Oral behaviours and wake-time masseter activity in patients with masticatory muscle pain

BACKGROUND

Little is known about wake-time masseter activity of patients with masticatory muscle pain in real-life settings.

OBJECTIVES

The aims of this study were (1) to assess wake-time masseter activity of women with masticatory muscle pain (MMP) and compare it with that of pain-free women; and (2) to investigate the association between objectively measured masseter contractions and self-reported oral behaviours.

METHODS

Adult women (N = 27) diagnosed with MMP were age-matched with pain-free women (N = 26). The electromyographic (EMG) activity of the masseter muscle when awake was recorded unilaterally for two consecutive days. The number of contraction episodes and relative contraction time (%) were calculated using cut-off thresholds of 3%, 5% and 10% of maximum voluntary contraction (MVC). Self-reported daytime oral activity was assessed using the Oral Behaviours Checklist (OBC, items 3-21). Data were analysed using univariate tests and mixed-model analyses.

RESULTS

The number of contraction episodes was similar between groups for all detection thresholds, but the relative contraction time at the lower detection thresholds (i.e. 3% MVC and 5% MVC) was significantly longer (1.5-fold) in the MMP than in the pain-free group. The OBC scores were significantly higher in the women with MMP than in controls, but no positive association could be found between EMG variables and OBC scores.

CONCLUSION

Women with MMP engage in low-level masseter muscle contractions, which last longer than those of pain-free controls. There was no relationship between self-reported oral behaviours and masseter activity when awake. These findings support the notion that prolonged low-level clenching when awake may play a role in the pathophysiology of MMP.

Fecal metagenomic profiles in subgroups of patients with myalgic encephalomyelitis/chronic fatigue syndrome

BACKGROUND

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is characterized by unexplained persistent fatigue, commonly accompanied by cognitive dysfunction, sleeping disturbances, orthostatic intolerance, fever, lymphadenopathy, and irritable bowel syndrome (IBS). The extent to which the gastrointestinal microbiome and peripheral inflammation are associated with ME/CFS remains unclear. We pursued rigorous clinical characterization, fecal bacterial metagenomics, and plasma immune molecule analyses in 50 ME/CFS patients and 50 healthy controls frequency-matched for age, sex, race/ethnicity, geographic site, and season of sampling.

RESULTS

Topological analysis revealed associations between IBS co-morbidity, body mass index, fecal bacterial composition, and bacterial metabolic pathways but not plasma immune molecules. IBS co-morbidity was the strongest driving factor in the separation of topological networks based on bacterial profiles and metabolic pathways. Predictive selection models based on bacterial profiles supported findings from topological analyses indicating that ME/CFS subgroups, defined by IBS status, could be distinguished from control subjects with high predictive accuracy. Bacterial taxa predictive of ME/CFS patients with IBS were distinct from taxa associated with ME/CFS patients without IBS. Increased abundance of unclassified Alistipes and decreased Faecalibacterium emerged as the top biomarkers of ME/CFS with IBS; while increased unclassified Bacteroides abundance and decreased Bacteroides vulgatus were the top biomarkers of ME/CFS without IBS. Despite findings of differences in bacterial taxa and metabolic pathways defining ME/CFS subgroups, decreased metabolic pathways associated with unsaturated fatty acid biosynthesis and increased atrazine degradation pathways were independent of IBS co-morbidity. Increased vitamin B6 biosynthesis/salvage and pyrimidine ribonucleoside degradation were the top metabolic pathways in ME/CFS without IBS as well as in the total ME/CFS cohort. In ME/CFS subgroups, symptom severity measures including pain, fatigue, and reduced motivation were correlated with the abundance of distinct bacterial taxa and metabolic pathways.

CONCLUSIONS

Independent of IBS, ME/CFS is associated with dysbiosis and distinct bacterial metabolic disturbances that may influence disease severity. However, our findings indicate that dysbiotic features that are uniquely ME/CFS-associated may be masked by disturbances arising from the high prevalence of IBS co-morbidity in ME/CFS. These insights may enable more accurate diagnosis and lead to insights that inform the development of specific therapeutic strategies in ME/CFS subgroups.

