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Indian Journal of Community Medicine

Epidemiological Study of Asthma in Rural Children

Author(s): Daljit Singh, Praveen C. Sobti, Vineet Arora, R.K. Soni*

Vol. 27, No. 4 (2002-10 - 2002-12)

Deptts. of Paediatrics & SPM*, Dayanand Medical College & Hospital, Ludhiana

Abstract:

Research question: What is the prevalence of asthma in rural children?

Objective: To determine the prevalence, age distribution and epidemiological factors associated with asthma in rural children.

Study design: Prospective study.

Setting: Five villages of Dehlon block of Ludhiana.

Participants: Children between 1-15 years of age.

Statistical analysis: Fischer's Z-test.

Results: The prevalence of asthma was found to be 2.6%. Significant association was noted between family history of allergy/asthma and smoking with the prevalence of asthma.

Keywords: Asthma, Prevalence, Risk factors

Introduction:

Asthma is a common problem encountered by pediatricians and other practitioners dealing with children. Though numerous epidemiological studies have been carried out all over the world; the magnitude of the problem of asthma has not been defined with certainty. Different methodologies, population differences and different definitions of asthma have made international and even national comparisons difficult1.

The present study on rural children of Ludhiana was conducted to determine the prevalence, age distribution and epidemiological factors associated with asthma in children aged 1-15 years.

Material and Methods:

This study was carried out during the year 1999 on the pediatric population in the age group of 1-15 years residing in five villages of Dehlon block of Ludhiana which is covered under field area of Rural Health Centre Pohir, a branch of Dayanand Medical College & Hospital, Ludhiana. These villages are situated about 25 kms from industrial town of Ludhiana. The main source of income in these villages is related to agricultural practices, the majority of the population are Sikhs (89%).

The study group comprised of 2,275 children; 1,253 males and 1,022 females. The clinical and epidemiological information from the children in the study group was obtained using a questionnaire which included prevalidated criteria for diagnosis of bronchial asthma2,3. Special emphasis was laid on occupation and absenteeism from school/work, allergic symptoms like skin lesions, conjunctivitis and rhinitis. Prescription slips and other documents carried by parents were thoroughly screened for details of previous investigations done, treatment received and any hospital admission. Family history of atopy, tuberculosis, smoking and asthma was recorded. The socio-economic status of the family was determined by the Modified Udai Pareek Scale (MUP) for rural area4 and graded as under:

  • Low <15
  • Middle 16-28
  • High >28

Variables like number of pets in the house, overcrowding and cooking fuel used were noted. Overcrowding was expressed by number of persons per room5.

Asthma was diagnosed based on clinical symptomatology using modified American Thoracic Society (ATS) criteria. Presence of at least three of the following symptoms in the past twelve months was taken as bronchial asthma; (a) persistent cough (cough lasting for more than three weeks), (b) wheeze with cold, (c) wheeze apart from cold and (d) dysponea with wheeze.

500 children in the study population were chosen as control group by fixed random distribution. Variables associated with chronic/recurrent cough were noted in the control group for comparison with the positive cases.

Results:

A total of 2,275 children between 1-15 years were screened for bronchial asthma. There were 1,253 boys and 1,022 girls with male female ratio of 1.2:1.

Table I: Age and sex distribution of cases.

Age group (yrs) Male Female Total %
1-5 8 5 13 (22.4)
5-10 18 15 33 (56.9)
10-15 8 4 12 (20.7)
Total 34 24 58  

Figures in parentheses indicate percentages

Out of 2,275 children in the study group, 58(34 males and 24 females) were diagnosed as having bronchial asthma, giving a prevalence rate of 2.6%. (Table I)

Table II: Association with family history of allergy/asthma, smoking and environmental factors.

Factors* Cases
(n=58)
Controls
(n=500)
Z p
Family history of allergy/asthma 22 (37.9) 52 (10.4) 5.85 <0.01
Family history of smoking 8 (13.8) 32 (6.4) 2.07 <0.05
Overcrowding 32 (55.2) 225 (45) 1.47 NS
Pets in household 8 (13.8) 45 (9.0) 1.18 NS
Smoke producing cooking fuel 40 (69.0) 310 (62.0) 1.04 NS

Figures in parentheses indicate percentages; NS - non-significant, *Multiple responses.

Family history of allergy/asthma was noted in 22(37.9%) children with asthma as compared to 52(10.4%) in the control group. This difference was statistically significant (p<0.01). Family history of smoking was recorded in 13.8% of cases as compared to 6.4% in the controls. This difference was also statistically significant (p<0.05) (Table II).

