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 Table of Contents  
ORIGINAL ARTICLE
Year : 2018  |  Volume : 3  |  Issue : 2  |  Page : 67-74

Shifting pattern of diabetes among the elderly in India: Evidence from the national sample survey organization's data, 2004–2014


1 Achutha Menon Centre for Health Science Studies, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India
2 Department of Maternal Newborn Child and Adolescent Health, World Health Organization, Geneva, Switzerland

Date of Web Publication26-Jun-2018

Correspondence Address:
V Raman Kutty
Achutha Menon Centre for Health Science Studies, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram - 695 011, Kerala
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jncd.jncd_37_17

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  Abstract 


Objective: The objective of this study was to compare the pattern and trends in the prevalence of self-reported diabetes mellitus among the elderly in India, 2004–2014.
Research Design and Methods: The required data were extracted from National Sample Survey Organization's (NSSO) 60th round in 2004 and 71st round in 2014. Self-reported morbidity information of elderly with reference period of 15 days before the survey has been used for the analyses. From NSSO 2004, a total of 35,569 elderly persons were included in the study, and from NSSO 2014, a total of 28,397 elderly persons were included in the study. Age- and sex-standardized prevalence rate was calculated to make valid comparisons across two time periods.
Results: The prevalence of self-reported diabetes has increased more among elderly males than among elderly females during 2004–2014.The increase in prevalence percentage is more among young old than the rest. There is a clear-cut rural–urban differential in the burden of diabetes in India. The eastern and southern regions of India marked a higher prevalence as well as increase in diabetes prevalence than the rest of the nation. Those with diabetes are also likely to be burdened by the existence of other chronic conditions such as heart disease and hypertension when compared to persons without diabetes. This burden is higher for women.
Conclusion: The prevalence of self-reported diabetes appears to have increased and is higher among males. The apparent rural–urban and regional variations can be attributed to urbanization-induced lifestyle changes, increasing access to screening and treatment and reporting bias.

Keywords: Diabetes mellitus, elderly, epidemiology, India, prevalence, type 2


How to cite this article:
Kutty V R, Dilip T R, Archana A R, Gopinathan S, Ramanathan M. Shifting pattern of diabetes among the elderly in India: Evidence from the national sample survey organization's data, 2004–2014. Int J Non-Commun Dis 2018;3:67-74

How to cite this URL:
Kutty V R, Dilip T R, Archana A R, Gopinathan S, Ramanathan M. Shifting pattern of diabetes among the elderly in India: Evidence from the national sample survey organization's data, 2004–2014. Int J Non-Commun Dis [serial online] 2018 [cited 2019 Sep 21];3:67-74. Available from: http://www.ijncd.org/text.asp?2018/3/2/67/235211




  Introduction Top


Studies from various parts of India report the prevalence of type 2 diabetes mellitus between 2% and 5% among rural and between 5 and 15% among urban populations.[1],[2],[3] Urbanization may increase the actual prevalence as well as lead to greater awareness and reporting of diabetes. Increasing age of the population is one of the driving forces behind the increase in diabetes prevalence.[4],[5],[6] This is expected to go up in the future, as India has a steadily ageing population. The country is also urbanizing rapidly, as is evident from the 2011 census data.[7] Among the elderly, diabetes mellitus is a major contributor to the expenditure on health care, both in itself and as a result of complications it gives rise to.

Although diabetes is a major health problem among the elderly, there are very few studies on diabetes mellitus among elderly persons in India that draw from a nationally representative sample; most studies report on small, defined populations. Hence, the overall pattern of its prevalence among the elderly in the country remains a matter for conjecture.[8] The periodic surveys of the National Sample Survey Organization (NSSO) offer an opportunity to study the trends in prevalence of self-reported diabetes mellitus in the older persons in a nationally representative population. Although the NSSO surveys capture only the prevalence of self-reported diabetes mellitus, this represents the “burden of treatment,” as treatment is initiated by only those who are aware of their disease status. Since diabetes is a significant contributor to the cost of care among elderly,[9],[10] it is important to track the growing burden due to this ailment in India.

