Association of BMI, socioeconomic status and menarche age with anemia in rural school going adolescent girls

Background: India has the world’s highest prevalence of anemia among women and adolescent girls. Rural adolescent girls are particularly vulnerable to develop anemia. Aims and Objectives: To study the prevalence of anemia in rural school going adolescent girl sand its associated factors like BMI, socioeconomic status and age at menarche. Materials and Methods: A prospective study was carried out among 1200 adolescent girls (12-16 yrs) of 10 randomly selected government schools. BMI, Socioeconomic status by modified kuppuswami Classification, Menarche age by history and hemoglobin by cyanmethemoglobin method of all adolescent girls were obtained and analysed statistically. Results: Theoverall prevalence of anemia in rural adolescent girls was 54.2%, highest 63.3% was in the age group of 13 to 14yrs, 30% suffered from moderate anemia. BMI categorization showed 48.6%, 42.2%, 9% and 1.2% adolescent girls were normal, underweight, overweight and obese respectively. Underweight adolescent girls were significantly anemic (74.2%) compared to normal 48.6%, overweight 39.2% and obese 40%. Class V and IV of socioeconomic status adolescent girlswere significantly anemic 74.7% and 60% respectively when compared to Class III (42.6%), Class II (42.85%) and Class I (12%). The adolescent girls having menarche ≤13 yrs had significant anemia. Conclusion: The prevalence of anemia in rural adolescent girls was high. Under weight, class V and IV socioeconomic status and earlier age at menarche girls were at risk of developing anemia. The governments anemia prevention and control programme should focus on rural adolescent girls.


Introduction
Anemia is defined as a low level of hemoglobin in the blood and it is one of the world's most widespread nutritional problems [1]. Theprevalence of anemia among adolescents is 27% in developing countries and 6% in developed countries [2]. India has the world's highest prevalence of iron deficiency anemia among women, with 60-70% of the adolescent girls being anemic [3]. It has an impact on psychological and physical development, behavioural and work performance [4]. Association of anemiawith adverse maternal outcome such as puerperal sepsis, antepartum haemorrhage and maternal mortality is no longer a Manuscript received: 2 nd June 2016 Reviewed: 12 th June 2016 Author Corrected; 25 th June 2016 Accepted for Publication: 9 th July 2016 debatable subject [5]. Apart from the risk to the mother, it is also responsible for increased incidence of premature births, low birth weight babies and high perinatal mortality [6].
Adolescence is a period of transition between childhood and adulthood occurring between 12-18yrs of age. During adolescence anemia is more prevalent due to growth spurt, onset of menarche, poor nutrition and poverty. Anemia prevalence is usually higher in rural areas than urban areas. This stresses the need to investigate the factors associated with prevalence of anemia. Prevention of anemia is effective when the strategy is focused right from adolescence for their future reproductive life. There are very few studies focussing on anemic adolescent girls [7,8,9,10,11].
Thepresent study was designed to study the prevalence of anemia in rural school going adolescent girls and its associated factors like body mass index, socioeconomic status and age at menarche.

Materials and Methods
This prospective study was conducted in ten government schools of rural Kolhapur, among apparently healthy 1200 adolescent girls. Schools were chosen randomly and from each school 120 adolescent girls and from each Class 30 adolescent girls were selected randomly from attendance register. The girls between the age 12-16yrs were selected for the study.
The study was carried out after approval by Institutional ethical committee and permission from school principal/ headmaster. Informed consent from parents/ guardian was also taken.
Body weight was measured with light clothing and without shoes in the upright position to the nearest 100 grams, using calibrated electronic balance. Height was measured without shoes to the nearest 0.1 cm using calibrated portable stadiometer. Body mass index (BMI) was calculated by weight in kg divided by height squared in meter square. As per recommendation of Khadilkar etal [12], adolescent girls were categorised according to their BMI using BMI percentile curves for Indian girl from 5 to 18 yrs. They were Classified as: underweight (BMI <3 rd percentile), normal (BMI 3 rd percentile to adult equivalent of BMI <23), overweight (Adult equivalent of BMI 23 to adult equivalent of 27.99) and obese (adult equivalent of BMI≥28). Modified kuppuswami socio-economic status was used to divide the study groups into five Classes: Class I (upper), Class II (upper middle), Class III (lower middle), Class IV (upper lower), Class V (lower). [13] This is an important tool in hospital and community based research in India. This scale takes account of education, occupation and income of family to Classify study group in five Classes depending upon score. Taking inflation and price rise this has been modifiedwith conversion factor for the income. All adolescent girls were asked to recall their age at menarche and menstrual history were also obtained. Hemoglobin level was determined by cyanmethemoglobin method (type of colorimetric method). Blood was collected by finger prick, 20 microliter of blood sample was mixed with 5 ml of Drabkin's solution at the spot by micro pipette. Hemoglobin in the blood is converted into cyanomethhemoglobin. The absorbance of cyanomethhemoglobin was measured at 540 nm by photoelectric colorimeter on the same day of sample collection. As per WHO recommendations anaemia was diagnosed when Hb<12g/dL in 10-18 years girls [14]. The severity of anaemia was graded as mild (Hb>10g/dL), moderate (Hb7-9.9 g/dL) and severe (Hb<7g/dL). [15] All observations were recorded, tabulated and subjected to statistical analysis by Chisquaretest, in which P<0.05 was significant. The P value was determined by using the primer of biostatistics and MS Excel 2007.

