Stephen F. Bingham

Actinic keratoses: Natural history and risk of malignant transformation in the Veterans Affairs Topical Tretinoin Chemoprevention Trial.

Actinic keratoses (AKs) are established as direct precursors of squamous cell carcinoma (SCC), but there is significant controversy regarding the rate at which AKs progress to SCC. The authors of this report studied a high‐risk population to estimate the risk of progression of AK to SCC and to basal cell carcinoma (BCC) and the risk of spontaneous regression of untreated AKs.

Association of symptomatology and cognitive deficits to functional capacity in schizophrenia

PURPOSE This study aimed to evaluate the association of positive and negative symptoms, as well as of neurocognition to functional status in patients with schizophrenia. Participants were 309 veterans with DSM-IV-diagnosed schizophrenia or schizoaffective disorder who were enrolled in a 12-month double-blind clinical trial and randomized to receive either 5 to 20 mg/d of oral olanzapine or haloperidol. Patients were assessed at study entry and at 3, 6 and 12-months on the PANSS and measures of verbal memory, verbal fluency, fine motor coordination, visual sequencing/set shifting, and conceptual reasoning. Functional status was evaluated by the Heinrichs-Carpenter Quality of Life Scale (QLS) and by days of employment in the past 30. Hierarchical regression models examined the association of functional status with symptomatology and three neurocognitive factors (motor skills, memory and card sorting), controlling for demographics and visit number. A mixed effects model was used to adjust for repeated observations from the same subjects. RESULTS The PANSS explained 16% additional variance in QLS total score after accounting for demographics and visit number (p<.001), while the neurocognitive factors explained only 4% additional variance beyond the effect of symptoms. When neurocognition was entered before symptoms, it explained an additional 8% of the variance on the QLS total score, while the PANSS explained an additional 12% over and above neurocognition. CONCLUSIONS These findings suggest that symptoms may pose an equal or greater impediment to functional capacity independent of neurocognition, at least in younger non-institutionalized people with schizophrenia.

Tretinoin and the Prevention of Keratinocyte Carcinoma (Basal and Squamous Cell Carcinoma of the Skin): A Veterans Affairs Randomized Chemoprevention Trial

Keratinocyte carcinoma (KC) is the most common cancer in the United States, with no proven means for prevention other than systemic retinoids, which have significant toxicity, and sunscreen. Topical tretinoin has been used for KC chemoprevention, although this use is unproven. Hence, we conducted the randomized Veterans Affairs Topical Tretinoin Chemoprevention Trial of high-dose topical tretinoin for KC prevention. We randomized 1,131 patients to topical 0.1% tretinoin or a matching vehicle control for 1.5-5.5 years. The primary outcomes were time to development of new basal cell carcinoma (BCC) and new invasive squamous cell carcinoma (SCC) on the face or ears. The effects were not significant (P=0.3 for BCC and P=0.4 for SCC). The proportions of the tretinoin and control groups who developed a BCC at 5 years were 53 and 54% and an invasive SCC at 5 years were 28 and 31%. These differences (95% confidence intervals) were: for BCC, 1.0% (-6.5, 8.6%); for SCC, 3.6% (-3.1, 10.3%). No differences were observed in any cancer-related end points or in actinic keratosis counts. The only quality of life difference was worse symptoms in the tretinoin group at 12 months after randomization. This trial in high-risk patients demonstrates that high-dose topical tretinoin is ineffective at reducing risk of KCs.

IMPLANTS FOR TYPE II DIABETIC PATIENTS: INTERIM REPORT

One hundred seventy-eight implants from three systems were placed in 89 type II diabetic patients at 13 Department of Veterans Affairs medical centers. Four failures (2.2 percent) were found at uncovering. The failure rate increased to 7.3 percent at the end of 1 year (nine additional failures). Study patients will be monitored for an additional 4 years. Initial results suggest that type II diabetic patients can be considered for dental implant therapy.

Topical tretinoin therapy and all-cause mortality.

OBJECTIVE To evaluate the relation of topical tretinoin, a commonly used retinoid cream, with all-cause mortality in the Veterans Affairs Topical Tretinoin Chemoprevention Trial (VATTC). The planned outcome of this trial was risk of keratinocyte carcinoma, and systemic administration of certain retinoid compounds has been shown to reduce risk of this cancer but has also been associated with increased mortality risk among smokers. DESIGN The VATTC Trial was a blinded randomized chemoprevention trial, with 2- to 6-year follow-up. Oversight was provided by multiple independent committees. SETTING US Department of Veterans Affairs medical centers. Patients A total of 1131 veterans were randomized. Their mean age was 71 years. Patients with a very high estimated short-term risk of death were excluded. Interventions Application of tretinoin, 0.1%, or vehicle control cream twice daily to the face and ears. MAIN OUTCOME MEASURES Death, which was not contemplated as an end point in the original study design. RESULTS The intervention was terminated 6 months early because of an excessive number of deaths in the tretinoin-treated group. Post hoc analysis of this difference revealed minor imbalances in age, comorbidity, and smoking status, all of which were important predictors of death. After adjusting for these imbalances, the difference in mortality between the randomized groups remained statistically significant. CONCLUSIONS We observed an association of topical tretinoin therapy with death, but we do not infer a causal association that current evidence suggests is unlikely.