In this paper, we attempt to compare the pattern and trends in the prevalence of self-reported diabetes mellitus among the elderly in India, using data from the health rounds of NSSO 2004[11] and NSSO 2014.[12] The prevalence is examined with respect to other sociodemographic axes such as age, sex, place of residence, and region of residence within the country for both points in time. The existence of specific comorbidities associated with diabetes mellitus is also examined.


  Design and Methods Top


The NSSO undertakes a nationally representative survey of health and morbidity, once in 10 years. Data from the 60th round for the period 2004 and the 71st round for the period 2014 of NSSO surveys of morbidity were considered to examine the changes in the prevalence of diabetes mellitus among the elderly over the decade. The surveys use a two-stage stratified study design. Census villages and urban blocks form the first-stage units for rural and urban areas, respectively. Households constitute the second-stage units. All individuals within the selected households are included in the survey.

Data from the NSSO surveys are presented in 11 blocks or sections of information. From among these 11 blocks, information on household characteristics, demographic particulars of household members, and former household members who died during last 365 days and particulars of spells of ailments of household members during the last 15 days (including hospitalization) have been considered for this analysis. Individual unit level information about characteristics including morbidity experienced during the past 15 days was merged with the household level information to obtain the data file for analysis. The results from the analysis were matched with those in the national reports of the NSSO for the specific categories by way of validation.[11],[12]

In the 60th round, 383,338 individuals who were alive at the time of survey and 1717 individuals who had died during the 1 year preceding the survey were included in the study. Persons aged 60 and above in this group numbered 34,831 who were alive and 738 persons who were dead (excluding 15 dead persons whose ages were missing). Thus, for the 2004 period, the number of participants included in the analysis was 35,569. For the 71st round, there were 333,104 individuals who were alive at the time of survey and 2395 who had died in the 1 year preceding the survey. The elderly, aged 60 and above, in this group, consisted of 27,245 persons who were alive and 1152 who were dead, resulting in 28,397 persons being included for analysis of diabetes among the elderly for the 2014 period.

Categorization of households in terms of sources of income

Households were categorized by source of income for both rounds. The sources were classified for rural areas as “self-employed in nonagriculture,” “agricultural labor,” “other labor,” “self-employed in agriculture,” and “others.” In urban areas, the categories included “self-employed,” “regular wage/salary,” “casual labor,” and “others.”[13] Sources of income for the household were not categorized in a similar manner in the 60th and 71st rounds.[14] To synchronize, the categories across two time periods, “self-employed in nonagriculture” and “regular wage/salary,” for rural areas during the period 2014 were merged into a single category as “self-employed in nonagriculture.”

Method of age–sex standardization

The age–sex distribution of the population aged 60 and above in the 60th round (2004) was used to standardize the prevalence rates in the 71st round (2014). We applied direct standardization using this age–sex distribution to obtain comparable prevalence rates for 2014.[14],[15] For other tables also where the distribution of comorbidities with diabetes are reported, the 2014 rates have been standardized using direct standardization with the age–sex distribution of the persons reporting diabetes in 2004.

Axes of analysis

The rural areas account for 71% of the population of India.[16] Hence, we looked for rural–urban differences in diabetes prevalence among the elderly. Diabetes carries with it the burden of comorbidities such as hypertension, skin disorders, and tuberculosis.[17],[18],[19] In addition, the long-term sequelae of diabetes include diseases of kidney and urinary system, visual problems, diseases of joints and bones, neurological disorders, and locomotor conditions.[20],[21] Heart diseases could be a comorbidity of diabetes as many of the risk factors for diabetes and heart diseases are the same. Alternatively, heart disease could be one of the long-term sequelae of diabetes. We included heart diseases, hypertension, disorders of skin and tuberculosis as potential comorbidities, and diseases of kidney/urinary system, visual problems (glaucoma, cataract and visual problems including blindness not related to cataract), and other conditions related to diabetes such as disorders of joints and bones, neurological disorders, and locomotor problems as the long-term sequelae.


