it is a multisystem disorder affecting the gastrointestinal , respiratory , hepatobiliary , and reproductive systems , as well as the sweat glands ( 1 - 6 ) . cf is caused by a mutation in the cystictransmembrane conductance regulator ( cftr ) gene , leading to defective ion transport of the cftr protein ( 7 - 10 ) . although numerous mutations in the cftr gene have been reported as a primary cause in the clinical manifestations and outcome of cf ( 9 ) , recent research has focused on the role of other factors such as gender ( 11 , 12 ) , race ( 1 ) , age ( 11 ) , geographic area ( 2 ) , infection with pseudomonas aeruginosa ( 11 , 13 ) , religion ( 8) , culture ( 1 , 14 ) , and nutritional status ( 13 - 15 ) . recently , improvement and progress in outcomes have been observed through better understanding of the disease , finding the effective factors in the start and progression of the disease , and ultimately in better management of the disease ( 16 ) . these factors have led to earlier diagnosis and more timely treatment , which could affect the clinical course and change the outcome for a patient . therefore , the link among researchers and clinicians will be stronger due to extensive research on the disease and improved introduction of the disease ( 17 , 18 ) . in addition , the research results could have an effective role in changing of the culture and laws of a society . retrospective research , in spite of some disadvantages , plays an important role in depicting the disease ( 16 , 19 ) . this research has been conducted after searching the electronic databases and performing a literature review , to ensure that no similar study had been undertaken in the region . this study aimed to assess the association between outcomes and demographic status in azeri turkish patients with cystic fibrosis . this was a cross sectional study conducted at the educational and treatment children s hospital of the university of medical sciences and the medical genetic laboratory , tabriz , iran , from march 2001 to september 2014 . the educational and treatment children s hospital is a governmental , specialized , and referral hospital with 150 beds and six wards in northwestern iran and dr . m. rafeey is the top , and the most professional , physician in this field and region . this study was performed on azeri turks , who are members of one of the largest ethnic groups in iran ( 20 ) . all the medical records of the patients were reviewed using the census method , and further information was gathered from patients , or their parents , through telephone interviews . the diagnosis of cf was based on typical clinical features and confirmed by sweat chloride level > 60 meq / l , according to the method of gibson and cooke , or detection of mutations in the cftr gene known to cause cf ( 21 ) . the medical records of 442 patients who met the inclusion criteria were separately reviewed by two authors . patients with incomplete records and who were not diagnosed as having cf were excluded with the reviewer s agreement . the kappa agreement rate was higher than 85% , as inclusion criteria to the next phase . in the end , 331 cases were included in this study , which was conducted over a 13-year period from 2001 to 2014 . data included patient outcome , gender , age , residence , ranking in birth order of the family s children , family history , consanguineous marriage , degree of consanguineous marriage , and weight at birth . ranking in birth order of the family s children was divided into two groups , including one child as the first group , and two children or more as the second group . a positive family history for cf was considered as having had a first , second , or third - degree relative affected with cf ( 22 ) . a consanguineous marriage was defined as a union between two persons who are related as first cousins ( 3rd degree ) , first cousins once removed or double second cousins ( 4 degree ) , and second cousins ( 5 degree ) . the first degree and the second degree , first cousins were classified as the first group and the others as the second group . demographic data were analyzed using spss 18 for means and standard deviations for normally distributed continuous variables , and median and interquartile ranges were obtained for non - normally distributed continuous variables . the comparison between variables was analyzed with a chi - square or fisher s exact test , and independent samples t test . logistic regression analyses were carried out to identify variables independently associated with gender . in all analyses , odds ratio ( or ) with a 95% confidence interval , and p < 0.05 indicated statistical significance . ethical aspects were considered and approval for the study was gained by the ethics committee of the university ( no = 5/4/1775 ) . participants were assured of confidentiality , and consent was obtained from the patients or their parents . the diagnosis of cf was based on typical clinical features and confirmed by sweat chloride level > 60 meq / l , according to the method of gibson and cooke , or detection of mutations in the cftr gene known to cause cf ( 21 ) . the medical records of 442 patients who met the inclusion criteria were separately reviewed by two authors . patients with incomplete records and who were not diagnosed as having cf were excluded with the reviewer s agreement . the kappa agreement rate was higher than 85% , as inclusion criteria to the next phase . in the end , 331 cases were included in this study , which was conducted over a 13-year period from 2001 to 2014 . data included patient outcome , gender , age , residence , ranking in birth order of the family s children , family history , consanguineous