Blood pressure levels and body mass index in Brazilian adults with Down syndrome

ABSTRACT CONTEXT AND OBJECTIVE: Increased life expectancy among people with Down syndrome (DS) has introduced new environmental factors that may affect blood pressure (BP) and/or lead to obesity in this population. The aim here was to investigate BP levels and body mass index (BMI) in adults with DS, correlating these data with the patients' sex and age. DESIGN AND SETTING: Analytical cross-sectional observational study conducted in special schools in Curitiba (PR), Brazil. METHODS: 97 adult patients were included. BP was measured in accordance with the established guidelines. BMI was calculated by dividing the weight by the height squared (kg/m2). RESULTS: Sex had no influence on BMI; nor did systolic BP (SBP) or diastolic BP (DBP). The age range was from 18 to 56 years. No correlation was observed between increasing age and greater BMI or BP. Eighty-six individuals (88.7%) presented normal BP, eleven (11.3%) prehypertension and none hypertension. Twenty patients (20.4%) presented BP lower than 90 × 60 mmHg. BMI ranged from 18 to 48 kg/m2 (mean of 28.8 ± 3.92 kg/m2): 21.9% had normal weight; 40.7% were overweight; and 25.3% had obesity class I, 9.9% class II and 2.2% class III. Higher BMI was associated with significantly greater SBP and DBP (P = 0.0175 and P = 0.0015). CONCLUSION: Sex and age did not influence SBP, DBP or BMI in Brazilian adults with DS. Higher BMI was associated with greater BP (both systolic and diastolic).


INTRODUCTION
Over the last five decades, there has been a trend toward longer survival among individuals with Down syndrome (DS). [1][2][3] In developed countries, recent estimates have indicated that their average age at death is greater than 50 years. 2,3 Reduced institutionalization with increased mobility and integration into society has also played a role. 1,4,5 DS is a multiorgan disorder, affecting the heart and vascular system both structurally and functionally. 6 Conditions such as obesity, mobility restrictions, depression, hypothyroidism and Alzheimer's disease are known to become increasingly prevalent in later life, 7 including increased blood pressure (BP) and body mass index (BMI). There are a few studies evaluating blood pressure in adults with DS that have reported that their BP is lower than that of the general population and people with other forms of mental handicap. However, some of these studies were conducted many years ago. 8,9 Today, individuals with DS are exposed to different environmental factors such as stress, fast foods, greater social inclusion and new challenges that can affect BP and cause obesity.
Draheim et al. 10 investigated 52 DS patients and reported that systolic and diastolic BP were significantly lower in adults with DS than in a matched control group; and that their body mass index (BMI) was 31.0 ± 6, which was significantly higher than that of the controls (28.0 ± 7). There are no studies on this topic conducted in Brazil.

OBJECTIVE
In the present study, we investigated the levels of diastolic/systolic BP and BMI among noninstitutionalized adults with DS in Curitiba, Brazil, correlating the findings with the patients' sex and age.

METHODS
This study had an observational cross-sectional design and was approved by the local research ethics committee (Positivo University, number 297.349/2013). The parents or guardians of all participants signed informed consent forms.
The study population comprised adults with DS over the age of 18 years who were being followed up at two institutions: Associação de Pais e Amigos dos Excepcionais (APAE-PR) and Associação Reviver, both in Curitiba, Paraná. The parents were sent a letter proposing the study. If they agreed, they signed the consent form and the patient was included in the study. In a brief questionnaire, the participants answered questions about the presence of diagnosed hypertension, smoking and alcohol consumption. The participants received guidance on healthy habits and were encouraged to practice physical activity. The study was conducted over the period from May 2013 to September 2013. To obtain the patients' body weight and height, we used an electric scale and a tape measure. Patients who presented abnormal BP measurements received a letter from the school, in which their parents were advised to seek the municipal health service for the patients' BP to be measured. The healthcare professional assigned to the special school was also informed about the findings. All the patients received information about proper nutrition and physical exercise for maintaining their health.
The data distribution was analyzed using the Kolmogorov-Smirnov test. The results were expressed as the mean and stan-

RESULTS
Among the 97 DS patients, 49 (51%) were male. There were no statistically significant differences according to sex with regard to evaluations on BMI (P = 0.84), systolic blood pressure (SBP) (P = 0.64) or diastolic blood pressure (DBP) (P = 0.33), as demonstrated in Table 1.
The population age range was from 18 to 56 years, with a mean age of 26.5 ± 6.52 years; 74.2% were less than or equal to 30 years of age ( Table 1). The statistical analysis showed that there was no association between increasing age and higher BMI (P = 0.64), or between increasing age and SBP (P = 0.45) or DBP (P = 0.80).
The systemic arterial pressure ratios of the 97 patients evaluated in this study ranged from 72/36 mmHg to 132/88 mmHg.
Eighty-six of them (88.7%) presented BP below the "optimal" reference value (120/80 mmHg) for individuals with normal BP, as recommended through JNC-7. 11 Eleven patients (11.3%) were classified as presenting prehypertension and no patient presented hypertension ( Higher BMI was associated with significant greater SBP and DBP (P = 0.0175 and P = 0.0015, respectively). Figure 1 shows the SBP and DBP values according to BMI variation. No

DISCUSSION
In this study, we evaluated the BP and the BMI of adults with DS.
We showed that the diastolic and systolic BPs were lower among individuals with DS and that high BMI was associated with increased BP.
In terms of BP, in our study, the majority (88.7%) of the patients had BP below the recommended levels, which is consistent with the findings of other authors. 8 It is natural to emphasize the importance of consistent exercise, good diet, community involvement and regular health examinations for these individuals. In a study on physical inactivity among adults with intellectual disability, Draheim et al. 18 reported that less than 46% of the men and women participated in the recommended amount of physical activity and that no adults older than 30 years reported participation in vigorous physical activity. However, Fujiura et al. 19 founded that there were no strong links between BMI, diet and exercise among adults with DS. They discovered a significant link between friendships or access to recreation and BMI, concluding that community interactions had a major effect on health. In our view, healthy behavior should be stimulated. It is to be expected that a specific approach is needed to get these people interested and motivated to change their lifestyle. Therefore, development of specific programs for DS patients that may be conducted in schools is necessary.

CONCLUSION
In our study, we found that sex and age did not influence SBP, DBP or BMI among Brazilian adults with DS. We observed that our DS patients presented high BMI. Furthermore, higher BMI was associated with higher systolic and diastolic BP.