Annals of African Medicine
Home About AAM Editorial board Ahead of print Current Issue Archives Instructions Subscribe Contact us Search Login 


 
SHORT REPORT
Year : 2009  |  Volume : 8  |  Issue : 3  |  Page : 177-180 Table of Contents     

Prevalence of irritable bowel syndrome: A community survey in an African population


1 Department of Medicine, Faculty of Medical Sciences, University of Jos, Plateau State, Nigeria
2 Department of Community Medicine, Faculty of Medical Sciences, University of Jos, Nigeria

Date of Web Publication26-Oct-2009

Correspondence Address:
Edith N Okeke
Department of Medicine, Jos University Teaching Hospital, PMB 2076, Jos, Plateau State
Nigeria
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1596-3519.57241

Rights and Permissions
   Abstract 

Background : Irritable bowel syndrome (IBS) has been reported to be common in the West. Community surveys are lacking in the African setting. We determined the prevalence of IBS in a rural community setting in Nigeria.
Method : Questionnaires were administered to consenting individuals. Subjects satisfying the Rome II criteria for IBS were invited for physical examination at a health center to identify the presence of "alarm factors."
Results : One hundred forty (31.6%) of the 443 evaluated individuals fulfilled the Rome II criteria for IBS, with a male-to-female ratio of 1.37:1 (P= .11). The prevalence of IBS was highest (39.3%) in the third decade, followed by 25% in the fourth decade (P= .009). Ninety-six (67%) IBS individuals had the alternating pattern of diarrhea and constipation, whereas 28 (20%) and 19 (13%) had constipation and diarrhea subtypes, respectively.
Conclusion : IBS as diagnosed by the Rome II criteria has a high prevalence in the African rural population, as obtained elsewhere.

   Abstract in French 

Contexte : Irritable Syndrome (IBS) a été signalé à être commune à l'Ouest. Enquêtes communautaires font défaut dans le contexte africain. Nous avons déterminé la prévalence de IBS dans un milieu rural. communauté définition dans le Nigéria.
Méthode : Questionnaires ont été administré aux personnes consentantes. Sujets de satisfaction de la Rome II critères d'IBS ont été invités pour l'examen physique dans un centre de santé à identifier la présence de " alarme les facteurs ".
Résultats : Un cent et quarante (31,6 %) des individus évaluées 443 rempli le Rome Critères II IBS avec un mâle à ratio féminin de 1.37:1 (p = 0,11) .la prévalence IBS était plus élevé dans la troisième décennie (39.3 %), suivie de 25 % dans le quatrième dix ans (p = 0.009). Quatre-vingt-seize (67 %) IBS personnes avaient le modèle d'alternance de la diarrhée et constipation, alors que 28 (20 %) et 19 (13 %) avaient constipation et la diarrhée subtypes respectivement.
Conclusion : IBS comme un diagnostic par les critères de Rome II a une haute prévalence dans la population rurale africaine comme obtenu ailleurs.

Keywords: Africans, Community, Irritable Bowel Syndrome


How to cite this article:
Okeke EN, Ladep NG, Adah S, Bupwatda PW, Agaba EI, Malu AO. Prevalence of irritable bowel syndrome: A community survey in an African population. Ann Afr Med 2009;8:177-80

How to cite this URL:
Okeke EN, Ladep NG, Adah S, Bupwatda PW, Agaba EI, Malu AO. Prevalence of irritable bowel syndrome: A community survey in an African population. Ann Afr Med [serial online] 2009 [cited 2019 Aug 18];8:177-80. Available from: http://www.annalsafrmed.org/text.asp?2009/8/3/177/57241


   Introduction Top


Irritable bowel syndrome (IBS) is an indolent nonprogressive bowel disorder. It has significant morbidity resulting in absenteeism at work and school and a reduced quality of life. It is a chronic disorder of unknown etiology clinically consisting of altered bowel habits, abdominal pain and the absence of any detectable organic pathologic process. It is a disorder of young people between ages 20 and 50 years. [1] The age of onset varies but is unusual after the age of 50. [2] The incidence appears to increase during adolescence and peaks in the third and fourth decades of life. [2]

IBS has been extensively studied in the western world. It has been shown that 15% of adults in the United States of America and a similar number in Europe report symptoms consistent with the diagnosis of IBS, while the figures for Asia and Africa are much lower. [1],[3] Eight percent of patients attending a clinic in Kenya and 33% of individuals seeking care in primary care settings in Nigeria were found to have IBS. [4],[5] A report from western Nigeria showed 30% prevalence in a select population of students. [5] Recently, we reported a prevalence of 26.1% in a similar youthful population. [6]

Generally, studies from Africa are hospital based [3],[4],[5],[6] and may not reflect the true prevalence of the disease. We describe the prevalence and characteristics of IBS in a rural community in Nigeria.


