Strategies to Increase Cervical Cancer Screening With Mailed Human Papillomavirus Self-Sampling Kits: A Randomized Clinical Trial.

Importance: Optimal strategies for increasing cervical cancer screening may differ by patient screening history and health care setting. Mailing human papillomavirus (HPV) self-sampling kits to individuals who are overdue for screening increases adherence; however, offering self-sampling kits to screening-adherent individuals has not been evaluated in the US. Objective: To evaluate the effectiveness of direct-mail and opt-in approaches for offering HPV self-sampling kits to individuals by cervical cancer screening history (screening-adherent and currently due, overdue, or unknown). Design, Setting, and Participants: Randomized clinical trial conducted in Kaiser Permanente Washington, a US integrated health care delivery system. Individuals aged 30 to 64 years with female sex, a primary care clinician, and no hysterectomy were identified through electronic health records (EHRs) and enrolled between November 20, 2020, and January 28, 2022, with follow-up through July 29, 2022. Interventions: Individuals stratified as due (eg, at the time of randomization, these individuals have been previously screened and are due for their next screening in ≤3 months) were randomized to receive usual care (patient reminders and clinician EHR alerts [n = 3671]), education (usual care plus educational materials about screening [n = 3960]), direct mail (usual care plus educational materials and a mailed self-sampling kit [n = 1482]), or to opt in (usual care plus educational materials and the option to request a kit [n = 3956]). Individuals who were overdue for screening were randomized to receive usual care (n = 5488), education (n = 1408), or direct mail (n = 1415). Individuals with unknown history for screening were randomized to receive usual care (n = 2983), education (n = 3486), or to opt in (n = 3506). Main Outcomes and Measures: The primary outcome was screening completion within 6 months. Primary analyses compared direct-mail or opt-in participants with individuals randomized to the education group. Results: The intention-to-treat analyses included 31 355 randomized individuals (mean [SD] age, 45.9 [10.4] years). Among those who were due for screening, compared with receiving education alone (1885 [47.6%]), screening completion was 14.1% (95% CI, 11.2%-16.9%) higher in the direct-mail group (914 [61.7%]) and 3.5% (95% CI, 1.2%-5.7%) higher in the opt-in group (2020 [51.1%]). Among individuals who were overdue, screening completion was 16.9% (95% CI, 13.8%-20.0%) higher in the direct-mail group (505 [35.7%]) compared with education alone (264 [18.8%]). Among those with unknown history, screening was 2.2% (95% CI, 0.5%-3.9%) higher in the opt-in group (634 [18.1%]) compared with education alone (555 [15.9%]). Conclusions and Relevance: Within a US health care system, direct-mail self-sampling increased cervical cancer screening by more than 14% in individuals who were due or overdue for cervical cancer screening. The opt-in approach minimally increased screening. To increase screening adherence, systems implementing HPV self-sampling should prioritize direct-mail outreach for individuals who are due or overdue for screening. For individuals with unknown screening history, testing alternative outreach approaches and additional efforts to document screening history are warranted. Trial Registration: ClinicalTrials.gov Identifier: NCT04679675.

Design of a pragmatic randomized controlled trial of home-based human papillomavirus (HPV) self-sampling for increasing cervical cancer screening uptake in a U.S. healthcare system: The STEP trial.

BACKGROUND: Mailing HPV self-sampling kits to overdue individuals increases cervical cancer screening adherence; offering self-sampling to previously adherent individuals has not been evaluated in the U.S. Given heterogeneity of the U.S. health system and population, data are needed to optimize how HPV self-sampling is offered to individuals who are overdue, due after successful past screening, or have an unknown screening history. METHODS: STEP is a pragmatic randomized controlled trial set within a U.S. integrated healthcare delivery system, designed to compare different outreach approaches for offering HPV self-sampling in populations defined by prior screening behavior (previously-adherent, overdue, or unknown screening history). Over 14 months, eligible individuals were identified through electronic medical record (EMR) data and randomized to Usual Care (UC), Education (UC + educational materials about cervical cancer screening), Direct-Mail (UC + Education + a mailed self-sampling kit) or Opt-In (UC + Education + option to request a kit), depending on screening history. The primary objective is to compare screening completion by outreach approach and screening history. Secondary objectives include evaluating incremental cost-effectiveness of outreach approaches, and identifying patient preference for, and satisfaction with, HPV self-screening, and barriers to abnormal results follow-up (measured through interviews and focus groups). CONCLUSIONS: The trial was designed to generate data that U.S. health systems can use to inform primary HPV screening implementation strategies that incorporate HPV self-sampling options to improve screening access, adherence, and patient satisfaction. The objective of this report is to describe the rationale and design of this pragmatic trial.

Population Pharmacokinetics of Flucloxacillin In Bone and Soft Tissue- Standard Dosing is Not Sufficient to Achieve Therapeutic Concentrations.

