A longitudinal study of serum insulin and insulin resistance as predictors of weight and body fat gain in African American and Caucasian children

BACKGROUND

The influence of insulin and insulin resistance (IR) on children's weight and fat gain is unclear.

OBJECTIVE

To evaluate insulin and IR as predictors of weight and body fat gain in children at high risk for adult obesity. We hypothesized that baseline IR would be positively associated with follow-up body mass index (BMI) and fat mass.

SUBJECTS/METHODS

Two hundred and forty-nine healthy African American and Caucasian children aged 6-12 years at high risk for adult obesity because of early-onset childhood overweight and/or parental overweight were followed for up to 15 years with repeated BMI and fat mass measurements. We examined baseline serum insulin and homeostasis model of assessment-IR (HOMA-IR) as predictors of follow-up BMI Z-score and fat mass by dual-energy X-ray absorptiometry in mixed model longitudinal analyses accounting for baseline body composition, pubertal stage, sociodemographic factors and follow-up interval.

RESULTS

At baseline, 39% were obese (BMI⩾95th percentile for age/sex). Data from 1335 annual visits were examined. Children were followed for an average of 7.2±4.3 years, with a maximum follow-up of 15 years. After accounting for covariates, neither baseline insulin nor HOMA-IR was significantly associated with follow-up BMI (Ps>0.26), BMIz score (Ps>0.22), fat mass (Ps>0.78) or fat mass percentage (Ps>0.71). In all models, baseline BMI (P<0.0001), body fat mass (P<0.0001) and percentage of fat (P<0.001) were strong positive predictors for change in BMI and fat mass. In models restricted to children without obesity at baseline, some but not all models had significant interaction terms between body adiposity and insulinemia/HOMA-IR that suggested less gain in mass among those with greater insulin or IR. The opposite was found in some models restricted to children with obesity at baseline.

CONCLUSIONS

In middle childhood, BMI and fat mass, but not insulin or IR, are strong predictors of children's gains in BMI and fat mass during adolescence.

Clinical response, drug survival, and predictors thereof among 548 patients with psoriatic arthritis who switched tumor necrosis factor α inhibitor therapy: results from the Danish Nationwide DANBIO Registry

OBJECTIVE

To describe the frequency of treatment switching and outcomes among patients with psoriatic arthritis (PsA) who switched tumor necrosis factor α inhibitor (TNFi) agents in routine care.

METHODS

We conducted an observational cohort study based on the Danish nationwide DANBIO registry. Treatment outcomes were evaluated using the American College of Rheumatology criteria for 20% improvement (ACR20)/ACR50/ACR70, European League Against Rheumatism (EULAR) response criteria for good response, and the 28-joint count Disease Activity Score (DAS28) (remission). Kaplan-Meier and regression analyses were used for drug survival analyses and to identify predictors of outcome after treatment switching.

RESULTS

Of 1,422 patients starting TNFi agents, 548 patients (39%) switched to a second biologic drug during up to 10 years of followup. Median followup was 2.3 years (interquartile range [IQR] 1.0-4.3 years). Switchers were more frequently women (56% versus 45%), had a shorter disease duration (3 versus 4 years), a higher median Health Assessment Questionnaire (HAQ) score (1.1 [IQR 0.6-1.6] versus 0.9 [IQR 0.5-1.4]), DAS28 (4.8 [4.0-5.7] versus 4.4 [3.6-5.2]), pain score on a visual analog scale (VAS) (65 mm [46-77] versus 62 mm [40-75]), and fatigue score on a VAS (69 mm [50-83] versus 64 mm [42-80] mm) (all P < 0.05 at start of first TNFi). During the first and second treatment, HAQ, DAS28, and VAS scores and C-reactive protein levels had decreased after 6 months (all P < 0.05), and median drug survival was 2.2 versus 1.3 years (P < 0.001). Lower fatigue score increased survival of the second TNFi. After switching, the proportions of patients achieving a sustained ACR20, ACR50, ACR70, EULAR good response, and DAS28 remission after 3-6 months were 22% (number needed to treat [NNT] 4.5), 13% (NNT 7.9), 5% (NNT 20), 19% (NNT 5.3), and 34% (NNT 2.9), respectively. Response rates were lower during the second treatment (all P < 0.01 versus first TNFi). At the 2-year visit, 47% of switchers had achieved an ACR20 response. No differences between drug-drug combinations were found.

CONCLUSION

Thirty-nine percent of the patients with PsA switched TNFi agents. Response rates and drug survival were lower after switching; however, half of the switchers had an ACR20 response 2 years after starting the first TNFi.

An evaluation of the completeness and accuracy of active tuberculosis reporting in the United States military

SETTING

Despite the low incidence of tuberculosis (TB) in the United States military, there is uncertainty in the overall reporting and estimates of incidence.

OBJECTIVE

To assess TB reporting in the active component US military.

