DEPARTMENT OF HEALTH & FAMILY WELFARE
	HIMACHAL PRADESH Himachal Burden of Disease -  A Study

1          Executive Summary:

 The Burden of Disease estimates study was undertaken in the state of Himachal Pradesh in the year 2001-02. The first estimates of Burden of Disease (BOD).was made on the basis of secondary data available on mortality and morbidity. The morbidity data for the state has been compiled from the morbidity report of the state for the year 1999.The epidemiological estimate of incidence, age of onset and during are taken from Indian estimates given in Global Burden of Diseases Study 1996.The source of mortality data is the annual statistical report prepared by Government of Himachal Pradesh for the year 2000.The total population of the state has been taken from primary censes abstract for 2001.The age and sex composition of the state is based on the average of the annual SRS report of the past five years (1993-1998).The summary of estimation for BOD for year 2001 is given below.  

1.      The total “Disability Adjusted Life Year “  ( DALYs ) lost in Himachal Pradesh were 2305295;55.8% (1288461) were lost in males and 44.1 % (1016834) in females.

2.      The total DALYs lost per 1000 population in Himachal Pradesh were 379 ,which was slightly higher than India (344 per 1000 population) and lower  (537 per 1000 population ) as compared to rural Andhra Pradesh. The estimates of Himachal Pradesh are comparable to Nepal (349 per 1000 population).

3.      Among the children (0-4 years), diarrhoeal diseases, low birth weight and lower respiratory infections are still the leading causes of disease burden.

4.      Among the reproductive age group (15-45 years) ,road accidents ,other unintentional injuries, iron deficiency anemia, tuberculosis, chronic obstructed pulmonary diseases and upper respiratory infection are the leading causes of diseases burden.

5.      Among the elderly (more than 60 years) ,the main causes of disease burden are cronic obstructed pulmonary disease, ischaemic heart disease ,tuberculosis ,asthma, other infectious diseases and other unintentional injuries.

6.      The overall leading causes of disease burden in both sexes are chronic obstructed pulmonary disease, asthma iron deficiency anemia, dental caries ,other unintentional injuries and diarrhoeal diseases.

7.      The premature mortality and disability (YLL:YLD) ratio is higher among males as compared to females in different age groups. It means that burden of disease is more contributed by the premature mortality compared to disability in them.

8.      The common leading causes of premature mortality (YLL) in males and females are road accidents, diarrhoeal and other infectious diseases , ischaemic heart disease ,self inflicted and other unintentional injuries, tuberculosis and chronic obstructed pulmonary disease.

9.      The common leading causes of disability (YLD) in both sexes are chronic obstructed pulmonary disease ,ischaemic heart disease, diarrhoeal diseases ,and other unintentional injuries.

The current analysis cannot be considered to be exhaustive on any count but it certainly gives interesting leads and suggestion for improvement. Deficiency in availability of local data is highlighted to draw attention to the need for improving vital statistics, cause of  death and epidemiological surveillance system. To overcome the inadequacy in available data ,a survey of cause of death is being carried out in Himachal Pradesh by using 30 Cluster techniques covering approximately 1.5 lakhs population .By the end of this year, the final estimates for burden of disease and recommendation will be made after the completion of this survey.  

2.         Introduction  

The Global Burden of Disease (BOD) was first estimated by Christopher Murray in 1992 with expectation that result will help to bring about the reform in health sector ,planning and developments, Burden of disease is now sought to be quantified by summary measures, which combines information on mortality morbidity and disability.  

The Word Bank in collaboration with WHO sponsored the first BOD study by the team led by Christopher Murray to provide the disease burden estimated for World Development Report 1993.The general willingness to embark on estimation despite enormous deficiencies in data, the tenacity to provide methodological solutions to indirectly estimate epidemiological parameters, the use of internal consistency tools to seek more plausible estimates and to lay emphasis on the overall picture rather than on single diseases entity or solitary interventions were the main hallmark of study. It provides lot of scope for health policy analysis. The study of disease prevalence helps in decoupling epidemiological assessment from advocacy. The single measure of the health outcomes enables comparison of cost effectiveness of all interventions within the health sector.  

