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Socio-demographic factors of COPD mortality in India

Published:March 11, 2020DOI:https://doi.org/10.1016/j.cegh.2020.02.028

      Abstract

      Objective

      The epidemiology of Chronic Obstructive Pulmonary Disease (COPD), one of the major killers in India, has been inadequately studied. There is dearth of national data and analysis on its associates. The present article aims to find out socio-demographic factors associated with it.

      Materials and methods

      Data taken from National Family Health Survey (NFHS 4) (2015-16), Global Adult Tobacco Survey (GATS) 2: India 2016-17 and India: Health of the Nation's States were analyzed with scatter plot and multivariate regression.

      Results

      COPD mortality has negative relationships with use of clean fuel and economic condition and positive relationships with smoking and Second Hand Smoking (SHS). On regression, use of clean fuel reduces and SHS at home increases COPD deaths.

      Conclusion

      For preventing deaths from COPD, focus should be on up scaling use of clean fuel and improvement in economic condition.

      Keywords

      1. Introduction

      Chronic Obstructive Pulmonary Disease (COPD), a progressive disease of the respiratory tract, is responsible for 3.17 million deaths worldwide. More than 90% of these deaths occur in low and middle income countries. Another 251 million people are suffering from the disease globally.
      • World Health Organization
      Chronic Obstructive Pulmonary Disease (COPD) Fact Sheet No 315.
      Considered as a preventable disease, it causes 8.7% of the total deaths in India and morbidity to 55.3 million people, contributing 4.8% of Disability Adjusted Life Years (DALY) in the country. In fact, from 1990 to 2016, the crude prevalence of COPD has increased by 29%.
      • India State-Level Disease Burden Initiative CRD Collaborators
      The burden of chronic respiratory diseases and their heterogeneity across the states of India: the Global Burden of Disease Study.
      As Sustainable Development Goals look to reduce premature mortality from Non Communicable Diseases (NCD) including COPD by one third by 2030, it is vital to identify the modifiable risk factors and address them strategically.
      Various studies conducted at different parts of the country brought focus on this chronic respiratory disease. However, only a handful of them used spirometry as mode of diagnosis, thereby limiting the scope of further utilization of the study findings.
      • Rajkumar P.
      • Pattabi K.
      • Vadivoo S.
      • et al.
      A cross-sectional study on prevalence of chronic obstructive pulmonary disease (COPD) in India: rationale and methods.
      Different factors have, by now, been implicated in the causation of COPD deaths, tobacco and air pollution being two major preventable causes amongst them. It has been calculated that three fourth of the DALY contributed by COPD could be ascribed to these two factors.
      • India State-Level Disease Burden Initiative CRD Collaborators
      The burden of chronic respiratory diseases and their heterogeneity across the states of India: the Global Burden of Disease Study.
      Not only smoking, exposure to second hand smoking (SHS) has also been responsible for precipitating COPD.
      • Office on Smoking and Health
      Respiratory effects in children from exposure to secondhand smoke.
      The role of financial condition for deciding the outcome of the disease was also established. In fact, there are several other factors like presence of diagnostic facility and treatment options which decides access to treatment and subsequent outcome.
      In an effort to find out the associates of COPD mortality, the present paper aims to analyze certain socio-demographic factors.
      The objective was to find out if there is any association between COPD and smoking, smokeless tobacco, use of clean fuel, per capita income and exposure to SHS in Indian population.

      2. Materials & methods

      National Family Health Survey (NFHS 4) (2015-16), Global Adult Tobacco Survey (GATS) 2: India 2016-17 and India: Health of the Nation's States – these three reports were used for collecting data on all the variables.
      • International Institute for Population Sciences (IIPS) and ICF
      National Family Health Survey (NFHS-4), 2015-16: India.

      Tata Institute of Social Sciences (TISS), Mumbai and Ministry of Health and Family Welfare, Government of India. Global Adult Tobacco Survey GATS 2 India 2016-2017.

      • Indian Council of Medical Research
      • Public Health Foundation of India
      • Institute for Health Metrics and Evaluation
      India: Health of the Nation's States - the India State-Level Disease Burden Initiative.
      While NFHS is conducted at an interval of 5–10 years, GATS 2 was conducted 7 years after GATS 1. The report India: Health of the Nation's States is based on Global Burden of Disease Study (GBD) 2016.
      Among different factors, smokeless tobacco (SLT) use, smoking, SHS at work and home, mortality rate due to COPD, clean fuel and Net State Domestic Product (NSDP), as parameter for economic condition for different states were taken into account. NFHS 4 considered people between 15 and 49 years while GATS 2 considered people aged 15 years or above. Tobacco use considers both smoking and SLT. Clean fuel indicated electricity, Liquid Petroleum Gas (LPG)/natural gas and biogas. Data on NSDP for 2015-16 were taken from Ministry of Statistics and Programme Implementation, India.

