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Open Access Publications from the University of California

Scholarly Works (15 results)

  • Article
  • Peer Reviewed
UC San Francisco Previously Published Works (2007)

Background

In 1997 the FDA approved the first double-red-blood-cell (2RBC) collection device. Soon after, travel deferral for variant Creutzfeldt-Jakob disease (vCJD) risk was adopted. To show the importance of including 2RBCs in predictive models of the blood supply, an existing whole-blood (WB) model was updated to include 2RBC collection and then run to simulate the effect of vCJD deferral on total RBC availability.

Study design and methods

The model simulates donation of allogeneic WB and 2RBCs, with donors stratified into eight age and sex groups. The model was updated with 2003 donation and economic data from 16 blood centers.

Results

The distribution of donations by demographic group differed both within and between WB and 2RBCs. Overall, 2RBC donation made up 24 percent of transfusable RBC units, at a lower per-unit acquisition cost from both the blood bank and the societal perspectives. Component fees from hospitals would alter this interpretation. The model predicts that vCJD travel deferral led to a 3.3 percent (95% confidence interval [CI], 2.3-4.1) decrease in the total number of RBC units, which was more than offset by 2RBC collection, resulting in a 10.4 percent (95% CI, 9.8%-11.1%) net increase in RBC units. Modeled 2RBC results match operational records, whereas vCJD deferral is overestimated.

Conclusion

Shifting to 2RBC collection led to a substantial gain in available RBCs: even with policies that adversely affect the quantity of RBCs in the supply, 2RBC collection results in a net gain. The economics of 2RBC collection are not as clear, however.
    • Article
    • Peer Reviewed
    UC San Francisco Previously Published Works (2011)

    Background

    Studies on colorectal cancer (CRC) screening and incidence among American Indian/Alaska Natives (AI/AN) are few.

    Aims

    Our aim was to determine CRC screening prevalence and to calculate CRC incidence among AI/AN receiving care within the Indian Health Service (IHS).

    Methods

    A retrospective cohort study of AI/AN who utilized IHS from 1996 to 2004. AI/AN who were average-risk for CRC and received primary care within IHS were identified by searching the IHS Resource Patient Management System for selected ICD-9/CPT codes (n = 142,051). CRC screening prevalence was calculated and predictors of screening were determined for this group. CRC incidence rates were ascertained for the entire AI/AN population ages 50-80 who received IHS medical care between 1996 and 2004 (n = 283,717).

    Results

    CRC screening was performed in 4.0% of average-risk AI/AN. CRC screening was more common among women than men (RR = 1.6, 95% CI 1.4-1.7) and among AI/AN living in the Alaska region compared to the Pacific Coast region (RR = 2.5, 95% CI 2.2-2.8) while patients living in the Northern Plains (RR = 0.4, 95% CI 0.3-0.4) were less likely to have been screened. CRC screening was less common among patients with a greater number of primary care visits. The age-adjusted CRC incidence among AI/AN ages 50-80 was 227 cancers per 100,000 person-years.

    Conclusions

    CRC was common among AI/AN receiving medical care within IHS. However, CRC screening prevalence was far lower than has been reported for the U.S. population.
      Cover page: Screening Prevalence and Incidence of Colorectal Cancer Among American Indian/Alaskan Natives in the Indian Health Service
      • Article
      • Peer Reviewed
      UC San Francisco Previously Published Works (2013)

      Background

      Obesity is a growing public health concern and is becoming an epidemic among veterans in the post-deployment period.

      Objective

      To explore the relationship between body mass index (BMI) and posttraumatic stress disorder (PTSD) in a large cohort of Iraq and Afghanistan veterans, and to evaluate trajectories of change in BMI over 3 years.

      Design

      Retrospective, longitudinal cohort analysis of veterans' health records

      Participants

      A total of 496,722 veterans (59,790 female and 436,932 male veterans) whose height and weight were recorded at the Department of Veterans Affairs (VA) healthcare system at least once after the end of their last deployment and whose first post-deployment outpatient encounter at the VA was at least 1 year prior to the end of the study period (December 31, 2011).

      Main measures

      BMI, mental health diagnoses.

