Cost-effectiveness of smoking cessation to prevent age-related macular degeneration

Smoking and treatment outcomes of neovascular age-related macular degeneration over 12 months

BACKGROUND

To assess the association of smoking with age of onset of neovascular age-related macular degeneration (nAMD), visual acuity (VA), central macular thickness (CMT) and the presence of fluid in patients with nAMD.

METHODS

547 patients with nAMD were recruited from a tertiary eye clinic during 2012-2015; of these, 490 patients were followed up 12 months later. Clinical diagnosis of nAMD was confirmed by a retinal specialist. Smoking was determined from self-reported history as never, past or current. Age of onset was defined as date of first recorded diagnosis of nAMD in either eye or date of first anti-vascular endothelial growth factor injection. CMT and presence of fluid were recorded from spectral-domain optical coherence tomography images. VA was recorded as number of letters read at 3 m.

RESULTS

After multivariable adjustment, current smokers developed nAMD at an average 5.5 years younger age than never smokers and 4.4 years younger age than past smokers (p<0.0001 and p=0.0008, respectively). At baseline, adjusted mean CMT was significantly higher in current compared with past smokers (259.2 µm vs 231.9 µm, respectively, p=0.04). Current smokers versus never smokers had greater odds of presence of subretinal fluid at 12-month follow-up: multivariable-adjusted OR 1.99 (95% CI 1.09 to 3.67). Smoking status was not significantly associated with VA over 12 months.

CONCLUSIONS

Current smoking was associated with a younger age of nAMD onset and key treatment outcomes such as higher mean CMT and greater odds of subretinal fluid presence. These findings suggest that smoking cessation may benefit patients being treated for nAMD.

The cGAS/STING pathway: a sensor of senescence-associated DNA damage and trigger of inflammation in early age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of irreversible blindness among the elderly. Considering the relatively limited effect of therapy on early AMD, it is important to focus on the pathogenesis of AMD, especially early AMD. Ageing is one of the strongest risk factors for AMD, and analysis of the impact of ageing on AMD development is valuable. Among all the ageing hallmarks, increased DNA damage accumulation is regarded as the beginning of cellular senescence and is related to abnormal expression of inflammatory cytokines, which is called the senescence-associated secretory phenotype (SASP). The exact pathway for DNA damage that triggers senescence-associated hallmarks is poorly understood. Recently, mounting evidence has shown that the cGAS/STING pathway is an important DNA sensor related to proinflammatory factor secretion and is associated with another hallmark of ageing, SASP. Thus, we hypothesized that the cGAS/STING pathway is a vital signalling pathway for early AMD development and that inhibition of STING might be a potential therapeutic strategy for AMD cases.

Health State Utility Values for Age-Related Macular Degeneration: Review and Advice

Health state utility values are a major source of uncertainty in economic evaluations of interventions for age-related macular degeneration (AMD). This review identifies and critiques published utility values and methods for eliciting de novo utility values in AMD. We describe how utility values have been used in healthcare decision making and provide guidance on the choice of utility values for future economic evaluations for AMD. Literature was searched using PubMed, and health technology assessments (HTA) were searched using HTA agency websites to identify articles reporting utility values or approaches to derive utility values in AMD and articles applying utilities for use in healthcare decision making relating to treatments for AMD. A total of 70 studies qualified for data extraction, 22 of which were classified as containing utility values and/or elicitation methods, and 48 were classified as using utility values in decision making. A large number of studies have elicited utility values for AMD, although those applied to decision making have focused on a few of these. There is an appreciation of the challenges in the measurement and valuation of health states, with recent studies addressing challenges such as the insensitivity of generic health-related quality of life (HRQoL) questionnaires and utility in the worse-seeing eye. We would encourage careful consideration when choosing utility values in decision making and an explicit critique of their applicability to the decision problem.

Mathematical Modeling in Tobacco Control Research: Initial Results From a Systematic Review

OBJECTIVES

The US Food and Drug Administration has expressed interest in using mathematical models to evaluate potential tobacco policies. The goal of this systematic review was to synthesize data from tobacco control studies that employ mathematical models.

METHODS

We searched five electronic databases on July 1, 2013 to identify published studies that used a mathematical model to project a tobacco-related outcome and developed a data extraction form based on the ISPOR-SMDM Modeling Good Research Practices. We developed an organizational framework to categorize these studies and identify models employed across multiple papers. We synthesized results qualitatively, providing a descriptive synthesis of included studies.

RESULTS

The 263 studies in this review were heterogeneous with regard to their methodologies and aims. We used the organizational framework to categorize each study according to its objective and map the objective to a model outcome. We identified two types of study objectives (trend and policy/intervention) and three types of model outcomes (change in tobacco use behavior, change in tobacco-related morbidity or mortality, and economic impact). Eighteen models were used across 118 studies.

CONCLUSIONS

This paper extends conventional systematic review methods to characterize a body of literature on mathematical modeling in tobacco control. The findings of this synthesis can inform the development of new models and the improvement of existing models, strengthening the ability of researchers to accurately project future tobacco-related trends and evaluate potential tobacco control policies and interventions. These findings can also help decision-makers to identify and become oriented with models relevant to their work.

Small effects of smoking on visual spatiotemporal processing

Nicotine is an important stimulant that is involved in modulating many neuronal processes, including those related to vision. Nicotine is also thought to play a key role in schizophrenia: A genetic variation of the cholinergic nicotine receptor gene, alpha-7 subunit (CHRNA7) has been shown to be associated with stronger backward masking deficits in schizophrenic patients. In this study, we tested visual backward masking in healthy smokers and non-smokers to further understand the effects of nicotine on spatiotemporal vision. In the first study, we tested 48 participants, a group of non-smokers (n = 12) and three groups of regular smokers that were either nicotine deprived (n = 12), non-deprived (n = 12) or deprived but were allowed to smoke a cigarette directly before the start of the experiment (n = 12). Performance was similar across groups, except for some small negative effects in nicotine-deprived participants. In the second study, we compared backward masking performance between regular smokers and non-smokers for older (n = 37, 13 smokers) and younger (n = 67, 21 smokers) adults. Older adults performed generally worse than younger adults but there were no significant differences in performance between smokers and non-smokers. Taken together, these findings indicate that nicotine has no long-term negative effects on visual spatiotemporal processing as determined by visual backward masking.

Economic evaluation of smoking-cessation therapies: a critical and systematic review of simulation models

BACKGROUND

Smoking is probably the most important among preventable health risks. Health economic evaluation of smoking-cessation interventions, applying a lifetime perspective, is made possible by available epidemiological knowledge. The well established method of performing cost-effectiveness analyses of smoking-cessation interventions involves mathematical modelling (both deterministic and stochastic) of future events important for cost effectiveness.

OBJECTIVES

This study surveys cost-effectiveness analyses of smoking cessation, with a particular focus on the mathematical modelling and simulation analyses performed.

DATA SOURCES

A systematic literature search was performed using the databases MEDLINE, Econlit and Academic Search Complete.

STUDY SELECTION

Health economic evaluations, published as full-length journal articles, were searched for.

RESULTS

423 studies were identified and 78 were finally included, of which 30 were assessed as being highly relevant, based on the application of simulation modelling.

CONCLUSIONS

In general, studies are well performed as regards modelling. Common weaknesses include reporting of modelling details; validation of used simulation models; and the handling of structural uncertainty and different types of heterogeneity.