Results
A total 1200 adolescent girls, from 10 schools, 120 girls from each school and 30 girls from each Classrandomly selected were included in this study. The study showed that the overall prevalence of anemia was 54.2% (1200/650) in rural school going adolescent girls. The study results emphasised the high prevalence of anemia among all age groups of adolescent girls.

Discussion
Anemia symbolizes both poor nutrition and poor health. Adolescence is a crucial phase of growth in the life cycle of an individual. In girls middle adolescence growth happens earlier (12-15yrs) than in boys (13-16yrs [21] found an association between anemia and obesity, due to upregulated hepcidin expression that hampers iron absorption. BMI is the most practical and widely used tool to ascertain an individual'sbody fat mass. A very high percentage of adolescent girls from low socioeconomic status were found to suffer from anemia in the present study. Rawat etal observed anemia was higher in socioeconomic ClassV (50%) and it significantly reduced with rise in socioeconomic status. Deshpande etal [11] and. Peter etal [18] observed similar correlation between anemia and socioeconomic class. This may be because of better availability of high quality food with rise in socioeconomic status. Bharti etal [17] did not found significant effect of socioeconomic status alone on anemia.
The commonest age at menarche in our study was 13yrs (35.2%) and there was association between earlier menarche age and risk of anemia. This could be because Normal of hormonal changes which occur at the time of onset of menarche and blood loss during menstruation. Vasanthietal [22] found that anemia was higher in postmenarcheal girls than in pre-menarchealgirls of rural area. Kakkaretal [9] observed higher the age at menarche, there are more chances of anemia. Gupta etal [10] found no association between onset of menarche and anemia in adolescent girls.
Iron deficiency anemia and anemia are often used synonymously, as iron deficiency anemia constitutes the major anemia during adolescents. This is due to rapid pubertal growth with sharp increase in lean body mass, blood volume and red cell mass which increases iron requirements for myoglobin in muscles and hemoglobin in the blood. Iron requirement increases two to three folds from a preadolescent level of 0.7 to 0.9mg iron/day to as much as 1.40-3.27mg iron / day in adolescent girls [23]. In many developing countries, one half of all children and adolescents fail to achieve their full genetic growth potential due to the combined effects of inadequate nutrition and frequent illness. Moreover due to faulty dietary habits,ignorance and in country like India with multitude of social customs and beliefs cited against women, the prevalence of anemia amongst girls remain quiet high. As per WHO, if the prevalence of anemia is equal to or greater than 40%, it can be considered a severe public health problem otherwise prevalence in the range of 20% to 39% is to be considered as moderate one. [24] More effective methods need to be devised for community based hemoglobin testing. Iron supplementation programmes need to include nutrition education programmes. Health education and nutritional advise should be given to the adolescent girls at the time of menarche.
To conclude, prevalence of anemia in rural adolescent girls was 54.2%, with highest 63.3% in the 13-14yrs age group. 30% adolescent girls were moderately anemic. Underweight adolescent girls, girls from Class V andIV socioeconomic status and girls who attained menarche at earlier age were at risk of developing anemia. The governments anemia prevention and control programme should focus on rural adolescent girls.
Contributors: SK, DK: designed the study, collected and analysed the data and drafted the manuscript. AK: supervision of the work and analysed the data. AC: literature search and drafted the manuscript. AK will act as the guarantor. All authors approved the final version of manuscript.