Improving Implementation of Lung Cancer Screening With Risk Prediction Models

Risks and Benefits of Marijuana Use: A National Survey of U.S. Adults: Annals of Internal Medicine: Vol 169, No 5

Background: Despite insufficient evidence regarding its risks and benefits, marijuana is increasingly available and is aggressively marketed to the public. Objective: To understand the public's views on the risks and benefits of marijuana use. Design: Probability-based online survey. Setting: United States, 2017. Participants: 16 280 U.S. adults. Measurements: Proportion of U.S. adults who agreed with a statement. Results: The response rate was 55.3% (n = 9003). Approximately 14.6% of U.S. adults reported using marijuana in the past year. About 81% of U.S. adults believe marijuana has at least 1 benefit, whereas 17% believe it has no benefit. The most common benefit cited was pain management (66%), followed by treatment of diseases, such as epilepsy and multiple sclerosis (48%), and relief from anxiety, stress, and depression (47%). About 91% of U.S. adults believe marijuana has at least 1 risk, whereas 9% believe it has no risks. The most common risk identified by the public was legal problems (51.8%), followed by addiction (50%) and impaired memory (42%). Among U.S. adults, 29.2% agree that smoking marijuana prevents health problems. About 18% believe exposure to secondhand marijuana smoke is somewhat or completely safe for adults, whereas 7.6% indicated that it is somewhat or completely safe for children. Of the respondents, 7.3% agree that marijuana use is somewhat or completely safe during pregnancy. About 22.4% of U.S. adults believe that marijuana is not at all addictive. Limitation: Wording of the questions may have affected interpretation. Conclusion: Americans' view of marijuana use is more favorable than existing evidence supports. Primary Funding Source: National Heart, Lung, and Blood Institute.

Mechanisms That Contribute to a Profound Reduction of the HIV-1 Reservoir After Allogeneic Stem Cell Transplant

This article has been corrected. The original version (PDF) is appended to this article as a Supplement. Background: The multifactorial mechanisms associated with radical reductions in HIV-1 reservoirs after allogeneic hematopoietic stem cell transplant (allo-HSCT), including a case of HIV cure, are not fully understood. Objective: To investigate the mechanism of HIV-1 eradication associated with allo-HSCT. Design: Nested case series within the IciStem observational cohort. Setting: Multicenter European study. Participants: 6 HIV-infected, antiretroviral-treated participants who survived more than 2 years after allo-HSCT with CCR5 wild-type donor cells. Measurements: HIV DNA analysis, HIV RNA analysis, and quantitative viral outgrowth assay were performed in blood, and HIV DNA was also measured in lymph nodes, ilea, bone marrow, and cerebrospinal fluid. A humanized mouse model was used for in vivo detection of the replication-competent blood cell reservoir. HIV-specific antibodies were measured in plasma. Results: Analysis of the viral reservoir showed that 5 of 6 participants had full donor chimera in T cells within the first year after transplant, undetectable proviral HIV DNA in blood and tissue, and undetectable replication-competent virus (<0.006 infectious unit per million cells). The only participant with detectable virus received cord blood stem cells with an antithymocyte globulin–containing conditioning regimen, did not develop graft-versus-host disease, and had delayed complete standard chimerism in T cells (18 months) with mixed ultrasensitive chimera. Adoptive transfer of peripheral CD4+ T cells to immunosuppressed mice resulted in no viral rebound. HIV antibody levels decreased over time, with 1 case of seroreversion. Limitation: Few participants. Conclusion: Allo-HSCT resulted in a profound long-term reduction in the HIV reservoir. Such factors as stem cell source, conditioning, and a possible “graft-versus-HIV-reservoir” effect may have contributed. Understanding the mechanisms involved in HIV eradication after allo-HSCT can enable design of new curative strategies. Primary Funding Source: The Foundation for AIDS Research (amfAR).

Defining, Estimating, and Communicating Overdiagnosis in Cancer Screening

The toll of inadequate health care is well-substantiated, but recognition is mounting that “too much” is also possible. Overdiagnosis represents one harm of too much medicine, but the concept can be confusing: It is often conflated with related harms (such as overtreatment, misclassification, false-positive results, and overdetection) and is difficult to measure because it cannot be directly observed. Because the U.S. Preventive Services Task Force (USPSTF) issues screening recommendations aimed largely at healthy persons, it has a particular interest in understanding harms related to screening, especially but not limited to overdiagnosis. In support of the USPSTF, the authors summarize the knowledge and provide guidance on defining, estimating, and communicating overdiagnosis in cancer screening. To improve consistency, thinking, and reporting about overdiagnosis, they suggest a specific definition. The authors articulate how variation in estimates of overdiagnosis can arise, identify approaches to estimating overdiagnosis, and describe best practices for communicating the potential for harm due to overdiagnosis.