Comparative effectiveness of treatment options in elderly patients with colon cancer receiving adjuvant chemotherapy

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Background: While colon cancer (CC) is predominantly a disease of the elderly, older patients are underrepresented in clinical trials. We sought to evaluate whether the treatment patterns and benefits realized by trial participants pertain to older patients in the real-world setting.

Methods: Using the linked Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we conducted a retrospective cohort analysis of 3390 stage II and III CC patients diagnosed between 1/1/ 2004 to 12/31/2007, who were >66 years, enrolled in Medicare Parts A and B, and received adjuvant treatment with 5FU/LV (n=1368), FOLFOX (n=1398), CAP (capecitabine; n=507), and CAPOX (CAP + oxaliplatin; n=117) within 3 months after surgery. Date of last follow-up was 12/31/2007. Chi-square test and ANOVA or t-test assessed differences in patient and disease characteristics by treatment. Propensity score weighted Cox regression assessed the relative risk of death by treatment.

Results: Patients treated with CAP were older (mean age 77 years; p<.0001), more likely female (61%; p<.05), more likely non-white (19%; p<.05) and had higher co-morbidity score (p<.0001) compared to the other treatment groups. The mean time to chemo initiation after surgery were similar between the groups (mean 46-49 days) while mean duration of treatment were longer for 5FU/LV (149 days) and FOLFOX (144 days), compared to CAP (121 days) and CAPOX (111 days); p<.0001. The incidence of adverse events (AEs) within 180 days after initiation of treatment were higher in patients treated with FOLFOX (82%) and 5FU/LV (78%) compared to CAP (74%) and CAPOX (71%); p=0.0002. Propensity score adjusted multivariate analysis demonstrated comparable survival for CAP-based regimens vs. 5-FU/LV- based regimens ( table ).

Conclusions: Treatment outcomes for elderly patients observed in routine clinical practice were comparable between CAP-based and 5FU/LV-based regimens and consistent with results reported in randomized clinical trials. AEs associated with medical resource utilization were less frequent with CAP-based regimens.

[Table: see text]

Comparative effectiveness of chemotherapy in elderly patients with metastatic colorectal cancer

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Background: The management of metastatic colorectal cancer (mCRC) has evolved considerably with advances in chemotherapeutic agents that have led to improved outcomes. Less is known about the benefits of newer agents in the real-world setting. The objective of this study was to evaluate treatment patterns and survival in older, demographically diverse mCRC patients.

Methods: Using the linked Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we conducted a retrospective cohort analysis of 5931 stage IIIB, IIIC and IV CRC patients diagnosed between 1/1/ 2000 – 12/31/2007, who were >66 years, enrolled in Medicare Parts A and B, and received first-line treatment with 5FU/LV (n=2907), CAP (capecitabine; n=963), FOLFOX (n=1856) or CAPOX (CAP + oxaliplatin; n=205). Date of last follow-up was 12/31/2009. Statistical comparisons were made between 5FU/LV vs. CAP and FOLFOX vs. CAPOX. Cox regression with backward elimination estimated the relative risk of death, adjusting for demographic and clinical factors.

Results: Compared to 5FU/LV, patients treated with CAP were older (>80 years) at diagnosis (36% vs. 22%; p<.0001) and more likely female (59% vs. 53%; p=.0025), while patients receiving CAPOX were older (>80 years: 12% vs 8%; p<0.05) compared to FOLFOX. The mean time to chemotherapy initiation after diagnosis was similar between CAP and 5FU/LV (76 vs. 71 days) and between FOLFOX and CAPOX (75 vs. 70 days). The mean duration of treatment was longer for 5FU/LV (144 days) vs. CAP (122 days; p<.0001) and comparable between CAPOX (144 days) and FOLFOX (150 days; p=0.2139). The incidence of adverse events (AE) within 180 days after initiation of treatment were higher in patients treated with 5FU/LV (37%) vs. CAP (9%); p<.0001 and in FOLFOX (58%) vs. CAPOX (44%); p<0.0001. In multivariate analysis there were no significant differences in risk of death between CAP and 5FU/LV, and between CAPOX and FOLFOX ( table ).

Conclusions: Overall survival was comparable between CAP and 5FU/LV and between CAPOX and FOLFOX with fewer AEs associated with CAP and CAPOX. This provides real-world confirmation of clinical trial data.

[Table: see text]