Stanford Health Policy is a joint effort of the Freeman Spogli Institute for International Studies and the Stanford School of Medicine
Background: Effective strategies for managing patients with solitary pulmonary nodules (SPN) depend critically on the pre-test probability of malignancy.
Objective: To validate two previously developed models that estimate the probability that an indeterminate solitary pulmonary nodule (SPN) is malignant, based on clinical characteristics and radiographic findings.
Methods: We retrospectively collected data on age, smoking and cancer history, nodule size, location, and spiculation from the medical records of 151 veterans (145 men, 6 women; range 39 to 87 years) with an SPN measuring 7 to 30 mm (inclusive) and a final diagnosis established by histopathology or 2-year follow-up. We compared each patient's final diagnosis to the probability of malignancy predicted by two models: one developed by investigators at the Mayo Clinic and another that we developed from patients enrolled in a VA Cooperative Study. We assessed model accuracy by calculating areas under the receiver operating characteristic (ROC) curve and model calibration by comparing predicted and observed rates of malignancy.
Results: The area under the ROC curve for the Mayo Clinic model (0.80; 95% CI 0.72-0.88) was higher than that of the VA model (0.73; 95% CI 0.64-0.82), but this difference was not statistically significant (Delta=0.07; 95% CI -0.03 to 0.16). Calibration curves showed that the probability of malignancy was underestimated by the Mayo Clinic model and overestimated by the VA model.
Conclusions: Two existing prediction models are sufficiently accurate to guide decisions about the selection and interpretation of subsequent diagnostic tests in patients with SPNs, although clinicians should also consider the prevalence of malignancy in their practice setting when choosing a model.
This issue of CHP/PCOR's Quarterly Update covers news from the Spring 2007 quarter and includes articles about:
The primary study objective is to conduct a prospective, randomized controlled clinical trial that compares the effectiveness of two approaches for delivering smoking cessation treatment for veterans with posttraumatic stress disorder (PTSD). An approach where smoking cessation treatment is integrated into mental health care for PTSD and delivered by mental health providers (experimental condition) will be compared to specialized smoking cessation clinic referral (VA's usual standard of care).
Secondary study objectives are to (a) compare the cost outcomes and cost-effectiveness of IC versus USC, (b) identify treatment process variables that explain (mediate) observed differences in smoking abstinence rates for the two study conditions, and (c) determine whether cessation from smoking is associated with worsening of symptoms of PTSD and/or depression.
Purpose: Lung cancer is a leading cause of cancer death worldwide. Although smoking remains the predominant cause of lung cancer, lung cancer in never smokers is an increasingly prominent public health issue. However, data on this topic, particularly lung cancer incidence rates in never smokers, are limited.
Methods: We reviewed the existing literature on lung cancer incidence and mortality rates among never smokers and present new data regarding rates in never smokers from the following large, prospective cohorts: Nurses' Health Study; Health Professionals Follow-Up Study; California Teachers Study; Multiethnic Cohort Study; Swedish Lung Cancer Register in the Uppsala/Orebro region; and First National Health and Nutrition Examination Survey Epidemiologic Follow-Up Study.
Results: Truncated age-adjusted incidence rates of lung cancer among never smokers age 40 to 79 years in these six cohorts ranged from 14.4 to 20.8 per 100,000 person-years in women and 4.8 to 13.7 per 100,000 person-years in men, supporting earlier observations that women are more likely than men to have non-smoking-associated lung cancer. The distinct biology of lung cancer in never smokers is apparent in differential responses to epidermal growth factor receptor inhibitors and an increased prevalence of adenocarcinoma histology in never smokers.
Conclusion: Lung cancer in never smokers is an important public health issue, and further exploration of its incidence patterns, etiology, and biology is needed.
Objective: Relatively little is known about the intergenerational mechanisms that lead to social disparities in child health. We examined whether the association between low socioeconomic status (SES) and child behavior problems is mediated by maternal health conditions and behavior.
