Fourteen-Year Outcome of Angle-Closure Prevention with Laser Iridotomy in the Zhongshan Angle-Closure Prevention Study: Extended Follow-up of a Randomized Controlled Trial.

PURPOSE: This study aimed to evaluate the efficacy of laser peripheral iridotomy (LPI) prophylaxis for patients with primary angle-closure suspect (PACS) after 14 years and to identify risk factors for the conversion from PACS to primary angle closure (PAC). DESIGN: Extended follow-up of the Zhongshan Angle-Closure Prevention Study. PARTICIPANTS: Eight hundred eighty-nine Chinese patients 50 to 70 years of age with bilateral PACS. METHODS: Each patient received LPI in 1 randomly selected eye, with the fellow untreated eye serving as a control. Because the risk of glaucoma was low and acute angle closure (AAC) occurred only rarely, the follow-up was extended to 14 years despite substantial benefits of LPI reported after the 6-year visit. MAIN OUTCOME MEASURES: Incidence of PAC, a composite end point including peripheral anterior synechiae, intraocular pressure (IOP) of > 24 mmHg, or AAC. RESULTS: During the 14 years, 390 LPI-treated eyes and 388 control eyes were lost to follow-up. A total of 33 LPI-treated eyes and 105 control eyes reached primary end points (P < 0.01). Within them, 1 LPI-treated eye and 5 control eyes progressed to AAC. Primary angle-closure glaucoma was found in 2 LPI-treated eyes and 4 control eyes. The hazard ratio for progression to PAC was 0.31 (95% confidence interval, 0.21-0.46) in LPI-treated eyes compared with control eyes. At the 14-year visit, LPI-treated eyes showed more severe nuclear cataract, higher IOP, and larger angle width and limbal anterior chamber depth (LACD) than control eyes. Higher IOP, shallower LACD, and greater central anterior chamber depth (CACD) were associated with an increased risk of end points developing in control eyes. In the treated group, eyes with higher IOP, shallower LACD, or less IOP elevation after the darkroom prone provocative test (DRPPT) were more likely to demonstrate PAC after LPI. CONCLUIONS: Despite a two-third decrease in PAC occurrence after LPI, the cumulative risk of progression was relatively low in the community-based PACS population over 14 years. Apart from IOP, IOP elevation after DRPPT, CACD, and LACD, more risk factors are needed to achieve precise prediction of PAC occurrence and to guide clinical practice. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Comparing survival in patients with chronic kidney disease across three countries - Results from the study of heart and renal protection-extended review.

AIM: This study examined whether survival and causes of death differed between participants enrolled from Australia (AUS), Malaysia (MYL), and New Zealand (NZ) in extended follow-up of the Study of Heart and Renal Protection (SHARP), a randomized controlled trial (RCT) of participants with moderate to severe chronic kidney disease comparing placebo to combination therapy with Simvastatin and Ezetimibe. METHODS: All participants alive at final SHARP study visit in participating centres were eligible for inclusion. Consenting participants were re-enrolled following final SHARP Study visit and followed for 5 years. Data collection included: significant medical events, hospital admissions and requirement for kidney replacement therapy. Data linkage was performed to national kidney and mortality registries. The primary outcome was all-cause mortality compared across the three countries. RESULTS: The SHARP trial randomized 2029 participants from AUS (1043/2029, 51%), MYL (701/2029, 35%), and NZ (285/2029, 14%), with 1136 participants alive and eligible for extended follow-up at the end of SHARP. In multivariable analysis, risk of death was increased for participants in MYL (HR 1.37, 95% CI 1.17-1.61, p < .001) and NZ (HR 1.28, 95% CI 1.04-1.57, p = .02) when compared to AUS participants. Adjustment for kidney transplantation as a competing risk did not explain the variation seen between countries. CONCLUSION: This study allows a better understanding of the differences in long-term mortality risk across participants from AUS, MYL, and NZ in extended follow-up of the SHARP study and demonstrates the feasibility and value of extended follow-up of participants enrolled in RCTs.

Outcome and management of newborns with congenital cytomegalovirus infection.