      Key results

      Seventy-five percent of Iraq and Afghanistan veterans were either overweight or obese at baseline. Four trajectories were observed: "stable overweight" represented the largest class; followed by "stable obese;" "overweight/obese gaining;" and "obese losing." During the 3-year ascertainment period, those with PTSD and depression in particular were at the greatest risk of being either obese without weight loss or overweight or obese and continuing to gain weight. Adjustment for demographics and antipsychotic medication attenuated the relationship between BMI and certain mental health diagnoses. Although BMI trajectories were similar in men and women, some gender differences were observed. For example, the risk of being in the persistently obese class in men was highest for those with PTSD, whereas for women, the risk was highest among those with depression.

      Conclusions

      The growing number of overweight or obese returning veterans is a concerning problem for clinicians who work with these patients. Successful intervention to reduce the prevalence of obesity will require integrated efforts from primary care and mental health to treat underlying mental health causes and assist with engagement in weight loss programs.
        Cover page: The Relationship between Body Mass Index and Mental Health Among Iraq and Afghanistan Veterans
        • Article
        • Peer Reviewed
        UC San Francisco Previously Published Works (2014)

        Posttraumatic stress disorder (PTSD) is associated with a 2–4 fold increased risk of developing Type 2 diabetes mellitus. However, detailed assessments of glucose metabolism and insulin secretion in a study designed to minimize confounders are lacking. Furthermore, few studies examine potential mechanisms involved. We analyzed data from a case–control study of medically healthy, medication-free adults to determine whether individuals with PTSD had abnormal glucose or insulin response to oral glucose tolerance test (OGTT) compared to controls. Secondarily, we assessed potential mediators such as sleep, cortisol and adiponectin. Data was analyzed from 92 age and gender-matched subjects (44 PTSD, 48 controls). Chronic PTSD was diagnosed using the Structured Clinical Interview for DSM-IV and Clinician Administered PTSD Scale. Subjects underwent 75-g OGTT, actigraphy and sleep diary (to quantify sleep duration), polysomnography (to assess slow wave sleep [SWS] and delta power), and overnight blood sampling (for cortisol and adiponectin). At baseline, individuals with PTSD had mildly increased insulin levels (by 19%, compared to controls, p = 0.048) that was mediated primarily by weight. In response to OGTT, the PTSD group had higher levels of insulin at 120 min (by 44%, p = 0.03) and insulin AUC (by 43%, p = 0.015) compared to controls, after adjusting for confounders. Glucose levels were similar in the two groups. Although self-reported sleep duration, SWS, and delta power differed between PTSD subjects and controls, they did not mediate the effects of PTSD status on insulin response.

        Posttraumatic stress disorder (PTSD) is associated with a 2–4 fold increased risk of developing Type 2 diabetes mellitus. However, detailed assessments of glucose metabolism and insulin secretion in a study designed to minimize confounders are lacking. Furthermore, few studies examine potential mechanisms involved. We analyzed data from a case–control study of medically healthy, medication-free adults to determine whether individuals with PTSD had abnormal glucose or insulin response to oral glucose tolerance test (OGTT) compared to controls. Secondarily, we assessed potential mediators such as sleep, cortisol and adiponectin. Data was analyzed from 92 age and gender-matched subjects (44 PTSD, 48 controls). Chronic PTSD was diagnosed using the Structured Clinical Interview for DSM-IV and Clinician Administered PTSD Scale. Subjects underwent 75-g OGTT, actigraphy and sleep diary (to quantify sleep duration), polysomnography (to assess slow wave sleep [SWS] and delta power), and overnight blood sampling (for cortisol and adiponectin). At baseline, individuals with PTSD had mildly increased insulin levels (by 19%, compared to controls, p = 0.048) that was mediated primarily by weight. In response to OGTT, the PTSD group had higher levels of insulin at 120 min (by 44%, p = 0.03) and insulin AUC (by 43%, p = 0.015) compared to controls, after adjusting for confounders. Glucose levels were similar in the two groups. Although self-reported sleep duration, SWS, and delta power differed between PTSD subjects and controls, they did not mediate the effects of PTSD status on insulin response.

