Lifestyle including smoking, noise exposure with MP3 player and drinking alcohol are considered as risk factors for affecting hearing synergistically. However, little is known about the association of cigarette smoking with hearing impairment among subjects who carry a lifestyle without using MP3 player and drinking alcohol. We showed here the influence of smoking on hearing among Bangladeshi subjects who maintain a lifestyle devoid of using MP3 player and drinking alcohol. A total of 184 subjects (smokers: 90; non-smokers: 94) were included considering their duration and frequency of smoking for conducting this study. The mean hearing thresholds of non-smoker subjects at 1, 4, 8 and 12 kHz frequencies were 5.63±2.10, 8.56±5.75, 21.06±11.06, 40.79±20.36 decibel (dB), respectively and that of the smokers were 7±3.8, 13.27±8.4, 30.66±12.50 and 56.88±21.58 dB, respectively. The hearing thresholds of the smokers at 4, 8 and 12 kHz frequencies were significantly (p<0.05) higher than those of the non-smokers, while no significant differences were observed at 1 kHz frequency. We also observed no significant difference in auditory thresholds among smoker subgroups based on smoking frequency. In contrast, subjects smoked for longer duration (>5 years) showed higher level of auditory threshold (62.16±19.87 dB) at 12 kHz frequency compared with that (41.52±19.21 dB) of the subjects smoked for 1-5 years and the difference in auditory thresholds was statistically significant (p<0.0002). In this study, the Brinkman Index (BI) of smokers was from 6 to 440 and the adjusted odds ratio showed a positive correlation between hearing loss and smoking when adjusted for age and body mass index (BMI). In addition, age, but not BMI, also played positive role on hearing impairment at all frequencies. Thus, these findings suggested that cigarette smoking affects hearing level at all the frequencies tested but most significantly at extra higher frequencies.

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The association between chronic obstructive pulmonary disease (COPD) and occupational exposures are less studied in Bangladeshi context, despite the fact that occupational exposures are serious public health concerns in Bangladesh. Therefore, this study aimed to evaluate this association considering demographic, health and smoking characteristics of Bangladeshi population. This was a hospital-based quantitative study including 373 participants who were assessed for COPD through spirometry testing. Assessment of occupational exposures was based on both self-reporting by respondents and ALOHA based job exposure matrix (JEM). Here, among the self-reported exposed group (n = 189), 104 participants (55%) were found with COPD compared to 23 participants (12.5%) in unexposed group (n = 184) that differed significantly (p = 0.00). Similarly, among the JEM measured low (n = 103) and high exposed group (n = 236), 23.3% and 41.5% of the participants were found with COPD respectively; compared to unexposed group (14.7%; n = 34), that differed significantly also (p = 0.00). Likewise, participants with longer self-reported occupational exposures (>8 years) showed significantly (p = 0.00) higher proportions of COPD (79.5%) compared to 40.4% in shorter exposure group (1-8 years). Similarly, significant (p = 0.00) higher cases of COPD were observed among the longer cumulative exposure years (>9 years) group than the shorter cumulative exposure years (1-9 years) group in JEM. While combining smoking and occupational exposure, the chance of developing COPD among the current, former and nonsmokers of exposed group were 7.4, 7.2 and 12.7 times higher respectively than unexposed group. Furthermore, logistic analysis revealed that after adjustments for confounding risk factors, the chance of developing COPD among the self-reported exposure group was 6.3 times higher (ORs: 6.3, p = 0.00) than unexposed group; and JEM exposure group has odds of 2.8 and 1.1 respectively (p<0.05) for high and low exposures. Further studies are needed to reinforce this association between COPD and occupational exposure in Bangladesh.

ABSTRACT:Groundwater contamination by arsenic has created a major health hazard in Bangladesh by affecting millions of people. In this study, we report cytotoxic effects of arsenic in primary culture of murine thymocytes and the counteractive actions of tea extract to reduce this cytotoxic effects. When murine thymocytes were incubated for shorter period (1 h) with higher concentrations (50 and 100 µM) of sodium arsenite (NaAsO 2 ), cell viability was decreased to 79.06 ± 0.52% and 62.53 ± 0.23%, respectively. In case of longer incubation (16 hrs) with a wide range of NaAsO 2 concentration (1-100 µM), cell viability was reduced from 89.30 ± 0.84% to 79.0 ± 0.52% by 1 µM NaAsO 2 , and this reduction was continued with increasing concentration reaching to 29.60 ± 0.72% by 100 µM. Tea is known to possess antioxidant property and we found that this tea extract reduced NaAsO 2 -mediated death of the cells in culture. After 16 h of incubation, the chromosomal DNA of 5 µM NaAsO 2 -exposed cells was found degraded suggesting apoptotic death of the cells. Interestingly, this degradation of chromosomal DNA was blocked by tea extract. All of these results together suggest a future therapeutic application of tea extract to reduce or block arsenic toxicity.