marriage , degree of consanguineous marriage , and weight at birth . ranking in birth order of the family s children was divided into two groups , including one child as the first group , and two children or more as the second group . a positive family history for cf was considered as having had a first , second , or third - degree relative affected with cf ( 22 ) . a consanguineous marriage was defined as a union between two persons who are related as first cousins ( 3rd degree ) , first cousins once removed or double second cousins ( 4 degree ) , and second cousins ( 5 degree ) . the first degree and the second degree , first cousins were classified as the first group and the others as the second group . demographic data were analyzed using spss 18 for means and standard deviations for normally distributed continuous variables , and median and interquartile ranges were obtained for non - normally distributed continuous variables . the comparison between variables was analyzed with a chi - square or fisher s exact test , and independent samples t test . logistic regression analyses were carried out to identify variables independently associated with gender . in all analyses , odds ratio ( or ) with a 95% confidence interval , and p < 0.05 indicated statistical significance . ethical aspects were considered and approval for the study was gained by the ethics committee of the university ( no = 5/4/1775 ) . participants were assured of confidentiality , and consent was obtained from the patients or their parents . demographic data of this study is shown in table 1.there was a significant difference between frequencies of deceased and living patients ( p < 0.001 ) . in the application of the kolmogorov - smirnov test , age was assumed as non - normal distribution that uses the sample median and the iqr ( minimum - maximum ) , consequently , median age for living patients was 0.4 years ( 7 days30 years ) and median age at death was 4.8 years ( 3 months  43 years ) . abbreviations : d , days ; iqr , minimum - maximum ; m , months ; y , years . all data were mentioned as frequency ( % ) . for deceased cf - patients , median age at death and living cf - patients , median age at time of the study have been considered , because of non - normal of age and weight at birth , median and iqr were applied . eighty - five patients expired during the 13 years of the study with a mean of six deaths per year and at a ratio of 1:3 . during the time of the study , 77 ( 90.6% ) of the 85 deceased cf patients had died under the age of four years . among the 246 living cf patients , 131 ( 53.3% ) were less than four years of age . ( % ) . at first , we calculated the association between outcome and gender . at the time of the study , 51 ( 26.7% ) of the deceased patients were males and 34(24.3% ) were females . the  test did not show any significant difference between outcome and gender ( or = 1.13 [ 95% ci , 0.68 - 1.87 ] , p = 0.6 ) . in the next step , there was a significant difference between the outcome and the geographic location ( or = 0.55 [ 95% ci , 0.32 - 0.95 ] , p = 0.03 ) . there was no significant difference between outcome and ranking among the family s children , while 38 ( 23.9% ) were first - born children , and 47 ( 27.3% ) were second or later born children ( or = 0.83 [ 95% ci , 0.50 - 1.37 ] , p = 0.4 ) . in this study , we analyzed family history status among these patients , and the risk of mortality was approximately two times higher in patients with a positive family history than in those with a negative family history ( or = 1.91 [ 95% ci , 1.09 - 3.36 ] , p = 0.02 ) . there was a statistically significant difference between the outcome and consanguineous marriage ( or = 1.94 [ 95% ci , 1.14 - 3.29 ] , p = 0.01 ) , but no significant difference in degree of positive consanguineous marriage ( or = 0.68 [ 95% ci , 0.34 - 1.37 ] , p = 0.2 ) . the risk of mortality was 1.94 times higher for patients in consanguineous marriages than for those in non - consanguineous marriages . finally , weight at birth was computed and compared in cf patients , both deceased and living . there was no significant difference between the outcome and weight at birth ( or = 1 [ 95% ci , 1 - 1.001 ] , p = 0.7 ) ( tables 1 and 3 ) . there was no statistically significant difference when logistic regression analysis was considered with the or for all of the variables ( p > 0.05 ) . associations between gender , ranking in birth order of the family s children , degree of consanguineous marriage , and weight at birth were not significant in terms of outcome , and therefore , omitted from the final model . when residential area , family history , and consanguineous marriage were entered into the model , the difference associated with outcome and or was somewhat reduced . results of logistic regression analysis illustrated the adjusted or for the final model and are shown in table 3 . at first , we calculated the association between outcome and gender . at the time of the study , 51 ( 26.7% ) of the deceased patients were males and 34(24.3% ) were females . the  test did not show any significant difference between outcome and gender ( or = 1.13 [ 95% ci , 0.68 - 1.87 ] , p = 0.6 ) . in the next step , there was a significant difference between the outcome and the geographic location ( or = 0.55 [ 95% ci , 0.32 - 0.95 ] , p = 0.03 ) . there was no significant difference between outcome and ranking among the family s children , while 38 ( 23.9% ) were first - born children , and 47 ( 27.3% ) were second or later born children ( or = 0.83 [ 95% ci , 0.50 - 1.37 ] , p = 0.4 ) . in this study , we analyzed family history status among these patients , and the risk of mortality