Obesity, physical activity and prediabetes in adult children of people with diabetes

ABSTRACT Objectives: Determine prevalence of obesity / overweight, physical activity (PA) and prediabetes in adult children of parents with type 2 diabetes; identify differences according to sociodemographic variables, and describe the relationship of obesity/overweight with fasting glucose (FG) and glycosylated hemoglobin (A1C). Methods: Cross-sectional study in 30 Mexican families with 53 participating adult children. Obesity / overweight was determined with Body Mass Index (BMI), Waist Circumference (WC) and body fat percentage (BFP); PA with the short International Physical Activity Questionnaire (IPAQ), and prediabetes with FG. Results: 64% of participants presented obesity / overweight, 32% low PA, and 19% prediabetes. Men had higher WC than women (U= 219, p= 0.03). Women showed more BFP than men (U= 142, p <0.01). Blood glucose was related to BFP (rs= 0.336, p < 0.05), the A1C with the BMI (rs= 0.417, p <0.01), WC (rs= 0.394, p<0.01), BFP (rs= 0.494, p<0.01) and intense PA (rs= - 0.285, p<0.05). Conclusions: High prevalence of obesity / overweight and low PA were found. The FG was related only to BFP and A1C, in addition to BMI, WC and inversely with intense BP. It is recommended to modify the educational strategies of nursing at a family level.

and cardiovascular alterations secondary to obesity; adipose tissue during obesity has been associated with insulin resistance and with diabetes mellitus (13) . Electrical impedance is a method to evaluate body composition that estimates total body fat, which can also influence health risks.
Physical inactivity is the fourth risk factor for global mortality, and is estimated to be the main cause of 27% of diabetes cases (14) . Physical activity helps control body weight, and decreases the risk of type 2 diabetes, the risk of cardiovascular diseases, and metabolic syndrome.
According to its intensity, PA can be mild, moderate or intense; the higher the performance, the greater the benefits. On the other hand, it is convenient to point out that regardless of the PA performed, spending a lot of time on sedentary behaviors (which are not presented in this work) can additionally increase health risks.
Inadequate nutrition also requires special attention.
In each of the stages of the life cycle, it is necessary to maintain a balance between the energy consumed and the energy expended. The improvement of dietary habits is a problem for the whole society, and not only each of the individuals that compose it; therefore, it requires a population-based, multisectoral, multidisciplinary approach adapted to cultural circumstances (15) . It is recognized that eating goes much further than satisfying hunger; eating is a social factor that works as a means of relationship between people within a culture, with behaviors towards eating acquired in the family and social context (16) .
Among the non-modifiable risk factors, family history is a very useful variable to identify individuals at risk, since this disease occurs more frequently in the relatives of an individual diagnosed, than in those who are not. In addition, it is recognized that relatives of people with diabetes follow lifestyle patterns similar to those of the diagnosed patients (17) , what increases the risk. The family becomes a mechanism that can favor or disfavor health. Family is a fundamental element in the development of health and self-care behaviors, it represents emotional, affective, adaptive, informative, economic and functional support (18) . People at risk require knowledge, tools and skills for self-care, so that health professionals can encourage behaviors.
Tamaulipas is one of the states with the highest prevalence of type 2 diabetes mellitus in Mexico, (3) and there is a knowledge gap regarding the pre-condition that prediabetes represents and the importance of the family context. The understanding of this phenomenon in the south of the state, through its risk factors, will help to provide an initial panorama of the problem, which will allow proposing strategies that favor, in this age group, Compeán-Ortiz L, Trujillo-Olivera L, Valles-Medina A, Reséndiz-González E, García-Solano B, Del Angel B.
the informed decisions and the resolution of problems at the family level, to achieve an impact in reducing the disease. Therefore, the present work was conducted with the following objective: to determine prevalence of obesity / overweight, physical activity, and prediabetes in adult children of people with diabetes mellitus type 2; identify differences according to sociodemographic variables (sex, age, occupation, and type of family) and describe the relationship of obesity / overweight and physical activity with blood glucose and glycosylated hemoglobin (A1c).

