC.