Investigating the accuracy of blood oxygen saturation measurements in common consumer smartwatches

Blood oxygen saturation (SpO2) is an important measurement for monitoring patients with acute and chronic conditions that are associated with low blood oxygen levels. While smartwatches may provide a new method for continuous and unobtrusive SpO2 monitoring, it is necessary to understand their accuracy and limitations to ensure that they are used in a fit-for-purpose manner. To determine whether the accuracy of and ability to take SpO2 measurements from consumer smartwatches is different by device type and/or by skin tone, our study recruited patients aged 18-85 years old, with and without chronic pulmonary disease, who were able to provide informed consent. The mean absolute error (MAE), mean directional error (MDE) and root mean squared error (RMSE) were used to evaluate the accuracy of the smartwatches as compared to a clinical grade pulse oximeter. The percent of data unobtainable due to inability of the smartwatch to record SpO2 (missingness) was used to evaluate the measurability of SpO2 from the smartwatches. Skin tones were quantified based on the Fitzpatrick (FP) scale and Individual Typology Angle (ITA), a continuous measure of skin tone. A total of 49 individuals (18 female) were enrolled and completed the study. Using a clinical-grade pulse oximeter as the reference standard, there were statistically significant differences in accuracy between devices, with Apple Watch Series 7 having measurements closest to the reference standard (MAE = 2.2%, MDE = -0.4%, RMSE = 2.9%) and the Garmin Venu 2s having measurements farthest from the reference standard (MAE = 5.8%, MDE = 5.5%, RMSE = 6.7%). There were also significant differences in measurability across devices, with the highest data presence from the Apple Watch Series 7 (88.9% of attempted measurements were successful) and the highest data missingness from the Withings ScanWatch (only 69.5% of attempted measurements were successful). The MAE, RMSE and missingness did not vary significantly across FP skin tone groups, however, there may be a relationship between FP skin tone and MDE (intercept = 0.04, beta coefficient = 0.47, p = 0.04). No statistically significant difference was found between skin tone as measured by ITA and MAE, MDE, RMSE or missingness.

Contemporary trends in PGD incidence, outcomes, and therapies

BACKGROUND

We sought to describe trends in extracorporeal membrane oxygenation (ECMO) use, and define the impact on PGD incidence and early mortality in lung transplantation.

METHODS

Patients were enrolled from August 2011 to June 2018 at 10 transplant centers in the multi-center Lung Transplant Outcomes Group prospective cohort study. PGD was defined as Grade 3 at 48 or 72 hours, based on the 2016 PGD ISHLT guidelines. Logistic regression and survival models were used to contrast between group effects for event (i.e., PGD and Death) and time-to-event (i.e., death, extubation, discharge) outcomes respectively. Both modeling frameworks accommodate the inclusion of potential confounders.

RESULTS

A total of 1,528 subjects were enrolled with a 25.7% incidence of PGD. Annual PGD incidence (14.3%-38.2%, p = .0002), median LAS (38.0-47.7 p = .009) and the use of ECMO salvage for PGD (5.7%-20.9%, p = .007) increased over the course of the study. PGD was associated with increased 1 year mortality (OR 1.7 [95% C.I. 1.2, 2.3], p = .0001). Bridging strategies were not associated with increased mortality compared to non-bridged patients (p = .66); however, salvage ECMO for PGD was significantly associated with increased mortality (OR 1.9 [1.3, 2.7], p = .0007). Restricted mean survival time comparison at 1-year demonstrated 84.1 days lost in venoarterial salvaged recipients with PGD when compared to those without PGD (ratio 1.3 [1.1, 1.5]) and 27.2 days for venovenous with PGD (ratio 1.1 [1.0, 1.4]).

CONCLUSIONS

PGD incidence continues to rise in modern transplant practice paralleled by significant increases in recipient severity of illness. Bridging strategies have increased but did not affect PGD incidence or mortality. PGD remains highly associated with mortality and is increasingly treated with salvage ECMO.

