Publications

Executive cognitive and neurologic abnormalities are commonly seen in patients with a chronic inflammatory response syndrome (CIRS) acquired following exposure to the interior environment of water-damaged buildings (WDB), but a clear delineation of the physiologic or structural basis for these abnormalities has not been defined. Symptoms of affected patients routinely include headache, difficulty with recent memory, concentration, word finding, numbness, tingling, metallic taste and vertigo. Additionally, persistent proteomic abnormalities in inflammatory parameters that can alter permeability of the blood-brain barrier, such as C4a, TGFB1, MMP9 and VEGF, are notably present in cases of CIRS-WDB compared to controls, suggesting a consequent inflammatory injury to the central nervous system. Findings of gliotic areas in MRI scans in over 45% of CIRS-WDB cases compared to 5% of controls, as well as elevated lactate and depressed ratios of glutamate to glutamine, are regularly seen in MR spectroscopy of cases. This study used the volumetric software program NeuroQuant® (NQ) to determine specific brain structure volumes in consecutive patients (N=17) seen in a medical clinic specializing in inflammatory illness. Each of these patients presented for evaluation of an illness thought to be associated with exposure to WDB, and received an MRI that was evaluated by NQ. When compared to those of a medical control group (N=18), statistically significant differences in brain structure proportions were seen for patients in both hemispheres of two of the eleven brain regions analyzed; atrophy of the caudate nucleus and enlargement of the pallidum. In addition, the left amygdala and right forebrain were also enlarged. These volumetric abnormalities, in conjunction with concurrent abnormalities in inflammatory markers, suggest a model for structural brain injury in "mold illness" based on increased permeability of the blood-brain barrier due to chronic, systemic inflammation.

PURPOSE

Inhibition of the phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) pathway is associated with metabolic and immunologic perturbations that impact drug tolerability. Here, we studied whether PI3 kinase/mTOR pathway inhibitors are associated with greater metabolic impact and decreased tolerability in Asian patients.

METHODS

A retrospective analysis was conducted of consecutive patients with advanced malignancies treated on phase 1 trials of PI3K/mTOR inhibitors. Adverse events related to PI3K/mTOR inhibition, fasting plasma glucose (FPG), insulin, and c-peptide levels, hemoglobin A1c (HgbA1c), and T cell subsets were prospectively collected. Mann-Whitney and Chi-square tests were used to compare continuous and categorical variables, respectively, between Asian and Caucasian patients.

RESULTS

A total of 103 patients (31 Asian; 72 Caucasian) were treated consecutively across five clinical trials. Baseline age, gender distribution, and metabolic parameters were comparable with the exception of lower median body mass index (BMI) in Asian patients (23.0 vs. 24.8 kg/m(2), p = 0.024). There were no differences in drug tolerability, adherence, or duration of therapy. Asian patients experienced a higher incidence of grade ≥ 2 hyperglycemia (37.5 vs. 18.1%, p = 0.03), and greater increases in FPG, HgbA1c, and insulin resistance. No differences in incidence or severity of mucositis, rash, or pneumonitis were observed. Drug effects on neutrophils, lymphocytes, and T cell subsets were similar.

CONCLUSIONS

PI3K/mTOR inhibitors have greater glycemic impact in Asian patients, despite similar baseline metabolic parameters, comparable dose intensity, and a lower median BMI. Further studies are warranted to explore the mechanisms underlying these differences and optimize dosing in Asian patients.