Prevalence of secondhand smoke exposure in asthmatic children at home and in the car: A cross-sectional study

OBJECTIVE: To compare secondhand smoke exposure (SHSe) prevalence at home and inside the car between asthmatic and non-asthmatic Portuguese children. MATERIALS AND METHODS: This is a cross-sectional study that assessed children's SHSe in a representative sample of nine Portuguese cities. A validated self-reported questionnaire was administered to a random sample of 4th grade students during the school year of 2010/2011. The asthma prevalence was defined by the answers to three questions regarding asthma symptoms, medication and inhaler use. We performed chi-square tests and analysed frequencies, contingency tables, confidence intervals, and odd-ratios. RESULTS: The self-reported questionnaire was administered to 3187 students. Asthma prevalence was 14.8% (472 students). Results showed that 32.3% of non-asthmatic children and 32.4% of asthmatic children were exposed to secondhand smoke as at least one of their household members smoked at home. The prevalence of parental smoking, smoking among fathers and smoking among mothers at home was also similar in both groups (asthmatic and non-asthmatic children). SHSe inside the car was 18.6% among non-asthmatic children and 17.9% among asthmatic children. CONCLUSIONS: Asthmatic and non-asthmatic children were equally exposed to secondhand smoke, because no significant differences were found between the two groups concerning the prevalence of SHSe at home and inside the car. These findings highlight the need to include SHSe brief advice in paediatric asthma management.

The effects of ILFN-exposure on voice acoustic parameters of commercial cabin crewmembers

Background: Long-term exposure to infrasound and low frequency noise (ILFN <500 Hz, including infrasound) can lead to the development of vibroacoustic disease (VAD). VAD is a systemic pathology characterized by the abnormal growth of extracellular matrices in the absence of inflammatory processes, namely of collagen and elastin, both of which are abundant in the basement membrane zone of the vocal folds. ILFN-exposed workers include pilots, cabin crewmembers, restaurant workers, ship machinists and, in previous studies, even though they did not present vocal symptoms, ILFN-exposed workers had significant different voice acoustic patterns (perturbation and temporal measures) when compared with normative population. Study Aims: The present study investigates the effects of age and years of occupational ILFN-exposure on voice acoustic parameters of 37 cabin crewmembers: 12 males and 25 females. Specifically, the goals of this study are to: 1) Verify if acoustic parameters change over the age and years of ILFN-exposure and 2) Determine if there is any interaction between age and years of ILFNexposure on voice acoustic parameters of crewmembers. Materials and Methods: Spoken phonatory tasks were recorded with a C420III PP AKG head-worn microphone and a DA-P1 Tascam DAT. Acoustic analyses were performed using KayPENTAX Computer Speech Lab and Multi-Dimensional Voice Program. Acoustic parameters included speaking fundamental frequency, perturbation measures (jitter, shimmer and harmonicto- noise ratio), temporal measures (maximum phonation time and s/z ratio) and voice tremor frequency. Results: One-way ANOVA analysis revealed that as the number of ILFN-exposure years increased male cabin crewmembers presented significant different shimmer values of /i/ as well as tremor frequency of /u/. Females presented significantly different jitter % of /i, a, O/ (p <0.05). Lastly, Two-way ANOVA analysis revealed that for females, there was a significant interaction between age and occupational ILFN-exposure for voice acoustic parameters, namely for jitter’s mean for /a, O/ and shimmer’s (%) mean for /a, i/ (p <0.05). Discussion and Conclusion: These perturbation measure patterns may be indicative of histological changes within the vocal folds as a result of ILFN-exposure. The results of this study suggest that voice acoustic analysis may be an important tool for confirming ILFN-induced health effects.

Voice acoustic profi le of males exposed to occupational infrasound and low-frequency noise

Background: Vibroacoustic disease (VAD) is a systematic pathology characterized by the abnormal growth of extra-cellular matrices in the absence of infl ammatory processes, namely collagen and elastin, both of which are abundant in the basement membrane zone of the vocal folds. VAD can develop due to long-term exposure to infrasound and low-frequency noise (ILFN, <500 Hz). Mendes et al. (2006, 2008 and 2012) revealed that ILFN-exposed males and females presented an increased fundamental frequency (F0), decreased jitter %, and reduced maximum phonation frequency range, when compared with normative data. Temporal measures of maximum phonation time and S/Z ratio were generally reduced. Study Aims: Herein, the same voice acoustic parameters of 48 males, 36 airline pilots and 12 cabin crewmembers (age range 25-60 years) were studied, and the effects and interaction of age and years of ILFN exposure were investigated within those parameters. ILFN-exposure time (i.e. years of professional activity) ranged from 3.5 to 36 years. Materials and Methods: Spoken and sung phonatory tasks were recorded with a DA-P1 Tascam DAT and a C420III PP AKG head-worn microphone, positioned at 3 cm from the mouth. Acoustic analyses were performed using KayPENTAX Computer Speech Lab and Multi-Dimensional Voice Program. Results: Results revealed that even though pilots and cabin crewmembers were exposed to occupational environments with distinct (ILFN-rich) acoustical frequency distributions and sound pressure levels, differences in the vocal acoustic parameters were not evident. Analyzing data from both professional groups (N = 48) revealed that F0 increased signifi cantly with the number of years of professional activity. Conclusion: These results strongly suggest that the number of years of professional activity (i.e. total ILFN exposure time) had a signifi cant effect on F0. Furthermore, they may refl ect the histological changes specifi cally observed on the vocal folds of ILFN-exposed professionals.