Congenital cytomegalovirus (CMV) infection is the most common non-genetic cause of hearing loss and neurological disorder in children. Its overall prevalence is approximately 0.5% in Europe. In France, systematic screening during pregnancy is not recommended; screening is performed only if there are maternal or fetal symptoms suggestive of this infection. Approximately 90% of infected newborns are asymptomatic at birth, and among them the risk of neurosensory sequelae is 5-15%. By contrast, the prevalence of neurosensory impairment in symptomatic newborns at birth varies from 17% to 60%. Congenital CMV infection must be confirmed at birth before the 21st day of life by polymerase chain reaction (PCR) on saliva or urine samples. A complete clinical examination, blood tests (blood count, liver function test, CMV PCR), hearing tests, brain ultrasound and eye fundus examination should be performed. Neurological and auditory follow-up must be extended well beyond the neonatal period because the occurrence of neurosensory sequelae may be delayed. Oral valganciclovir is the recommended treatment in moderate or severe congenital CMV infections for a period of 6 weeks to 6 months; such treatment requires regular monitoring because of its possible side effects.

Extended follow-up in a randomized trial of hyperbaric oxygen for persistent post-concussive symptoms.

To date, several Department of Defense (DoD) and civilian studies have evaluated hyperbaric oxygen for mild forms of traumatic brain injury. Prior to the DoD-sponsored "Brain Injury and Mechanisms of Action of Hyperbaric Oxygen for Persistent Post-Concussive Symptoms after Mild Traumatic Brain Injury (mTBI) (BIMA)" trial, none included post-intervention follow-up beyond three to six months. Post-hoc attempts at long-term follow-up were complicated by low participation and potential self-selection bias. BIMA planned for follow-up through 12 months but was amended to add post-concussive and post-traumatic stress disorder, quality of life, pain, depression, anxiety, and alcohol use assessments at 24 and 36 months. A total of 42 of 71 BIMA participants consented to extendedfollow-up, and 40 and 14 completed a 24- or 36-month visit, respectively, representing an overall response rate of 59% and 20%. Participants who completed extended follow-up were similar to the study group that did not in terms of demographics, perceived intervention allocation, and initial response to intervention. There were no significant differences at 24 or 36 months between intervention groups, and group mean scores were near pre-intervention values. This return to baseline could be due to waning treatment effect, selection bias, or participant or perception effects. Though BIMA implemented several participant retention strategies, more frequent participant contact and increased compensation might improve long-term retention in future studies. clinicaltrials.gov Identifier NCT01611194.

Long-term risk of recurrence in patients with a first unprovoked venous thromboembolism managed according to d-dimer results; A cohort study.

Essentials Long-term recurrence risk after a first unprovoked VTE with negative d-dimer levels is uncertain. Anticoagulation was stopped if d-dimer was negative, and was continued if d-dimer was positive. Five years after stopping anticoagulants, recurrent VTE was 30% in men and 17% in women. Negative d-dimers do not justify stopping anticoagulants in most men but appear to in most women. BACKGROUND: The long-term risk of recurrence in patients with a first unprovoked venous thromboembolism (VTE) who have negative d-dimer results is uncertain. OBJECTIVES: To determine this risk, including in subgroups based on sex. PATIENTS AND METHODS: ln a prospective interventional cohort study of 410 patients with a first unprovoked VTE, anticoagulants were stopped if d-dimer was negative on therapy and 1 month after stopping therapy. Other patients remained on anticoagulant therapy. We previously reported findings after a mean of 2.2 years. The current report includes 3 years of additional follow-up in 293 of these patients. RESULTS: During a median follow-up of 5.0 years, recurrent VTE after stopping therapy in response to negative d-dimer testing was 5.1% (95% confidence interval [CI], 3.6-6.5) per patient-year overall, 7.5% (95% CI, 5.5-10.0) in men, 3.8% (95% CI, 2.0-6.6) in women with VTE not associated with estrogens, and 0.4% (95% CI, 0.0-2.3) in women with VTE associated with estrogens (P < 0.001 for three-group comparison). Risk of recurrence at 5 years was 21.5% (95% CI, 16.4-26.5) overall, 29.7% (95% CI, 22.1-37.3) in men, 17.0% (95% CI, 8.1-25.9) in non-estrogen women, and 2.3% (95% CI, 0.0-6.8) in estrogen women. CONCLUSION: The long-term risk of recurrence in patients with a first unprovoked VTE who have negative d-dimer results is not low enough to justify stopping anticoagulant therapy in men, but appears to be low enough in women for many to choose stopping therapy (ClinicalTrials.gov; NCT00720915).