Treatments of Primary Basal Cell Carcinoma of the Skin: A Systematic Review and Network Meta-analysis: Annals of Internal Medicine: Vol 169, No 7

Background: Most interventions for basal cell carcinoma (BCC) have not been compared in head-to-head randomized trials. Purpose: To evaluate the comparative effectiveness and safety of treatments of primary BCC in adults. Data Sources: English-language searches of MEDLINE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Embase from inception to May 2018; reference lists of guidelines and systematic reviews; and a search of ClinicalTrials.gov in August 2016. Study Selection: Comparative studies of treatments currently used in adults with primary BCC. Data Extraction: One investigator extracted data on recurrence, histologic clearance, clinical clearance, cosmetic outcomes, quality of life, and mortality, and a second reviewer verified extractions. Several investigators evaluated risk of bias for each study. Data Synthesis: Forty randomized trials and 5 nonrandomized studies compared 18 interventions in 9 categories. Relative intervention effects and mean outcome frequencies were estimated using frequentist network meta-analyses. Estimated recurrence rates were similar for excision (3.8% [95% CI, 1.5% to 9.5%]), Mohs surgery (3.8% [CI, 0.7% to 18.2%]), curettage and diathermy (6.9% [CI, 0.9% to 36.6%]), and external-beam radiation (3.5% [CI, 0.7% to 16.8%]). Recurrence rates were higher for cryotherapy (22.3% [CI, 10.2% to 42.0%]), curettage and cryotherapy (19.9% [CI, 4.6% to 56.1%]), 5-fluorouracil (18.8% [CI, 10.1% to 32.5%]), imiquimod (14.1% [CI, 5.4% to 32.4%]), and photodynamic therapy using methyl-aminolevulinic acid (18.8% [CI, 10.1% to 32.5%]) or aminolevulinic acid (16.6% [CI, 7.5% to 32.8%]). The proportion of patients reporting good or better cosmetic outcomes was better for photodynamic therapy using methyl-aminolevulinic acid (93.8% [CI, 79.2% to 98.3%]) or aminolevulinic acid (95.8% [CI, 84.2% to 99.0%]) than for excision (77.8% [CI, 44.8% to 93.8%]) or cryotherapy (51.1% [CI, 15.8% to 85.4%]). Data on quality of life and mortality were too sparse for quantitative synthesis. Limitation: Data are sparse, and effect estimates are imprecise and informed by indirect comparisons. Conclusion: Surgical treatments and external-beam radiation have low recurrence rates for the treatment of low-risk BCC, but substantial uncertainty exists about their comparative effectiveness versus other treatments. Gaps remain regarding high-risk BCC subtypes and important outcomes, including costs. Primary Funding Source: Agency for Healthcare Research and Quality. (PROSPERO: CRD42016043353).

Use of High-Sensitivity Cardiac Troponin for the Exclusion of Inducible Myocardial Ischemia: A Cohort Study: Annals of Internal Medicine: Vol 169, No 11

Background: Many patients with coronary artery disease (CAD) are routinely referred for surveillance stress testing despite recommendations against it. Objective: To determine whether low levels of resting high-sensitivity cardiac troponin I (hs-cTnI) can identify persons without inducible myocardial ischemia. Design: Observational study. Setting: A university-affiliated hospital network. Patients: Persons with stable CAD: 589 in the derivation group and 118 in the validation cohort. Measurements: Presence of inducible myocardial ischemia was determined by myocardial perfusion imaging with technetium-99m single-photon emission computed tomography during either treadmill or pharmacologic stress testing. Resting plasma hs-cTnI was measured within 1 week of the stress test, and the negative predictive value (NPV) for inducible ischemia was calculated. The derivation cohort was followed for 3 years for incident cardiovascular death and myocardial infarction. Results: In the derivation cohort, 10 of 101 patients with an hs-cTnI level below 2.5 pg/mL had inducible myocardial ischemia (NPV, 90% [95% CI, 83% to 95%]) and 3 of 101 had inducible ischemia involving at least 10% of the myocardium (NPV, 97% [CI, 92% to 99%]). In the validation cohort, 4 of 32 patients with an hs-cTnI level below 2.5 pg/mL had inducible ischemia (NPV, 88% [CI, 71% to 96%]) and 2 of 32 had ischemia of 10% or greater (NPV, 94% [CI, 79% to 99%]). After a median follow-up of 3 years in the derivation cohort, no adverse events occurred in patients with an hs-cTnI level below 2.5 pg/mL, compared with 33 (7%) cardiovascular deaths or incident myocardial infarctions among those with an hs-cTnI level of 2.5 pg/mL or greater. Limitation: The data may not be applicable to a population without known CAD or to persons with unstable angina, and the modest sample sizes warrant further validation in a larger cohort. Conclusion: Very low hs-cTnI levels may be useful in excluding inducible myocardial ischemia in patients with stable CAD. Primary Funding Source: National Institutes of Health.