        In this case–control study, individuals with PTSD had a hyperinsulinemic response to oral glucose challenge compared to controls, suggestive of insulin resistance.

          • Article
          • Peer Reviewed
          UC San Francisco Previously Published Works (2018)

          Objectives

          To determine the relationship between manufacturer-related financial ties among investigators of published drug trials and rates of discrepant registered and published primary trial outcomes.

          Design

          Cross-sectional study.

          Setting

          Human subjects drug trials published in 'core clinical' MEDLINE journals in 2013.

          Primary and secondary outcome measures

          The primary study endpoint was the presence of a prospectively registered, clearly defined primary outcome that matched the published primary outcome for each included trial. Secondary outcomes included assessments of registration timing and quality, and the impact of outcome discrepancies between registration and publication on the statistical significance of the included trials.

          Results

          Of 192 included trials, 134 (70%) were positive and 58 (30%) were negative. Financial ties were present between first or last authors and drug manufacturers for 130 trials (68%), of which 78% were positive, versus 53% of trials with no financial ties that were positive. Clearly defined, prospectively registered outcomes that matched the published outcomes were present in just 76 of the 192 trials (40%). After adjusting for study start date and sample size, the observed relationship between investigator financial ties and the presence of a match between prospectively registered and published primary outcomes was of borderline statistical significance (OR 2.12, 95% CI 0.998 to 4.50). Studies with financial ties present were more likely than studies without ties to have been prospectively registered (78%vs48%, P<0.001) and were more likely to have prospectively registered a clearly defined primary outcome(62%vs35%, P<0.001).

          Conclusions

          Less than half of the trials in this cohort were prospectively registered with a clear primary outcome that was consistent with the primary outcome reported in the published manuscript. The presence of investigator financial ties was associated with higher quality registration practices, though this association diminished after adjusting for factors that impact registration quality.
            Cover page: Primary outcome switching among drug trials with and without principal investigator financial ties to industry: a cross-sectional study
            • Article
            • Peer Reviewed
            UC San Francisco Previously Published Works (2014)

            Rationale

            Mechanisms contributing to sex differences in the regulation of acute stress responsivity and their effect on the increased incidence of posttraumatic stress disorder (PTSD) in women are poorly understood. The reproductive hormone, progesterone, through conversion to allopregnanolone (ALLO), suppresses the hypothalamic pituitary adrenal (HPA) axis and has potent anxiolytic effects. The potential that progesterone and allopregnanolone reactivity modulate HPA axis responses and account for sex differences in PTSD has not been previously examined.

            Objective

            The present study examined the effects of sex and PTSD on adrenocorticotropic hormone (ACTH), progesterone, and allopregnanolone responses to metyrapone and whether progesterone and allopregnanolone reactivity could affect the ACTH response in PTSD.

            Methods

            Healthy medication-free male and premenopausal follicular phase female participants with chronic PTSD (n = 43; 49 % female) and controls (n = 42; 50 % female) completed an overnight metyrapone challenge and ACTH, progesterone, and allopregnanolone were obtained by repeated blood sampling.

            Results

            The increase in ACTH response to metyrapone was higher in PTSD subjects compared to controls and in women compared to men. Contrary to our initial prediction of an inverse relationship, progesterone and allopregnanolone were positively associated with ACTH. Progesterone and allopregnanolone partially mediated the relationship between PTSD and ACTH.

            Conclusions

            Our findings of increased ACTH to metyrapone in PTSD and in women may reflect heightened hypothalamic CRF hypersecretion. Progesterone and allopregnanolone partially mediated the ACTH response in PTSD. Further characterizing sex differences in these processes will advance our understanding of the pathophysiology of PTSD, and may ultimately lead to better-targeted, more effective treatment.

              • Article
              • Peer Reviewed
              UC San Francisco Previously Published Works (2023)

              Background

              While evidence-based psychotherapy (EBP) for posttraumatic stress disorder (PTSD) is a first-line treatment, its real-world effectiveness is unknown. We compared cognitive processing therapy (CPT) and prolonged exposure (PE) each to an individual psychotherapy comparator group, and CPT to PE in a large national healthcare system.

              Methods

              We utilized effectiveness and comparative effectiveness emulated trials using retrospective cohort data from electronic medical records. Participants were veterans with PTSD initiating mental healthcare (N = 265 566). The primary outcome was PTSD symptoms measured by the PTSD Checklist (PCL) at baseline and 24-week follow-up. Emulated trials were comprised of 'person-trials,' representing 112 discrete 24-week periods of care (10/07-6/17) for each patient. Treatment group comparisons were made with generalized linear models, utilizing propensity score matching and inverse probability weights to account for confounding, selection, and non-adherence bias.

              Results

              There were 636 CPT person-trials matched to 636 non-EBP person-trials. Completing ⩾8 CPT sessions was associated with a 6.4-point greater improvement on the PCL (95% CI 3.1-10.0). There were 272 PE person-trials matched to 272 non-EBP person-trials. Completing ⩾8 PE sessions was associated with a 9.7-point greater improvement on the PCL (95% CI 5.4-13.8). There were 232 PE person-trials matched to 232 CPT person-trials. Those completing ⩾8 PE sessions had slightly greater, but not statistically significant, improvement on the PCL (8.3-points; 95% CI 5.9-10.6) than those completing ⩾8 CPT sessions (7.0-points; 95% CI 5.5-8.5).

              Conclusions

              PTSD symptom improvement was similar and modest for both EBPs. Although EBPs are helpful, research to further improve PTSD care is critical.
                Cover page: Effectiveness and comparative effectiveness of evidence-based psychotherapies for posttraumatic stress disorder in clinical practice.
                • Article
                • Peer Reviewed
                UC San Francisco Previously Published Works (2019)
                BACKGROUND:Posttraumatic stress disorder (PTSD) is associated with disturbed sleep and elevated levels of pro-inflammatory cytokines, including interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Studies in animals and healthy humans have also shown that disrupted sleep elevates pro-inflammatory cytokines, including IL-6 and TNF-α. A better understanding of overnight cytokine levels and sleep might shed light on possible mechanisms for elevated inflammation in PTSD. Thus, we investigated overnight levels of IL-6 and TNF-α in individuals with and without PTSD while recording sleep polysomnography (PSG). METHOD:Serum samples were collected from otherwise healthy, medication-free participants with chronic PTSD (n = 44; 50% female; M age = 30.34 ± 8.11) and matched controls (n = 49; 53% female; M age = 30.53 ± 6.57) during laboratory PSG. Levels of IL-6 and TNF-α were measured at hours 0, 2, 4, 6, and 8 after typical sleep onset time using serial serum samples. Plasma IL-6 and TNF-α levels were quantified using enzyme-linked immunosorbent assays. RESULTS:Growth model analysis indicated a significantgroup by time interaction for IL-6 (t[247] = -2.92, p = .005) and a significant group by sex by time interaction for TNF-α (t[275] = 2.02, p = .04). PTSD positive men and women initially had higher IL-6 and TNF-α at sleep onset, but not at the end of their sleep cycle. Men with PTSD showed a peak of TNF-α at the end of the sleep cycle, whereas male control subjects demonstrated an inverted U-shaped profile. There were no significant differences in TNF-α levels overnight between women with and without PTSD. CONCLUSION:To our knowledge, this is the largest study to examine IL-6 overnight in a PTSD sample and the first study to examine overnight TNF-α in PTSD. Overnight IL-6 and TNF-α levels may be altered in individuals with PTSD compared to those without PTSD, and TNF-α trajectories also differed by sex. The current findings highlight the need to consider sex, sleep, time of day, and circadian variation when examining inflammation in PTSD. Additional research in broader study samples will be necessary to clarify associations between disrupted sleep, cytokines, and increased risk for disease in PTSD.
                  Cover page: Altered overnight levels of pro-inflammatory cytokines in men and women with posttraumatic stress disorder
                  • Article
                  • Peer Reviewed
                  UC San Francisco Previously Published Works (2019)

                  Importance

                  Randomized clinical trials have demonstrated that patients with asymptomatic carotid stenosis are eligible for carotid endarterectomy (CEA) if the 30-day surgical complication rate is less than 3% and the patient's life expectancy is at least 5 years.