   Methods Top


Study population

The study population consisted of consecutive willing individuals from Gindiri, a rural community located in Plateau State, Nigeria. They were individuals aged 15 to 50 years.

Study area

Gindiri is a district in Mangu Local Government Area of Plateau State. It has a population of 40,400 (2006 National Population Census Survey). It is mainly populated by peasants and farmers . It has several dispensaries and a Comprehensive Health Center that is supervised by the Community Health Department of the Jos University Teaching Hospital.

Ethical consideration

The ethics committee of the Jos University Teaching Hospital approved the study. Verbal informed consent was obtained from the subjects.

Study design

This was a descriptive study. Subjects were randomly selected for this study. A house-to-house visit was embarked upon, and individuals aged 15 to 50 years were offered the right to participate in the study. Subjects were interviewed using a standard questionnaire, as reported previously. [6],[7] Subjects satisfying the Rome II criteria [8] for IBS were then invited to the Comprehensive Health Center for physical examination to identify the presence of "alarm factors." Microscopy of stools was carried out on all subjects for ova and cysts of intestinal parasites. Excluded from the study were pregnant women and subjects with "alarm factors."

Statistical analysis

The minimum sample size was determined based on the prevalence reported in the literature, using the following formula:

N= (Zi-α) 2 (P)(1-P)

d 2

where

N= minimum sample size,

P= best estimate of prevalence of IBS from the literature review expressed as a fraction of 100 (in this case, 30%= 0.3), [5]

Zi-a= a constant at 95% confidence interval for a two-tailed descriptive study (=1.96),

d= absolute precision, i.e., value required (in percentage points) which in actual terms describes the maximum difference between the population rate and the sample rate that can be tolerated. Five percent (0.05) is adapted for this study.

Thus, N= 1.96 2 (0.3)(0.7) = 323 (0.05) 2

Consequently, 460 subjects were recruited for this study to improve the power of the study.

Data was analyzed using the Epi Info 2004 statistical program.

Means and standard deviations were used to describe continuous variables and proportions for categorical data. Two-tailed Student t test was used for comparison of means, while the significance of observed differences (proportions) was determined using chi-square test.

A P value of < 0.05 was considered statistically significant.


   Results Top


Of the 460 subjects recruited, 17 were excluded (2 had incomplete records, 5 had blood in their stools, and 10 had parasitic infestations). Thus, 443 subjects (52.6% females and 47.4% males) were analyzed. The mean age of the population was 32.3± 10.9 years (range, 15-50 years), with mean age of the females being 33.4± 11.1 years and the mean age of males being 31.1± 10.7 years (t= 2.25; P= 0.02).

Prevalence of IBS

One hundred forty (31.6%) out of the 443 evaluated individuals fulfilled the Rome II criteria for IBS. Of the 140 IBS patients, 47.1% were females and 52.9% were males. The prevalence of IBS was highest in the third decade [Table 1], being 39.3%, followed by that in the fourth decade, being 25% (χ2 = 11.50; P= 0.009).

IBS subtypes

Ninety six (67%) IBS individuals had, characteristically, the alternating pattern of bowel habit, comprising diarrhea and constipation; whereas 28 (20%) and 19 (13%) had constipation and diarrhea subtypes, respectively.


   Discussion Top


The prevalence of IBS in this community survey was 31.6%. This is higher than the rates of 10%-20% reported from Western communities [9],[10],[11] and 4% in Singapore. [12] There have been no community surveys in Africa to compare our results with. This rate is however comparable to the 30% prevalence reported by a previous study in western Nigeria, [4] as well as an earlier report of 26.1% [6] in Jos, Nigeria, although these studies were in a subset of the population. We had demonstrated a similar prevalence of 33% among patients seeking health care at primary health facilities within Jos, Nigeria. [13] This suggests that IBS is about as prevalent in health care seekers as in non-health care seekers in Nigeria. Previous workers have shown that the rates of IBS are higher among patient populations relative to community samples. [14] This finding shows that IBS is not rare among native Africans.

