Effect of Lipid Profile Parameters on Noise Induced Hearing Loss.

Background: Noise induced hearing loss (NIHL) is an irreversible occupational disease among industrial workers. Recent studies have reported that changes in some metabolic factors such as the serum level of sugar and lipids might have a role in suffering from NIHL among workers exposed to noise. We designed this study to assess the association between lipid profile changes and NIHL occurrence among noise-exposed workers. Methods: This case-control study has been conducted according to noise-exposed workers registry data in one of the Iranian automobile factories between 2007 and 2017. We classified study workers into the NIHL and control groups. We assessed the impact of lipid profile parameters across the study groups using the independent samples t-test, chi-square, and regression. Results: The mean serum level of cholesterol was significantly higher in the NIHL group than in workers of the control group (215.27 ± 60.30 vs 204.49 ± 63.69 mg/dL; P = 0.041). Moreover, the serum level of HDL was significantly lower in workers in the NIHL group compared with the control group (35.21 ± 6.87 vs 37.43 ± 7.28 mg/dL; P < 0.001). Although other lipid profile parameters (LDL, TG, LDL/HDL ratio) were higher among workers of the NIHL group, their differences were not significant. Conclusion: A cholesterol level lower than 200 mg/dL is known as a protective factor and an HDL level lower than 40 mg/dL is an NIHL risk factor. More attention should be paid to controlling serum levels of cholesterol and HDL.

Assessment of Pulmonary Function Parameters, Signs, and Symptoms in the Employee of a Dairy Products Company in Tehran, Iran.

BACKGROUND: Workers in dairy products companies are exposed to different respiratory hazards. The current study aimed at investigating and comparing the prevalence of pulmonary function parameters, signs, and symptoms in the exposed workers and office staff. MATERIALS AND METHODS: The current cross sectional study was conducted in 2015 on 864 employees working in a dairy products company in Tehran, Iran. The subjects included 646 employees exposed to respiratory hazards at the production line and the other group consisted of 218 staff not exposed to respiratory hazards in the production line as the unexposed group. Demographic characteristics and the presence of respiratory symptoms and signs were gathered using a checklist. Spirometric indices including FEV1, forced volume vital capacity (FVC), and FEV1/FVC were measured for the study participants. RESULTS: Although exposure to the respiratory hazards among participants of the exposed group was lower than permitted limits, the frequency of respiratory signs and symptoms were significantly higher than those of the unexposed staff. In the current study, mean percentage of FVC, FEV1/FVC, and FEV1 were significantly less than the predicted amount in the exposed group than in the unexposed group. CONCLUSION: Although the frequency of respiratory signs and symptoms was lower than those of other similar studies, abnormal spirometric patterns were common; hence, it can be pointed out that even in the work environments, such as dairy products industry with below the permissible exposure limit of respiratory risks, multiple spirometric disorders can be observed. In other words, the absence of respiratory signs and symptoms are insufficient and application of different pulmonary function tests, such as spirometry, seem essential for assessment.

Assessment of Pulmonary Function Parameters and Respiratory Symptoms in Shipyard Workers of Asaluyeh City, Iran.

BACKGROUND: Workers in shipyard companies are exposed to different respiratory hazards. The present case-control study was designed to evaluate pulmonary function tests and respiratory symptoms among shipyard workers in Asaluyeh city in Southwest Iran. MATERIAL AND METHOD: Between March and October 2015 we recruited participants from two separate populations: shipyard workers as cases and office workers from the same shipyard company, who are not exposed to the same respiratory hazards, as controls. History was obtained from all participants and they all underwent physical examination and spirometry. RESULTS: Respiratory signs and symptoms were present in a significantly higher number of shipyard workers compared to the unexposed office workers. Similarly, there were significant spirometric differences between cases and controls. CONCLUSION: It seems that workplace hazards play a more significant role than other factors such as air pollution in development of respiratory diseases, and future studies for investigating respiratory symptoms, pulmonary function parameters, biological monitoring and measurement of respiratory hazard need to be performed.

Treatment of atrophic facial acne scars with fractional Er:YAG laser in skin phototype III-IV: A pilot study.