PURPOSE: Flucloxacillin is a ß-lactam penicillin commonly used in the treatment of bone and soft tissue infections. In a recent porcine study, we found surprisingly low time for which the free concentration was maintained above the minimal inhibitory concentration (fT>MIC) in bone and soft tissue, following flucloxacillin oral (PO) and intravenous (IV) administration at 1g every 6h (q6h). In addition to plasma, sampling was obtained from subcutaneous tissue, knee joint, cancellous bone and cortical bone, using microdialysis. To identify flucloxacillin dosing regimens that result in theoretically therapeutic concentrations, we developed a population pharmacokinetic (PK) model for the porcine data, and combined it with a human flucloxacillin population PK model for simulations. METHODS: A four-compartment model was developed, and various dosing regimens and modes of administration were simulated. Predicted concentrations were compared to %fT>MIC (0.5 mg/L and 2 mg/L). RESULTS: Continuous infusion (CI) resulted in higher %fT>MIC compared to intermittent administration. For intermittent IV dosing (4, 8 and 12g/24h), fT>MIC (0.5 mg/L) was ≥70% in plasma, and ranged between 42-96% in the sampled tissue in a typical individual. By applying CI, 4g/day was sufficient to achieve ≥98% fT>MIC (0.5 mg/L) in all sampled tissues. For MIC 2 mg/L, ≥50% fT>MIC was only achieved in plasma at CI 8 and 12g/24h and IV 3g q6h. CONCLUSIONS: To reach efficacious flucloxacillin bone and tissue concentrations, dose increment or continuous infusion needs to be considered.

Population Pharmacokinetics of Meropenem in Plasma and Subcutis from Patients on Extracorporeal Membrane Oxygenation Treatment.

The objectives of this study were to describe meropenem pharmacokinetics (PK) in plasma and/or subcutaneous adipose tissue (SCT) in critically ill patients receiving extracorporeal membrane oxygenation (ECMO) treatment and to develop a population PK model to simulate alternative dosing regimens and modes of administration. We conducted a prospective observational study. Ten patients on ECMO treatment received meropenem (1 or 2 g) intravenously over 5 min every 8 h. Serial SCT concentrations were determined using microdialysis and compared with plasma concentrations. A population PK model of SCT and plasma data was developed using NONMEM. Time above clinical breakpoint MIC for Pseudomonas aeruginosa (8 mg/liter) was predicted for each patient. The following targets were evaluated: time for which the free (unbound) concentration is maintained above the MIC of at least 40% (40% fT>MIC), 100% fT>MIC, and 100% fT>4×MIC. For all dosing regimens simulated in both plasma and SCT, 40% fT>MIC was attained. However, prolonged meropenem infusion would be needed for 100% fT>MIC and 100% fT>4×MIC to be obtained. Meropenem plasma and SCT concentrations were associated with estimated creatinine clearance (eCLCr). Simulations showed that in patients with increased eCLCr, dose increment or continuous infusion may be needed to obtain therapeutic meropenem concentrations. In conclusion, our results show that using traditional targets of 40% fT>MIC for standard meropenem dosing of 1 g intravenously every 8 h is likely to provide sufficient meropenem concentration to treat the problematic pathogen P. aeruginosa for patients receiving ECMO treatment. However, for patients with an increased eCLCr, or if more aggressive targets, like 100% fT>MIC or 100% fT>4×MIC, are adopted, incremental dosing or continuous infusion may be needed.

Penicillin G Treatment in Infective Endocarditis Patients - Does Standard Dosing Result in Therapeutic Plasma Concentrations?

Penicillin G is frequently used to treat infective endocarditis (IE) caused by streptococci, penicillin-susceptible staphylococci and enterococci. Appropriate antibiotic exposure is essential for survival and reduces the risk of complications and drug resistance development. We determined penicillin G plasma concentration [p-penicillin] once weekly in 46 IE patients. The aim was to evaluate whether penicillin G 3 g every 6 hr (q6 h) resulted in therapeutic concentrations and to analyse potential factors that influence inter- and intra-individual variability, using linear regression and a random coefficient model. [P-penicillin] at 3 hr and at 6 hr was compared with the minimal inhibitory concentration (MIC) of the bacteria isolated from blood cultures to evaluate the following PK/PD targets: 50% fT > MIC and 100% fT > MIC. [P-penicillin] varied notably between patients and was associated with age, weight, p-creatinine and estimated creatinine clearance (eCLcr). Additionally, an increase in [p-penicillin] during the treatment period showed strong correlation with age, a low eCLcr, a low weight and a low p-albumin. Of the 46 patients, 96% had [p-penicillin] that resulted in 50% fT > MIC, while 71% had [p-penicillin] resulting in 100% fT > MIC. The majority of patients not achieving the 100% fT > MIC target were infected with enterococci. Streptococci and staphylococci isolated from blood cultures were highly susceptible to penicillin G. Our results suggest that penicillin G 3 g q6 h is suitable to treat IE caused by streptococci and penicillin-susceptible staphylococci, but caution must be taken when the infection is caused by enterococci. When treating enterococci, therapeutic drug monitoring should be applied to optimize penicillin G dosing and exposure.

Population pharmacokinetics of piperacillin in the early phase of septic shock: does standard dosing result in therapeutic plasma concentrations?

