The impact of loss to follow-up in the Dutch organised HPV-based cervical cancer screening programme

Loss to follow-up (LTFU) within cervical screening programmes can result in missed clinically relevant lesions, potentially reducing programme effectiveness. To examine the health impact of losing women during the screening process, we determined the proportion of women LTFU per step of the Dutch hrHPV-based screening programme. We then determined the probability of being LTFU by age, screening history and sampling method (self- or clinician-sampled) using logistic regression analysis. Finally, we estimated the number of missed CIN2+/3+ lesions per LTFU moment by using the CIN-risk in women compliant with follow-up. Data from the Dutch nationwide pathology databank (Palga) was used. Women eligible for screening in 2017 and 2018 were included (N = 840,428). For clinician collected (CC) samples, the highest proportion LTFU was found following 'referral advice for colposcopy' (5.5% after indirect referral; 3.8% after direct referral). For self-sampling, the highest proportions LTFU were found following the advice for repeat cytology (13.6%) and after referral advice for colposcopy (8.2% after indirect referral; 4.3% after direct referral). Self-sampling users and women with no screening history had a higher LTFU-risk (OR: 3.87, CI: 3.55-4.23; OR: 1.39, CI: 1.20-1.61) compared to women that used CC sampling and women that have been screened before, respectively. Of all women LTFU in 2017/18, the total number of potentially missed CIN2+ was 844 (21% of women LTFU). Most lesions were missed after 'direct referral for colposcopy' (N = 462, 11.5% of women LTFU). So, this indicates a gap between the screening programme and clinical care which requires further attention, by improving monitoring of patients after referral.

Risk factors for loss to follow-up after the start of direct-acting antiviral treatment for hepatitis C virus infection

Background and Aim

Direct-acting antivirals (DAAs) have recently been developed to treat hepatitis C virus (HCV) infection. Additionally, interferon-free DAA treatment has improved liver function and reduced the risk of hepatocellular carcinoma (HCC) following HCV eradication. Previous studies on HCV have focused mainly on the treatment rate and the risk of developing HCC, and less attention has been given to loss to follow-up (LTFU) after DAA treatment. Therefore, the present study aimed to identify the definitive risk factors for LTFU after the start of DAA treatment.

Methods

Between September 2017 and March 2022, 296 patients receiving glecaprevir and pibrentasvir for HCV infection were enrolled in this study. The incidence of LTFU following DAA treatment and the risk factors contributing to LTFU were identified using the patients' clinical characteristics.

Results

In the present study, 75 patients (25.3%) interrupted their follow-up visits. Multivariate logistic analysis revealed a history of injection drug use (hazard ratio [HR], 1.81; P = 0.017), treatment duration (8 weeks) (HR, 3.51; P = 0.0033), and age <70 years (HR, 1.9; P = 0.0422) as independent factors associated with LTFU after the start of DAA treatment.

Conclusion

Young patients and those with injection drug use are likely to discontinue their follow-up visits after the start of DAA treatment for HCV infection. Therefore, these patients require strict supervision.

Bias and Loss to Follow-Up in Cardiovascular Randomized Trials: A Systematic Review

Background Loss to follow-up (LTFU) is common in randomized controlled trials. However, its potential impact on primary outcomes from cardiovascular randomized controlled trials is not known. Methods and Results We conducted a prospective systematic review (PROSPERO: CRD42019121959) for randomized controlled trials published in 8 leading journals over 5 years from January 2014 to December 2018. Extent, reporting, and handling of LTFU data were recorded, and the proportion of a trial's primary outcome results that lose statistical significance was calculated after making plausible assumptions for the intervention and control arms. These assumptions could drive differential treatment effects between the groups considering relative event incidence between LTFU participants and those included in the primary outcome. We identified 117 randomized controlled trials of which 91 (78%) trials reported LTFU, 23 (20%) reported no LTFU, and 3 (3%) trials did not report on whether LTFU occurred. The median percentage of study participants lost to follow-up was 2% (interquartile range, 0.33%-5.3%). Only 10 trials (9%) had a low cluster of risk factors for impairment in trial quality. The percentage of trials losing statistical significance varied from 2% when the relative event incidence for LTFU between the randomized groups was 1 for the intervention arm and 1.5 for the control arm to 16% when the relative event incidence was 3 for the intervention arm and 1 for the control arm. Conclusions Almost 1 in 6 (16%) cardiovascular randomized trials published in leading journals may have a change in the primary outcome if plausible assumptions are made about differential event rates of participants lost to follow up. There is scope for improvement arising from LTFU in randomized trials in cardiovascular medicine. Registration URL: https://www.crd.york.ac.uk/prospero; Unique identifier: CRD42019121959.

Loss to programme between HIV diagnosis and initiation of antiretroviral therapy in sub-Saharan Africa: systematic review and meta-analysis

OBJECTIVES

To assess the proportion of patients lost to programme (died, lost to follow-up, transferred out) between HIV diagnosis and start of antiretroviral therapy (ART) in sub-Saharan Africa, and determine factors associated with loss to programme.

METHODS

Systematic review and meta-analysis. We searched PubMed and EMBASE databases for studies in adults. Outcomes were the percentage of patients dying before starting ART, the percentage lost to follow-up, the percentage with a CD4 cell count, the distribution of first CD4 counts and the percentage of eligible patients starting ART. Data were combined using random-effects meta-analysis.

RESULTS

Twenty-nine studies from sub-Saharan Africa including 148,912 patients were analysed. Six studies covered the whole period from HIV diagnosis to ART start. Meta-analysis of these studies showed that of the 100 patients with a positive HIV test, 72 (95% CI 60-84) had a CD4 cell count measured, 40 (95% CI 26-55) were eligible for ART and 25 (95% CI 13-37) started ART. There was substantial heterogeneity between studies (P < 0.0001). Median CD4 cell count at presentation ranged from 154 to 274 cells/μl. Patients eligible for ART were less likely to become lost to programme (25%vs. 54%, P < 0.0001), but eligible patients were more likely to die (11%vs. 5%, P < 0.0001) than ineligible patients. Loss to programme was higher in men, in patients with low CD4 cell counts and low socio-economic status and in recent time periods.

CONCLUSIONS

Monitoring and care in the pre-ART time period need improvement, with greater emphasis on patients not yet eligible for ART.