Remote Therapy to Improve Outcomes in Lung Transplant Recipients: Design of the INSPIRE-III Randomized Clinical Trial

BACKGROUND

Impaired functional capacity and emotional distress are associated with lower quality of life (QoL) and worse clinical outcomes in post lung transplant patients. Strategies to increase physical activity and reduce distress are needed.

METHODS

The Investigational Study of Psychological Interventions in Recipients of Lung Transplant-III study is a single site, parallel group randomized clinical trial in which 150 lung transplant recipients will be randomly assigned to 3 months of telephone-delivered coping skills training combined with aerobic exercise (CSTEX) or to a Standard of Care plus Education control group. The primary endpoints are a global measure of distress and distance walked on the 6-Minute Walk Test. Secondary outcomes include measures of transplant-specific QoL, frailty, health behaviors, and chronic lung allograft dysfunction-free survival.

RESULTS

Participants will be evaluated at baseline, at the conclusion of 3 months of weekly treatment, at 1-year follow-up, and followed annually thereafter for clinical events for up to 4 years (median = 2 y). We also will determine whether functional capacity, distress, and health behaviors (eg, physical activity, medication adherence, and volume of air forcefully exhaled in 1 second (FEV1), mediate the effects of the CSTEX intervention on clinical outcomes.

CONCLUSIONS

Should the CSTEX intervention result in better outcomes compared with the standard of care plus post-transplant education, the remotely delivered CSTEX intervention can be made available to all lung transplant recipients as a way of enhancing their QoL and improving clinical outcomes.

Predictors of death or lung transplant after a diagnosis of idiopathic pulmonary fibrosis: insights from the IPF-PRO Registry

Background

Idiopathic pulmonary fibrosis (IPF) is a progressive disease with a variable clinical course and high mortality. We used data from a large national US registry of patients with IPF to investigate relationships between patient characteristics, including markers of disease severity, and mortality.

Methods

The analysis cohort comprised patients enrolled in the IPF-PRO Registry from its inception on 5 June 2014 to 26 October 2017. The primary criterion for inclusion in this registry is that patients must be diagnosed or confirmed with IPF at the enrolling centre within 6 months. Associations between patient characteristics and markers of disease severity at enrolment and mortality outcomes were investigated using univariable, multivariable and adjustment models.

Results

Among 662 patients enrolled, 111 patients died or had a lung transplant over a follow-up period of 30 months. The probability of being free of both events at month 30 was 50.6% (95% CI: 40.0, 60.2). When patient characteristics and markers of disease severity were jointly examined in a multivariable analysis, oxygen use at rest (hazard ratio [HR] 2.44 [95% CI: 1.45, 4.10]), lower forced vital capacity (FVC) % predicted (HR 1.28 [95% CI: 1.10, 1.49] per 10% decrease) and diffusion capacity for carbon monoxide (DLco) % predicted (HR 1.25 [95% CI: 1.04, 1.51] per 10% decrease) were significantly associated with increased risk of death or lung transplant. The risk of death or lung transplant increased with increasing age in patients ≥62 years old (HR 1.18 [95% CI: 0.99, 1.40] per 5-year increase), and decreased with increasing age in patients <62 years old (HR 0.60 [95% CI: 0.39, 0.92] per 5-year increase).

Conclusions

In an observational US registry of patients with IPF, oxygen use at rest, lower FVC % predicted, and lower DLco % predicted were associated with risk of death or lung transplant. An audio podcast of the lead author discussing these data can be downloaded from: http://www.usscicomms.com/respiratory/snyder/IPF-PROsurvival1/.

Trial registration

ClinicalTrials.gov number: NCT01915511.

Electronic supplementary material

The online version of this article (10.1186/s12931-019-1043-9) contains supplementary material, which is available to authorized users.

