Clustering of non-communicable diseases risk factors in Bangladeshi adults: An analysis of STEPS survey 2013

The current study is the third national survey on NCD risk factors in Bangladesh and the first to describe the clustering phenomena in a nationally representative survey. In addition to the high prevalence of individual risk factors, clustering of 3 or more risk factors was also found to be widely prevalent predisposing Bangladeshi people to a greater risk of NCDs.

Although Bangladeshi people consume vegetables every day, the quantity is low. This is not because vegetables are not always available; this is mostly because vegetables are not considered as nutritious food by many people. Seasonal fruit, sometimes grown in abundance, are not popular because people do not consider them as good fruit. Although popular, imported varieties remain unaffordable to many people leading to a very low consumption of fruit. Therefore a campaign is needed to popularize local fruit. A ‘5-a-day’ campaign to promote 5 servings per day can be taken as was done in England. This may be exploited to reverse the existing ‘misti’ (sweets full of simple sugar and saturated fat) culture in Bangladesh to a fruit culture. Fruit should no more be considered a sick person’s diet but it should be eaten more frequently to prevent sickness.

The global estimate for prevalence of physical inactivity among adults is 17 % [17] whereas our observed rate is more than double (38 %). Physical inactivity problem in Bangladeshi adults cannot be generalized. There are many people in Bangladesh who endure hard physical labour for their livelihood leading to a very thin body mass. In our sample, one-quarter of respondents were rather thin (BMI < 18.5 Kg/m^2). Poorly planned urbanization is the major reason for higher level of physical inactivity in urban areas. However this is now visible even in rural areas. Junk food and mechanization of life might be major contributors. Most physical activities in our sample was from work or job related. Commutation contributed to some extent but leisure time physical activity was very low. Commutation related activities could be promoted by encouraging bicycles and keeping footpaths walkable. Promotion of leisure time related activities will require engagement of non-health sectors creating recreational facilities including provision of play grounds, parks, sports, etc. An innovative strategy for uplifting physical activity of women, because they had low level of physical activity, without conflicting with social and religious norms is required.

Prevalence of both smoking (cigarette, bidi, etc.) and smokeless tobacco (zarda, gul, pan-masala, etc.) use is high in men. Although magnitude of tobacco use still remains very high, we observed lower prevalence than previous national level studies (see below for trend data). We have already reported the problem of dual use of tobacco in men [18]. Dual use exposes Bangladeshi men to an additional risk of killer NCDs [19] as has been observed in many other populations [20]. Unlike men, women hardly have any problem of dual use because smoking is extremely low in women. Women’s smoking is considered as impolite by the society. They, on the other hand, use smokeless tobacco with betel quid which is responsible for variety of diseases such as heart diseases, stroke, oral cancer, etc. Unfortunately it was not included in the Smoking Control Act [21]. Use of smokeless tobacco as a component of betel quid has a high cultural acceptance in Bangladesh. Therefore culturally appropriate public awareness will be required. Considering the public health consequences of smokeless tobacco, the amended version (2013) of the aforesaid Act has addressed smokeless tobacco adequately. Although tax measures are visible, more stringent actions are needed to curb tobacco epidemic in addition to other measures.

Overweight and obesity have been growing in Bangladesh. Prevalence of overweight in a rural population in 1998 was 6.5 % [22]. It is 10.2 % in rural area in 2010 [15] and 20.3 % in the current study. An obese baby is still considered healthier than a lean baby in Bangladesh. A fat lady is considered prettier than a thin one. Therefore public awareness campaign is to be undertaken to counter the drive to have a fat nation.

Elevated blood pressure is a recognized intermediate risk factor in developing stroke and heart attacks. One meta-analysis of population-based hypertension studies done up to 1994 reported a prevalence of 11.3 % [23]. Another meta-analysis of subsequent population studies (published from 1995 to 2009) reported a prevalence of 13.5 % [24]. In 2010 survey [15] it was 18 %; in the current study we report here a further high prevalence of hypertension (21) %. Measures to contain increasing blood pressure are seriously needed. Dietary salt must be targeted because its intake is very high (11–17 gm per day) in Bangladeshi people [25]. In spite of being a common problem and simple to identify, hypertension detection and treatment status is far from adequate in Bangladesh. Primary health care system has a good infrastructure in Bangladesh spreading all over the country. Therefore primary health care approach needs to be used to ensure adequate detection and treatment.

The distribution of risk factors was examined for rural and urban strata. As expected, all the risk factors were more prevalent in urban areas (Fig. 1). However the higher prevalence of tobacco use in urban area (although statistically non-significant) is somewhat not supportable [15]. In a few of the villages there might have been a tobacco control intervention. Therefore this difference should be interpreted with caution.

We could not measure blood glucose in this survey. About 5 % people had documented diabetes. Measurement of glucose could presumably double the prevalence because 6.8 % prevalence in a rural area has already been reported [26]. It is understandable that in urban area it will be even higher [27]. There are lines of evidences that the prevalence of diabetes is rising in Bangladesh possibly because of recent substantial changes in lifestyle. This could reflect the effect of poorly planned urbanization that lacks in environment for physical activity, and unregulated food industries promoting junk food.

We have made a brief review of the all three STEPS surveys done (2006 [28], 2010 [15] and the current one) at national level in the history of Bangladesh. Summary findings are plotted in a bar chart (Fig. 3). There is a clear indication that low intake of fruit/vegetables, sedentary behavior, overweight, hypertension and documented diabetes have been increasing. This is not surprising in a society with increasing mechanization of life paralleled to increasing availability of junk foods in absence of any specific intervention or programme. Population ageing is not the possible answer because out prevalence data are standardized for age [16]. Fortunately we have a fairly good tobacco control programme for about two decades. Therefore an opposite trend of tobacco is observable in Bangladesh.

Presence of one risk factor in turn increases the likelihood of having other risk factors showing a clustering phenomenon. Presence of hypertension may act as a pivot for clustering to happen given that the clustering was more prominent hypertensive subjects [5]. Clustering phenomenon in our sample was prominent with increasing age. Therefore detection of hypertension at an early age can be used as an entry point for preventing clustering of risk factors in Bangladeshi people.

Our study has a few important limitations. We could not measure blood glucose but collected data on self-reported/documented diabetes. This by no means provides the real prevalence estimate of diabetes. We believe this is only half of the actual case. Estimation of blood cholesterol could be more information to describe comprehensively all major risk factors of NCDs.