was approximately two times higher in patients with a positive family history than in those with a negative family history ( or = 1.91 [ 95% ci , 1.09 - 3.36 ] , p = 0.02 ) . there was a statistically significant difference between the outcome and consanguineous marriage ( or = 1.94 [ 95% ci , 1.14 - 3.29 ] , p = 0.01 ) , but no significant difference in degree of positive consanguineous marriage ( or = 0.68 [ 95% ci , 0.34 - 1.37 ] , p = 0.2 ) . the risk of mortality was 1.94 times higher for patients in consanguineous marriages than for those in non - consanguineous marriages . finally , weight at birth was computed and compared in cf patients , both deceased and living . there was no significant difference between the outcome and weight at birth ( or = 1 [ 95% ci , 1 - 1.001 ] , p = 0.7 ) ( tables 1 and 3 ) . there was no statistically significant difference when logistic regression analysis was considered with the or for all of the variables ( p > 0.05 ) . associations between gender , ranking in birth order of the family s children , degree of consanguineous marriage , and weight at birth were not significant in terms of outcome , and therefore , omitted from the final model . when residential area , family history , and consanguineous marriage were entered into the model , the difference associated with outcome and or was somewhat reduced . results of logistic regression analysis illustrated the adjusted or for the final model and are shown in table 3 . the association between non - genetic variables and mortality in individuals with cf has been established ( 2 , 6 ) . despite improved management and increased awareness , outcome remains an important issue for cf patients , because non - genetic parameters , especially demographic factors , have been ignored by researchers and clinicians . the current study was performed to highlight the associations between demographic parameters and outcomes in cf patients . in this study , the ratio of deceased patients to living patients was 1:3 , with a significant difference . eighty - five patients expired during the period of 13 years , with a mean of six deaths per year . in a study performed by dodge et al . in the uk from 1996 to 2003 , there were 1,066 deaths , with a mean of 133 deaths per year ( 15 ) . therefore , based on these findings the mortality rate is lower in our study than in the uk , perhaps because this study has been performed on an ethnic group in iran with a low incidence of cf . in addition , it is likely that a number of deaths were not recorded or were not reported by the family in our study . in a previous study in sweden , lannefors et al . reported data from 1971 - 1999 showing that while the incidence of cf was 1/5600 live - births , the mean and median age of living cf patients were 18  12 and 16 years , respectively . in this study , regarding deceased patients , 45% were older than 18 years and 10% were older than 35 years . in deceased patients , the median age at death was 26 years ( range 0 - 72 ) ( 2 ) . in another study , also , this statistic had been observed in median age at death . delayed diagnosis and inappropriate health care were risk factors for a younger median age at death in non - european countries ( 24 ) . in our study , living cf patients had lower mean , median , and were of an older age than that reported in developed countries . also , in deceased cf patients the mean and median age at death were lower than in developed countries . we hypothesize that this difference may be due to the lack of proper equipment , inadequate diagnostic processes , and absence of treatment by specialists and expert staff , as well as poor nutritional status in our region compared to developed countries ( 13 , 24 ) . in our study , there was no significant difference between outcome and gender ; however , the mortality rate was somewhat higher in males than females . a number of studies have indicated that males have a better survival rate than females , while lannefors et al . in another study , accumulated data related to the mortality rate between genders reflects a higher mortality rate in cf females compared to males ( 6 ) . cultural issues and intrinsic ethnic differences ( 1 ) , as well as religion ( 8 , 25 ) and geographical elements , ( 9 ) for example , females are more susceptible to cf because of their body functions ; consequently , they more often report problems than males . expression of problems can be observed more in females than males in our region because of cultural issues ( 26 ) . reasons for this difference may be unclear , so it is necessary to perform additional investigations in a large population from neighboring countries to elucidate this issue . in the current study , there was a significant difference between outcome and location of residence . the mortality rate of cf was 50% higher in rural patients than urban patients , in spite of less air pollution ( 10 ) , lower stress , sufficient exercise , and organic nutritional intake in rural areas ( 13 , 27 ) . the availability of appropriate facilities to diagnosis and treat the disease is an important factor in patient survival . growth and lung health of children is influenced by proper treatment , and decreased pulmonary function is associated with morbidity and shortened survival for cf patients ( 28 ) . continuous care , suitable food , and daily physiotherapy are the main elements in survival of cf ( 27 ) . the relationship between improved nutritional support and increased survival in cf has been established , and retention of balanced and stable nutritional status is the best method of treatment for cf ( 13 , 27 ) . preventive treatments , such as adequate exercise , have been introduced at early ages for cf patients , and it appears to be an important factor in health maintenance in patients with cf ( 27 ) . in addition , a healthy lifestyle ( 27 ) , related to appropriate family functioning ( 29 ) , elevated levels of social class , education , and higher income ( 19 , 30 ) are determinates of survival for cf patients . patients living in urban areas are usually more likely to benefit from these conditions . in this study , there was no significant difference between outcome and ranking in birth order of the family s children , although the mortality rate was slightly higher for the second or subsequent children than for the first - born . management of patients with cf is one of the greatest challenges for families , and the family plays an important role in the treatment of cf ( 30 ) . cf patients need constant care such as physiotherapy , various medications , proper dietary intake , exercise , and adequate support ( 21 , 31 ) . on the other hand , high socioeconomic status with adequate income , suitable occupation , and employment status were identified as factors related to a good prognosis in affected individuals ( 30 ) . in crowded families , patients with a positive family history , such as a diagnostic category ( 32 , 33 ) , had a higher mortality rate than those with a negative family history . there was a significant difference , with the risk of mortality approximately two times , or 91% , higher with a positive family history than a negative family history , in the current study . ormond et al . published findings of a study stating that individuals affected by cf are segregated into four categories based on severity of disease . patients with a family history of cf showed a broader range of superficial severity with an unknown reason ( 34).understanding the reasons these patients have poorer prognoses than others will need additional research . considering consanguineous marriage as a predicating factor of outcome , children born to related parents were 94% more at risk for death than children of non - consanguineous marriage , especially in consanguineous marriage of the first - cousin type ( 3rd - degree ) . social conditions , religion , economic situations , and traditional beliefs are essential considerations in the preference for consanguineous marriage . in muslim populations , first - cousin unions ( 3rd - degree ) between a man and his father s or mother s brother s daughter , and the opposite , were detected frequently . the incidence of consanguinity has been reported to be 56% in middle east with saudi arabia having the highest prevalence at 89% in families with cf ( 35 ) . most studies have shown that early mortality is higher in the progeny of consanguineous unions than in non - consanguineous marriage ( 36 ) . ultimately , weight at birth was reviewed in deceased patients and living patients and no significant difference between them was found . the mean of weight at birth in the living cf population was slightly higher than the deceased cf population . cf is an autosomal recessive disorder affecting several organs , such as the digestive system , which is manifested in fat malabsorption , steatorrhea , and poor growth ( 2 , 21 ) . patients who intake adequate dietary requirements and gain proper weight have better pulmonary function ( 1 , 13 ) . an increased rate of mortality was associated with malnutrition , growth retardation , and declining lung function ( 1 , 13 , 37 ) . it is thought that in consanguineous marriage this was observed and that low weight at birth in cf patients causes shortened survival . the presence of ranking among the family s children , degree of consanguineous marriage , and weight at birth do not rule in the mortality of cf , although location of residence , family history , and consanguineous marriage are predictors of increased mortality in cf patients . the primary weakness of this study was that it was a retrospective study and may have limited accuracy , but it does lead the way to prospective research . another weak point was the investigation was limited to a specialist group , which decreases the ability to generalize the study results . data were limited to the children s hospital of the university of medical sciences and medical genetic laboratory in tabriz , and it was possible that some cf patients were not referred to these centers . the strength of this study was the adequate sample size in this population , and that it was conducted over a long period of time . data that was approved by two reviewers were collected from educational , referral , and therapeutic centers , and were designed to evaluate the effects of non - genetic factors on outcomes . this study was conducted in a population with a unique religion , ethnic origin , and culture , which could be a basis for the performance of comparative studies . this study indicates an association between outcome and the number of demographic factors in cf patients and emphasized the role of these factors in outcomes . clinicians need to be aware and educate patients and their families about treatments such as the correct use of medicines ( oral nutritional supplements , antibiotics , and nebulizers ) , physiotherapy , and proper nutrition , which are essential for a positive prognosis , especially in patients living in rural areas . it should be required that the government and relevant organizations focus on informing the public of the dangers of consanguinity . couples with consanguineous marriages , especially with a positive family history of the disease , require more frequent and thorough evaluations before pregnancy . other studies were performed for evaluating the