Thalassemia is a group of hereditary blood disorders caused by abnormal synthesis of β chains of haemoglobin Galanello and Origa (2010). β-thalassemia is an autosomal recessive disorder Hassan et al. (2016).

Approximately 1.5% of the global population (80 to 90 million people) being carriers of the disease and about 60,000 symptomatic individuals being born annually Galanello and Origa (2010). Beta-thalassemia includes three main forms: Thalassemia Major, Thalassemia Intermedia and Thalassemia Minor (also called beta-thalassemia carrier/beta-thalassemia trait). Individuals with β- thalassemia major are homozygotes for beta0 or beta+ genes characterized by two defective genes, leading to no synthesis of β-globin. These individuals have a severe form of disease requiring lifelong transfusion and may have shortened life span  Wahed and Dasgupta (2015).Individuals with Thalassemia intermedia have two defective genes, but some β-globin production is observed in these individuals, having mild anaemia, and only occasionally requiring transfusion Wahed and Dasgupta (2015). Carriers of thalassemia minor are mostly heterozygotes and are usually asymptomatic, sometimes having mild anaemia. β-Thalassemia minor is the most common form of β- thalassemia Cao and Galanello (2010). When both parents are carriers there is a 25% risk of having children with severe thalassemia Galanello and Origa (2010). Β-thalassemia is the most common single-gene disorder in the Indian population Grow et al. (2014), with over 10% of the total world thalassaemic being born in India every year Bashyam et al. (2004).India has over 35-45 million β-thalassemia carriers Colah et al. (2017). β-thalassemia is more prevalent in India than its counterpart α-thalassemia as severe alpha deletion mutations are less common in the Indian region  Panigrahi and Marwaha (2007). Certain communities in India, like Sindhis, Gujaratis, Punjabis, and Bengalis, are more commonly affected with β-thalassemia  Gupta et al. (2015). The most common mutation found in the β-globin gene is the IVS1-5(G→C) mutation (Anju Gupta et al., 2003), with a national prevalence of 56.3% in India, 64.6% in Sri Lanka and 36.5% in Pakistan  Black et al. (2010).

The aim of this study was to determine the epidemiology of Down’s syndrome and Beta- thalassemia in the Indian population. The objective of this study is to understand the prevalence of these two diseases in India which will help raise awareness about them.

 

2.    MATERIALS AND METHODS

The study was carried out by the survey-based method. A survey formulated on Google Forms was circulated through the messaging platform WhatsApp. The survey was answered by 297 adults. Majority were from the state of Maharashtra. The present study was conducted in accordance with the declaration of Helsinki. The consent was taken from all participants involved in the study.

Inclusion Criteria: In this survey, men, and women in the age group of 18 years to 90 years were included. All participants were Indians or of Indian origin. For surveying Down’s syndrome, the persons were to give the information of some family member suffering from the disease considering the physical constraints of a Down’s syndrome patient.

Exclusion Criteria: All persons below age of 18 years were excluded.

Statistical Analysis: The data obtained from the survey was analysed by online statistical software MS Excel. The tools of analysis used were Student’s t-test & Karl Pearson’s Correlation Coefficient to determine the relationship between various factors in the survey.

 

3.    RESULTS AND DISCUSSION

3.1. DOWN’S SYNDROME

Out of the 297 respondents, seven persons had a history of Down’s syndrome in their family. All the seven cases were diagnosed after birth of the child.

The gender distribution of Down’s syndrome was not skewed drastically towards any sex in general with the number of male patients being marginally higher than the number of females patients.

Figure 1  Gender Distribution of Down’s Syndrome

 

All the seven patients had complications related to Down’s syndrome such as facial abnormalities, developmental delays, and medical complications.