BACKGROUND: Fractional ablative lasers have recently been used for the treatment of skin scars. The objective of this study was to assess the efficacy and safety of the fractional erbium-doped yttrium aluminum garnet (Er:YAG) laser (2940 nm) in the treatment of skin scars. MATERIALS AND METHODS: A total of 9 patients (8 female, 1 male) with Fitzpatrick skin types III and IV suffering from atrophic facial acne scars were treated with a fractional Er:YAG laser for 2-5 (mean 3.3) sessions 4-6 weeks apart. One independent investigator assessed the efficacy, using standardized photographs, before and 1 month after the last treatment. The patients' satisfaction rate was also evaluated. RESULTS: The treatment was well tolerated by all patients without any anesthesia. The downtime was 2-3 days. All patients showed improvement in scars: excellent in 1, good in 1, and fair in 7 patients. Six patients were highly satisfied and 3 were satisfied with treatment. No adverse effect was noted. CONCLUSION: A fractional Er:YAG laser can deliver an effective and minimally invasive treatment for acne scars.

Evaluation of occupational allergic contact dermatitis and its related factors in Iran.

Background: Occupational contact dermatitis, especially in hand, is one of the most common occupational disorders. The present study aimed at evaluating patients with occupational allergic contact dermatitis (ACD) caused by common allergens based on occupation type and disease history. Methods: This cross-sectional study aimed at evaluating the data of the patients with probable diagnosis of ACD in Center for Research and Training in Skin Diseases and Leprosy (CRTSDL) in Iran. In the present study, 946 patients were assessed from different regions of Iran. One hundred fifty-one cases with positive patch test and relevant exposure were entered into the study; data related to their occupation and disease activity history were evaluated and recorded. Then, factors related to disease activity history were assessed considering the occupational groups and common exposures. Results: Nickel sulphate was the most common allergen in the 151 patients. Disease activity was constant in 29.8% of the patients; it increased in 27.8%, and decreased just before doing the patch test in 42.4%. Of the patients, 52.3% were getting worse during the working days. Occupational groups were significantly different in age and gender. Disease duration was also different in the occupational groups (p=0.001). The least disease duration was observed in healthcare workers, and the most in service workers. Lesions in the foot were related to period of employment. In administrative work group, (teachers, technicians and housewives) disease activity was decreased in the most cases, while it was increased in most patients of service workers (p=0.086). Conclusion: The present study, similar to previous reports, revealed that nickel sulphate is the most common allergen in ACD cases. Moreover, it was found that the symptoms of disease activity remained constant or increased in a significant proportion of the cases during the working days. Therefore, these workers should seriously follow up on this matter and change their occupation, or limit the exposure to allergens.

The effect of a multifaceted ergonomic intervention program on reducing musculoskeletal disorders in dentists.

Background: Work-related musculoskeletal disorders (WMSDs) are the most common occupational injuries in dentists. These disorders occur due to the specific characteristics of dentistry occupation such as the use of tools and instruments and awkward posture. The present study aimed at evaluating the effect of multifaceted ergonomic program on reducing musculoskeletal disorders in dentists. Methods: One hundred-two male dentists who worked in dentistry clinics of Tehran's hospitals participated in this interventional study. Participants were randomly divided into control (n=50) and intervention (n=52) groups. Dentists in the intervention group (n=52) underwent multifaceted ergonomic intervention program for 8 weeks and dentists in the control group (n=50) only received the measurements. The prevalence of musculoskeletal disorders was evaluated in each of the 2 groups at 3 time points before the intervention, 3, and 6 months after the intervention using the Nordic Musculoskeletal Questionnaire (NMQ). Paired t-test was used to compare the prevalence of musculoskeletal disorders before and after the ergonomic intervention program at the end of 3 and 6 months. Results: The results revealed that the prevalence of musculoskeletal disorders was reduced after the intervention in the neck, shoulder, arm, wrist, back, thigh, knees, and feet (p<0.05). On the other hand, the prevalence of musculoskeletal disorders increased in the control group in the neck, shoulder, arm, wrist, thigh, and knee, respectively. The survey results revealed that 98% of the participants agreed with this intervention program. Conclusion: The results of this study revealed that the multifaceted ergonomic intervention program, which included improving working conditions, identifying ergonomic risk factors, regular exercise, and discussion group meetings, could decrease the prevalence of musculoskeletal disorders in dentists.