The Letter

Screening for Urinary Incontinence in Women: A Recommendation From the Women's Preventive Services Initiative

This article has been corrected. The original version (PDF) is appended to this article as a Supplement. Description: Recommendation on screening for urinary incontinence in women by the Women's Preventive Services Initiative (WPSI), a national coalition of women's health professional organizations and patient representatives. The WPSI's recommendations are intended to guide clinical practice and coverage of services for the Health Resources and Services Administration and other stakeholders. The target audience for this recommendation includes all clinicians providing preventive health care for women, particularly in primary care settings. This recommendation applies to women of all ages, as well as adolescents. Methods: The WPSI developed this recommendation after evaluating evidence regarding the benefits and harms of screening for urinary incontinence in women. The evaluation included a systematic review of the accuracy of screening instruments and the benefits and harms of treatments. Indirect evidence was used to link screening and health outcomes in the chain of evidence that might support screening in the absence of direct evidence. The WPSI also considered the effect of screening on symptom progression and avoidance of costly and complex treatments, as well as implementation factors. Recommendation: The WPSI recommends screening women for urinary incontinence annually. Screening ideally should assess whether women experience urinary incontinence and whether it affects their activities and quality of life. The WPSI recommends referring women for further evaluation and treatment if indicated.

Marijuana Use, Respiratory Symptoms, and Pulmonary Function: A Systematic Review and Meta-analysis: Annals of Internal Medicine: Vol 169, No 2

Background: The health effects of smoking marijuana are not well-understood. Purpose: To examine the association between marijuana use and respiratory symptoms, pulmonary function, and obstructive lung disease among adolescents and adults. Data Sources: PubMed, Embase, PsycINFO, MEDLINE, and the Cochrane Library from 1 January 1973 to 30 April 2018. Study Selection: Observational and interventional studies published in English that reported pulmonary outcomes of adolescents and adults who used marijuana. Data Extraction: Four reviewers independently extracted study characteristics and assessed risk of bias. Three reviewers assessed strength of evidence. Studies of similar design with low or moderate risk of bias and sufficient data were pooled. Data Synthesis: Twenty-two studies were included. A pooled analysis of 2 prospective studies showed that marijuana use was associated with an increased risk for cough (risk ratio [RR], 2.04 [95% CI, 1.02 to 4.06]) and sputum production (RR, 3.84 [CI, 1.62 to 9.07]). Pooled analysis of cross-sectional studies (1 low and 3 moderate risk of bias) showed that marijuana use was associated with cough (RR, 4.37 [CI, 1.71 to 11.19]), sputum production (RR, 3.40 [CI, 1.99 to 5.79]), wheezing (RR, 2.83 [CI, 1.89 to 4.23]), and dyspnea (RR, 1.56 [CI, 1.33 to 1.83]). Data on pulmonary function and obstructive lung disease were insufficient. Limitation: Few studies were at low risk of bias, marijuana exposure was limited in the population studied, cohorts were young overall, assessment of marijuana exposure was not uniform, and study designs varied. Conclusion: Low-strength evidence suggests that smoking marijuana is associated with cough, sputum production, and wheezing. Evidence on the association between marijuana use and obstructive lung disease and pulmonary function is insufficient. Primary Funding Source: None. (PROSPERO: CRD42017059224)

On-Demand Sildenafil as a Treatment for Raynaud Phenomenon: A Series of n-of-1 Trials: Annals of Internal Medicine: Vol 169, No 10

Background: Treatment of Raynaud phenomenon (RP) with phosphodiesterase-5 inhibitors has shown moderate efficacy. Adverse effects decrease the risk–benefit profile of these drugs, and patients may not be willing to receive long-term treatment. On-demand single doses before or during exposure to cold may be a good alternative. Objective: To assess the efficacy and safety of on-demand sildenafil in RP. Design: Series of randomized, double-blind, n-of-1 trials. (ClinicalTrials.gov: NCT02050360) Setting: Outpatients at a French university hospital. Participants: Patients with primary or secondary RP. Intervention: Each trial consisted of a multiple crossover study in a single patient. Repeated blocks of 3 periods of on-demand treatment were evaluated: 1 week of placebo, 1 week of sildenafil at 40 mg per dose, and 1 week of sildenafil at 80 mg per dose, with a maximum of 2 doses daily. Measurements: Raynaud Condition Score (RCS) and frequency and daily duration of attacks. Skin blood flow in response to cooling also was assessed with laser speckle contrast imaging. Mixed-effects models were used and parameters were estimated in a Bayesian framework to determine individual and aggregated efficacy. Results: 38 patients completed 2 to 5 treatment blocks. On the basis of aggregated data, the probability that sildenafil at 40 mg or 80 mg was more effective than placebo was greater than 90% for all outcomes (except for RCS with sildenafil, 80 mg). However, the aggregated effect size was not clinically relevant. Yet, substantial heterogeneity in sildenafil's efficacy was observed among participants, with clinically relevant efficacy in some patients. Limitation: The response to sildenafil was substantially heterogeneous among patients. Conclusion: Despite a high probability that sildenafil is superior to placebo, substantial heterogeneity was observed in patient response and aggregated results did not show that on-demand sildenafil has clinically relevant efficacy. In this context, the use of n-of-1 trials may be an original and relevant approach in RP. Primary Funding Source: GIRCI (Groupement Interrégional de Recherche Clinique et d'Innovation) Auvergne Rhône-Alpes (academic funding) and Pfizer.