DESIGN

TB notification in the US military was compared with three other data sources: laboratory, hospitalization and pharmacy records. Sensitivity and positive predictive value were estimated for all data sources using a gold standard of either a reportable medical event (RME) reported as confirmed or a positive laboratory result for Mycobacterium tuberculosis. Uncorrected and capture-recapture (CR) methods were used to estimate underreporting and completeness of data sources.

RESULTS

Completeness of reporting of pulmonary TB cases was estimated as 72.4% uncorrected or 58.3% with CR. Even after correction for possible underreporting, the incidence of active pulmonary TB was only 0.87 per 100,000 person-years between 2004 and 2006.

CONCLUSION

The rate of active TB in the US military is low. Like civilian surveillance, US military RME surveillance may substantially underreport TB incidence rates. Expanding surveillance to include data sources such as hospitalizations and pharmacy records will increase the number of TB diagnoses at the cost of including many false-positives.

Modafinil for treatment of fatigue in post-polio syndrome: a randomized controlled trial

OBJECTIVE

To determine if modafinil can improve fatigue in patients with post-polio syndrome.

METHODS

We used a randomized, placebo-controlled crossover trial. Intervention with modafinil (400 mg/day) and placebo occurred over 6-week periods. Primary endpoint (fatigue) was assessed using the Fatigue Severity Scale as the main outcome measure. Other measures included the Visual Analog Scale for Fatigue and the Fatigue Impact Scale. Secondary endpoint (health-related quality of life) was assessed using the 36-Item Short-Form. Analysis of variance for repeated measures was applied to assess treatment, period, and carryover effects.

RESULTS

Thirty-six patients were randomized, 33 of whom (mean age: 61 years) completed required interventions. Treatment with modafinil was safe and well-tolerated. After adjusting for periods and order effects, no difference was observed between treatments.

CONCLUSION

Based on the utilized measures of outcome modafinil was not superior to placebo in alleviating fatigue or improving quality of life in the studied post-polio syndrome population.

Thymidine Analogue Mutation Profiles: Factors Associated with Acquiring Specific Profiles and their Impact on the Virological Response to Therapy

Background

Studies have suggested that HIV-1 may develop thymidine analogue mutations (TAMs) by one of two distinct pathways – the TAM1 pathway (including mutations 41L, 210W and 215Y) or the TAM2 pathway (including mutations 67N, 70R and 219E/Q) – under the pressure of a not fully suppressive thymidine-analogue-containing regimen.

Methods

Frozen plasma samples stored in the EuroSIDA repository were selected and sent to two central laboratories for genotypic analysis. We considered 733 patients with at least one genotypic test showing ≥1 TAMs (the first of these tests in chronological order was used). TAM1 and TAM2 genotypic profiles were defined in accordance with previous literature. Statistical modelling involved logistic regression and linear regression analysis for censored data.

Results

The observed frequencies of patterns classifiable as TAM1 or TAM2 profiles were markedly higher than the probabilities of falling into these classifications by chance alone. The chance of detecting a TAM2 profile increased by 25% per additional year of exposure to zidovudine. We found that mutations 67N and 184V were not associated with a particular TAM profile. In the presence of TAM2 profiles, the adjusted mean difference in the 6-month viral reduction was 0.96 log10 copies/ml (95% confidence interval: 0.20; 1.73) higher in patients who started stavudine-containing regimens instead of zidovudine-containing regimens.

Conclusions

This study provides evidence that the suggested TAM clustering is a real phenomenon and that it may be driven by which thymidine analogue the patients has used. In patients with TAM2-resistant viruses, stavudine appears to retain greater viral activity than zidovudine.

Risk of AIDS and death at given HIV-RNA and CD4 cell count, in relation to specific antiretroviral drugs in the regimen

BACKGROUND

It is unknown whether the relationship between the HIV-RNA/CD4 cell count and risk of clinical disease continues to hold true for newer antiretroviral drugs approved without data from clinical endpoint trials.

OBJECTIVE

: To determine and compare whether rate ratios of AIDS and death at given, latest HIV-RNA and CD4 cell counts levels were similar, regardless of which nucleoside pair and specific third drugs patients received as antiretroviral therapy.

DESIGN

EuroSIDA observational cohort. A total of 9802 prospectively followed patients.

METHODS

Analysis included patients taking combination antiretroviral therapy (CART) regimens containing two non-abacavir nucleosides plus a 'third drug' of a non-nucleoside reverse transcriptase inhibitor, a (possibly ritonavir boosted) protease inhibitor or abacavir.

