Making a case for community screening services: findings from a medical outreach in ibadan, Nigeria.

BACKGROUND: Currently, population based medical check up is yet to be explored as a veritable tool for assessing the burden of non-communicable diseases in Nigeria.
OBJECTIVES: This study aimed to assess the prevalence of selected lifestyle related diseases during a free medical rally in an urban community.
METHODS: General medical examinations of all participants at a free medical rally in a middle class community in Ibadan, Oyo State was conducted. Body Mass Index (BMI), blood pressure and random blood sugar measurements were done using standardised instruments. BMI classification for children was done using the CDC guidelines for males and females aged 2-20 years.
RESULTS: Of the 302 participants examined, 33.1% were males and 32.1% were less than 18 years. Of those aged 2 to 20 years, 22.9% were underweight, while 5.2% were overweight/ obese. In adults 3.6% were underweight and 43.2% were overweight/ obese. Adults were significantly more likely to be overweight/obese (P<0.001). Prevalence of high blood pressure was 29.3% and 9.4% of adults had elevated random blood glucose levels. A higher proportion of obese people (P=0.259), males (P= 0.327) and those older than 40 years (P<0.001) had elevated blood pressure. A weak correlation (spearman rho= 0.3) was found between blood pressure and BMI (P<0.001) and also between BMI and blood sugar level (spearman rho= 0.2) P=0.05.
CONCLUSION: There is a need for greater emphasis on community based screening programmes to aid early diagnosis and treatment of non communicable diseases in the country.

INTRODUCTION

Non-communicable diseases (NCD) are a major health burden in the industrialized countries, and are increasing rapidly in the developing countries owing to demographic transitions and changing lifestyles.[1] Although these lifestyle diseases have become important threats to the health of adults in sub-Saharan Africa, efforts to detect these diseases are haphazard and prevention targets are largely inexistent.[2]

Most people tend to take good health for granted. It is a known fact that almost every major ailment first manifests itself as minor symptoms, which are often not noticed and hence, neglected. As such, proper preventive health check- ups are necessary for early detection and diagnoses of these health conditions.[3] Carefully planned screening programmes are an important component of the strategy to help solve this problem. A major role of community-based projects is to demonstrate and stimulate a national NCD prevention policy. However one of the first, essential elements for a successful community intervention programme is a good understanding of the prevalent health problems.[2]

There have been arguments for and against most community based screening programmes especially about their effectiveness in detecting disease.[4] However generally the consensus is that usually by the time most NCD are clinically obvious, all therapeutic endeavours and changes in habits will, at best, produce only slight improvement in the prognosis. [3] It is therefore imperative that our efforts should be directed increasingly towards the prevention rather than the cure of the NCD processes. This can be done only by increasing public awareness of the multiple risk factors involved and, in addition, screening communities in an attempt to identify individuals who are particularly at risk. This study therefore aimed to assess the prevalence of selected lifestyle related diseases in an urban community in Ibadan

MATERIALS AND METHODS

This was a cross sectional survey conducted at Mokola, a lower class urban community in Ibadan North local government area, Oyo State. Ibadan is the capital of Oyo State, south west Nigeria. The findings obtained from the general medical examinations of all the 302 participants at a free medical rally were documented. An initial awareness campaign was conducted to sensitise the community about the medical rally. Participants included adults and children who were serially recruited as they came to the medical rally following the local publicity.

Weight, height, blood pressure and random blood sugar measurements were carried out using standardised instruments. A stadiometer was used to measure height with the respondent standing upright without shoes and against the wall, feet together and gazing forward. Height was measured to the nearest 0.5 cm. Weight was measured with a manual Seca 761 scale (Vogel & Halke, Germany) which was calibrated to zero each time weight was measured. Blood pressure for adults was measured in a sitting position using an Accoson sphygmomanometer and random blood sugar levels with Accucheck glucometer.

Hypertension was defined according to the JNC 7 criteria[5] as average blood pressure of ≥140/90 mm Hg after two readings. Body mass index (BMI) was calculated as weight (kg)/height (m2). For adults BMI was categorised thus: underweight as BMI < 18,normal weight as BMI 18-24, overweight as BMI 25-29 and obesity as BMI ≥ 30. BMI classification for children was done using the CDC guidelines for males and females aged 2-18 years. Underweight as <5th percentile, normal weight 5th percentile to less than the 85th percentile, overweight as 85th to less than the 95th percentile and obese as equal to or greater than the 95th percentile.[6] WHO diagnostic criteria (1999) was used as the cut-off for diabetes i.e. random plasma glucose > 11.1 mmol/L (200 mg/dL). Data were analyzed using SPSS version 15. Associations were explored with the Chi-square test at 5% level of significance.

RESULTS

A total of 302 participants were examined. Table shows the socio demographic characteristics of patients, females were the majority 202(66.9%) while about a third 96(31.7%) were children less than 18 years of age. The mean age of children was 8.2± 4.7 years while the mean age for adults was 46.7± 15.2.

Findings on physical examination of participants

The prevalence of hypertension was 29% while the prevalence of diabetes was 3%. The mean systolic blood pressure was 120.5 ± 19.4 mmHg, and the mean diastolic blood pressure was 74.8 ± 11.5 mmHg. Blood sugar levels ranged between 72mg/dl and 502mg/dl with a median value of 110mg/dl.

The classifications of the body mass index of the respondents are as shown in Figure . More adults were overweight and obese when compared to children however higher proportions of the children were underweight. The mean BMI for children was 16.2 ± 3.2 while for adults mean BMI was 24.9± 4.9.

