Medical Journal of The Islamic Republic of Iran (MJIRI)

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  Background :Aging can cause loss of balance, which may lead to physical and psychological problems. As the role of the otolith organs in maintaining postural stability has been emphasized in recent years, the present study investigated the effect of aging on saccular function using cervical vestibular evoked myogenic potentials (cVEMP).

  Methods : The participants were assigned into two groups group one included 31 young adults with a mean age of 22.15 (range: 19-26 yr) and group two consisted of 31 old adults with a mean age of 69.76 years (range: 61-79 yr). All participants hearing sensitivity was normal with no history of balance problems. VEMP was recorded for all subjects using tone burst 500 Hz stimuli at the threshold level and 95 dB nHL intensity level through air-conduction stimulation via an insert receiver.

  Results : There was a significant difference in the cVEMP response threshold (p<0.001), P1 wave latency (p<0.001), P1/N1 amplitude (p<0.001), and asymmetry ratio of P1/N1 amplitude (p<0.05) between the two groups. No significant difference was found between the left and right ears or in N1 wave latency between the two groups.

  Conclusion : VEMP abnormalities observed in healthy older adults showed the sensitivity of this test in identifying early signs of vestibular dysfunction. VEMP is an easy-to-use test that requires a short time to be performed. Therefore, it can be used as a selective objective screening test to detect vestibular disorders.

  

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Background: Stroke is a prevalent cause of disability in adults. The fall is the most common balance and motor impairments, which affects the quality of life in stroke patients. This study aims to employ random effects hurdle model for evaluating the balance improvement in stroke patients under the occupational therapy. Methods: In this longitudinal study with repeated measurement during one year between 2013 and 2014, the data was collected using non-random sampling method from three occupational therapy clinics. For a total of 38 stroke patients, the number of falls was recorded every two weeks. The random effects hurdle model and random effects zero inflated Poisson (ZIP) model were fitted to the data and were compared together. Data analysis was carried out using SAS Software version 9.2. Results: The results of random effects ZIP model showed that the covariates of sex and age and affected side of stroke and follow up duration had statistically significant effect on balance improvement (p< 0.05). The occupational therapy has been effective on balance improvement more than 40% during one year. Conclusion: The ZIP model with random effects can capture zero inflation and correlation structure in longitudinal count data simultaneously. Older patients, women and patients with left-side impairments were more at risk of fall and balance impairment, so they need more care and therapy.

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    Background: Use of methamphetamine (MA) and other stimulants has increased steadily over the past 10 years. Risk factor evaluation to reduce the problem in the community is one solution to protect people from addiction. This study aimed at using Bayesian zero- inflated Poisson (ZIP) model to investigate the relationship between the number of using crystal meth and some demographic factors in Tehran population.
   Methods: A cross-sectional study was conducted to investigate crystal meth abuse in Tehran, the capital of Iran, in 2012. Stratified sampling method was used to select samples from 22 urban areas of Tehran. Trained researchers referred to the public places, such as streets, parks, squares, and libraries, to perform face-to-face interviews with the randomly selected samples. Bayesian ZIP model was used to perform the analysis, and SAS 9.3 program was used for data analysis.
   Results: A total of 993 individuals were studied. According to Bayesian ZIP model, sex (mean= -0.27, 95%CI (-0.485, -0.061)), age (mean= 0.03, 95%CI (0.018, 0.043)), high school level education (mean= 1.276, 95%CI (0.699, 01.9)), diploma level education (mean= 10.4, 95%CI (0.511, 1.69)), and university level education (mean= 0.69, 95%CI (0.142, 1.33)) were all found to have significant associations with crystal meth usage, being the dependent variable.
   Conclusion: Males, those with higher education levels, and older people in Tehran population are more likely to use crystal meth. This demographic information may be useful in designing preventive programs. Moreover, it is better to analyze count data with excessive zeroes using Bayesian zero- inflated model instead of the usual count models.
 
 

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Dyspnea, shortness of breath, and inability to perform activities of daily living are the main complaints in patients with COVID-19 and physiotherapy has a vital role in managing such symptoms. We present a case treated with pulmonary and neurological physiotherapy, which improved symptoms and quality of life. In this case report, the importance and potential effect of concise physiotherapy on patients with COVID-19 is presented.

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