Disability –Adjusted Life Years(DALY) that includes both the mortality as well as the morbidity component has been developed as the measurement unit for the global burden of disease study. This was build upon the time based measures of health status that also incorporated non-fatal health outcomes. It is a measure of health gap from a chosen life expectancy in perfect health. Disability associated with the state of perfect health or well being is assigned a weight of 0 and disability due death is assigned a weight of 1.Annual incidence of DALY is computed from demographic data like age and cause specific mortality as well as from the descriptive epidemiological knowledge about the age of onset, incidence and duration of different diseases. DALY estimation requires collaboration of skills between experts from various disciplines having knowledge of economics, demography and epidemiology. The incorporation of age weighting and discounting in DALY measure has often been criticized. he formulation presented by Murray (1996) allows computation of DALYs without age weighting and discounting.

3.         Methodology:  

3.1       General Demographic inputs for the estimation of disease burden in Himachal Pradesh.  

DALY has two components namely years life lost due to premature mortality (YLL) and years life lost due to disability (YLD).The local data essential for the mortality (YLL) component of disability-adjusted life years ( DALY ) are the number of deaths by age ,sex and average age at death within respective age groups. For the estimation of disability (YLD) component of disability –adjusted life years. (DALY) however no demographic inputs are directly required. Identifying the midpoint of respective age intervals can approximate age at death. YLDs require the computation of number of incident cases, and other descriptive epidemiological parameter estimates like age at death, duration of the disease etc. Deaths are thus the only indispensable set of demographic estimates essential for computation of DALYs. Construction of local life table is useful to cross check the stock of the demographic estimates that may be required at different stages of burden of disease estimation.  

The population censes is the natural source of the population data, but the census in our country is done once in 10 years. If the reference years of the National Burden of Disease (NBD) study coincides with the census year, then the figures mentioned in the census can be taken and used straightway. Primarily census abstracts gives the total population counts in five age groups. Thus it is necessary to arrive at age –specific distribution of population becomes mandatory from which interpolation can be done. In India , Sample Registration System (SRS) done once in six months provides an estimate of age composition. Sample design, registration and validation methodology of SRS has been published by the Registrar General , India . For Himachal Pradesh ,total male and female population for the state has been taken from the primary census abstract. The age –sex composition of the population has been based on average of the annual SRS report of past five years(1993-1998).  

3.2              Demographic profile for Himachal Pradesh  

Himachal Pradesh has a total population of 60,77,247(2001 census).Average density of population is 109 persons/sq. Km. and ranges from 2 in district spiti & Lahaul to 369 in district Hamirpur. Majority of the population is rural (91.3%).Most of the villages have small dwellings with population less than 500 (81.5%).Only 5 villages have population greater than 5000.The state’s population tabulated by the five age groups seven age groups and five –years age groups are given in appendix1(A-C).

 3.2.1        Fertility changes in Himachal Pradesh  

Fertility is gradually coming down over the years as is evidenced by numerous surveys. The state has achieved a considerable success in bringing down the CBR from 37.3/1000 in 1971 to 23.8/1000 as per SRS data 2001.(Table 1)  

Table 1: Crude Birth Rate of Himachal Pradesh from 1971-2001  

 There has been also steady decline in the TFR in the state. NFHS-I estimated TFR for women in age group 15-49 yrs at 3 children in 1992 whereas NFHS-II shows the estimates as 2.14 children per woman.  

3.2.2    Mortality changes in Himachal Pradesh  

Crude Death Rate (CDR) has been declining gradually since 1971.It was 15.6/1000 in 1971,according to SRS estimate in 2001 it is around 9/1000.  

Table 2:Crude Death Rate of Himachal Pradesh from 1971-2001  

The state thus has been experiencing a gradual decline in mortality and gradual decrease in fertility. Even though the population has been continuously rising as shown in the figure 1,the age composition of state population has remained fairly stable. Precise information on external migration was that its net effect on size and structure of population would be negligible.

Reasonably accurate data on age composition of local population helps in identifying closely related stable population, by comparing the age composition of the local population with age composition of the stable  populations. For Himachal Pradesh ,age composition of the study population was. compared with the age composition of Coale  and Demeny stable population models from West pattern of mortality. The index of dissimilarity was used to compare the agreement between the age patterns. Identification of stable population model becomes the first approximation of mortality estimation for computation  of  burden of disease.

