1. Introduction
rontotemporal Dementia (FTD) is a lobar degeneration that account for 8-10% of all types of dementia cases. In FTD, asymmetric neuronal loss in frontal lobe and anterior temporal lobes can occur, and the posterior part of the brain is spared. FTD can cause severe brain atrophy [1]. The most common symptoms of FTD are memory loss, confusion, poor judgment, change in personality, and language disorder [2]. FTD has two main types; behavioral and primary progressive aphasia. The primary progressive aphasia has two subtypes of semantic and non-fluent aphasia [2]. In patients with behavioral symptoms, at the first course of FTD, the brain atrophy begins from the frontal lobe. Their symptoms are more behavioral such as loss of empathy, inappropriate attitude, sweet craving, and poor organization and judgment. They also have the frontal atrophy signs including primitive reflexes such as grasp reflex. In addition, they have impairment in frontal lobe tasks (Luria test), sequencing task, and word finding [4]. Primary progressive aphasia is diagnosed when a patient has isolated language deficit as the initiating symptom. The brain atrophy mainly occurs in perisylvian sulcus and anterior temporal lobe with dominance in the left side [4]. People with semantic dementia have problems with word comprehension and understanding the meaning of the words, and their speech lacks the meaning, while those with non-fluent aphasia have impaired speech fluency, agrammatism, speech apraxia and anomia, in addition to problems in repetition test.
The Persian Western Aphasia Battery (P-WAB-1) test used in this study consists of six linguistic subtests, each with a raw score of 10. According to the WAB-Revised manual, there is an Aphasia Quotient (AQ) score formulated based on the raw score in order to determine the overall severity of aphasia [8]. The P-WAB-1 has six sections: a: Spontaneous speech (10 points) containing three conversational questions (5 points) and spontaneous speech content (5 points); B: Spontaneous speech fluency (10 points); C: Auditory verbal comprehension including ten Yes/No questions (10 points); D: Sequential commands including five commands of different complexities (10 points); E: Repetition including six words and sentences with different length (10 points); and F: Naming, including 20 different naming categories (10 points). The P-WAB-1 subtests are chosen to represent equally important functions of the spoken language in order to obtain a numerical value of aphasia severity (AQ score) [8] which does not require statistical transformation by the clinician.
2. Methods
Participants were 20 FTD patients aged 58-78 years (13 men and 7 women) referred to dementia clinic of Rasul Akram Hospital in Tehran, Iran. First, their disease history was surveyed and physical examination was performed on them by a neurologist. Then, they underwent brain Magnetic Resonance Imaging (MRI) whose results led to the clinical diagnosis of FTD. The patients were then divided into three groups of behavioral variant, semantic dementia and non-fluent aphasia. After recording their characteristics in each group, P-WAB1 was performed on them. The goal was to compare the overall score (AQ) in different groups. Data were analyzed in SPSS to assess the validity of the test score for diagnosing the type of FTD.
3. Results
The AQ score was higher in patients with progressive non-fluent aphasia due to their better general cognitive state. The only domain that was affected in these patients was the speech fluency domain (Table 1). 


4. Discussion 
In our study we determined the characteristics of patients with FTD in Iranian samples for the first time. We also revealed that the P-WAB1 can help diagnose non-fluent aphasia in patients with no obvious clinical symptoms. Patients who suffer from non-fluent dementia seem to can get benefit from the rehabilitation programs. We studied only 20 patients with FTD, because the FTD, unlike Alzheimer’s disease, is not very common in dementia patients. Further studies are recommended using a larger ample size and also on patients with other types of dementia to compare their score with the score of FTD patients. 

Ethical Considerations
Compliance with ethical guidelines
This study was approved by the institutional review board at Iran University of Medical Sciences (Code: IR.IUMS.REC.1397.1396).

Funding
This study was funded by the Iran University of Medical Sciences. 

Authors contributions
designed the study: Mahsa zarei; designed the study and review of the manuscript: Reza Nilipour; statistical analyses: Mohsen Shati; performed the test: Shohreh Shakeri; reviewed the manuscript: Reza Arezoomandan; participated in data collection and data entry: Kimia Amirzadeh; Approve manuscript: All authors.

Conflicts of interest
The authors declare no conflict of interest.

Acknowledgements
The authors would like to thank the School of Behavioral Sciences and Mental Health - Iran University of Medical Sciences for their financial support, and Dr. Babak Zamani (Neurologist, the head of dementia clinic at Rasul Akram Hospital) for patient referral and scientific advice.


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