Sensitization in Transplantation: Assessment of Risk (STAR) 2017 Working Group Meeting Report

The presence of preexisting (memory) or de novo donor-specific HLA antibodies (DSAs) is a known barrier to successful long-term organ transplantation. Yet, despite the fact that laboratory tools and our understanding of histocompatibility have advanced significantly in recent years, the criteria to define presence of a DSA and assign a level of risk for a given DSA vary markedly between centers. A collaborative effort between the American Society for Histocompatibility and Immunogenetics and the American Society of Transplantation provided the logistical support for generating a dedicated multidisciplinary working group, which included experts in histocompatibility as well as kidney, liver, heart, and lung transplantation. The goals were to perform a critical review of biologically driven, state-of-the-art, clinical diagnostics literature and to provide clinical practice recommendations based on expert assessment of quality and strength of evidence. The results of the Sensitization in Transplantation: Assessment of Risk (STAR) meeting are summarized here, providing recommendations on the definition and utilization of HLA diagnostic testing, and a framework for clinical assessment of risk for a memory or a primary alloimmune response. The definitions, recommendations, risk framework, and highlighted gaps in knowledge are intended to spur research that will inform the next STAR Working Group meeting in 2019.

Adaptive behavior in autism: Minimal clinically important differences on the Vineland-II

Autism Spectrum Disorder (ASD) is associated with persistent impairments in adaptive abilities across multiple domains. These social, personal, and communicative impairments become increasingly pronounced with development, and are present regardless of IQ. The Vineland Adaptive Behavior Scales, Second Edition (Vineland-II) is the most commonly used instrument for quantifying these impairments, but minimal clinically important differences (MCIDs) on Vineland-II scores have not been rigorously established in ASD. We pooled data from several consortia/registries (EU-AIMS LEAP study, ABIDE-I, ABIDE-II, INFOR, Simons Simplex Collection and Autism Treatment Network [ATN]) and clinical investigations and trials (Stanford, Yale, Roche) resulting in a data set of over 9,000 individuals with ASD. Two approaches were used to estimate MCIDs: distribution-based methods and anchor-based methods. Distribution-based MCID [d-MCID] estimates included the standard error of the measurement, as well as one-fifth and one-half of the covariate-adjusted standard deviation (both cross-sectionally and longitudinally). Anchor-based MCID [a-MCID] estimates include the slope of linear regression of clinician ratings of severity on the Vineland-II score, the slope of linear regression of clinician ratings of longitudinal improvement category on Vineland-II change, the Vineland-II change score maximally differentiating clinical impressions of minimal versus no improvement, and equipercentile equating. Across strata, the Vineland-II Adaptive Behavior Composite standardized score MCID estimates range from 2.01 to 3.2 for distribution-based methods, and from 2.42 to 3.75 for sample-size-weighted anchor-based methods. Lower Vineland-II standardized score MCID estimates were observed for younger and more cognitively impaired populations. These MCID estimates enable users of Vineland-II to assess both the statistical and clinical significance of any observed change. Autism Res 2018, 11: 270-283. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

LAY SUMMARY

The Vineland Adaptive Behavior Scales (2nd edition; Vineland-II) is the most widely used scale for assessing day-to-day "adaptive" skills. Yet, it is unknown how much Vineland-II scores must change for those changes to be regarded as clinically significant. We pooled data from over 9,000 individuals with ASD to show that changes of 2-3.75 points on the Vineland-II Composite score represent the "minimal clinically-important difference." These estimates will help evaluate the benefits of potential new treatments for ASD.

Patterns and predictors of pain following lung transplantation

OBJECTIVE

Our objective was to examine variability in pain levels following lung transplantation, and examine individual biopsychosocial factors influencing changes in pain.

METHOD

We performed a retrospective study of a cohort of 150 patients transplanted and discharged from Duke University Hospital between January 2015 and September 2016. During hospitalization and at clinic visits up to two months after discharge, subjective pain ratings were obtained using a 0-10 Numeric Rating Scale. Psychiatric diagnoses of anxiety and depression and Center for Epidemiological Studies - Depression (CES-D) scores collected after hospital discharge were examined as predictors of post-surgery pain. Medical and surgical variables were examined as covariates.

RESULTS

During hospitalization, pain ratings decreased over time (p<0.001). Predictors of higher pain levels included pre-transplant history of depression (p=0.001) and anxiety (p=0.04), bilateral lung transplant (p=0.03), and lower six-minute walk distance (p=0.02). Two months after discharge, 18% of patients reported continued pain and 34% remained on opioid pain medications. Two months after discharge, more frequent post-operative complications predicted higher pain levels in a univariate analysis (p=0.02) although this relationship was attenuated after adjustment for depression. In a multivariate analysis, elevated CES-D scores (p=0.002), and greater opioid use (p=0.031) predicted higher pain levels 2-months post-discharge.