Figure 2 Complications associated with Down’s syndrome

 

Correlation analysis was performed to determine the relationship between the maternal and paternal ages at the time of birth of the Down’s syndrome patients. The value of Karl Pearson’s correlation coefficient obtained was 0.962087 which indicated a strong positive correlation between the two variables. Thus, higher the ages of both mother and father at the time of birth, higher was the risk of the child having Down’s syndrome.

The results of this study showed that the prevalence of Down’s syndrome is very low in India. Due to the wide diversity in demographics and ethnicity in India, there are different prevalence rates for Down’s syndrome throughout the country Al-Biltagi (2015). In a study conducted in Kozhikode district of Kerala, 66 cases out of the 274 cases studied were diagnosed with Down’s syndrome, with the mean maternal age estimated to be 30.34 years and mean paternal age to be 31.04 years, which is in contrast to the normal accepted fact that occurrence of Down’s syndrome increases with increase in maternal age Aparnna and Jose  (2014). But our study showed that there was a positive correlation between the higher maternal and paternal ages and the risk of conceiving a baby with Down’s syndrome that is consistent with the general findings from other studies  Sherman et al. (2007), Eggermann and Schwanitz (2011), Pankaj et al. (2015) Mental retardation is the most common symptom associated with this disease as indicated in our study  Verma et al. (2012).No information was obtained about the connection of Down’s syndrome to the habits of a person like smoking, alcohol consumption, contraceptive pills consumption etc, although consuming tobacco and oral contraceptives are a significant risk factor for down’s syndrome birth, with tobacco use primarily a risk factor in younger women and oral contraceptive use primarily a risk factor in older women  Ghosh et al. (2011).

 

3.2. BETA THALASSEMIA

Out of the 297 respondents, nine persons had β- Thalassemia. The gender distribution of the respondents for this disease were overwhelmingly female with only one out of the nine respondents being male.

Figure 3  Gender Distribution of β-Thalassemia

 

Of the nine respondents, six were from Maharashtra, two from Goa and one from Gujarat. The type of β-Thalassemia observed in this survey was mainly the Minor type with only two respondents having β-Thalassemia Major. No case of β-thalassemia Intermedia was reported. Five out of the nine persons had a family history of the disease.

Figure 4 Distribution of the Type of Beta Thalassemia

 

The observations of anaemia among the respondents were varied with most of them having mild anaemia. Only the two respondents with β-Thalassemia major had severe anaemia.

Figure 5 Distribution of anemia in the respondents

 

All the respondents who were β-Thalassemia minor did not take any treatment for it, while the two respondents who were β-Thalassemia major had to undergo blood transfusions every 15 days in addition to taking iron chelation tablets.

β-thalassemia is found to be moderately prevalent with the minor type of the disease accounting for majority of the cases, suggesting that β-thalassemia minor was more common in India as noticed in previous studies  Shah et al. (2017), Mohanty et al. (2013) The patients with the major type of the disease had to undergo blood transfusions as established in previous findings  Aldemir  (2018).

 

4.    CONCLUSION AND RECOMMEDATIONS

The prevalence was Down’s syndrome was found to be low in the Indian population as only 7respondents had a family history of the disease. Very less data was obtained about the disease as people may not be aware of the age of diagnosis and the age of the parents at time of birth of the affected child. The patient may not have been closely related to them. Albeit the correlation between the maternal and paternal age at the time of birth of the affected child was determined, and a positive correlation was observed. No information was obtained about the connection of Down’s syndrome to the lifestyle and habits of a person like smoking, alcohol consumption, contraceptive pills consumption etc.

β-Thalassemia was found to moderately prevalent in the Indian population with majority of the respondents having β-Thalassemia minor. There may have been more cases of the disease among the respondents as some who have the minor variant may not be aware that they have the disease. Among the respondents, anaemia was not observed as major symptom, the exceptions being the two β-Thalassemia major respondents.

The information obtained in the present survey can aid in the understanding of the occurrence and prevalence of the two diseases in India as well as increase the awareness of people for the signs and symptoms of the diseases.

 

 

 

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