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chronic obstructive pulmonary disease ( copd ) is a major public health problem . across the world , as of 2010 , copd affected 329 million people or nearly 5% of the world 's population . in 2012 , it ranked as the third leading cause of death , killing over 3 million people .
copd is a noncurable disease , which progressively reduces breathing capacity and impairs patients ability to carry out activities of daily living , thereby adversely affecting health - related quality of life ( hrqol ) .
quality of life ( qol ) is an important aspect for measuring the impact of chronic diseases .
hrqol measurement facilitates the evaluation of efficacy of medical interventions and also the detection of groups at risk of psychological or behavioral problems .
many studies have been conducted across the world to study the hrqol of copd patients and the factors affecting it using both generic and disease - specific questionnaires .
however , studies from india and other developing nations are far fewer in number . more importantly ,
. this may be acceptable in developed nations where awareness and health care - seeking behavior is good but becomes important in developing countries such as india where people have poor health care - seeking behavior . in copd where the initial stages show none or few symptoms
, patients may not approach hospitals in the early stages and they may be missed in hospital settings leading to an overall result which shows worse qol . in recent times , care for patients with copd has increasingly moved from hospitals to primary care .
copd is a disease , which is mostly treated in home - based settings ; so , it is better to assess the hrqol of patients in a similar setting . since hrqol is an individual 's own perception , it may be affected in a hospital - based setting . also , patients may approach the health care provider because of exacerbation , which may further affect the results as qol worsens during exacerbation . taking these points into consideration , we decided to assess the hrqol of copd patients at their homes .
this was made possible as this study was part of a larger study conducted by the same authors where we determined the prevalence of copd in a spirometry - based cross - sectional study .
the study conducted had the following objectives : 1 ) to assess the qol of copd patients using st .
george 's respiratory questionnaire for copd patients ( sgrq - c ) questionnaire 2 ) to determine the factors associated with the qol of copd patients . in order to understand the complexity of living with copd ,
it is important that we understand which factors , in addition to physical functioning and complaints , are associated with hrqol .
this study was part of a larger community - based cross - sectional studyin which 1,220 subjects ( aged 40 years ) were studied to determine the prevalence of copd in the rural and urban areas of aligarh , uttar pradesh , india .
the urban and rural field areas under the department of community medicine of jawaharlal nehru medical college were chosen as study areas .
subjects were informed about the nature and consequences of the study and their consent was taken .
all those above 40 years of age and who gave consent were included in the study . all those who refused spirometry or were not fit for it ( those with recent myocardial infarction , stroke , eye surgery , thoracic / abdominal surgery , hemoptysis , known thoracic , aortic , or cerebral aneurysm , or uncontrolled hypertension ) were excluded from the study .
spirometry was conducted using a portable medical international research ( mir ) spirolab ii spirometer ( mir co. , italy ) .
of the 1,220 subjects studied , 124 were diagnosed with copd ( a prevalence of 10.2% ) .
all the subjects diagnosed with copd were assessed for their hrqol using the sgrq - c questionnaire .
sgrq is a standardized , self - administered questionnaire for measuring impaired health and perceived hrqol in airways disease .
the sgrq - c is a shorter version derived from the original version [ st . george 's respiratory questionnaire ( sgrq ) ] following a detailed analysis of data from large studies in copd .
it contains 40 items compared with the original 50 , with 76 weighted responses that cover three domains : symptoms , activity , and impact .
the sgrq - c is scaled from 0 to 100 ; with 0 representing the best hrqol .
this instrument has been demonstrated to be valid , reliable , and responsive among patients with copd .
the chronic lung disease ( cld ) severity index was used to quantify respiratory symptoms .
this is a short six - item questionnaire , which evaluates dyspnea , wheezing , and productive cough .
raw scores were added and transformed to a scale from 0 ( normal ) to 100 ( most severe ) .
the medical research council ( mrc ) five - point scale for breathlessness was used to assess dyspnea .
