Identification of Socioeconomic Variables Responsible for Obesity Kidney Disease among Bangladeshi Adults

The information presented here were the analytical results observed from data collected in investigating 995 Bangladeshi adults of 18 years and above. The objective of the investigation was to identify socioeconomic variables which enhance the health hazard obesity kidney disease. The analysis indicated that this health problem was noted among 6.2% respondents and it was predominant among males, non-Muslims, elderly people, lower level educated adults, people belonged to families of medium economy, smokers, adults involved in sedentary activities, diabetic and hypertensive respondents. The prevalence rates among these respondents were 0.074, 0.088, 0.188, 0.099, 0.098, 0.088, 0.075, 0.075 and 0.186, respectively. However, all these socioeconomic variables were not similarly responsible for obesity kidney disease among the adults. The most responsible variable was family expenditure followed by family income, physical labour, age, process food consumption, hypertension and duration of diabetes. These variables were identified by factor analysis.


Introduction
Obesity, like hypertension and diabetes, is the major risk factor in developing kidney disease among human beings, especially among elderly people [1, 2, 3, 4, 5, and 6]. It increases the risk of chronic kidney disease (CKD) and end stage of renal disease (ESRD). It was noted that the elevated body mass index rapidly enhanced the CKD among the preexisting CKD patients and even among healthy men [2,4]. The adverse impact of obesity on the kidney creates other complications, like nephrolithiasis and kidney malignancies. This is true for both men and women.
One of the cause of kidney failure is diabetes which is a condition characterized by high blood glucose levels and if this condition exists for long time it damages the millions of tiny filtering units within each kidney resulting kidney failure [7,8]. It indicates that poor glucose control is a risk factor for kidney function alteration both in type-1 and type-2 diabetes [7]. Thus, it can also be said that the risk of kidney disease is associated with obesity, pre-diabetes and hypertension [8, 9, 10, and 11]. The prevalence of obesity was increasing in many countries, especially in developing countries due to socio-demographic upward mobility despite continuing nutritional deficiencies [12,13]. In developed countries the problem of obesity has been increasing rapidly [12, 14, 15, and 16]. In 2016, the reported overweight adults of age 18 years and above were 1.9 billon and obese adults were 650 million [17].
The burden of obesity was shifting towards lower socioeconomic group of people most of whom are living in Asia-pacific region. Bangladesh is an Asian country and it has every chance of facing the problem of obesity and its consequences. Thus, it needs to study the proportion of obese people in Bangladesh and the proportion of obese kidney disease patients in the country. The specific objective of the present study is to identify the responsible socioeconomic variables for the prevalence of obesity and kidney disease simultaneously among the adults people of Bangladesh.

Methodology
The data for this research were collected by some nurses and medical assistants working in diagnostic centres. The centres were purposively selected from both urban and semi-urban areas of Bangladesh. The respondents of this study were 498 males and 497 females of age 18 years and above totalling 995 adults. This composition of male and female was considered to cover the national sex ratio 50.1: 49.9 of population of Bangladesh [18]. The investigated units were the residents of both urban and rural localities. As the adults were investigated from diagnostic centre, most (67%) of them were found diabetic patients. The data were recorded during the session 2018-19.
The information of different socioeconomic variables of each selected respondent were recorded through a pre-designed and pre-tested questionnaire containing different questions related to residence, religion, gender, marital status, age, education, occupation, family income, family expenditure. Beside these demographic data, other information were on life-style, and prevalence of any of the noncommunicable diseases, duration of diabetes, and the stages of treatment of the disease including cost of treatment. Some of the socioeconomic variables were qualitative and some were quantitative in nature, but all the variables were noted in nominal scale for ease of analysis. The data of weight (in kg) divided by height (in metre 2 ) was used to measure the value of body mass index (BMI) to identify obese adults (if BMI ≥ 27.5; underweight, if BMI< 18.5; normal, if 18.5 ≤BMI< 23.0; overweight, if 23.0 <BMI< 27.5) [19,20]. They were also divided into 4 groups according to their blood pressure (B.P) level (mmHg). The 4 groups were identified as optimal (if BP < 120/80), normal (if BP <130/85), high normal (if BP < 140/90) and hypertensive (if BP ≥ 140/90) [21,22].
To fulfil the objective of the study, the association of each of the socioeconomic variable with simultaneous prevalence of obesity kidney disease was investigated, where significant association was decided if pvalue of any Chi-square statistic ≤ 0.05 [P ( 2  ) ≤0.05]. Irrespective of significant or insignificant association, the risk ratio and its confidence interval was calculated for adults for whom prevalence of obesity kidney problem was noted in higher rate for a particular level of a socioeconomic variable. Finally, factor analysis was done to select the most responsible factor for the prevalence of this health hazard. The most responsible factor was identified depending on the highest absolute value of factor loadings observed in doing factor analysis [23, 24, and 25]. All the calculations were done using SPSS Version 25.