The prevalence of IBS was highest among subjects in their third decade of life when compared with subjects of other age groups. This is in agreement with the natural history of IBS, which has shown that the incidence of the disorder rises around adolescence and peaks in the third and fourth decades of life. [1],[2] However, other studies of the epidemiology of the disease in Bangladesh, [15] Croatia [16] and Turkey [17] did not find any significant relationship between age and IBS. Generally, IBS is a disease of young adults. Subjects presenting with IBS-like symptoms in the older age have high chances of organic disease and should have colonoscopy performed.

Gender had no significant relationship to IBS in this study. This is similar to the finding in Iran by Hoseini and others. [18] Studies in the western world and a similar study in the southern part of Nigeria show a female preponderance of IBS. [19],[20] In contrast, Indian and Kenyan investigators [5] reported male preponderance. Our finding in this study agrees with our previous findings among a student population in Nigeria. [6] These differences may be due to differing characteristics of the subjects; and the diagnostic criteria, as some of the studies used the Manning criteria. [6]

Our study was not without limitations. The Rome criterion has not been validated in the African population even though it is widely used in clinical practice within the region. We attempted improving the accuracy of the diagnosis of IBS in this population by conducting stool microscopy, but it did not eventually change significantly the results with regard to prevalence when compared to those in previous reports from Nigeria.

In conclusion, IBS diagnosed by the Rome II criteria is quite common among our population. Clinicians need to be aware of this so as to help reduce the burden on already overstretched health facilities as well as manage the sufferers appropriately.


   Acknowledgment Top


This research was supported by the Faculty Research Grant of the Faculty of Medical Sciences, University of Jos; no. FRG/FMS/05/06/006.

 
   References Top

1.Hasler WL, Owyang C. Irritable bowel syndrome. In: Yamada T, Alpers DH, Owyang C, Powell DW, Silverstein FE. Textbook of Gastroenterology. Philadelphia: J.B. Lippincott Company; 1991. p. 1696-714.   Back to cited text no. 1      
2.Mertz HR. Irritable bowel syndrome. N Engl J Med 2003;349:2136-46.  Back to cited text no. 2      
3.Dunphy RC. New therapies for irritable bowel syndrome. Res Rep 2000;5:15-22.  Back to cited text no. 3      
4.Olubuyide IO, Olawuyi F, Fasanmade AA. A study of Irritable Bowel Syndrome diagnosed by Manning criteria in an African population. Dig Dis Sci 1995;40:983-5.  Back to cited text no. 4      
5.Lule GN, Amayo EO. Irritable bowel syndrome in Kenyans. East Afr Med J 2002;79:360-3.  Back to cited text no. 5      
6.Okeke EN, Agaba EI, Gwamzhi L, Achinge GI, Angbazo D, Malu AO. Prevalence of Irritable Bowel Syndrome among a Nigerian Student Population. Afr J Med med Sci 2005;34:33-6.  Back to cited text no. 6      
7.Ladep NG, Obindo TJ, Audu MD, Okeke EN, Malu AO. Depression in patients with irritable bowel syndrome in Jos, Nigeria. WJG 2006;48:7844-7.  Back to cited text no. 7      
8.Thompson WG, Longstreth G, Drossman DA. Functional bowel disorders and functional abdominal pain. Gut 1999;45:1143-7.  Back to cited text no. 8      
9.Agrιus L, Svδrdsudd K, Nyrιn O, Tibblin G. The epidemiology of abdominal symptoms: Prevalence and demographic characteristics in a Swedish adult population. Scand J Gastroenterol 1994;29:102-9.  Back to cited text no. 9      
10.Gary G. Irritable bowel syndrome. In: Critical issues in Gastronterology. In: Tony L, Lin, Emeran AM, editors. Philadelphia: Williams and Wilkins; 1999. p. 54-72.   Back to cited text no. 10      
11.Talley NJ, Zinsmeister AR, Melton LJ. Prevalence of irritable bowel syndrome in a community: Symptom subgroups, risk factors and health care utilization. Am J Epidemiol 1995;142:76-83.  Back to cited text no. 11      
12.Camilleri M, Muller-Lisner SA. World Prevalence of irritable bowel syndrome. In: Irritable bowel syndrome: Taking concepts into clinical practice symposium held at the Palace Hotel in San Francisco, Carlifornia. [last accessed on 2002 Aug 15].  Back to cited text no. 12      
13.Ladep NG, Okeke EN, Samaila AA, Agaba EI, Ugoya SO, Puepet FH, et al. Irritable Bowel Syndrome among patients attending General Outpatients' clinics in Jos, Nigeria. Eur J Gastroenterol Hepatol 2007;19:795-9.  Back to cited text no. 13      
14.Whitehead WE, Bosmajian L, Zonderman A. Symptoms of psychologic distress associated with irritable bowel syndrome. A comparison of community and medical samples. Gastroenterology 1988;95:709-14.  Back to cited text no. 14      
15.Masud MA, Hasan M, Khan AK. Irritable Bowel Syndrome in a rural community in Bangladesh: Prevalence, symptoms pattern and health care seeking behaviour. Am J Gastroenterol 2001;96:1547-52.  Back to cited text no. 15      
16.Baretic M, Bilic A, Jurcic D, Mihanoviζ M, Suniζ-Omejc M, Dorosuliζ Z, et al. Epidemiology of Irritable Bowel Syndrome in Croatia. Coll Antropol 2002;26:85-91.  Back to cited text no. 16      
17.Karaman N, Turkay C, Yonem O. Irritable Bowel Syndrome prevalence in the city center of Sivas. Turk J Gastroenterol 2003;14:128-31.  Back to cited text no. 17      
18.Hoseini-Asl MK, Amra B. Prevalence of Irritable Bowel Syndrome in Shahrekord, Iran. Indian J Gastroenterol 2003;22:215-6.  Back to cited text no. 18      
19.Talley NJ, O'Keefe EA, Zinsmeister AR, Melton LJ. Prevalence of gastrointestinal symptoms in the elderly: A population-based study. Gastroenterology 1992;102:895-901.  Back to cited text no. 19      
20.Mitchel CM, Drossman DA. Survey of the American Gastroenterological Association membership relating to patients with functional gastrointestinal disorders. Gastroenterology 1987;92:1282-4.  Back to cited text no. 20      