Overcrowding was noted in 55.2% of the cases as compared to 45% in the control group (p>0.05). Pets were found in 8 houses (13.8%) among cases of asthma in contrast to 9% in control group (p>0.05). Smoke producing fuels (wood, cowdung, kerosene, etc.) were used by 40(69%) of families among children with asthma in comparison to 310(62%) in the control group (p>0.05).*

Table III: Association with socio-economic status.

Socio-economic
status
Cases
(n=58)
Controls
(n=500)
Z p
Low 4 (6.9) 52 (10.4) 0.84 NS
Middle 45 (77.6) 342 (68.4) 1.44 NS
High 9 (15.5) 106 (21.2) 1.01 NS

Out of 58 cases, maximum number i.e. 45(77.6%) belonged to middle socio-economic class. This distribution of children with asthma was not statistically different in comparison to the distribution in the control group (p>0.05)(TableIII). School absenteeism was observed in 65% patients with asthma. Mean loss of school days over one year was 16.5+8.45 days.

Discussion:

The current prevalence of asthma in our study was found to be 2.6%. This is consistent with prevalence rates of asthma (0.2-6.3%) reported from developing countries6-13. There is paucity of data on the prevalence of bronchial asthma in children in India. In a study carried out in Patna in 1966, Vishwanathan R et al reported a prevalence of 0.2% in children below nine years6. In a recent study carried out in Delhi school children in the age group of 5-16 years, Chhabra SK et al documented a current prevalence of 11.9%14. The higher prevalence in their study could be due to allergens or urban environmental pollution precipitating development of asthma in susceptible children.

The male to female ratio in our study was found to be 1.4:1. This is in accordance with the previous studies which also depicted male preponderance ranging from 1.4:1 in the United States15 to over 2:1 from New Zealand16. Chhabra SK et al reported a male: female ratio of 1.2:1 among children in the age group of 5 to 16 years14. The male predominance may be related to a greater degree of bronchial lability in males17.

Family history of allergy/asthma was significantly higher in the asthma group (37.9%) as compared with the control group (10.4%). This association between family history of allergy/asthma and occurrence of asthma has also been documented in various other studies. Vishwanathan R et al observed a family history of asthma in 42% of asthmatic subjects but in only 10% of non-asthmatics6. Sibbald B et al reported a prevalence of 13% in first degree relatives of asthmatics but only 4% in those of non-asthmatics18. Gerrard JW et al found significant association between asthma, hay fever and recurrent rhinitis in parents and children19. Lebowitz MD et al also demonstrated a strong familial concordance of prevalence of asthma in families after controlling for other factors20.

Ninan TK et al observed parental history of asthma in 42% patients with polysymptomatic asthma as compared to 13% in asymptomatic children (p<0.001)21. Chhabra SK et al reported a strong association between family history of atopic disorders and the prevalence of asthma14.

In the present study, significant association was also found between family history of smoking and asthma (p<0.05). Weiss ST et al also reported a linear relationship between parental smoking and persistent wheezing in children22. Ninan TK et al found a significant association (p<0.05) between parental history of smiling and asthma21. Chhabra SK et al noted a risk for the occurrence of current asthma in children having smokers in the family of 1.6 times more than in children not having smokers in the family14. Faniran AO et al made similar observations23.

The present study showed no significant association of asthma with overcrowding, pets and cooking fuel used. These observations are in accordance with the previous studies on asthma. Gergen Peter J et al noted no significant association between crowding and asthma15. Clifford RD et al found no significant association between pets and wheezing24. Both Schenker MB et al and Chhabra SK et al found no significant association between the prevalence of wheeze and asthma with the type of domestic fuel used in kitchen14,25. However, Bener A et al observed increased prevalence rate of asthma in children belonging to families owning pets26.

Majority of children with asthma belonged to middle socio-economic class (according to MUP score). This distribution was in conformity with that in the control population. A consistent association has not been noted between asthma and social class14,24,27.

Epidemiology of asthma is a growing area of research. There are still several aspects of asthma which need to be studied in depth. Epidemiology remains a vital tool in the study of causation of asthma.