CONCLUSION

We conclude that patients with psychiatric comorbidities may be at risk for greater pain, and may require additional strategies for more effective pain management.

Effect of HMG CoA reductase inhibitors on the development of chronic lung allograft dysfunction

Lung transplant recipients (LRs) have a reduced median 5-year survival of approximately 55% primarily due to chronic lung allograft dysfunction (CLAD). Statins have anti-inflammatory and immunomodulatory effects that may facilitate CLAD prevention. This study sought to evaluate statin effect on CLAD development. Adult bilateral LRs from January 2004 to October 2013 were included. Statin group included recipients with early statin use and continued for minimum 6 months. Propensity score matching was performed for age, gender, and native lung disease to select matched nonstatin group. Competing risk approach was used to evaluate statin effect on CLAD development at 3 years while controlling for acute rejection and CMV pneumonitis. A total of 130 patients were included in each group. CLAD cumulative incidence at 3 years for statin and nonstatin groups was 20.6% (CI: 11.8%-33.5%) and 22.4% (CI: 12.2%-27.3%). Statin use was not associated with a decreased risk of CLAD (subdistribution hazard ratio [SHR]: 0.93, 95% CI: 0.55-1.59, P = .80) but was associated with a decreased risk of death (SHR: 0.45, CI: 0.22-0.90, P = .024). At 3 years, patient survival was 81.7% in statin group and 68.3% in nonstatin group (P = .012). Statins did not significantly delay the time to development of CLAD in LR but did demonstrate a benefit in patient survival.

Human Leukocyte Antigen Sensitization in Solid Organ Transplantation: A Primer on Terminology, Testing, and Clinical Significance for the Apheresis Practitioner

The human leukocyte antigen (HLA) system is an important immunologic barrier that must be considered for successful solid organ transplantation. Formation of donor-specific HLA antibodies in solid organ transplantation is an important cause of allograft injury and may contribute to recipient morbidity and mortality. Therapeutic plasma exchange is often requested to lower HLA antibody levels prior to or after transplantation and for management of HLA antibodies in the context of organ rejection. In this review, we summarize the current terminology, laboratory testing, and clinical significance of HLA sensitization in the solid organ transplant population. Furthermore, to illustrate applications of HLA testing in clinical practice, we summarize our own lung and kidney institutional protocols for managing HLA antibodies in the peri-transplant setting.

Incidence of acute cellular rejection following granulocyte colony-stimulating factor administration in lung transplantation: A retrospective case-cohort analysis

Granulocyte colony-stimulating factor (GCSF) is an option to treat leukopenia in lung transplant recipients. Conflicting evidence exists regarding its effects on acute cellular rejection (ACR). A retrospective, case-cohort study was conducted to assess whether the use of GCSF in lung transplant recipients is associated with an increased incidence of ACR. Patients had to have received at least one dose of GCSF but were excluded if they received GCSF within 30 days prior to transplant or received a lymphocyte-depleting agent within 14 days of GCSF administration. Thirty-five patients who received GCSF within 3 months of transplant met inclusion criteria and 105 patients were identified as controls based on a 1:3 allocation scheme. Incidence of ACR was 57.1% in the GCSF group versus 50.5% in the control group (relative risk (RR)=1.13; 95% CI, 0.80 to 1.59; P=.48). At 3 months post-transplant, 74.3% of the GCSF group had a dose reduction or discontinuation of their antiproliferative agent versus 17.1% of the control group (RR=4.33; 95% CI, 2.73 to 6.89; P<.0001). Rejection severity and incidence of infections was similar among groups. These findings show that GCSF administration within 3 months following lung transplantation was not associated with a higher incidence or severity of ACR.