patients were inquired about their duration of illness , smoking status , and duration of smoking .
sociodemographic information was also collected from every patient , which included age , sex , education , socioeconomic status , occupation , and area of residence ( rural or urban ) .
sli was used in the national family health survey ( nfhs)-2 and was created by assigning scores to a range of 30 household goods and assets , including the type of housing and toilet facilities , fuel used for cooking , and ownership of durable goods . data entry and statistical analysis were performed using the statistical package for the social sciences ( spss ) software , version 17.0 ( spss , chicago , il , usa ) .
relationship between hrqol scores and continuous variables were assessed using spearman 's correlation coefficient ( r ) . for assessing the relationship between categorical variables and hrqol scores , kruskal - wallis test was used .
data entry and statistical analysis were performed using the statistical package for the social sciences ( spss ) software , version 17.0 ( spss , chicago , il , usa ) .
relationship between hrqol scores and continuous variables were assessed using spearman 's correlation coefficient ( r ) . for assessing the relationship between categorical variables and hrqol scores , kruskal - wallis test was used .
out of the total 124 diagnosed cases of copd , 86 ( 69.4% ) were males , 76 ( 61.3% ) were from rural areas , 68 ( 54.8% ) were practicing hinduism , 102 ( 82.3% ) were illiterate , all 38 ( 30.6% ) females were homemakers , 80 ( 65.5% ) were either current or past smokers with a mean pack years of smoking of 56 [ table 1 ] .
demographic and clinical profiles of study subjects the mean bmi of patients was 18.9 kg / m .
clinical characteristics showed a mean duration of illness of 2.5 years , a mean cld index of 29 , and a dyspnea severity score of 2.6 [ table 1 ] .
spirometry showed that 38 ( 30.6% ) subjects were gold stage i , 40 ( 32.3% ) were stage ii , 36 ( 29.0% ) were stage iii , and 10 ( 8.1% ) were stage iv [ table 2 ] .
spirometry results of the study subjects the mean symptom , activity , impact , and total score observed were 49.54 , 41.47 , 33.53 , and 38.89 , respectively .
the scores showed significant impairment in all three domain measures , i.e. , symptoms , activity , and impact , when compared with reference values [ table 3 ] .
significant negative correlation was found between lung function as measured by spirometry and qol scores across all domains [ table 4 ] .
quality of life scores of copd patients correlation of lung function with sgrq - c scores age , duration of illness , cld index , dyspnea grade , and exposure index had a statistically significant positive correlation with qol scores across all domains .
pack years of smoking had a statistically significant positive correlation across all domains of qol scores except the domain of activity .
bmi was not found to have a statistically significant correlation with qol scores [ table 5 ] .
correlation of continuous variables with sgrq - c scores standard of living was found to have a statistically significant association with qol scores except the activity domain .
area of residence , education , and gender did not affect the qol scores in a statistically significant manner [ table 6 ] .
the study showed an impaired qol among 124 copd patients using a disease - specific questionnaire ( sgrq - c ) .
qol was impaired across all domains ; however , symptom domain was the most affected while impact domain was the least affected .
this study highlights that indian copd patients suffer somewhat similar reductions in qol as do copd patients from other countries , as reported previously .
. this could be due to the fact that these studies were conducted in a hospital - based setting compared to a home - based setting in our study .
since hrqol is an individual 's own perception , it may be affected in a hospital - based setting . in our study , 78 of the 124 patients were suffering from stage i or stage ii disease with many of them diagnosed for the first time ; this was possible because of the community - based cross - sectional nature of our study . in copd where the initial stages show none or few symptoms , patients may not approach hospitals in the early stages and may be missed leading to an overall result , which shows worse qol . also , the patients in hospitals may be there because of exacerbation , which may lead to worsening of qol .
copd is a disease , which is mostly treated in home - based settings ; so , it is better to assess their hrqol in a similar setting .