  Results Top


Prevalence of self-reported diabetes mellitus among the elderly is computed for two time periods 2004–2014 shown in [Table 1]. The prevalence of diabetes has gone up, more for males than females. The highest increase in prevalence seems to be among the young old (aged 60–64) where the prevalence increased by 3.5 percentage points. This increase in prevalence is higher in urban areas, though more people live in rural areas. In terms of nature of employment, the increase in prevalence is highest among those in the “others” category (those possibly not currently employed) in both rural and urban areas. Note that the “others” category, especially in urban areas, are likely to be relatively affluent ones, where major share of household income is from pensions/remittances from family members/interest from bank deposits and other similar sources.
Table 1: Prevalence of self-reported diabetes mellitus among persons aged 60 and above by socio-demographic characteristics, India, 2004-'14

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The rural–urban divide in diabetes prevalence in old people is examined by age and sex shown in [Table 2]. There are differences in the age–sex pattern of self-reported diabetes by place of residence. The increase in prevalence in rural areas is among the old old (aged 70–74 and 75 and above) for men and among young old in urban areas (aged 60–64 and 65–69) for both men and women.
Table 2: Age-standardised prevalence of self-reported diabetes mellitus, among persons aged 60 and above, by sex, age and place of residence, India, 2004-'14

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[Figure 1] represents the difference in prevalence of self-reported diabetes by sex across six regions of India for the two time periods. The highest increase over time is in the east and southern regions for both men and women.
Figure 1: Prevalence of self-reported diabetes mellitus among persons aged 60 and above by sex and region, India 2004–2014

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The burden of the number of comorbidities and long-term sequelae with diabetes by sex and place of residence across two-time points is given in [Figure 2].
Figure 2 (a-d): Distribution of persons aged 60 and above with self-reported diabetes mellitus and presence of selected other chronic comorbidities by sex and place of residence, India 2004–2014

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  Discussion Top


Prevalence of diabetes is on the rise in most parts of the world, as it is in India.[22],[23] We can assume that this trend would be especially manifest among elderly persons. By looking at nationally representative data in 2004 and 2014, we try to assess the impact of the change in the elderly and how it is distributed. What is evident from these data is that between 2004 and 2014, there has been an increase in the prevalence of self-reported diabetes mellitus among the elderly in India, across almost all the axes that we looked at. In some categories, it has increased two-fold or even more. The notable increases in prevalence of diabetes are across the following subgroups: urban residents (7%–11%), “old old” or those above 75 years of age (3%–5%), scheduled caste (1%–5%), and the category “others” among “sources of income for the household” in both urban (8%–15%) and rural (3%–9%).

There could be three reasons contributing to the increasing prevalence of self-reported diabetes mellitus among the elderly in India, if we exclude any bias in selection of the sample: (1) an increase in the incidence of diabetes mellitus among the elderly; (2) increased awareness, diagnosis, and reporting of diabetes mellitus among the elderly; and (3) increased survival of diabetic patients into old age due to better management of diabetes. We can safely assume that all three have contributed to this observed trend, though it is difficult to disaggregate the proportionate contribution of each reason. Greater survival of diabetics may have contributed largely to the increase in self-reported diabetes mellitus among the “old old” or those above 75 years, whereas the increase among urban residents may reflect, at least in part, a greater awareness and reporting.