The utility of 6-minute walk distance in predicting waitlist mortality for lung transplant candidates

BACKGROUND

The lung allocation score (LAS) has led to improved organ allocation for transplant candidates. At present, the 6-minute walk distance (6MWD) is treated as a binary categorical variable of whether or not a candidate can walk more than 150 feet in 6 minutes. In this study, we tested the hypothesis that 6MWD is presently under-utilized with respect to discriminatory power, and that, as a continuous variable, could better prognosticate risk of waitlist mortality.

METHODS

A retrospective cohort analysis was performed using the Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) transplant database. Candidates listed for isolated lung transplant between May 2005 and December 2011 were included. The population was stratified by 6MWD quartiles and unadjusted survival rates were estimated. Multivariable Cox proportional hazards modeling was used to assess the effect of 6MWD on risk of death. The Scientific Registry of Transplant Recipients (SRTR) Waitlist Risk Model was used to adjust for confounders. The optimal 6MWD for discriminative accuracy in predicting waitlist mortality was assessed by receiver-operating characteristic (ROC) curves.

RESULTS

Analysis was performed on 12,298 recipients. Recipients were segregated into quartiles by distance walked. Waitlist mortality decreased as 6MWD increased. In the multivariable model, significant variables included 6MWD, male gender, non-white ethnicity and restrictive lung diseases. ROC curves discriminated 6-month mortality was best at 655 feet.

CONCLUSIONS

The 6MWD is a significant predictor of waitlist mortality. A cut-off of 150 feet sub-optimally identifies candidates with increased risk of mortality. A cut-off between 550 and 655 feet is more optimal if 6MWD is to be treated as a dichotomous variable. Utilization of the LAS as a continuous variable could further enhance predictive capabilities.

Parasaccharibacter apium, gen. nov., sp. nov., Improves Honey Bee (Hymenoptera: Apidae) Resistance to Nosema

The honey bee, Apis mellifera L., is host to a variety of microorganisms. The bacterial community that occupies the adult worker gut contains a core group of approximately seven taxa, while the hive environment contains its own distribution of bacteria that is in many ways distinct from the gut. Parasaccharibacter apium, gen. nov., sp. nov., is a hive bacterium found in food stores and in larvae, worker jelly, worker hypopharyngeal glands, and queens. Parasaccharibacter apium increases larval survival under laboratory conditions. To determine if this benefit is extended to colonies in the field, we tested if P. apium 1) survives and reproduces in supplemental pollen patty, 2) is distributed throughout the hive when added to pollen patty, 3) benefits colony health, and 4) increases the ability of bees to resist Nosema. Parasaccharibacter apium survived in supplemental diet and was readily consumed by bees. It was distributed throughout the hive under field conditions, moving from the pollen patty to hive larvae. While P. apium did not significantly increase colony brood production, food stores, or foraging rates, it did increase resistance to Nosema infection. Our data suggest that P. apium may positively impact honey bee health.

The relationship between plasma lipid peroxidation products and primary graft dysfunction after lung transplantation is modified by donor smoking and reperfusion hyperoxia

BACKGROUND

Donor smoking history and higher fraction of inspired oxygen (FIO2) at reperfusion are associated with primary graft dysfunction (PGD) after lung transplantation. We hypothesized that oxidative injury biomarkers would be elevated in PGD, with higher levels associated with donor exposure to cigarette smoke and recipient hyperoxia at reperfusion.

METHODS

We performed a nested case-control study of 72 lung transplant recipients from the Lung Transplant Outcomes Group cohort. Using mass spectroscopy, F2-isoprostanes and isofurans were measured in plasma collected after transplantation. Cases were defined in 2 ways: grade 3 PGD present at day 2 or day 3 after reperfusion (severe PGD) or any grade 3 PGD (any PGD).

RESULTS

There were 31 severe PGD cases with 41 controls and 35 any PGD cases with 37 controls. Plasma F2-isoprostane levels were higher in severe PGD cases compared with controls (28.6 pg/ml vs 19.8 pg/ml, p = 0.03). Plasma F2-isoprostane levels were higher in severe PGD cases compared with controls (29.6 pg/ml vs 19.0 pg/ml, p = 0.03) among patients reperfused with FIO2 >40%. Among recipients of lungs from donors with smoke exposure, plasma F2-isoprostane (38.2 pg/ml vs 22.5 pg/ml, p = 0.046) and isofuran (66.9 pg/ml vs 34.6 pg/ml, p = 0.046) levels were higher in severe PGD compared with control subjects.