lung functions as measured by forced expiratory volume in 1 s ( fev1 ) and ratio of fev1 and forced vital capacity ( fvc ) , i.e. , fev1/fvc showed that the poorer the lung function , the lower the patient 's qol .
this association was anticipated and has been reported in multiple studies . as grading copd in various stages of severity
is based on fev1% , these findings also indicate that severe stages of copd are having poorer qol .
smoking is a known etiological agent for copd and increased exposure leads to severe stages of disease leading to poor qol .
smoking has also been shown to independently impact qol in a negative way regardless of the presence of copd .
authors have reported that smoking cessation has been shown to improve qol scores and a reduction in symptoms related to copd .
this highlights the necessity for active interventions by health professionals to help copd patients quit smoking as a primary tool for the adequate management of copd and the patient 's qol .
previous studies have shown varied results in this regard . some have shown that underweight patients have worse health status than patients of normal weight ; similar to us , some have mentioned no association while others have shown that overweight patients have worse qol . among sociodemographic variables , age and socioeconomic status had a significant impact on qol . with increasing age , qol worsened .
some have shown results similar to us , with many reporting no correlation between age and qol .
the reason can be poor care - seeking attitude and compliance with treatment as copd requires regular and costly treatment , which poor people may find difficult to afford .
area of residence , gender , and education did not impact qol in a significant manner .
gender has been shown to impact qol in many studies with females reporting poor qol .
however , similar to us , some other authors have shown that gender plays no role in the qol of copd patients .
education has been reported to impact qol scores but was it was not so in this study .
the reasons for these are not apparent from our data but may be due to the different social structure and appreciation of education among the indian population .
also , one major drawback is that we did not look for other comorbidities , which may also impact qol as has been shown in previous studies .
qol is impaired in patients with copd and it worsens with increasing severity of the disease . worsening lung function , increasing age and duration of illness , severity of symptoms , worsening dyspnea , and lower socioeconomic state led to decreased qol in copd patients .
as copd is a slowly progressive illness , which is incurable and the amount of improvement in lung function is minimal we need to increase our focus on potentially more treatable aspects of qol , which may lead to a much more effective care of cop patients .
while evaluating of copd patients , due importance needs to be given to qol measurement similar to that given to pulmonary function test .
there is a need for further research to assess the impact of social and family support and pulmonary rehabilitation program on qol of copd patients in india .
one major reason for copd among females in developing nations such as india is the exposure to biomass fuels . in particular , for female patients the impact of pattern of biomass fuel exposure on qol needs to be studied .
background : chronic obstructive pulmonary disease ( copd ) is characterized by airflow limitation that is not fully reversible . 
 it is an incurable disease with improvement in quality of life ( qol ) as a major focus area for management . 
 this study assesses the qol of copd patients and the factors affecting it.materials and methods : all 124 patients diagnosed with copd in a larger cross - sectional study to determine the prevalence of copd were assessed for their qol using st . 
 george 's respiratory questionnaire for copd patients ( sgrq - c ) . 
 spirometry was performed to assess lung function and diagnose copd . 
 chronic lung disease ( cld ) severity index was used to assess the severity of symptoms and the medical research council questionnaire was used to assess the severity of dyspnea . 
 sociodemographic data regarding the patients were also recorded.results:patients with copd showed significantly reduced health - related quality of life ( hrqol ) . 
 cld estimate for severity of lung disease and the medical research council assessment for dyspnea and the duration of illness showed a highly significant positive correlation with hrqol . 
 there was a statistically significant negative correlation between lung function and sgrq - c score 
 . increasing age , increased quantum of smoking , and lower socioeconomic status were correlated with poorer hrqol . 
 no association between qol and education , body mass index ( bmi ) , and gender was observed.conclusion:this study showed that indian patients with copd had reduced hrqol . 
 poor lung function , increased disease duration and smoking , and worsening symptoms impacted hrqol negatively .