The use of canine mesenchymal stem cells for the autologous treatment of osteoarthritis.

Mesenchymal stem cells (MSCs) hold enormous potential for cell-based therapy in the treatment of various diseases, particularly those which currently cannot be cured and result in poor outcomes or invasive surgery. Here we present results of the application of autologous, culture-expanded, adipose tissue (AT)-derived MSCs for the osteoarthritis (OA) treatment of 10 canine patients. The stemness of isolated cells has been confirmed by their ability to differentiate into osteo- and chondrocytic lineages. The clinical effect of a single injection of ATMSCs into the symptomatic joints was evaluated by a veterinarian for five disabilities characteristic of OA at 30, 60 and 90 days after treatment, which has been designated as the initial evaluation period. Functional outcomes for all analysed characteristics improved significantly at the end of this evaluation compared with the baseline. In addition, for 5 of these 10 patients, an extended follow-up study was performed from 1 to 4 years after the initial evaluation period. We detected long-lasting positive effects on two out of five analysed characteristics. The results demonstrate that the use of autologous AT-MSCs is a successful approach to canine OA therapy.

Cardiovascular outcomes during extended follow-up of the AIM-HIGH trial cohort.

BACKGROUND: Epidemiologic studies have shown that low levels of high-density lipoprotein-cholesterol (HDL-C) and elevated triglycerides are independent predictors of cardiovascular (CV) events, though randomized trials of HDL-C-raising therapies to reduce clinical events have been largely disappointing. The Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides and Impact on Global Health Outcomes (AIM-HIGH) trial failed to show that extended release niacin (ERN) reduced CV events in patients with atherogenic dyslipidemia who were on statin-based therapy. OBJECTIVE: We sought to determine whether extended follow-up of AIM-HIGH participants changed these null results. METHODS: AIM-HIGH was a placebo-controlled trial of 3414 patients with established CV disease, low baseline HDL-C, and elevated triglycerides levels randomized to ERN 1500-2000 mg/d vs placebo. Participants also received simvastatin with or without ezetimibe to attain on-treatment low-density lipoprotein cholesterol levels of 40-80 mg/dL. The trial was halted after a mean 3-year follow-up because of futility. RESULTS: Among 3236 participants alive at the end of blinded study, 2613 (81%; ERN = 1,312, placebo = 1301) were followed a mean 1.1 additional years. Ninety-five percent of subjects remained on statin, but only 4% on ERN. At a mean total follow-up of 4.1 years, there were 343 primary CV endpoints in the ERN arm and 305 CV endpoints in placebo participants (HR 1.11, 95% CI 0.96, 1.30). Ischemic stroke was also not significantly different after extended follow-up in the two groups (2.2% vs 1.5%, P = .13). CONCLUSIONS: In patients with CV disease and atherogenic dyslipidemia on statin-based therapy, 3 years of ERN treatment did not lower CV event rates. An additional year of follow-up off assigned treatment did not alter these findings.

Low vitamin D status in relation to cardiovascular disease and mortality in Swedish women - Effect of extended follow-up.

BACKGROUND AND AIMS: The impact of vitamin D concentrations on subsequent cardiovascular disease (CVD) and overall mortality has been generally examined for periods under two decades. The magnitude of the association may depend on follow-up length. We aimed to investigate the relationship between baseline vitamin D and risk of total CVD, stroke and all-cause mortality over three decades of follow-up. Secondly, we aimed to assess how follow-up affects the associations. METHODS AND RESULTS: Concentrations of 25-hydroxyvitamin D (25D) were measured in a population-based sample of 1227 middle-aged women using serum collected at baseline and categorized into low (lowest 25D quartile) vs high 25D status (upper three 25D quartiles). Hazard ratio (HR) of the endpoints was estimated for low 25D. The impact of follow-up was examined in intermediary analyses where follow-up was interrupted up to four times, each time decreasing it by five years. There were 596 cardiovascular events and 635 participants died. During the first 17 years, the low 25D group experienced a 29% higher CVD risk and 3.3-fold higher stroke risk after accounting for confounders. Longer follow-up diminished significantly these risks and 25D status had no contribution at 32 years. For mortality, the decline over time was less dramatic, with HR = 1.96 (1.25; 3.08) at 17 years and HR = 1.42 (1.17; 1.72) at 37 years. CONCLUSION: Low 25D status increased the risk for all endpoints, but a lengthy follow-up diminished these risks towards the null. The impact of follow-up depends on the outcome. Future studies of 25D and disease should use repeated 25D assessments.