CONCLUSIONS

Plasma levels of lipid peroxidation products are higher in patients with severe PGD, in recipients of lungs from donors with smoke exposure, and in recipients exposed to higher Fio2 at reperfusion. Oxidative injury is an important mechanism of PGD and may be magnified by donor exposure to cigarette smoke and hyperoxia at reperfusion.

Neutralizing CCL2 Inhibits Breast Tumor Growth Via Impact on the Tumor/Stroma Microenvironment

CCL2, (CC-chemokine ligand 2 or monocyte chemoattractant protein-1 (MCP-1)), is overexpressed in many human tumors and is believed to exert pro-tumor effects by recruiting monocytes to the tumor, where these cells become tumor associated macrophages (TAMs). TAMs secrete growth factors that stimulate angiogenesis and tumor growth, as well as proteases to promote tumor invasion and metastasis. CCL2 expression levels in primary breast tumors have been correlated with macrophage infiltration and blood vessel density, which in turn is correlated with disease stage and prognosis. These correlations indicate that CCL2 is a key player in tumor macrophage infiltration and/or tumor growth/invasion, and suggest that neutralizing CCL2 could be an effective form of therapy for breast cancer patients.The objective of these studies was to investigate whether CCL2 blockade could inhibit tumor growth in mice bearing human breast tumors. The human breast tumor cell lines MDA-MB-231 (ER-, PR-, Her2-) and MDA-MB-361 (ER+, PR+, Her2+) were implanted orthotopically in immunocompromised mice, and in both models the primary tumors metastasized to lungs and brain. Neutralizing antibodies to human CCL2 (CNTO 888) and to the mouse orthologs, MCP-1 and MCP-5, were administered therapeutically, either as a cocktail (termed CCL2 blockade) or individually to study the relative roles of host vs tumor derived CCL2 in promoting tumor growth.In both tumor models, CCL2 blockade significantly inhibited the growth of established primary tumors in the mammary fat pad. In addition, CCL2 blockade inhibited metastasis to distant sites. As measured by Taqman, visual inspection and immunohistochemistry, mice with MDA-MB-361 tumors treated with CCL2 blockade showed significantly reduced metastasis to lungs and brain, while mice bearing MDA-MB-231 tumors showed significantly reduced metastasis to lungs.To define the relative roles of human tumor-derived CCL2 vs mouse host-derived MCP-1/MCP-5, in vivo monotherapy tumor studies were conducted using the individual neutralizing antibodies. These studies included the mammary fat pad model and a tail vein metastasis model. In both cases, only the treatment with the anti-mouse MCP-1 antibody significantly inhibited primary tumor growth and distant metastasis, indistinguishable from the effect of CCL2 blockade treatment. In the tail vein metastasis model, the antibody treatment resulted in significantly fewer detectable lesions with these lesions showing a significant reduction in both tumor size and growth fraction, suggesting antibody treatment inhibits tumor seeding and growth. Mechanistic studies are in progress to further understand the basis of the anti-tumor effect mediated by the antibody treatment. These results demonstrate that host-derived MCP-1, produced from the tumor microenvironment, plays the critical role in tumor growth and metastasis in these models of human breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6095.

Leukotriene modifier use and asthma severity: how is a new medication being used by adults with asthma?

BACKGROUND

The introduction of leukotriene modifiers, the first novel class of medications for asthma in more than 2 decades, provided an opportunity to evaluate the clinical context in which patients receive new treatments. Because milder asthma is usually controllable with more familiar medications, we hypothesized that adults with asthma would receive leukotriene modifiers for more severe disease.

METHODS

We conducted a prospective, longitudinal, 18-month cohort study of 349 patients with asthma. We evaluated the association of baseline self-reported medication use and measures of asthma severity. We also examined the impact of baseline measurement of asthma severity on incident leukotriene modifier use at follow-up.