Introduction: Early identification of chronic kidney disease (CKD) provides valuable opportunities for effective interventions that reduce the risk of outcomes, particularly renal failure. Objectives: This study aimed to screen the Bangladeshi asymptomatic adult population for CKD to identify potential risk factors for its development. Patients and Methods: The screening program was carried out among the 400 subjects in the Thakurgaon district of Bangladesh to identify people with the risk of CKD. All the subjects were asymptomatic and previously been never diagnosed with kidney diseases. Demographic data were collected by a structured questionnaire. Urinary protein was tested by dipstick method, and serum creatinine was measured by an auto-analyzer. Estimated glomerular filtration rate (eGFR) was calculated by using standard formula. CKD was diagnosed and classified according to the National Kidney Foundation (NKF) Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines. Results: A total of 18.2% respondents were found to have likely CKD to whom 82% were in stage 1 and 18% were in stage 2. The majority of the likely CKD respondents (30.1%) were in age >60 years. The prevalence of proteinuria was significantly (P=0.0001) higher among previously documented CKD patients compared to the control group. Logistic analysis revealed that after adjustments, CKD showed a significant association with diabetes mellitus (ORs: 7.46, P=0.00), smoking (ORs: 2.36, P=0.02), obesity (ORs: 3.98, P=0.00) and hypertension (ORs: 1.16, P=0.66) compared to control. Conclusion: A substantial number of adults were found to be unaware of the existence of CKD hence, large-scale prevention programs should be undertaken to reduce the classical risk factors of these disorders.

This study was performed to assess whether there is an association between elevated Fasting Blood Glucose (FBG) and hearing impairment in Bangladeshi population. A total of 142 subjects (72 with elevated FBG; 70 control) were included in the study. The mean auditory thresholds of the control subjects at 1, 4, 8 and 12 kHz frequencies were 6.35 ± 0.35, 10.07 ± 0.91, 27.57 ± 1.82, 51.28 ± 3.01 dB SPL (decibel sound pressure level), respectively and that of the subjects with elevated FBG were 8.33 ± 0.66, 14.37 ± 1.14, 38.96 ± 2.23, and 71.11 ± 2.96 dB, respectively. The auditory thresholds of the subjects with elevated FBG were significantly (p < 0.05) higher than the control subjects at all the above frequencies, although hearing impairment was most evidently observed at an extra-high (12 kHz) frequency. Subjects with a long duration of diabetes (>10 years) showed significantly (p < 0.05) higher level of auditory thresholds at 8 and 12 kHz, but not at 1 and 4 kHz frequencies, compared to subjects with shorter duration of diabetes (≤10 years). In addition, based on the data of odds ratio, more acute impairment of hearing at the extra-high frequency was observed in diabetic subjects of both older (>40 years) and younger (≤40 years) age groups compared to the respective controls. The binary logistic regression analysis showed a 5.79-fold increase in the odds of extra-high frequency hearing impairment in diabetic subjects after adjustment for age, gender and BMI. This study provides conclusive evidence that auditory threshold at an extra-high frequency could be a sensitive marker for hearing impairment in diabetic subjects.

This study was aimed at evaluating the association between gestational diabetes mellitus (GDM) and fetal birth weight considering duration of pregnancy, maternal age and body mass index (BMI). This was a retrospective cross-sectional study followed by cohort type of study. Initially, pregnant women in their 24 to 28th week of gestation were selected for determining their fasting blood glucose (FBG) level and blood glucose level 2 hrs after 75 g oral glucose intake. The cut-off value for the diagnosis of GDM was > 5.3 mmol/l for FBG level and > 8.6 mmol/l for taking 75 g oral glucose intake after 2 hrs. Both GDM and control group subjects were followed up to neonatal period to find out neonatal outcomes. Among the total 215 subjects, 84 pregnant women were selected with GDM and rest 131 were control. It is found that GDM alone had a significant (p = 0.05) positive effect on both the duration of pregnancy and fetal birth weight, but not on maternal BMI. Both the effects of duration of pregnancy and GDM are considered together on fetal birth weight, only GDM had significant impact on fetal birth weight compared to the control group. Similarly, when the effect of maternal BMI and GDM is considered together on fetal birth weight, only GDM group was found to have significant effect on fetal birth weight. Parallel results were observed for the effect of both maternal age and GDM on fetal birth weight. In binary logistic regression analysis, when the differences are considered in maternal age, duration of pregnancy and maternal BMI along with GDM, both maternal age ≥ 35 years (OR: 9.43, p = 0.001) and GDM (OR: 10.60, p = 0.003) was found to have significant positive effect on fetal birth weight. It was found that the GDM showed significant influence on fetal birth weight considering the effects of maternal age, duration of pregnancy and maternal BMI. Dhaka Univ. J. Biol. Sci. 29(2): 209-218, 2020 (July)