Methods: Prospective cohort data (1979-1998) on 2,677 children and their mothers were obtained from the National Longitudinal Survey of Youth. SES, the Child Behavior Problems Index (BPI), and maternal smoking, depressive symptoms, and alcohol use before, during, and after pregnancy were examined.
Results: Lower income and lower maternal education were associated with increased child BPI scores. Adjustment for maternal smoking, depressive symptoms, and alcohol use attenuated the associations between SES and child BPI by 26% to 49%. These maternal health conditions often occurred together, persisted over time, and were associated with the mother's own childhood SES and pre-pregnancy health.
Conclusions: Social disparities in women's health conditions may help shape the
likelihood of behavior problems in the subsequent generation. Improved public
health programs and services for disadvantaged women across the lifecourse may
not only address their own urgent health needs, but reduce social disparities in the health and well-being of their children.
We compared the cost-effectiveness of a free nicotine replacement therapy (NRT) program with a statewide smoke-free workplace policy in Minnesota. We conducted 1-year simulations of costs and benefits. The number of individuals who quit smoking and the quality-adjusted life years (QALYs) were the measures of benefits. After 1 year, a NRT program generated 18,500 quitters at a cost of 7020 dollars per quitter (4440 dollars per QALY), and a smoke-free workplace policy generated 10,400 quitters at a cost of 799 dollars per quitter (506 dollars per QALY). Smoke-free work-place policies are about 9 times more cost-effective per new nonsmoker than free NRT programs are. Smoke-free workplace policies should be a public health funding priority, even when the primary goal is to promote individual smoking cessation.
Background: An increase in the incidence of esophageal adenocarcinoma has coincided with a decrease in the prevalence of Helicobacter pylori infection. Whether these 2 phenomena are associated is unknown.
Methods: We conducted a nested case-control study of 128,992 members of an integrated health care system who had participated in a multiphasic health checkup (MHC) during 1964-1969. During follow-up, 52 patients developed esophageal adenocarcinoma. Three randomly chosen control subjects from the MHC cohort were matched to each case subject, on the basis of age at the MHC, sex, race, and the date and site of the MHC. Data on cigarette smoking, alcohol consumption, body mass index (BMI), and education level were obtained at the MHC. Serum samples collected at the MHC were tested for IgG antibodies to H. pylori and to the H. pylori CagA protein.
Results: Subjects with H. pylori infections were less likely than uninfected subjects to develop esophageal adenocarcinoma (odds ratio [OR], 0.37 [95% confidence interval (CI), 0.16-0.88]). This significant association was restricted to case subjects and control subjects 50 years old at the MHC (OR, 0.20 [95% CI, 0.06-0.68]). In patients with H. pylori infections, the OR for those who tested positive for IgG antibodies to the CagA protein was similar to that for those who tested negative for it. BMI >/=25 and cigarette smoking were strong independent risk factors for development of esophageal adenocarcinoma.
Conclusion: The absence of H. pylori infection, independent of cigarette smoking and BMI, is associated with a markedly increased risk of development of esophageal adenocarcinoma.
Adolescent smokers (N = 211) were randomized to 1 of 2 groups: (a) nicotine patch plus bupropion SR (sustained release; 150 mg per day) or (b) nicotine patch plus placebo. Group skills training sessions were conducted each week by research staff. Abstinence rates at Weeks 10 and 26 were as follows: (a) patch plus bupropion, 23% and 8%, (b) patch plus placebo, 28% and 7%. Despite the lack of a treatment effect, a large majority of adolescents in both treatment groups reduced their consumption to a few cigarettes per day or less and maintained this reduction over time. Similarly, an examination of survival curves revealed that by the end of treatment many had managed to avoid a return to daily smoking. These findings are encouraging and suggest new avenues for research. For example, treatments of the kind examined in this report, augmented by extended maintenance therapies, may yield higher long-term success rates.