Evaluation and Comparison of the Indices of Systemic Oxidative Stress among Black-Africans with Age-related Cataracts or Primary Glaucoma.

PURPOSE: Oxidative stress has been implicated in the pathophysiology of glaucoma, cataract, and many degenerative diseases. The purpose of this study is to evaluate the systemic oxidative stress in black-African patients diagnosed with primary glaucoma or age-related cataract (ARC) and compare these indices to normal control patients and between the two conditions. METHODS: This was a descriptive cross-sectional study of consecutive recruited subjects attending a tertiary care facility. One hundred adults were enrolled and sub-grouped into: Normal controls (n = 20), patients with primary glaucoma (n = 40), and patients with cataract (n = 40). The data were collected on patient demographics and clinical information. Ten milliliters of the venous blood was taken from each subject for the evaluation of serum biochemical indices of oxidative stress. Laboratory measurements of enzymatic and nonenzymic anti-oxidants, as well as lipid peroxidation, were conducted using established and validated spectrophotometric methods. The systemic oxidative stress was measured by the serum levels of anti-oxidant enzymes and lipid peroxidation, and compared between the groups and to a control group of patients. RESULTS: Statistically, significantly reduced serum levels of glutathione, glutathione-S-transferase, superoxide dismutase, catalase, and ascorbic acid were found in the patients with glaucoma or cataract when compared with controls (P < 0.05 for all). Differences in serum lipid peroxidation levels across or between the groups were nonsignificant. Serum protein levels were significantly higher among the subjects with cataract or glaucoma than in controls. CONCLUSION: Our results concur with findings in Caucasian study cohorts. This indicates that in black-Africans, primary glaucoma, and ARC are associated with increased systemic oxidative stress. This supports the existing evidence on the role of oxidative stress in these ocular disorders and reinforces the rationale for the use of anti-oxidants in the management and possible prevention of these conditions.

Comparison of the average of five readings with averages from fewer readings for automated oscillometric blood pressure measurement in an outpatient clinic.

BACKGROUND AND OBJECTIVES: The optimal number of consecutive measurements for obtaining an average blood pressure (BP) reading in clinical practice is yet undefined by research. This study aimed to compare readings obtained from an average of 5 with averages of 2, 3, and 4, sequential measurements. SUBJECTS AND METHODS: Using an automated oscillometric device (BpTRU), BP measurement was conducted on 410 consenting adults attending a general outpatients clinic. Comparison of an average of 5 readings with averages of 2, 3, and 4 readings involved evaluation of correlations, Bland-Altman analysis, comparison of means and distribution of readings, and determination of the proportion of differences between compared readings which were clinically non-significant. RESULTS: 397 (96.8%) sets of complete BP readings were suitable for analysis. Clinically non-significant differences (≤5 mm Hg) were found between at least 79.3% (n=315) and 96.5% (n=383) of compared systolic and diastolic readings, respectively. Bland-Altman's analysis revealed that the 95% limits of agreement for the differences between compared readings were approximately 2-4, 3-7, and 4-11 mm Hg for 2, 3 and 4 readings' systolic comparisons while those for diastolic comparisons were 2-3, 3-5, and 4-7 mm Hg, respectively. Statistically non-significant differences were observed in all comparisons of the distributions of readings that were classified as <140 mm Hg or ≥140 mm Hg and <90 mm Hg or ≥90 mm Hg for systolic and diastolic readings, respectively. Strong positive correlations were found between 5 average readings and each of 2, 3, and 4 average readings, respectively. CONCLUSION: An average of 5 readings may be excessive for routine BP measurement using this device at outpatient clinics.

The effect of the first office blood pressure reading on hypertension-related clinical decisions.

The effect of the first office blood pressure reading (FBPR) on hypertension-related decisions was evaluated using blood pressure (BP) readings taken with the BpTRU BPM-100 device. BP readings were grouped into three pairs: (1) single readings (first and second readings), (2) computed average of three readings (one including and one excluding the first reading), and (3) computed average of five readings (one including and one excluding the first reading). Categorisation of BP readings under JNC-7 classes and distribution into < 140/90 and ≥ 140/90 mmHg groups were selected as parameters guiding hypertension-related decisions. Readings including FBPR had strong positive correlations to those excluding FBPR (Pearson's correlation coefficient ranged from 0.86-1.00). Also, FBPR-included and FBPR-excluded readings did not differ statistically in JNC-7 categorisation or distribution into < 140/90 or ≥ 140/90 mmHg groups. Our findings suggest that exclusion of FBPR may have no significant impact on hypertension-related clinical decisions.

Evaluation of the correlation between self-report and electronic monitoring of adherence to hypertension therapy.

Blood pressure (BP) control remains sub-optimal all over the world. Medication adherence is an important determinant of BP control. None of the available methods for measuring medication adherence is currently regarded as a universal consensus gold standard. In this study, we evaluated the correlation between self-report (Morisky's Medication Adherence Self-assessment Scale) and electronic (eCap) methods of medication adherence assessment. The self-report measure was administered at study entry while electronic compliance data was collected prospectively. Almost all (97.4%) of enrolled patients completed the study. Medication adherence scores ranged from 0 to 100% (69.33, ± 27.57) and 6.6-100% (66.92 ± 22.59) for Morisky's scale and eCap, respectively (Wilcoxon rank sum test, p = 0.253). Modal class interval for adherence scores were 61-80% (n = 28, 37.3%) and 81-100% (n = 23, 30.7%) for the eCap and Morisky's scale respectively. Overall, a weak correlation was found between the two methods (r = 0.056). The weak correlation was also maintained in subgroup analysis defined by attainment of BP control (r = 0.109 vs 0.0009), age (range r = -0.53 to 0.067), sex (0.009 to 0.151), level of education (-0.217 to 0.276), and Mini Mental State Examination score (-0.107 to 0.258). Our findings suggest that these methods are not equivalent in the evaluation of medication adherence.