Subtyping Alcoholics by Coexisting Psychiatric Syndromes: Course, Family History, Outcome

This chapter will describe two studies designed to examine the clinical validity of a relatively new method of classifying alcoholics that was derived from a descriptive, syndromatic approach to psychiatric diagnosis. The rationale for the validation studies was based upon an old model of clinical research that has been successfully used in the past to evaluate the diagnostic significance of major syndromes in both medicine and psychiatry. It is suggested that the proposed approach to subtyping alcoholics may be potentially useful to both the practitioner desirous of finding more effective methods of treatment as well as the clinical researcher interested in exploring etiological factors associated with alcoholism.

Some adaptive strategies for inadequate sample acquisition in veterans administration cooperative clinical trials.

A major concern of any clinical trial is being able to recruit sufficient patients of the proper type so that reliable answers can be obtained for the hypotheses being tested. This article considers patient recruitment in seven VA cooperative studies and the adaptive strategies used for inadequate sample acquisition. These strategies are: (1) the re-evaluation of the required sample size; (2) the addition of new hospitals; (3) the replacement of poor recruiting hospitals; (4) the extension of the patient intake period; and (5) the modification of the patient exclusion-inclusion criteria. When there is no expectation of achieving the required sample size in a reasonable time, the study is terminated. Although each of the five strategies will increase the likelihood of successfully completing a study should a recruitment problem occur, preventing these problems from occurring should be a major concern during the planning of a study.

Modest Evidence for Linkage and Possible Confirmation of Association Between NOTCH4 and Schizophrenia in a Large Veterans Affairs Cooperative Study Sample

Wei and Hemmings [2000: Nat Genet 25:376–377], using 80 British parent–offspring trios, identified a number of NOTCH4 variants and haplotypes that showed statistically significant evidence of association to schizophrenia. Specifically, the 10 repeat allele of a (CTG)n marker and the 8 repeat allele of a (TAA)n marker demonstrated excess transmission to affected individuals; SNP2 1 and haplotypes SNP2‐(CTG)n and SNP1 2 ‐SNP2‐(CTG)n also showed significant associations. In an attempt to replicate these findings, we tested for linkage and association between the same five markers used by Wei and Hemmings in 166 families collected from a multi‐center study conducted by the Department of Veterans Affairs (DVA) Cooperative Study Program (CSP). The families include 392 affected subjects (schizophrenia or schizoaffective disorder, depressed) and 216 affected sibling pairs. The families represent a mix of European Americans (n = 62, 37%), African Americans (n = 60, 36%), and racially mixed or other races (n = 44, 27%). We identified moderate evidence for linkage in the pooled race sample (LOD = 1.25) and found excess transmission of the 8 (P = 0.06) and 13 (P = 0.04) repeat alleles of the (TAA)n marker to African American schizophrenic subjects. The 8 and 13 repeat alleles were previously identified to be positively associated with schizophrenia by Wei and Hemmings [2000: Nat Genet 25:376–377] and Sklar et al. [2001: Nat Genet 28:126–128], respectively.

Predictors of basal cell carcinoma in high-risk patients in the VATTC (VA Topical Tretinoin Chemoprevention) trial

Basal cell carcinoma (BCC) is the most common cancer in the United States today, and patients who have had one are likely to have multiple carcinomas over time. Predictors of new BCCs on the face and ears among those at very high risk have not been studied in detail. We sought to do so prospectively in the context of a 6-year trial. We found that the number of BCCs in the prior 5 years was the most important predictor. Age, sun sensitivity, occupational sun exposure before the age of 30 years (but not afterward), lower educational level, history of eczema, the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, and more sunscreen use in the week, but not the 6 months, before enrollment were also independent predictors, but sunburns, baseline sun exposure, and other sun-protective measures, other skin cancers, and actinic keratoses were not. None of the eczema patients had a history of topical calcineurin use. The cumulative risk of BCC was 55% at 5 years. These findings document the key risk factors in this very high-risk population, suggesting that the history of eczema may increase the risk in those at high risk and that early sun exposure is important even in this group, and underscoring the need for chemopreventive strategies.

The “constant intake rate” assumption in interim recruitment goal methodology for multicenter clinical trials

A primary concern of any multihospital clinical trial is the recruitment of a predetermined number of patients during a prespecified interval of time. In several recent papers a Poisson based model was used to estimate the time needed to recruit a predetermined number of patients and the probabilities of recruiting specified fractions of the sample during subintervals. The Poisson model requires the assumption that patients be recruited at a constant rate over the entire length of the interval. In this paper we test the adequacy of this model and assumption using patient intake data from nine multihospital VA clinical trials and propose an alternative Bayesian model.