Treatment of missing data in follow-up studies of randomised controlled trials: A systematic review of the literature.

BACKGROUND/AIMS: After completion of a randomised controlled trial, an extended follow-up period may be initiated to learn about longer term impacts of the intervention. Since extended follow-up studies often involve additional eligibility restrictions and consent processes for participation, and a longer duration of follow-up entails a greater risk of participant attrition, missing data can be a considerable threat in this setting. As a potential source of bias, it is critical that missing data are appropriately handled in the statistical analysis, yet little is known about the treatment of missing data in extended follow-up studies. The aims of this review were to summarise the extent of missing data in extended follow-up studies and the use of statistical approaches to address this potentially serious problem. METHODS: We performed a systematic literature search in PubMed to identify extended follow-up studies published from January to June 2015. Studies were eligible for inclusion if the original randomised controlled trial results were also published and if the main objective of extended follow-up was to compare the original randomised groups. We recorded information on the extent of missing data and the approach used to treat missing data in the statistical analysis of the primary outcome of the extended follow-up study. RESULTS: Of the 81 studies included in the review, 36 (44%) reported additional eligibility restrictions and 24 (30%) consent processes for entry into extended follow-up. Data were collected at a median of 7 years after randomisation. Excluding 28 studies with a time to event primary outcome, 51/53 studies (96%) reported missing data on the primary outcome. The median percentage of randomised participants with complete data on the primary outcome was just 66% in these studies. The most common statistical approach to address missing data was complete case analysis (51% of studies), while likelihood-based analyses were also well represented (25%). Sensitivity analyses around the missing data mechanism were rarely performed (25% of studies), and when they were, they often involved unrealistic assumptions about the mechanism. CONCLUSION: Despite missing data being a serious problem in extended follow-up studies, statistical approaches to addressing missing data were often inadequate. We recommend researchers clearly specify all sources of missing data in follow-up studies and use statistical methods that are valid under a plausible assumption about the missing data mechanism. Sensitivity analyses should also be undertaken to assess the robustness of findings to assumptions about the missing data mechanism.

The transitioning from trials to extended follow-up studies.

BACKGROUND: Investigators may elect to extend follow-up of participants enrolled in a randomized clinical trial after the trial comes to its planned end. The additional follow-up may be initiated to learn about longer term effects of treatments, including adverse events, costs related to treatment, or for reasons unrelated to treatment such as to observe the natural course of the disease using the established cohort from the trial. PURPOSE: We examine transitioning from trials to extended follow-up studies when the goal of additional follow-up is to observe longer term treatment effects. METHODS: We conducted a literature search in selected journals from 2000 to 2012 to identify trials that extended follow-up for the purpose of studying longer term treatment effects and extracted information on the operational and logistical issues in the transition. We also draw experience from three trials coordinated by the Johns Hopkins Coordinating Centers that made transitions to extended follow-up: the Alzheimer's Disease Anti-inflammatory Prevention Trial, Multicenter Uveitis Steroid Treatment trial, and Childhood Asthma Management Program. RESULTS: Transitions are not uncommon in multicenter clinical trials, even in trials that continued to the planned end of the trial. Transitioning usually necessitates new participant consents. If study infrastructure is not maintained during the transition, participants will be lost and re-establishing the staff and facilities will be costly. Merging data from the trial and follow-up study can be complicated by changes in data collection measures and schedules. LIMITATIONS: Our discussion and recommendations are limited to issues that we have experienced in transitions from trials to follow-up studies. DISCUSSION: We discuss issues such as maintaining funding, institutional review board and consent requirements, contacting participants, and combining data from the trial and follow-up phases. We conclude with a list of recommendations to facilitate transitions from a trial to an extended follow-up study.