References:

  1. Chhabra SK. Epidemiology of childhood asthma. Indian Journal of Chest Diseases and Allied Sciences 1998; 40: 179-93.
  2. Forastiere F, Corbo GM, Michelozzi P, Pistelli R, Agabiti N, Brancato G, Ciappi G, Perucci CA. Effects of environment and passive smoking on the respiratory health of children. Int J Epidemiol 1992; 21(1): 66-73.
  3. Samet JM. Epidemiologic approaches for the identification of asthma. Chest 1987; 91 (Suppl 6): 74S-8S.
  4. Pareek U, Trivedi G. Manual of socio-economic status scale (rural). New Delhi, Manasayan Publishers, 1995.
  5. Park R. Environment and health. In: Park's Textbook of Preventive and Social Medicine, 15th edn. Eds. Park K. Jabalpur, M/s. Banarsidas Bhanot, 1997; 507.
  6. Vishwanathan R, Prasad M, Thakur AK et al. Epidemiology of asthma in an urban population: A random morbidity survey. J Indian Med Assoc 1966; 46: 480-3.
  7. Ozkaragoz K, Cakin F. Atopic children in Turkey. Ann Allergy 1969; 27: 13-7.
  8. Pearson RSB. Asthma in Barbados. Clin Allergy 1973; 3: 289-97.
  9. Asch AJ, Rabin DL, Hurwitz A, Medalie JM. Bronchial asthma in an Israeli community. Israel J Med Sci 1973; 9: 104-21.
  10. Bangham CRM, Hope RA. Exercise induced asthma in Nepalese children. Clin Allergy 1981; 11: 273-80.
  11. Woolcock AJ, Konthen PG, Sedgwick C. Bronchial reactivity of school children in an Indonesian village. Bull IUAT 1982; 57: 266-73.
  12. Woolcock AJ, Dowse GK, Temple K, Stanley H, Alpers MP, Turner KJ. The prevalence of asthma in the South-Fore people of Papua New Guinea: A method for field studies of bronchial hyperreactivity. Eur J Respir Dis 1983; 64: 571-81.
  13. Hseih KH, Shen JJ. Prevalence of childhood asthma in Taipei, Taiwan and other Asian Pacific countries. J Asthma 1988; 25: 73-82.
  14. Chhabra SK, Gupta CK, Rajpal S, Chhabra P. Prevalence of asthma in school children in Delhi. J Asthma 1998; 35: 291-6.
  15. Gergen PJ, Mullally DI, Evans R. National survey of prevalence of asthma among children in the United States, 1976 to 1980. Pediatrics 1988; 81(1): 1-17.
  16. Milne GA. The incidence of asthma in Lower Hutt. NZ Med J 1969; 70: 27-9.
  17. Verity CM, Van HB, Carswell F, Hughes AO. Bronchial liability and skin reactivity in siblings of asthmatic children. Arch Dis Child 1984; 59: 871-6.
  18. Sibbald B, Horn MEC, Brain Ea, Gregg I. Genetic factors in childhood asthma. Throax 1980; 35: 671-4.
  19. Gerrad JW, Ko CG, Vickers P, Gerrad CG. The familial incidence of allergic disease. Ann Allergy 1976; 36: 10-5.
  20. Lebowitz MD, Barbee R, Burrows B. Family concordance of IgE, atopy and disease. J Allergy Clin Immunol 1984; 73: 259-64.
  21. Ninan TK, Macdonald L, Russel G. Persistent nocturnal cough in childhood: a population based study. Arch Dis Child 1995; 73: 40-7.
  22. Weiss ST, Tager IB, Speizer FE, Rosner B. Persistent wheeze: Its relation to respiratory illness, cigarette smoking and level of pulmonary function in a population sample of children. Am Rev Respir Dis 1980; 122: 697-707.
  23. Faniran AO, Peat JK, Woolcock AJ. Persistent cough: is it asthma? Arch Dis Child 1988; 79: 411-14.
  24. Clifford RD, Radford M, Howell JB, Holgate ST. Prevalence of respiratory symptoms among 7 and 11 year old school children and association with asthma. Arch Dis Childhood 1989; 64: 1118-25.
  25. Schenker MB, Samet JM, Seizer FE. Risk factors for childhood respiratory disease. The effect of host factors and home environment exposures. Am Rev Respir Dis 1983; 128: 1038-43.
  26. Bener A, al-Jawadi TQ, Ozkaragoz F, al-Frayh A, Gomes J. Bronchial asthma and wheez in a desert country. Indian J of Pediatrics 1993; 60(6): 791-7.
  27. Mitchell EA, Stewart AW, Pattermore PK, Asher MI, Harrison AC, Rea HH. Socio-economic status in childhood asthma. Int J Epidemiol 1989; 18: 888-90.
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