Effects of parental smoking on exercise systolic blood pressure in adolescents

Prevalences of cardiometabolic risk and lifestyle factors in young parents: evidence from a German birth cohort study

Background

Studies show that parents significantly impact their children’s health through their cardiometabolic risk profile and health behavior. There is only little information about the prevalence of cardiometabolic risk factors and lifestyle factors among new parents yet. The aims of this study are therefore to evaluate the prevalences of cardiometabolic risk factors in parents of infants in Germany and to examine their lifestyle and health behavior.

Methods

In the KUNO-Kids health study, an ongoing birth cohort, parents (n = 930 mothers and 769 fathers) were asked about cardiometabolic risk factors (obesity/hypertension/type 2 diabetes mellitus) and lifestyle factors (dietary/sports/smoking habits/alcohol consumption) during the first year after the birth of their children via questionnaires. Chi-square as well as fisher exact tests were conducted to analyse associations between lifestyle factors and cardiometabolic risk factors.

Results

34.2% of mothers and 58.5% of fathers were overweight or obese. In 11.8% of the families, at least one parent suffered from hypertension, in 2.4% from type 2 diabetes mellitus. One year after delivery, 8.5% of mothers were smoking, 6.9% showed a risky alcohol consumption (> 10 g/d). 16.0% of fathers were smoking 4 weeks after childbirth, 10.7% showed risky alcohol consumption (> 20 g/d). 21.6% of mothers carried out sports activity for more than 2 h a week then. Parental hypertension was linked to a higher prevalence of risky alcohol consumption, obesity to a lower prevalence of daily fruits consumption.

Conclusions

Cardiometabolic risk factors were widespread among new parents with obesity and overweight having the highest prevalences. A considerable number of parents also practiced an unhealthy lifestyle showing that there is potential for improvement to promote the healthy development of their children.

Associations between Second-Hand Tobacco Smoke Exposure and Cardiorespiratory Fitness, Physical Activity, and Respiratory Health in Children

BACKGROUND

Cardiorespiratory fitness (CRF) and physical activity (PA) are associated with a plethora of positive health effects. Many UK children fail to meet the recommended level of PA, with an observed decline in CRF levels over recent decades. Second-hand tobacco smoke (SHS) is responsible for a significant proportion of the worldwide burden of disease, but little is understood regarding the impact of SHS exposure on CRF and PA in children. The aim of this study was to test the associations between SHS exposure and CRF, PA, and respiratory health in children.

METHOD

Children (9-11 years) from UK primary schools in deprived areas participated (n = 104, 38 smoking households). Surveys determined household smoking, and exhaled carbon monoxide was used to indicate children's recent SHS exposure. CRF (VO_2peak) was assessed via maximal treadmill protocol using breath-by-breath analysis. Fractional exhaled nitric oxide and spirometry were utilised as indicators of respiratory health.

RESULTS

Linear regression models demonstrated that SHS exposure was negatively associated with allometrically scaled VO_2peak (B = -3.8, p = 0.030) but not PA or respiratory health.

CONCLUSION

The results indicate that SHS is detrimental to children's CRF; given that approximately one-third of children are regularly exposed to SHS, this important finding has implications for both public health and the sport and exercise sciences.

Children of Smoking and Non-Smoking Households' Perceptions of Physical Activity, Cardiorespiratory Fitness, and Exercise

Previous research has shown secondhand tobacco smoke to be detrimental to children’s health. This qualitative study aimed to explore children from low socioeconomic status (SES) families and their reasons for being physically active, attitudes towards physical activity (PA), fitness and exercise, perceived barriers and facilitators to PA, self-perceptions of fitness and physical ability, and how these differ for children from smoking and non-smoking households. A total of 38 children (9–11 years; 50% female; 42% smoking households) from the deprived areas of North West England participated in focus groups (n = 8), which were analysed by utilizing thematic analysis. The findings support hypothesised mediators of PA in children including self-efficacy, enjoyment, perceived benefit, and social support. Fewer than a quarter of all children were aware of the PA guidelines with varying explanations, while the majority of children perceived their own fitness to be high. Variances also emerged between important barriers (e.g., sedentary behaviour and environmental factors) and facilitators (e.g., psychological factors and PA opportunity) for children from smoking and non-smoking households. This unique study provided a voice to children from low SES and smoking households and these child perspectives could be used to create relevant and effective strategies for interventions to improve PA, fitness, and health.