      MOSPI Gross State Domestic Product. Ministry of Statistics and Programme Implementation.

      Scatter plot was used for testing association between death rate of COPD and independent variables. Multivariate regression was used for finding out factors determining mortality rate due to COPD. Tobacco use, being a composite variable for SLT use and smoking, was not considered for regression. P value < 0.05 was considered significant. Predictive Analytics SoftWare (PASW) for Windows software was used.

      3. Results

      The highest and lowest mortality rate were recorded in Rajasthan and Nagaland (111/100,000 population and 18/100,000 population, respectively). Most of the states with high death rates were in north India. Highest smoking rate was noted in Mizoram (34.4%) and Meghalaya (31.6%). Highest tobacco use was seen in Tripura (64.5%) and Mizoram (58.7%). Mizoram (84.1%) and Meghalaya (76.8%) recorded highest exposure to SHS at home while Jammu and Kashmir and West Bengal (both 57.5%) saw highest exposure to SHS at work.
      Negative relations of COPD mortality was noted with use of clean fuel (Fig. 1) and economic condition (Fig. 2). Smoking and SHS share positive relationship with COPD deaths.
      Fig. 1
      Fig. 1Use of clean fuel and COPD mortality in India.
      Fig. 2
      Fig. 2Per capita National State Domestic Product and tobacco consumption in India.
      On regression, SHS at home increases and use of clean fuel reduces COPD deaths, although the relationships were not significant. SLT use was significantly associated with COPD deaths (p = 0.011).
      After controlling for other variables, higher income, too, was seen to reduce COPD mortality (Table 1).
      Table 1Multivariate analysis for COPD burden in India.
      VariablesRegression coefficient (B)95.0% Confidence IntervalP value
      Smokeless tobacco use– 1.218– 2.129 – (−) 0.3060.011
      Smoking– 0.172– 2.110–1.7660.856
      Per capita NSDP (2015–16)0.0000.000–0.0000.240
      Clean fuel– 0.177– 0.960–0.6070.645
      SHS at home0.449– 0.318–1.2150.238
      SHS at work– 0.509– 1.600–0.5820.345
      SHS = Second Hand Smoking.
      NSDP = Net State Domestic Product.

      4. Discussion

      COPD is set to become third leading cause of death globally by 2030.
      GBD 2015 Chronic Respiratory Disease Collaborators. Global, regional, and national deaths, prevalence, disability-adjusted life years, and years lived with disability for chronic obstructive pulmonary disease and asthma, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015.
      However, for estimating the burden, there is lack of consensus about working definition, thus preventing uniformity is research protocols. In one meta-analysis, no study was found to estimate such prevalence of COPD in the country.
      • McKay A.J.
      • Mahesh P.A.
      • Fordham J.Z.
      • Majeed A.
      Prevalence of COPD in India: a systematic review.
      GBD tried to fill in that gap in epidemiology.
      Earlier researchers found that COPD mortality and smoking prevalence do not always coincide.
      • Salvi S.
      • Barnes P.
      Chronic obstructive pulmonary disease in non-smokers.
      ,
      • Burney P.
      • Jithoo A.
      • Kato B.
      • et al.
      Chronic obstructive pulmonary disease mortality and prevalence: the associations with smoking and poverty--a BOLD analysis.
      The present study demonstrated the same, with states like Meghalaya and Arunachal Pradesh recording lower death rates from COPD, suggesting multi-factorial causation, particularly at a time when air pollution is causing higher deaths than smoking. COPD is 3–5 times more likely to occur in smokers.
      • Zhong N.
      • Wang C.
      • Yao W.
      • et al.
      Prevalence of chronic obstructive pulmonary disease in China: a large, population based survey.
      Among different factors, duration of smoking seems to be an important one.
      • Bai J.W.
      • Chen X.X.
      • Liu S.
      • Yu L.
      • Xu J.F.
      Smoking cessation affects the natural history of COPD.
      Quitting smoking helps in prolonging survival, as evident from previous researches, probably by relieving emphysema.
      • Bai J.W.
      • Chen X.X.
      • Liu S.
      • Yu L.
      • Xu J.F.
      Smoking cessation affects the natural history of COPD.
      ,
      • Zamarro García C.
      • Bernabé Barrios M.J.
      • Santamaría Rodríguez B.
      • Rodríguez Hermosa J.L.
      Smoking in COPD.
      As India documented a reduction in smoking prevalence from 34.6% to 28.6% among citizen aged 15 years and older, it is expected to reduce the burden of COPD in future.