RESULTS

A total of 6814 patients contributed a total of 22 766.6 person-years of follow up. Median latest CD4 cell count was 353 x 10 cells/l, HIV-RNA 199 copies/ml. A total of 900 events of new AIDS or death were observed. AIDS/death rates for any given CD4 or HIV-RNA category were similar regardless of specific drugs being used. Adjusted rate ratios (RR) for individual drugs compared with indinavir (for which clinical endpoint trials are available) were all close to 1 and with relatively narrow 95% confidence intervals (CI); for example, nelfinavir RR, 0.99 (95% CI, 0.76-1.28); efavirenz RR, 0.83 (95% CI, 0.57-1.20); abacavir RR, 1.01 (95% CI, 0.64-1.60). Results were similar for different nucleoside pairs.

CONCLUSIONS

The results indicate that AIDS/death rates for given CD4 cell count and HIV-RNA categories are similar, regardless of CART regimen being taken and provide reassurance that HIV-RNA and CD4 cell counts in individual patients receiving newer drugs have the same meaning, in terms of AIDS/death risk, regardless of specific antiretroviral regimen.

Electrical amygdala kindling in alcohol-withdrawal kindled rats

Repeated alcohol withdrawal has been shown to kindle seizure activity. The purpose of the present investigation was to study electrical amygdala kindling in rats previously exposed to alcohol-withdrawal kindling. In three independent experiments, male Wistar rats were subjected to multiple episodes each consisting of 2 days of severe alcohol intoxication and 5 days of alcohol withdrawal. In the first experiment, the alcohol-withdrawal kindled animals were divided into two groups depending on whether spontaneous alcohol-withdrawal seizures were observed in episodes 10-13. In the second and third experiments, the alcohol-withdrawal kindled animals were compared to a group in which alcohol-withdrawal kindling was prevented by diazepam treatment during the withdrawal reactions in order to discriminate between the effect of withdrawal and intoxication. Electrical kindling was initiated 28-35 days after the last alcohol dose by exposing the animals to daily electrical stimulations of the right amygdala. The results showed that amygdala kindling was facilitated in alcohol-withdrawal kindled animals which showed spontaneous withdrawal seizure activity, compared with animals exposed to multiple episodes of alcohol withdrawal which did not develop withdrawal seizures or with animals exposed to a single episode of alcohol intoxication. When compared to the control group, the alcohol-withdrawal kindled group with seizures also kindled at a faster rate, but the difference did not reach statistical significance and therefore the results must be regarded as preliminary at present.

Serotonin1A receptor autoradiography during alcohol-withdrawal kindling

A series of autoradiography experiments were conducted in order to test the theory that the serotonin (5-HT) receptor subtype 5-HT(1a) is involved in alcohol-withdrawal kindled convulsive behaviour. Alcohol-withdrawal kindling was performed by subjecting male Wistar rats to multiple episodes consisting of 2 days of alcohol intoxication and 5 days of alcohol withdrawal. In the first episode alcohol intoxication led to focal downregulation of [3H]-8-hydroxy-2-(di-n-propylamino)tetralin ([3H]-8-OH-DPAT) binding sites in septum and subregions of frontal cortex, hippocampus, and entorhinal cortex. This alcohol-induced response was blunted in both alcohol-withdrawal kindled animals and in animals exposed to repeated alcohol dependence in which the previous withdrawal reactions were blocked by diazepam administration. A paradoxical upregulation of [3H]-8-OH-DPAT binding sites was found in septum and subregions of frontal cortex, hippocampus, and entorhinal cortex in control animals which were fed isocalorically with the alcohol-withdrawal kindled animals and subsequently exposed to 2 days of alcohol intoxication. It was concluded that the alterations in the alcohol induced 5-HT(1a) receptor regulation after multiple episodes of alcohol dependence were not caused by alcohol-withdrawal kindling processes per se, but were due to both alcohol specific and alcohol non-specific effects.

No loss of somatostatin-immunoreactive neurons in the hippocampal dentate hilus of alcohol-withdrawal-kindled rats

The neuropeptide somatostatin has been suggested to play a role in seizure genesis, electrical kindling and the neurotoxic effects of alcohol. The purpose of the present experiment was to study somatostatin-immunoreactive (SS-IR) neurons in hippocampus during alcohol-withdrawal kindling. Alcohol-withdrawal kindling was performed by subjecting male Wistar rats to seven weekly episodes consisting of 2 days of severe alcohol intoxication and 5 days of alcohol withdrawal. Then the kindled animals (multiple withdrawal group) and a single withdrawal group, which was fed isocalorically with the kindled animals during episodes 1-7, were exposed to 4 days of severe alcohol intoxication (episode 8). During the following withdrawal, the seizure activity was observed 9-15 h after last alcohol dose, in order to subdivide the animals from these two groups into groups with and without seizures. Subsequently, SS-IR neurons were visualized immunocytochemically and counted in the hilus of the dentate gyrus (hippocampus). The number of SS-IR neurons per unit area of the hilus was neither affected by a single nor by multiple episodes of alcohol withdrawal. We therefore concluded that a loss of these neurons is not involved in the development of alcohol-withdrawal-kindled seizures.