Age and sex specific prevalence of hypertension among adults

As shown in Table , prevalence of hypertension among adults did not vary significantly by sex although a higher proportion of men (34.6%) had elevated blood pressure when compared to women (27.5%) (p>0.05). However a significantly higher proportion of those aged 40 and above had hypertension compared to those less than 40 years (38.1% versus 12.7% ) (p<0.05).

Age and sex specific prevalence of overweight and obesity among adults

Table The prevalence of overweight did not vary significantly by the sex of the respondents (p>0.05). However those 40years and older had a higher prevalence of overweight/obesity (P< 0.05)

Age and sex specific prevalence of diabetes among adults

Neither sex nor age of the respondent was significantly associated with the prevalence of diabetes (P.0.05) as shown in Table

Correlations

Body mass index was found to be correlated, albeit marginally with blood sugar Spearman’s rho= 0.2(P<0.05), and also with blood pressure spearman’s rho = 0.25(P=000)

DISCUSSION

This study assessed selected lifestyle related diseases in an urban community during a health fair. While some reports have demonstrated low yield during outreach programs or health fairs in community settings[4] this report has shown a relatively good yield in consonance with other reports of medical outreaches [7].

About 3 in 10 of respondents had hypertension similar to the 27.1% reported in a study in Ilorin [8] and 29% reported in Ghana [9-10]. The prevalence of hypertension increased with age and BMI this is in agreement with other studies reporting that age was correlated with blood pressure and BMI. [11]

The proportion of children overweight or obese were strikingly different from that reported for developed countries where prevalences of more than 20% have been reported [12-13] Findings are however similar to those from other studies in urban areas of Nigeria. For instance, a study in Lagos, Nigeria reported a rate of 3.7% for overweight and obesity in adolescents [14]. In this urban community underweight was more of a problem in children than overweight or obesity. Although there is a paucity of data on obesity in Nigerian children some studies have revealed heterogeneity in the nutritional problem by reporting a mixture of obesity and underweight. A study among Nigerian preschool children found a prevalence of overweight and obesity as 13.7% and 5.2% respectively while the prevalence of underweight was 8.5%.[15] Although childhood obesity is an evolving problem in Nigeria however obesity does not seem to be a major problem yet among children in this community.

Almost 20% of the adult participants in this study were obese showing a rise when compared to previous local studies [11] in which obesity prevalence was 13.2% [14].

An earlier multinational survey documented the prevalence of obesity among Nigerian adults as 8.8% in 20001. A more recent study in Jos, Nigeria however reported a higher prevalence of 21.4% for obesity in the adult population studied.[16]

In spite of the small size, this study has demonstrated that undiagnosed diabetes occurred in 3% similar to other reports[17] but much lower than the prevalence of 18.9% for undiagnosed diabetes reported in another more affluent urban population in Nigeria.[18] Literature from other countries show much higher rates of undiagnosed diabetes, as high as 56% in Saudi Arabia[19] 56% in Egypt[20] and 40% in Bahrain.[21] This prevalence was also lower than the 6.8% and 6.3% reported among adults in Nigeria and Ghana in 2000.[10] Given the increasing prevalence of obesity, it is likely that these figures provide an underestimate of future diabetes prevalence. [22]

Early diagnosis of chronic diseases is an important step toward reducing morbidity, mortality, and health care costs. Within the health care system, diagnosis of these seemingly asymptomatic diseases rests with primary care providers. This study demonstrates that population based health screening opportunities are useful.

CONCLUSIONS

This study highlights the usefulness of community screening ser vices. Programs targeting early identification of non communicable diseases should thus be encouraged. Public health practitioners are encouraged to take a stronger role in community based identification and treatment of non- communicable diseases in Nigeria.

LIMITATIONS

In a study such as we have described, biases can potentially arise from using a non random sample and also from variations in the measurements. Notwithstanding these shortcomings, and in view of the external consistency of our data with those of similar studies, these results may well be representative of the urban population of Ibadan and be reasonably used to formulate local health policy, at least for the age groups studied.

Table 1:

Socio-demographic characteristics of respondents

Variable	N(%)
Sex
Male	100(33.1)
Female	202(66.9)
Age groups
Children	97(32.1)
Adults < 40 years	71(23.5)
Adults = 40 years	134(44.4)

Table 2:

Age and sex specific prevalence of hypertension among adults

Variables	Hypertension		χ2	p value
	Present N(%)	Absent N(%)
Sex
Male	18(34.6)	34(65.4)	0.962	0.327
Female	42(27.5)	111(72.5)
Age
Less than 40	9(12.7)	62(87.3)	14.445	0.000
40 and above	51(38.1)	83(61.9)

Table 3:

Age and sex specific prevalence of overweight and obesity among adults

Variables	Overweight/obesity		χ2	pvalue
	Present N(%)	Absent N(%)
Male	6(27.3)	16(72.7)	2.194	0.139
Female	38(44.7)	47(55.3)
Age
Less than 40	12(27.3)	32(72.7)	4.063	0.044
40 and above	19(48.7)	20(51.3)

Table 4:

Age and sex specific prevalence of diabetes among adults

Variables	Diabetes		P value
	Present N(%)	Absent N(%)
Sex
Male	1(3.1)	31(96.9)	Fishers 1.0000
Female	2(2.9)	67(97.1)
Age
Less than 40	0(0)	26(100.0)	Fishers 0.567
72(96.0)	40 and above	3(4.0)