association , if any , between outcome and other demographic factors . in this study , the ratio of deceased patients to living patients was 1:3 , with a significant difference . eighty - five patients expired during the period of 13 years , with a mean of six deaths per year . in a study performed by dodge et al . in the uk from 1996 to 2003 , there were 1,066 deaths , with a mean of 133 deaths per year ( 15 ) . therefore , based on these findings the mortality rate is lower in our study than in the uk , perhaps because this study has been performed on an ethnic group in iran with a low incidence of cf . in addition , it is likely that a number of deaths were not recorded or were not reported by the family in our study . in a previous study in sweden , lannefors et al . reported data from 1971 - 1999 showing that while the incidence of cf was 1/5600 live - births , the mean and median age of living cf patients were 18  12 and 16 years , respectively . in this study , regarding deceased patients , 45% were older than 18 years and 10% were older than 35 years . in deceased patients , the median age at death was 26 years ( range 0 - 72 ) ( 2 ) . in another study , also , this statistic had been observed in median age at death . delayed diagnosis and inappropriate health care european countries ( 24 ) . in our study , living cf patients had lower mean , median , and were of an older age than that reported in developed countries . also , in deceased cf patients the mean and median age at death were lower than in developed countries . we hypothesize that this difference may be due to the lack of proper equipment , inadequate diagnostic processes , and absence of treatment by specialists and expert staff , as well as poor nutritional status in our region compared to developed countries ( 13 , 24 ) . in our study , there was no significant difference between outcome and gender ; however , the mortality rate was somewhat higher in males than females . a number of studies have indicated that males have a better survival rate than females , while lannefors et al . 15 ) showed 45% and 49% of males with cf expired , respectively . in another study , accumulated data related to the mortality rate between genders reflects a higher mortality rate in cf females compared to males ( 6 ) . cultural issues and intrinsic ethnic differences ( 1 ) , as well as religion ( 8 , 25 ) and geographical elements , ( 9 ) may be reasons for the differences . for example , females are more susceptible to cf because of their body functions ; consequently , they more often report problems than males . expression of problems can be observed more in females than males in our region because of cultural issues ( 26 ) . reasons for this difference may be unclear , so it is necessary to perform additional investigations in a large population from neighboring countries to elucidate this issue . in the current study the mortality rate of cf was 50% higher in rural patients than urban patients , in spite of less air pollution ( 10 ) , lower stress , sufficient exercise , and organic nutritional intake in rural areas ( 13 , 27 ) . the availability of appropriate facilities to diagnosis and treat the disease is an important factor in patient survival . growth and lung health of children is influenced by proper treatment , and decreased pulmonary function is associated with morbidity and shortened survival for cf patients ( 28 ) . continuous care , suitable food , and daily physiotherapy are the main elements in survival of cf ( 27 ) . the relationship between improved nutritional support and increased survival in cf has been established , and retention of balanced and stable nutritional status is the best method of treatment for cf ( 13 , 27 ) . preventive treatments , such as adequate exercise , have been introduced at early ages for cf patients , and it appears to be an important factor in health maintenance in patients with cf ( 27 ) . in addition , a healthy lifestyle ( 27 ) , related to appropriate family functioning ( 29 ) , elevated levels of social class , education , and higher income ( 19 , 30 ) are determinates of survival for cf patients . patients living in urban areas are usually more likely to benefit from these conditions . in this study , there was no significant difference between outcome and ranking in birth order of the family s children , although the mortality rate was slightly higher for the second or subsequent children than for the first - born . management of patients with cf is one of the greatest challenges for families , and the family plays an important role in the treatment of cf ( 30 ) . cf patients need constant care such as physiotherapy , various medications , proper dietary intake , exercise , and adequate support ( 21 , 31 ) . on the other hand , high socioeconomic status with adequate income , suitable occupation , and employment status were identified as factors related to a good prognosis in affected individuals ( 30 ) . in crowded families , patients with a positive family history , such as a diagnostic category ( 32 , 33 ) , had a higher mortality rate than those with a negative family history . there was a significant difference , with the risk of mortality approximately two times , or 91% , higher with a positive family history than a negative family history , in the current study . ormond et al . published findings of a study stating that individuals affected by cf are segregated into four categories based on severity of disease . patients with a family history of cf showed a broader range of superficial severity with an unknown reason ( 34).understanding the reasons these patients have poorer prognoses than others will need additional research . considering consanguineous marriage as a predicating factor of outcome , children born to related parents were 94% more at risk for death than children of non - consanguineous marriage , especially in consanguineous marriage of the first - cousin type ( 3rd - degree ) . social conditions , religion , economic situations , and traditional beliefs are essential considerations in the preference for consanguineous marriage . in muslim populations , first - cousin unions ( 3rd - degree ) between a man and his father s or mother s brother s daughter , and the opposite , were detected frequently . the incidence of consanguinity has been reported to be 56% in middle east with saudi arabia having the highest prevalence at 89% in families with cf ( 35 ) . most studies have shown that early mortality is higher in the progeny of consanguineous unions than in non - consanguineous marriage ( 36 ) . ultimately , weight at birth was reviewed in deceased patients and living patients and no significant difference between them was found . the mean of weight at birth in the living cf population was slightly higher than the deceased cf population . cf is an autosomal recessive disorder affecting several organs , such as the digestive system , which is manifested in fat malabsorption , steatorrhea , and poor growth ( 2 , 21 ) . patients who intake adequate dietary requirements and gain proper weight have better pulmonary function ( 1 , 13 ) . an increased rate of mortality was associated with malnutrition , growth retardation , and declining lung function ( 1 , 13 , 37 ) . it is thought that in consanguineous marriage this was observed and that low weight at birth in cf patients causes shortened survival . the presence of ranking among the family s children , degree of consanguineous marriage , and weight at birth do not rule in the mortality of cf , although location of residence , family history , and consanguineous marriage are predictors of increased mortality in cf patients . the primary weakness of this study was that it was a retrospective study and may have limited accuracy , but it does lead the way to prospective research . another weak point was the investigation was limited to a specialist group , which decreases the ability to generalize the study results . data were limited to the children s hospital of the university of medical sciences and medical genetic laboratory in tabriz , and it was possible that some cf patients were not referred to these centers . the strength of this study was the adequate sample size in this population , and that it was conducted over a long period of time . data that was approved by two reviewers were collected from educational , referral , and therapeutic centers , and were designed to evaluate the effects of non - genetic factors on outcomes . this study was conducted in a population with a unique religion , ethnic origin , and culture , which could be a basis for the performance of comparative studies . this study indicates an association between outcome and the number of demographic factors in cf patients and emphasized the role of these factors in outcomes . clinicians need to be aware and educate patients and their families about treatments such as the correct use of medicines ( oral nutritional supplements , antibiotics , and nebulizers ) , physiotherapy , and proper nutrition , which are essential for a positive prognosis , especially in patients living in rural areas . it should be required that the government and relevant organizations focus on informing the public of the dangers of consanguinity . couples with consanguineous marriages , especially with a positive family history of the disease , require more frequent and thorough evaluations before pregnancy . other studies were performed for evaluating the association , if any , between outcome and other demographic factors .
backgroundoutcomesforcystic fibrosis patients are improving rapidly . 
 the demographic factors are notable variables inoutcomes , which can be evaluated and modified.objectivesthis study was designed to investigate the association between outcome and demographic factors in patients with cystic fibrosis.patients and methodsthis was a cross - sectional study and data were gathered for 331 patients using the census method , from march 2001 to september 2014 in iran . 
 data was analyzed using logistic regression analysis , chi - square test , and independent sample t test using spss 18 . 
 odds ratio with confidence intervals of 95% and p < 0.05 were considered significant.resultsthere were 85 ( 25.7% ) deceased patients and 246 ( 74.3% ) living patients at the time of the study . 
 of the 246 living cf patients , 202 ( 82.2% ) were less than nine years of age , and 77 ( 90.6% ) out of the 85 deceased cf patients had died younger than four years of age . 
 there was a significant difference between outcome and location of residence . 
 the risk of mortality was 50% less in urban patients than in rural patients ( p = 0.03 ) . 
 the risk of mortality was approximately two times higher in patients with a positive family history than in those with a negative family history ( p = 0.02 ) . 
 the proportion of mortality was approximately two times , or 94% , higher for those in a consanguineous marriage than for those in a non - consanguineous marriage ( p = 0.01).conclusionsthe results demonstrated that the mortality rate was higher in cf patients with a positive family history , a consanguineous marriage , and residence in a rural area . 
 therefore , demographic factors play an important role in the outcome of cystic fibrosis . 
 unfortunately , these parameters , which can be managed easily and with low cost , have been overlooked .