Results
Total respondents were 995, they were classified by level of obesity and prevalence of different health problem. Classified adults were shown in Table 1 below: Among the respondents 30.2% were obese, 12.4% had kidney problem and prevalence of obesity kidney disease was noted in 6.2% respondents. The percentage of obese adults suffering from kidney problem was 20.7. The percentages of adults of different health problems were in significantly increasing trend with the increase in level of body

Factor Analysis
The study of association of prevalence of obesity kidney disease with socioeconomic variable showed that age, smoking habit, sedentary activity, prevalence of diabetes, duration of diabetes and blood pressure level were significantly influencing factors. But none of these variables could be identified as most responsible one for the prevalence. To identify the most responsible variable factor analysis was done utilizing all the studied variables. But final factor analysis was done using the variables which showed at least 0.50 as communality during analysis. The final included variables were age, family income, family expenditure, habit of consumption of process food, physical work, duration of diabetes and blood pressure level. These included variables were satisfactory as KMO = 0.705 which gave 2  =22.710 with p -value=0.000. The variables explained 72. 353% variation in the data set. The analysis showed that family expenditure was the most responsible variable for the prevalence of obesity kidney disease followed by family income, physical work, and age, consumption of process food, blood pressure level and duration of diabetes. The results of factor analysis were shown in Table 3.  Table 3: Results of factor analysis

Discussion
Overweight and obesity are associated with chronic kidney disease [26, 27, and 28]. This phenomenon is observed even among non-diabetic patients [29]. Besides overweight and obesity, other related variables are lifestyle factors such as smoking habit, physical activity, fast food consumption, diet quality, and diabetes, hypertension [7, 30, and 31]. The other socioeconomic variables are also expected to be associated with CKD as these are associated with obesity [32]. The socioeconomic variables may have impacts on simultaneous prevalence of obesity kidney disease. This hypothesis lead to identify some of the responsible socioeconomic variables for prevalence of this health hazard. For this, investigation was conducted on 995 adults of 18 years and above residing in both urban and rural areas of Bangladesh.
From the analysis of the data it was observed that obesity kidney disease was prevailed among 6.2% adults. Some of the socioeconomic variables were significantly associated with prevalence of the disease. These are age, smoking habit, prevalence of diabetes, duration of diabetes and blood pressure. The prevalence rate was 16.9% among elderly people of age 50 years and above (19.6%). The risk of the disease was more than 4 times for this group of adults. The prevalence rate was 8.8% among smokers (33.1%). The chance of prevalence was 89% more compared to that of non-smokers. Among diabetic adults (67%) the prevalence rate was 7.5% and they were two times exposed to this health hazard compared to nondiabetic adults. The percentage of adults suffering from diabetes for 15 years and above was 4.4. For them the risk of prevalence was more than 3 times as it was for others. Percentage of hypertensive adults was 5.9 and prevalence rate was 18.6% in them. Their risk of prevalence was 3.42 times as it was in others.
Religion was independent of prevalence of obesity kidney disease but non-Muslims (14.8%) were 60% more exposed to this health hazard. Family income and family expenditure were not significantly associated with this health problem, but adults (6.1%) belonged to medium income (Taka 100 -150 thousand per month) had 64% more risk of prevalence. The chance of prevalence of the disease was 74% more for adults (14.4%) belonged to families spending 60 -80 thousand taka. The percentage of adults involved in sedentary activity was 44.4 and they were more exposed to this health problem by 54%. The risk of prevalence of obesity kidney disease was almost similar for adults irrespective of gender, residence, marital stats, physical work, and process food consumption.
Some variables were found significantly associated with prevalence of obesity kidney disease and some were responsible, though not significantly associated with prevalence, for enhancing the risk of prevalence. However, the most responsible variable for the prevalence was family expenditure followed by family income, physical activity, age, process food consumption, blood pressure, and duration of diabetes. This was noted from factor analysis.

Conclusion
The present analysis was an attempt to identify some socioeconomic variables responsible for prevalence of obesity kidney disease among Bangladeshi adults of age 18 years and above. The adults visiting some diagnostic centres located in urban and semi-urban areas in Bangladesh were the investigating units and their number was 995. The data on residence, religion, gender, marital status, age ,education, occupation, family income, family expenditure, physical activity, food habit, smoking habit, prevalence of diabetes, duration of diabetes, blood pressure level including the different steps of treatment of needed for recovery of the health problem were recorded. adults who were involved in sedentary activity. The prevalence of obesity kidney disease was noted among 6.2% adults. This rate was more than 6.2% among all the above classified adults. However, the chance of prevalence was 48% more among males, 60% more among non-Muslims, 367% more among elderly people, 64% more among lower educated people, 89% more among smokers, 54% more among adults involved in sedentary activity, 105% more among diabetic patients, and 242% more among hypertensive adults. The chance was 220% more among adults suffering from diabetes for 15 years and above. These results were noted in calculating risk ratio. However, the identified most responsible factor for the prevalence was medium family expenditure, followed by medium family income, physical inactivity, over age, consumption of process food, hypertension, and longer duration of diabetes. This conclusion was drawn on the basis of risk ratio and higher absolute value of factor loading.
The prevalence of overweight and obesity are in increasing trend over the last decades in both developed and developing countries [6, 32, 33, 34, 35, and 36]. Prevalence has implications in increasing the rate of noncommunicable diseases including kidney diseases [1, 2, 3, 6, and 32]. Hence, strategies to decrease CKD need the inclusion of prevention technique of overweight and obesity [37]. But due to upward social mobility among the people of Bangladesh, the influences of obesity cannot be avoided but the intensity of the problem can be reduced to a great extent if proper action plan is formulated by the health planners to implement their plan in both urban and rural localities [38]. The social workers, medical practitioners, and other health workers can do a lot to encourage the people in leading healthy life. For this, people can be advised to avoid People can also be advised to do some sort of physical work and physical exercise if and when these are possible.