Methods
This article is derived from the first year of a network To evaluate overweight and obesity by BMI, the World Health Organization (WHO) criteria were used (20) . Central obesity was determined based on WC, with the criteria proposed by the International Diabetes Federation (1) . The risk of cardiovascular diseases was determined according to the WC, using the WHO cut-off points, and validated cut-off points were used for the classification of obesity according to the percentage of body fat.
To determine PA, the short version of the IPAQ Questionnaire was applied (21) , which measures three specific types of activity in the last seven days that are walking, moderate activity, and vigorous activity. The continuous indicator of PA is expressed in MET-minutes / week. The METs are a way to calculate the energy requirements, it is calculated by multiplying the MET corresponding to the type of activity, by the minutes of execution in a day or a week. To obtain the total PA continuously, a summation of the METs-week / minutes was made using the Ainsworth formula (22) : eight "minutes of vigorous activity" on days of vigorous activity; for moderate activity the formula is four "minutes of moderate activity" days of moderate activity; and for walking, 3.3 "walk minutes" walk days.
To classify PA by categories, the level of PA was calculated: high, for those individuals who had vigorous activity at least three days a week, with at least 1500 MET min/week, or seven days of any combination of PA reaching at least 3000 MET-minutes / week; moderate, for those who had three or more days of intense activity of at least 20 minutes per day, or five or more days of moderate activity, or walking of at least 30 minutes per day, or five or more days of any combination of PA reaching at least one PA total of 600 MET-minutes / week; and lastly, low level for those who did not meet the above criteria (21) .
Afterwards, the participants were given an appointment to go to the laboratory after a 12-hour fast for a blood glucose test and A1C. The criteria proposed by the American Diabetes Association were used as a reference framework to determine prediabetes (4) , in which an amount of 70 -100 mg / dl of fasting glucose is considered "normal", 100 -125 mg / dl is considered "impaired fasting glucose or prediabetes", and 126 or more is considered "diabetes".
The A1C test was performed to establish a reference frame of the average blood glucose that the relatives had during the twelve weeks before the measurement.

Results
The sample consisted of 30 families; the majority were nuclear families (Table 1). In total, there were 53 participant adult children of people with DM2. The sociodemographic characteristics is presented in Table 2, where the occupation of housewife and the informal sector, the youngest age group, and the female sex stand out. and 6% were strongly suspected of diabetes.
To determine differences in obesity and PA according to sex, age, occupation, and type of family, In PA, a difference was found (U= 218, p=0.02) only in moderate activity, where more activity was observed in men than in women. No significant differences in PA were found according to age or occupation (p > 0.05).
Regarding the relationship between obesity / overweight with blood glucose and A1, the data of their indicators are presented in the Table 4.

Discussion
One of the outstanding findings of this study was the high prevalence of obesity / overweight due to BMI, and abdominal obesity due to WC in adult children of people with diabetes, which is consistent with the 2012 National Health and Nutrition Survey in Mexico, where reports state that seven out of ten adults over 20 are overweight or obese, according to BMI and seven out of ten suffer from abdominal obesity according to WC (3) . Even though BMI did not show significant differences, one was observed in WC, where men had more centimeters than women; while women showed higher percentage of body fat. This finding shows health risks because the central adiposity is associated with metabolic and cardiovascular alterations secondary to obesity, it is also more frequent to find insulin resistance -a condition that will favor the presence of prediabetes and diabetes -in adults when the fat is accumulated in the abdomen (13) .  (18) . The family as a support network can represent a potential for the reduction of disease problems, since it promotes greater social participation and community inter-relations (24) .
About a quarter of the participants in this study had impaired glucose for prediabetes, and suspected DM2 with the fasting glucose test. This result is similar to that reported in Mexico, (2) where 20% had their glucose altered in fasting for prediabetes. This also coincides with findings reported by other authors, (10) in a study conducted in the northern area of the city of Jalisco, with a sample of 423 participants. The prevalence reported by these authors was around 20%. Our finding is also congruent with some international studies (9) . However, it is also recognized that the prevalence found in our study does not coincide with other international studies, such as those in the United States (5) and England (6) , where prevalence of prediabetes was reported above 30%. A possible explanation of the differences could be the sample size.
Blood glucose was related only to body fat, but not BMI, WC or PA; however, positive relationship of A1C with BMI, WC, body fat, and an inverse relationship was observed with intense PA. Considering that, the blood