Secondhand smoke exposure and higher blood pressure in children and adolescents participating in NHANES

We assessed the relationship between acute and intermittent secondhand tobacco smoke (SHS) exposure with child and adolescent blood pressure (BP). We analyzed cross-sectional data from 3579 children and adolescents aged 8-17 years participating in the National Health and Nutrition Examination Survey (NHANES) collected between 2007 and 2012, with SHS exposure assessed via serum cotinine (a biomarker for acute exposures) and urine NNAL (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol, a biomarker for intermittent exposures). BP percentiles and z-scores were calculated according to the 2017 guidelines established by the American Academy of Pediatrics. We used weighted linear regression accounting for the complex sampling weights from NHANES and adjusting for socio-demographic and clinical characteristics. Overall, 56% of the children were non-Hispanic white with a mean age of 12.6 years. There was approximately equal representation of boys and girls. Approximately 15.9% of participants lived in homes where smoking was present. In adjusted models, an interquartile range (IQR) increase in urinary NNAL was associated with 0.099 (95% CI: 0.033, 0.16) higher diastolic blood pressure (DBP) z-score, and with a 0.094 (95% CI: 0.011, 0.18) higher systolic blood pressure (SBP) z-score. The odds of being in the hypertensive range was 1.966 (95% CI: 1.31, 2.951) times greater among children with high NNAL exposures compared to those with undetectable NNAL. For serum cotinine, an IQR increase was associated with 0.097 (95% CI: 0.020, 0.17) higher DBP z-scores, but was not significantly associated with SBP z-scores. The associations of cotinine and NNAL with BP also differed by sex. Our findings provide the first characterization of the relationship between a major tobacco-specific metabolite, NNAL, and BP z-scores in a nationally representative population of US children.

Correlates of elevated blood pressure in healthy children: a systematic review

The prevalence of hypertension in children is increasing globally. Addressing this will require a robust understanding of associated risk factors. To this end, we conducted a systematic review to identify correlates of elevated blood pressure (BP) in children. Literature searches were conducted using pre-defined search terms from three academic databases. The abstract and full text of identified studies were screened for eligibility by two independent reviewers. A total of 100 studies were included in this systematic review. An assessment tool was first used to assess study quality; a narrative synthesis was then performed. We found a broad range of physiological, social and behavioural factors associated with elevated BP in children. The most common correlate observed was adiposity, suggesting that childhood obesity may be implicated in the increased prevalence of hypertension observed in children. However, the broad range of other factors identified underscores the multi-factorial aetiology of hypertension. Data from a broad range of studies showed that the correlates of hypertension in children are multi-factorial. Therefore, approaches aimed at preventing hypertension must in turn be multi-factorial to ensure that the burden of hypertension in childhood is addressed.

Reference Values for Exercise Systolic Blood Pressure in 12- to 17-Year-Old Adolescents

OBJECTIVE

In adults, blood pressure (BP) during exercise has prognostic advantages compared to resting BP, whereas its relevance for children has not been revealed as clearly. Because exercise BP among young subjects might be of clinical importance, we sought to determine reference values in adolescents.

METHODS

BP recordings at rest and during a cycle ergometer test (1.5W/kg) were assessed in 492 teenagers (12-17 years) in the Kiel EX.PRESS. Study (EXercise and PRESSure). The resting systolic BP (SBP) values at the 90th and 95th percentile of the German reference population were applied on our resting SBP distribution. The resulting resting SBP percentiles were then used to propose exercise SBP limits.

RESULTS

Of our group, 12.4% exhibited a resting SBP ≥ 90th reference percentile, with 7.9% ≥ 95th percentile. The corresponding age group- and sex-specific percentiles were assigned to the exercise SBP distribution resulting in reference values for high normal and elevated SBP (upper limit, girls/boys, mm Hg): 172/172 for 12-13 years, 174.7/177.3 for 14-15 years, 178.5/201.3 for 16-17 years). Using these limits, exercise SBP values were elevated in 8.1%, 5.5% were within the high normal range. Normal resting SBP but at least high normal exercise SBP was found in 7.7%. In contrast, 7.4% were high normal or hypertensive at rest but normotensive during exercise.

CONCLUSIONS

Exercise BP is expected to be of additional use for the evaluation of BP in younger age groups. As long as prognostic data for exercise BP in adolescents are not available, the limits proposed might be considered in clinical practice.