      Tata Institute of Social Sciences (TISS), Mumbai and Ministry of Health and Family Welfare, Government of India. Global Adult Tobacco Survey GATS 2 India 2016-2017.

      Since SHS increased the risk of COPD mortality, the benefit of smoking reduction could be multifold.
      • Ukawa S.
      • Tamakoshi A.
      • Yatsuya H.
      • et al.
      Passive smoking and chronic obstructive pulmonary disease mortality: findings from the Japan collaborative cohort study.
      ,
      • Hagstad S.
      • Bjerg A.
      • Ekerljung L.
      • et al.
      Passive smoking exposure is associated with increased risk of COPD in never smokers.
      National Programme for Prevention and Control of Cancer, Diabetes, Cardiovascular Diseases and Stroke (NPCDCS), India's response to rising NCD burden, brings COPD under its umbrella in 2016 and provides preventive and curative care to the clients through NCD Clinics at state and district level.
      Directorate General of Health Services, Ministry of Health and Family Welfare, Government of India
      National Programme for prevention and Control of cancer, Diabetes, cardiovascular diseases and Stroke.
      Air pollution also plays crucial role for COPD mortality and morbidity. Non-smokers females in developing countries fall prey to compromise in indoor air quality from using biomass fuel for cooking.
      • Behera D.
      • Jindal S.K.
      Respiratory symptoms in Indian women using domestic cooking fuels.
      It has been estimated that exposure to air pollution from cooking contributes to 925,000 premature deaths in India annually.
      • Forouzanfar M.H.
      • Alexander L.
      • et al.
      GBD 2013 Risk Factors Collaborators
      Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks in 188 countries, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013.
      Poor ventilation, long duration spent in kitchen may in fact increase such exposure. One meta-analysis expressed concerns on the extent of indoor fuels and inadequate ventilation.
      • McKay A.J.
      • Mahesh P.A.
      • Fordham J.Z.
      • Majeed A.
      Prevalence of COPD in India: a systematic review.
      All these observations necessitate replacement of biomass fuel with a cleaner substitute. Ujjwala scheme in India aims just the same, by introducing LPG at the farthest corners of the country, with the hope that in the long run, the burden of COPD and other NCDs will come down. This has serious implications on household health and financial burdens as it would reduce loss of wages, besides decreasing medical expenditure.
      • Pillarisetti A.
      • Jamison D.T.
      • Smith K.R.
      Household energy interventions and health and finances in Haryana, India: an extended cost-effectiveness analysis.
      Notably, the state with highest death rate from COPD (Rajasthan, with 111/100,000 population) has a poor coverage of clean fuel (31.8%).
      • Indian Council of Medical Research
      • Public Health Foundation of India
      • Institute for Health Metrics and Evaluation
      India: Health of the Nation's States - the India State-Level Disease Burden Initiative.
      With a study from Ludhiana reporting higher frequency of COPD in industrial areas, the role of outdoor air pollution could again be highlighted.
      • Sharma A.K.
      • Kalra O.P.
      • Saini N.K.
      • Kelkar H.
      Pilot study of chronic obstructive pulmonary disease in an industrial town in India.
      Such pollution has also been implicated in rise in hospital admissions and death from COPD.
      • Ko F.W.
      • Hui D.S.C.
      Air pollution and chronic obstructive pulmonary disease.
      It may be mentioned that for COPD patients, existing air quality guidelines need to be tightened, as suggested by Liu.
      • Liu Y.
      • Yan S.
      • Poh K.
      • Liu S.
      • Iyioriobhe E.
      • Sterling D.A.
      Impact of air quality guidelines on COPD sufferers.
      In addition, there is need to check the extent of stubble burning and vehicular pollution in north India, with studies pointing at air pollution for exacerbating COPD cases.
      • Jiang X.Q.
      • Mei X.D.
      • Feng D.
      Air pollution and chronic airway diseases: what should people know and do?.
      ,
      • Wang B.
      • Liu Y.
      • Shao M.
      The contributions of biomass burning to primary and secondary organics: a case study in Pearl River Delta (PRD), China.
      In India, the most common form of tobacco use is chewing paan mashala/guthka (betel quid, areca nut).
      • International Institute for Population Sciences (IIPS) and ICF
      National Family Health Survey (NFHS-4), 2015-16: India.
      Many people switch to SLT, in an effort to quit tobacco. In a study on such switcher, the risk of dying from COPD was found greater than quitters, even after controlling for age and other confounders.
      • Henley S.J.
      • Connell C.J.
      • Richter P.
      • et al.
      Tobacco-related disease mortality among men who switched from cigarettes to spit tobacco.