 
 
    Tables

  [Table 1]


This article has been cited by
1 Global Prevalence of and Risk Factors for Irritable Bowel Syndrome: A Meta-analysis
Lovell, R.M. and Ford, A.C.
Clinical Gastroenterology and Hepatology. 2012; 10(7): 712-721
[Pubmed]
2 A global perspective on irritable bowel syndrome: A consensus statement of the world gastroenterology organisation summit task force on irritable bowel syndrome
Quigley, E.M.M. and Abdel-Hamid, H. and Barbara, G. and Bhatia, S.J. and Boeckxstaens, G. and De Giorgio, R. and Delvaux, M. and Drossman, D.A. and Foxx-Orenstein, A.E. and Guarner, F. and Gwee, K.-A. and Harris, L.A. and Hungin, A.P.S. and Hunt, R.H. and Kellow, J.E. and Khalif, I.L. and Kruis, W. and Lindberg, G. and Olano, C. and Moraes-Filho, J.P. and Schiller, L.R. and Schmulson, M. and Simrén, M. and Tzeuton, C.
Journal of Clinical Gastroenterology. 2012; 46(5): 356-366
[Pubmed]
3 Prevalence of irritable bowel syndrome and its relation to lifestyle and depression quotient in a japanese general population
Kumeta, K. and Danjo, K. and Matsuzaka, M. and Takahashi, I. and Watanabe, K. and Iwane, K. and Tsuya, R. and Umeda, T. and Sato, K. and Fukuda, S. and Nakaji, S.
Hirosaki Medical Journal. 2011; 62(2-4): 144-165
[Pubmed]



 

Top
 
  Search
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

 
  In this article
    Abstract
    Introduction
    Methods
    Results
    Discussion
    Acknowledgment
    References
    Article Tables

 Article Access Statistics
    Viewed2321    
    Printed140    
    Emailed1    
    PDF Downloaded142    
    Comments [Add]    
    Cited by others 3    

Recommend this journal