                  Objective

                  To develop a risk prediction tool to improve patient selection for CEA among patients with asymptomatic carotid stenosis.

                  Design, setting, and participants

                  In this cohort study, veterans 65 years and older who received both carotid imaging and CEA in the Veterans Administration between January 1, 2005, and December 31, 2009 (n = 2325) were followed up for 5 years. Data were analyzed from January 2005 to December 2015. A risk prediction tool (the Carotid Mortality Index [CMI]) based on 23 candidate variables identified in the literature was developed using Veterans Administration and Medicare data. A simpler model based on the number of 4 key comorbidities that were prevalent and strongly associated with 5-year mortality was also developed (any cancer in the past 5 years, chronic obstructive pulmonary disease, congestive heart failure, and chronic kidney disease [the 4C model]). Model performance was assessed using measures of discrimination (eg, area under the curve [AUC]) and calibration. Internal validation was performed by correcting for optimism using 500 bootstrapped samples.

                  Main outcome and measure

                  Five-year mortality.

                  Results

                  Among 2325 veterans, the mean (SD) age was 73.74 (5.92) years. The cohort was predominantly male (98.8%) and of white race/ethnicity (94.4%). Overall, 29.5% (n = 687) of patients died within 5 years of CEA. On the basis of a backward selection algorithm, 9 patient characteristics were selected (age, chronic kidney disease, diabetes, chronic obstructive pulmonary disease, any cancer diagnosis in the past 5 years, congestive heart failure, atrial fibrillation, remote stroke or transient ischemic attack, and body mass index) for the final logistic model, which yielded an optimism-corrected AUC of 0.687 for the CMI. The 4C model had slightly worse discrimination (AUC, 0.657) compared with the CMI model; however, the calibration curve was similar to the full model in most of the range of predicted probabilities.

                  Conclusions and relevance

                  According to results of this study, use of the CMI or the simpler 4C model may improve patient selection for CEA among patients with asymptomatic carotid stenosis.
                    • Article
                    • Peer Reviewed
                    UC San Francisco Previously Published Works (2022)
                    OBJECTIVE: To assess the prevalence and correlates of prescription of sodium-glucose cotransporter 2 inhibitors (SGLT2i) and/or glucagon-like peptide 1 receptor agonists (GLP1-RA) in individuals with type 2 diabetes mellitus (T2DM) with and without chronic kidney disease (CKD). RESEARCH DESIGN AND METHODS: This was a cross-sectional analyses of SGLT2i and GLP1-RA prescriptions from 1 January 2019 to 31 December 2020 in the Veterans Health Administration System. The likelihood of prescriptions was examined by the presence or absence of CKD and by predicted risks of atherosclerotic cardiovascular disease (ASCVD) and end-stage kidney disease (ESKD). RESULTS: Of 1,197,880 adults with T2DM, SGLT2i and GLP1-RA were prescribed to 11% and 8% of patients overall, and to 12% and 10% of those with concomitant CKD, respectively. In adjusted models, patients with severe albuminuria were less likely to be prescribed SGLT2i or GLP1-RA versus nonalbuminuric patients with CKD, with odds ratios (ORs) of 0.91 (95% CI 0.89, 0.93) and 0.97 (0.94, 1.00), respectively. Patients with a 10-year ASCVD risk >20% (vs. <5%), had lower odds of SGLT2i use (OR 0.66 [0.61, 0.71]) and GLP1-RA prescription (OR 0.55 [0.52, 0.59]). A 5-year ESKD risk >5%, compared with <1%, was associated with lower likelihood of SGLT2i prescription (OR 0.63 [0.59, 0.67]) but higher likelihood of GLP1-RA prescription (OR 1.53 [1.46, 1.61]). CONCLUSIONS: Among a large cohort of patients with T2DM, prescription of SGLT2i and GLP1-RA was low in those with CKD. We observed a risk-treatment paradox, whereby patients with higher risk of adverse outcomes were less likely to receive these therapies.
                      Cover page: Prescription Patterns of Cardiovascular- and Kidney-Protective Therapies Among Patients With Type 2 Diabetes and Chronic Kidney Disease.
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