      Nasal use of snuff has also been seen to precipitate chronic bronchitis, a variant of COPD.
      • Ayo-Yusuf O.A.
      • Reddy P.S.
      • Van den Borne B.W.
      Association of snuff use with chronic bronchitis among South African women: implications for tobacco harm reduction.
      In south east Asia, disadvantaged groups are more prone to be exposed to SLT.
      • Palipudi K.
      • Sinha D.
      • Choudhury S.
      • et al.
      Predictors of tobacco smoking and smokeless tobacco use among adults in Bangladesh.
      Inexpensive nature and social acceptability, after being added with lack of regulatory mechanisms for household production of SLT, probably makes it a client for silent epidemic.
      • Mia M.N.
      • Hanifi S.M.
      • Rahman M.S.
      • Sultana A.
      • Hoque S.
      • Bhuiya A.
      Prevalence, pattern and sociodemographic differentials in smokeless tobacco consumption in Bangladesh: evidence from a population-based cross-sectional study in Chakaria.
      There is need for putting enormous efforts for social awareness to fight this widespread problem.
      Financial condition is a close determinant of COPD outcome. With rise in the income, COPD deaths fall.
      • Burney P.
      • Jithoo A.
      • Kato B.
      • et al.
      Chronic obstructive pulmonary disease mortality and prevalence: the associations with smoking and poverty--a BOLD analysis.
      During economic downturn, Greece witnessed a hike in non-adherence of treatment, frequent exacerbations and more hospitalizations.
      • Kotsiou O.S.
      • Zouridis S.
      • Kosmopoulos M.
      • Gourgoulianis K.I.
      Impact of the financial crisis on COPD burden: Greece as a case study.
      In fact, provisions like spirometry and opinion from pulmonologists are lacking at the level of primary care in our country, thereby rendering the care to the COPD patients suboptimal.
      • Mandke A.
      • Mandke K.
      Under diagnosis of COPD in primary care setting in Surat, India.
      Probably a high number of cases remain undiagnosed, too, warranting a change in policy level for making spirometry available at the primary care setting for addressing the unmet needs in health care. Till such things happen, emphasis must be there for identifying high risk cases and referring them to centres equipped with spirometry.
      • Spyratos D.
      • Chloros D.
      • Michalopoulou D.
      • Sichletidis L.
      Estimating the extent and economic impact of under and overdiagnosis of chronic obstructive pulmonary disease in primary care.
      At the individual level, patients from lower socio-economic status usually presented late, with more frequent hospitalizations and higher mortality.
      • Gershon A.
      • Campitelli M.A.
      • Hwee J.
      • et al.
      Socioeconomic status, sex, age and access to medications for COPD in Ontario, Canada.
      ,
      • Eisner M.D.
      • Blanc P.D.
      • Omachi T.A.
      • et al.
      Socioeconomic status, race, and COPD health outcomes.
      At least four states (Rajasthan, Uttar Pradesh, Jammu and Kashmir, Tripura), from the present study, are there with low per capita income and high COPD deaths, suggesting that intervention for uplifting socio-economic status might reduce COPD mortality there.
      The present paper brings some standard data sets together to analyze the associates of COPD deaths in India. Absence of such efforts in literature is one of the strength of this article. Consideration of data on smoking, tobacco use, passive smoking at home and work separately with mortality data is another unique dimension of this study, by which it attempts to cover the full spectrum of tobacco and COPD. Being an ecological study, it was beyond the scope to determine temporal relationship between COPD death and related factors. Longitudinal study could be planned to determine the effect of PM2.5 on occurrence of COPD or related deaths. The study did not have data on airflow obstruction, an important factor for COPD epidemiology. There may be other NCDs co-existing in COPD patients, thus influencing their survival. In fact, one study suggested that co-morbidities are more likely to cause death than COPD itself.
      • McGarvey L.P.
      • John M.
      • Anderson A.M.
      • Zvarich M.
      • Wise R.A.
      TORCH Clinical Endpoint Committee
      Ascertainment of cause-specific mortality in COPD: operations of the TORCH clinical endpoint committee.
      Considering those factors was not possible in the present paper. To conclude, lack of multi-state study on COPD using standard methodology is the need of the hour to estimate the burden accurately. It should also take care of the related variables. In addition, for reducing deaths due to COPD, there is need for prevention at primary, secondary and tertiary level, with due emphasis on rehabilitation. Upcoming strategy should concentrate on the same.

      Source(s) of support

      Nil.

      Declaration of competing interest

      No.

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