Antibiotic dosing in septic shock patients poses a challenge for clinicians due to the pharmacokinetic (PK) variability seen in this patient population. Piperacillin-tazobactam is often used for empirical treatment, and initial appropriate dosing is crucial for reducing mortality. Accordingly, we determined the pharmacokinetic profile of piperacillin (4 g) every 8 h, during the third consecutive dosing interval, in 15 patients treated empirically for septic shock. We developed a population pharmacokinetic model to assess empirical dosing and to simulate alternative dosing regimens and modes of administration. Time above the MIC (T>MIC) predicted for each patient was evaluated against clinical breakpoint MIC for Pseudomonas aeruginosa (16 mg/liter). Pharmacokinetic-pharmacodynamic (PK/PD) targets evaluated were 50% fT>4×MIC and 100% fT>MIC. A population PK model was developed using NONMEM, and data were best described by a two-compartment model. Central and intercompartmental clearances were 3.6 liters/h (relative standard error [RSE], 15.7%) and 6.58 liters/h (RSE, 16.4%), respectively, and central and peripheral volumes were 7.3 liters (RSE, 11.8%) and 3.9 liters (RSE, 9.7%), respectively. Piperacillin plasma concentrations varied considerably between patients and were associated with levels of plasma creatinine. Patients with impaired renal function were more likely to achieve predefined PK/PD targets than were patients with preserved or augmented renal function. Simulations of alternative dosing regimens showed that frequent intermittent bolus dosing as well as dosing by extended and continuous infusion increases the probability of attaining therapeutic plasma concentrations. For septic shock patients with preserved or augmented renal function, dose increment or prolonged infusion of the drug needs to be considered. (This study has been registered at ClinicalTrials.gov under registration no. NCT02306928.).

Moxifloxacin pharmacokinetic profile and efficacy evaluation in empiric treatment of community-acquired pneumonia.

When antimicrobials are used empirically, pathogen MICs equal to clinical breakpoints or epidemiological cutoff values must be considered. This is to ensure that the most resistant pathogen subpopulation is appropriately targeted to prevent emergence of resistance. Accordingly, we determined the pharmacokinetic (PK) profile of moxifloxacin at 400 mg/day in 18 patients treated empirically for community-acquired pneumonia. We developed a population pharmacokinetic model to assess the potential efficacy of moxifloxacin and to simulate the maximal MICs for which recommended pharmacokinetic-pharmacodynamic (PK-PD) estimates are obtained. Moxifloxacin plasma concentrations were determined the day after therapy initiation using ultra-high-performance liquid chromatography. Peak drug concentrations (Cmax) and area under the free drug concentration-time curve from 0 to 24 h (fAUC0-24) values predicted for each patient were evaluated against epidemiological cutoff MIC values for Streptococcus pneumoniae, Haemophilus influenzae, and Legionella pneumophila. PK-PD targets adopted were a Cmax/MIC of ≥12.2 for all pathogens, an fAUC0-24/MIC of >34 for S. pneumoniae, and an fAUC0-24/MIC of >75 for H. influenzae and L. pneumophila. Individual predicted estimates for Cmax/MIC and fAUC0-24/MIC as well as simulated maximal MICs resulting in target attainment for oral and intravenous administration of the drug were suitable for S. pneumoniae and H. influenzae but not for L. pneumophila. These results indicate that caution must be taken when moxifloxacin is used as monotherapy to treat community-acquired pneumonia caused by L. pneumophila. In conclusion, this report reveals key information relevant to the empirical treatment of community-acquired pneumonia while highlighting the robust and flexible nature of this population pharmacokinetic model to predict therapeutic success. (Clinical Trials Registration no. NCT01983839.).

Climate change effects on runoff, catchment phosphorus loading and lake ecological state, and potential adaptations.

Climate change may have profound effects on phosphorus (P) transport in streams and on lake eutrophication. Phosphorus loading from land to streams is expected to increase in northern temperate coastal regions due to higher winter rainfall and to a decline in warm temperate and arid climates. Model results suggest a 3.3 to 16.5% increase within the next 100 yr in the P loading of Danish streams depending on soil type and region. In lakes, higher eutrophication can be expected, reinforced by temperature-mediated higher P release from the sediment. Furthermore, a shift in fish community structure toward small and abundant plankti-benthivorous fish enhances predator control of zooplankton, resulting in higher phytoplankton biomass. Data from Danish lakes indicate increased chlorophyll a and phytoplankton biomass, higher dominance of dinophytes and cyanobacteria (most notably of nitrogen fixing forms), but lower abundance of diatoms and chrysophytes, reduced size of copepods and cladocerans, and a tendency to reduced zooplankton biomass and zooplankton:phytoplankton biomass ratio when lakes warm. Higher P concentrations are also seen in warm arid lakes despite reduced external loading due to increased evapotranspiration and reduced inflow. Therefore, the critical loading for good ecological state in lakes has to be lowered in a future warmer climate. This calls for adaptation measures, which in the northern temperate zone should include improved P cycling in agriculture, reduced loading from point sources, and (re)-establishment of wetlands and riparian buffer zones. In the arid Southern Europe, restrictions on human use of water are also needed, not least on irrigation.