 3.2.3        Morbidity data

 Morbidity data for the state has been compiled from the morbidity report 1999.Morbidity data reporting has been done from 544 institutions of the state, which includes both indoor admission as well as outpatient department consultation. They have been classified into five age groups for calculation of YLD component of DALY into same three broad groups. Mapping of non-medical list(NML) cause of death to single burden of disease list (BOD) causes is given in appendix 2.Epidemiological estimates of Disease study Murray and Lopez,1996 for India region. The data were fed into the software programme “WHO Burden of Disease Analysis Project” developed by HIS , Hyderabad and results tabulated.

 3.2.4        Mortality data

 The vital registration system of state of deaths and births getting registered is considered satisfactory. Hence for the present study data has been taken directly as reported by state government statistical department.

 The source for mortality data is the annual statistical report prepared by  the Govt. of HP for  the 2000 as shown in appendix 3 & 4.A total of 31,915 deaths occurred in the years, of which there were 12,735 female deaths and 19,180 male deaths. These deaths have been classified by seven age groups for YLL component of DALY calculation into three broad classifications of Group I,II and III as described below.  

Group I includes infectious ,maternal ,prenatal and nutritional diseases.

Group II includes non-communicable and congenital diseases.

Group III includes injuries and accidents.

 Age at Death  

Age at death is the required input for calculation of YLL. Age at death(a) in each age interval is arrived at as follows:

A= Initial age of the interval + A_x-(x+n)

Where A_{x-(x+n)  =}  Average no. of years lived in the age interval by those dying during the interval x-(x+n).

 4.         Results

 Results presented in this section are based on general demographic estimates of mortality level and population, and causes of onset and duration are taken from the global burden of disease study (Murray & Lopez,1996) for the India region. Estimates of DALYs lost. YLD and YLL by cause, age and sex for the state are provided in appendix 5,6 & 7.  

Total DALYs lost /1000 persons were estimated to be 379 for the year 2001 in Himachal Pradesh, which was lower than the rural A.P. (537/1000 persons) and slightly higher than India as a whole(344/1000 persons).  

4.1 Top Ten Causes of Diseases Burden

 The top ten causes of diseases burden in different age group in males and for females are shown in table 3 and 4.Among children of 0-4 years still diarrhoeal diseases ,low birth weight and lower respiratory infection are leading causes of diseases burden. Among  the reproductive age group, road accident and other unintentional injuries, iron deficiency anemia ,tuberculosis ,chronic obstructive pulmonary diseases and upper respiratory infections are leading cause of diseases burden.

 Table 3: Top ten causes of burden od diseases ( DALYs )among males of Himachal Pradesh

Table 4: Top ten causes of burden of diseases ( DALYs )among females of Himachal Pradesh

 The overall top ten causes of berden of diseases among males and females are shown in table 5,figure 3 & 4. Respiratory infections, diarrhoeal  diseases, iron deficiency anemia, tuberculosis, chronic obstructive pulmonary diseases and road accidents are six major causes of disease burden in both sexes. The disease burden on account of iron deficiency anemia and tuberculosis in both the sex is mostly in the age group 15-44 years. This calls for early diagnosis and treatment for both the conditions.

Table 5:          Leading causes of diseases burden (DALY) in male and female of Himachal Pradesh.

 Top ten causes of burden of diseases ( DALYs )among males

 Top ten causes of burden of diseases (DALYs) among females

 The leading causes of DALYs lost in different age group are shown in table 6.

1. Lower respiratory infection,diarrhoeal diseases and low birth weight oredominantly affects infants and children.
2. Tuberculosis continues to be the leading cause of death in group I diseases.
3. Among the non communicable diseases ischemic heart diseases ,COPD and digestive disorders were the leading causes both among the males and females .Other causes include cerebrovascular diseases and asthma as well as the cancers.
4. Falls ,roads accidents and other unintentional injuries were the leading causes of death among injuries and accidents.

Table 6 : Leading DALYs lost in different ages.