RESULTS

At baseline, 39 (11%) of 349 patients reported leukotriene modifier use during the previous 2 weeks (95% confidence interval [CI], 8%-15%). Adults with asthma who reported recent use of leukotriene modifiers were more likely to indicate use of other long-term controller medications for asthma, such as inhaled corticosteroids (80% vs 57%;P =.007). Leukotriene modifier use was also associated with poorer severity-of-asthma scores (mean score difference, 3.6 points; 95% CI, 1.7-5.2 points) and asthma-specific health-related quality of life (mean score difference, 8.1 points; 95% CI, 3.4-12.8 points). Leukotriene modifier users were also more likely to indicate a recent emergency department visit (odds ratio [OR], 2.3; 95% CI, 0.9-5.6) or hospitalization for asthma (OR, 4.1; 95% CI, 1.4-11.4). Greater baseline asthma severity was associated with an increased probability of new-onset leukotriene modifier use during 18-month follow-up. Poorer baseline severity-of-asthma scores and asthma-specific quality-of-life scores were related to a greater likelihood of leukotriene modifier use at follow-up (OR per SD-sized score increment, 2.0; 95% CI, 1.4-2.7; OR, 1.8; 95% CI, 1.3-2.5; respectively). Recent hospitalization for asthma at baseline was also associated with a greater likelihood of leukotriene modifier use at follow-up (OR, 4.9; 95% CI, 1.6-14.8).

CONCLUSIONS

Adults with asthma who receive leukotriene modifiers have more severe asthma.

Health-related quality of life assessment in adult haemophilia patients: a systematic review and evaluation of instruments

The objective of this study was to review and evaluate the performance of health-related quality of life (HRQL) and other health status measures used in studies of adult haemophilia and provide recommendations for future research. A systematic literature review was performed to identify HRQL and health status measures used in haemophilia. Literature was identified using medical databases, Internet and manual searches. The search was restricted to articles published in English since 1986. Ninety-six abstracts were located; 19 relevant articles were selected for detailed review. Three main types of HRQL measures were identified: generic psychometric-based HRQL (SF-36 and SF-12), utility-based HRQL [EQ-5D and Health Utilities Index (HUI)], and musculoskeletal-specific HRQL (Arthritis Impact Measurement Scale 2, AIMS 2) instruments. No patient-rated haemophilia-specific HRQL instrument was found. The SF-36, the EQ-5D, and the HUI were able to discriminate haemophilia patient subgroups with respect to disease severity and HIV comorbidity status. Sixteen additional scales were identified that were used to measure the different aspects of physical, psychological, and social functioning of patients. There were no clinical studies of haemophilia carried out that employed HRQL instruments, thus responsiveness of these instruments could not be evaluated. The variety of instruments used in haemophilia studies highlights the need for a tool that can capture the full impact of haemophilia and its treatment on patients' HRQL. Developing such a tool poses the unique challenge of accounting for common comorbidities, such as HIV and chronic hepatitis that may have a greater HRQL impact than the underlying disease.

Physician-assisted suicide

Medical professional codes have long prohibited physician involvement in assisting a patient's suicide. However, despite ethical and legal prohibitions, calls for the liberalization of this ban have grown in recent years. The medical profession should articulate its views on the arguments for and against changes in public policy and decide whether changes are prudent. In addressing such a contentious issue, physicians, policymakers, and society must fully consider the needs of patients, the vulnerability of particular patient groups, issues of trust and professionalism, and the complexities of end-of-life health care. Physician-assisted suicide is prominent among the issues that define our professional norms and codes of ethics. The American College of Physicians-American Society of Internal Medicine (ACP-ASIM) does not support the legalization of physician-assisted suicide. The routine practice of physician-assisted suicide raises serious ethical and other concerns. Legalization would undermine the patient-physician relationship and the trust necessary to sustain it; alter the medical profession's role in society; and endanger the value our society places on life, especially on the lives of disabled, incompetent, and vulnerable individuals. The ACP-ASIM remains thoroughly committed to improving care for patients at the end of life.