The increasing prevalence of diabetes among elderly also has a differential impact on selective sections of the population. If we look at the sex differences in prevalence, we find that in 2004, there appears to be no consistent pattern. In subgroups defined by age, place of residence, and region, sex differences are minimal and inconsistent in 2004. However, by 2014, there is an emerging pattern, with most subgroups reporting higher prevalence among males. This sex difference is especially pronounced in subgroups where the prevalence for both is high, such as urban, as well as regions such as west and south. This could again be a bias in diagnosis or reporting: Diabetes mellitus among men may be recognized and diagnosed earlier than those in women. It is well known that in the case of other ailments also, men are more likely to access the health system compared to women. If this is true, it has implications for access to treatment between the sexes and to gender equity in general.[24],[25],[26] The increase in urban prevalence is partly attributable to changing lifestyles among urban people, some of it by choice and some because of lack of choice and partly due to better survival of diabetic patients due to better management of diabetes in the urban areas. With India urbanizing at a rapid rate, making services available to this growing population of people living with diabetes at an affordable cost should be a serious concern to health planners.

Among geographical regions in India, data from 2004 show that prevalence is highest in the South and the West. The all India prevalence has almost doubled in the intervening years, from 3.1% to 5.8%. However, the South seems to account for much of the increase: while it has doubled in prevalence from 6.7% to 13.9%, the Western region has more or less maintained the prevalence reported in 2004. While the East has increased, the North reports the same levels as before. The North East actually shows a fall in prevalence to almost negligible levels. The wide variation in self-reported diabetes mellitus can be attributed to reporting biases or access to health care or could be due to variation in modifiable risk factors.[27],[28] How much of this variation between 2004 and 2014 can be attributed to reporting bias is difficult to assess. We would expect higher proportion of reporting in 2014 compared to 2004; by this criterion, the fall in the North East is difficult to explain. This does throw some doubt on to the validity of the method of assessment.

Diabetes mellitus is well known to bring in its wake other chronic conditions such as coronary heart disease, kidney disease, and retinal problems, as well as to be associated with infections such as tuberculosis. Overall, detection of comorbidities and long-term sequelae seems to have resulted in a greater prevalence of diabetes mellitus with comorbidities among older women rather than older men, when we compare the data from 2004 to 2014. It is difficult to confirm whether this reflects a true difference in disease status or better survival status of females.

People of Indian origin have been shown to have increased risk for diabetes mellitus in many studies from across the world.[29],[30],[31],[32] Within India itself, in the intervening years between 2004 and 2014, two sociodemographic phenomena have compounded this trend: Rapid urbanization [33] leading to change in lifestyles toward one favoring less physical activity and a steadily aging population. The established fact of geographical diversity in diabetes mellitus prevalence [34] is true for the elderly also and is observed in this study. Data on self-reported diabetes mellitus seem to indicate that the burden of this chronic condition, and the complications and comorbidities that may be brought on by diabetes mellitus, can be expected to increase steadily in the future. An examination of the variation in risk factors would enable better understanding, but this falls beyond the scope of the datasets used for analysis.


  Conclusion Top


India has declared its vision to bring universal health coverage to its citizens.[35] This will be a significant step toward achieving equity in health in the country. Under this broad goal, the elderly have to be singled out for special treatment as they perhaps share the greatest burden of chronic noncommunicable diseases. Diabetes will be a significant challenge to be overcome to achieve this commendable goal. The burden of cost as well as care it will imply for the health services is one that should give food for thought to health policymakers and administrators. There may be a need to focus on prevention strategies targeting those at younger ages with a view to reducing the chronic disease burdens at older ages.

Acknowledgment

This paper is part of a research that has been funded by a grant no. 5221 of Sree Chitra Tirunal Institute for Medical Sciences and Technology from the “Women Component Plan” of the Ministry of Science and Technology, Government of India titled “Impact of type 2 Diabetes on women's lives and well-being.” We thank successive Directors of SCTIMST for support extended, as well as Prof. K R Thankappan, former HOD, Achutha Menon Centre, SCTIMST. The contributions of Mr. Bevin Vinay Kumar Vijayan, Ph.D student, AMCHSS, SCTIMST are acknowledged for the development of the figures used in this paper. We are also grateful to Dr. William Joe and Dr. Udaya S Mishra for their inputs regarding the intricacies of NSSO data analysis.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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