Tolerance & Time margin

Abstract Background: The tear film breakup time (tBUT) is a clinical evaluation of evaporative dry eye disease assessed by instilling topical fluorescein into the eyes. In the present study, we introduce a new diagnostic test, blinking tolerance time (BTT), for self-evaluation of tear-film stability. We compared the results with the tBUT and validated the BTT test for self-assessment of tear film instability.Methods: This was a prospective controlled study involving 212 eyes of 106 participants 20–79 years of age. A total of 114 eyes of 57 dry eye patients and 98 eyes of 49 healthy subjects were included in the study. All patients and subjects were administered the following tests to diagnose dry eye disease: Ocular Surface Disease Index, BTT, tBUT, slit-lamp examination, corneal stain score, and Schirmer I test (without anesthesia). Patients and subjects were instructed not to blink for as long possible after reset blinking. The time interval between the reset blink and the next blink was measured. The mean of 3 tBUT values in both the right and left eyes was defined as tBUTBE. Correlations between the BTT and tBUTBE were also evaluated. To evaluate the diagnostic efficacy of the BTT and tBUT tests, receiver operating characteristic (ROC) curves were generated to obtain a cutoff score, and the sensitivities of the tests against the specificity at all possible thresholds were plotted.Results: Spearman’s correlation analysis revealed a significant weakly positive correlation between BTT and tBUTBE (r = 0.447; p=0.000). The intraclass correlation coefficient (ICC) of the tBUT was 0.679 (95% confidence interval [CI]: 0.575–0.765) and the ICC of the BTT was 0.904 (95% CI: 0.867–0.932). The area under the ROC curve did not significantly differ between the tBUTBE (0.678) and BTT (0.628, p=0.641). When the cutoff value of the BTT test was set to 8.1 s, the sensitivity was 63.3% and the specificity was 56.1%.Conclusion: The BTT test is a simple, inexpensive, and effective method for self-diagnosing dry eye that can also be used in the clinical setting.

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Objective pain sensitivity affects sleep quality in opioid dependent males on methadone maintenance therapy

10.7287/peerj.preprints.615 ◽

2014 ◽

Author(s):

Zalina Zahari ◽

Chee Siong Lee ◽

Soo Choon Tan ◽

Nasir Mohamad ◽

Yeong Yeh Lee ◽

...

Keyword(s):

Maintenance Therapy ◽

Sleep Quality ◽

Pain Sensitivity ◽

Methadone Maintenance ◽

Methadone Maintenance Therapy ◽

Pain Tolerance ◽

Opiate Withdrawal ◽

Tolerance Time ◽

Male Patients ◽

The Mean

Aim Pain associated poor sleep quality has been reported among opioid dependent patients on methadone maintenance therapy (MMT) but objective pain data are lacking. This study aimed to investigate the rate of objective pain sensitivity and the relationship between pain sensitivity and sleep quality in this susceptible male population. Methods A total of 168 male patients from MMT clinic in Kelantan, Malaysia were included into the study. Objective pain tolerance to cold pressor test (CPT) was evaluated at 0 hour and at 24 hours after the first CPT. Malay version of the Pittsburgh Sleep Quality Index – PSQI and the subjective opiate withdrawal scale (SOWS) questionnaires were administered to evaluate the quality of sleep and withdrawal symptoms, respectively. Results The mean age of the study participants was 37.22 (SD 6.20) years old. The mean daily methadone dose was 76.64 (SD 37.63) mg/day. The mean averaged SOWS score was 5.43 (SD 6.91). The averaged pain tolerance time ranged from 7 to 300 s with a mean time of 32.16 (SE 2.72) s, slightly below the cut-off score of 37.53 s. More specifically, 78.6% (n = 132) of patients were identified as ‘pain-sensitive’ (averaged pain tolerance time ≤ 37.53 s), and 36 (21.4%) were ‘pain-tolerant’ patients (averaged pain tolerance time > 37.53 s). The mean global PSQI score was 5.47 (SD 2.74). The pain-sensitive patients reported poorer sleep quality with mean (SD) of 5.78 (2.80) compared with pain-tolerant patients with mean (SD) of 4.31 (2.18) (p = 0.005). With analysis of covariance, pain-sensitive patients were found to have higher global PSQI scores (adjusted mean 5.76, 95% CI 5.29; 6.22) than pain-tolerant patients (adjusted mean 4.42, 95% CI 3.52; 5.32) (p = 0.010). Conclusions Many opioid dependent male patients on MMT are pain-sensitive. A poorer sleep quality is associated with objective pain sensitivity. Pain and sleep complaints in this susceptible population should not be overlooked.

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