Publications

The cutaneous permeability barrier is essential for life and perturbations in this barrier are repaired rapidly. After minimal injury to the stratum corneum alterations in the calcium concentration in the outer epidermis are the primary signal inducing this repair response. In this issue, studies demonstrate that Toll-like receptor 3 has an important role in signaling permeability barrier repair following injury induced by UVB irradiation.

The American Thoracic Society (ATS), in collaboration with George Mason University, surveyed a random sample of ATS members to assess their perceptions of, clinical experiences with, and preferred policy responses to climate change. An e-mail containing an invitation from the ATS President and a link to an online survey was sent to 5,500 randomly selected U.S. members; up to four reminder e-mails were sent to nonrespondents. Responses were received from members in 49 states and the District of Columbia (n = 915); the response rate was 17%. Geographic distribution of respondents mirrored that of the sample. Survey estimates' confidence intervals were ±3.5% or smaller. Results indicate that a large majority of ATS members have concluded that climate change is happening (89%), that it is driven by human activity (68%), and that it is relevant to patient care ("a great deal"/"a moderate amount") (65%). A majority of respondents indicated they were already observing health impacts of climate change among their patients, most commonly as increases in chronic disease severity from air pollution (77%), allergic symptoms from exposure to plants or mold (58%), and severe weather injuries (57%). A larger majority anticipated seeing these climate-related health impacts in the next 2 decades. Respondents indicated that physicians and physician organizations should play an active role in educating patients, the public, and policy makers on the human health effects of climate change. Overall, ATS members are observing that human health is already adversely affected by climate change and support responses to address this situation.

BACKGROUND

Even among HIV-infected patients who fully suppress plasma HIV RNA replication on antiretroviral therapy, genetic (e.g. CCL3L1 copy number), viral (e.g. tropism) and environmental (e.g. chronic exposure to microbial antigens) factors influence CD4 recovery. These factors differ markedly around the world and therefore the expected CD4 recovery during HIV RNA suppression may differ globally.

METHODS

We evaluated HIV-infected adults from North America, West Africa, East Africa, Southern Africa and Asia starting non-nucleoside reverse transcriptase inhibitorbased regimens containing efavirenz or nevirapine, who achieved at least one HIV RNA level <500/ml in the first year of therapy and observed CD4 changes during HIV RNA suppression. We used a piecewise linear regression to estimate the influence of region of residence on CD4 recovery, adjusting for socio-demographic and clinical characteristics. We observed 28 217 patients from 105 cohorts over 37 825 person-years.

RESULTS

After adjustment, patients from East Africa showed diminished CD4 recovery as compared with other regions. Three years after antiretroviral therapy initiation, the mean CD4 count for a prototypical patient with a pre-therapy CD4 count of 150/ml was 529/ml [95% confidence interval (CI): 517–541] in North America, 494/ml (95% CI: 429–559) in West Africa, 515/ml (95% CI: 508–522) in Southern Africa, 503/ml (95% CI: 478–528) in Asia and 437/ml (95% CI: 425–449) in East Africa.

CONCLUSIONS

CD4 recovery during HIV RNA suppression is diminished in East Africa as compared with other regions of the world, and observed differences are large enough to potentially influence clinical outcomes. Epidemiological analyses on a global scale can identify macroscopic effects unobservable at the clinical, national or individual regional level.

PURPOSE

We tested whether short-term vitamin D supplementation improves insulin resistance in patients with kidney disease, a condition with little intrinsic vitamin D activity.

METHODS

PubMed, EMBASE and CENTRAL were searched for relevant observational studies and randomized clinical trials (RCTs). Random-effects models were employed for meta-analysis, and effect sizes were summarized as standardized mean difference (SMD) with 95% confidence intervals. Separate analyses were done for RCTs and non-randomized intervention studies (NRIS).

RESULTS

Seventeen studies (5 RCTs and 12 NRIS) were included. The meta-analysis population (n = 131) was mostly middle aged (40-50 years), male and non-diabetic, and on hemodialysis. The duration (4-12 weeks) and type of supplementation varied between studies. Among RCTs, compared to placebo, vitamin D supplementation was associated with significant decrease in fasting glucose [SMD -1.13, (-2.11 to -0.11)] and PTH levels [SMD -1.50, (-2.95 to -0.04)] but no difference in fasting insulin levels [SMD 1.32, (-0.15 to 2.79)]. Among NRIS, there was only a significant decrease in PTH levels [SMD -1.68, (-2.55 to -0.82)] between pre- and post-vitamin D treatment levels.

CONCLUSIONS

Short-term (4-12 weeks) supplementation with vitamin D is associated with lower fasting glucose levels in ESRD with no change in fasting insulin levels. However, the findings from this study are limited by the studies that were used in the meta-analysis, which were mostly small, used multiple different vitamin D compounds and dosing regimens, and had large heterogeneity, and funnel plots showed that there was a dearth of studies with null or negative finding. Therefore, larger RCTs need to be performed to answer this important clinical question.

CONTEXT

Cancer patients experience a broad range of physical and psychological symptoms as a result of their disease and its treatment. On average, these patients report 10 unrelieved and co-occurring symptoms.

OBJECTIVES

The aims were to determine if subgroups of oncology outpatients receiving active treatment (n = 582) could be identified based on their distinct experience with 13 commonly occurring symptoms; to determine whether these subgroups differed on select demographic and clinical characteristics; and to determine if these subgroups differed on quality of life (QOL) outcomes.

METHODS

Demographic, clinical, and symptom data from one Australian and two U.S. studies were combined. Latent class analysis was used to identify patient subgroups with distinct symptom experiences based on self-report data on symptom occurrence using the Memorial Symptom Assessment Scale.

RESULTS

Four distinct latent classes were identified (i.e., all low [28.0%], moderate physical and lower psych [26.3%], moderate physical and higher psych [25.4%], and all high [20.3%]). Age, gender, education, cancer diagnosis, and presence of metastatic disease differentiated among the latent classes. Patients in the all high class had the worst QOL scores.

CONCLUSION

Findings from this study confirm the large amount of interindividual variability in the symptom experience of oncology patients. The identification of demographic and clinical characteristics that place patients at risk for a higher symptom burden can be used to guide more aggressive and individualized symptom management interventions.