Childhood Exposure to Passive Smoking and Bone Health in Adulthood: The Cardiovascular Risk in Young Finns Study

Role of active and environmental tobacco smoke on susceptibility to osteoporosis in women undergoing dual-X-ray absorptiometry

PURPOSE

Current smoking is a risk factor for osteoporosis (Op), but few data are available regarding the passive smoke impact on Op susceptibility. This cross-sectional study aimed to evaluate the association between the smoking habits and Op in community-dwelling women undergoing dual-energy X-ray absorptiometry (DXA).

METHODS

On 01/06/2018, general practitioners from "COMEGEN" Medical Cooperative, Naples, Italy, selected the medical records from the last 10 years of women who had a measurement of bone mineral density performed and simultaneously completed a questionnaire about their smoking behaviour and their cohabiters'. The binary logistic regression analysis was used to estimate the role of passive smoke on the risk of Op, adjusting for age and body mass index (BMI).

RESULTS

Among 10,616 subjects, 3942 were currently smokers [CS; mean age 69.4 ± 10.4 years; BMI 27.0 ± 4.9 kg/m2], 873 were passive smokers (PS; mean age 67.8 ± 11.6 years; BMI 27.0 ± 4.9 kg/m2) and 5781 were never smokers (NS; mean age 67.8 ± 11.6 years; body mass index (BMI) 27.0 ± 4.9 kg/m2). Of all, 8562 women (mean age 70.3 ± 10.2 yrs; BMI 27.0 ± 4.9 kg/m2) received the Op diagnosis. PS showed an increased Op risk compared to NS [odds ratio (OR) 1.38 (1.14-1.67)] and comparable to CS [OR 1.02 (0.84-1.24)].

CONCLUSION

The study results demonstrate an association between passive smoke and Op in community-dwelling women already presenting with susceptibility to Op according to Italian essential assistance levels, suggesting that passive and active smoke are equivalent Op risk factors in women.

Early-life tobacco smoke elevating later-life osteoporosis risk: Mediated by telomere length and interplayed with genetic predisposition

INTRODUCTION

The growing prevalence of osteoporosis (OP) in an aging global population presents a significant public health concern. Tobacco smoke negatively affects bone turnover, leading to reduced bone mass and heightened OP and fracture risk. However, the impact of early-life tobacco smoke exposure on later-life OP risk remains unclear.

OBJECTIVES

This study was to explore the effects of early-life tobacco smoke exposure on incident OP risk in later life. The mediating role of telomere length (TL) and the interaction with genetic predisposition were also studied.

METHODS

Data on in utero tobacco smoke exposure (IUTSE) status and age of tobacco use initiation from the UK Biobank were used to estimate early-life tobacco smoke exposure. Incident OP cases were identified according to health-related records. Linear, Cox, and Laplace regression models were mainly used for data analysis.

RESULTS

Individuals with IUTSE showed a higher OP risk [hazard ratio (HR): 1.06, 95 % confidence interval (CI): 1.01, 1.11] and experienced earlier OP onset by 0.30 years [50th percentile difference = -0.30, 95 % CI: -0.51, -0.09] compared to those without. Participants initiating tobacco smoke in childhood, adolescence, and adulthood had 1.41 times (95 % CI: 1.23, 1.61), 1.17 times (95 % CI:1.10, 1.24), and 1.14 times (95 % CI: 1.07, 1.20) the risk of OP, respectively, compared to never smokers. They also experienced earlier OP onset by 2.16, 0.95, and 0.71 years, sequentially. The TL significantly mediated the early-life tobacco exposure and OP association. Significant joint and interactive effects were detected between early-life tobacco smoke exposure and genetic elements.

CONCLUSIONS

Our findings implicate that early-life tobacco smoke exposure elevates the later-life OP risk, mediated by telomere length and interplayed with genetic predisposition. These findings highlight the importance of early-life intervention against tobacco smoke exposure and ageing status for precise OP prevention, especially in individuals with a high genetic risk.

Association of secondhand smoke with fracture risk in community-dwelling nonsmoking adults in Korea

Although the detrimental effects of active smoking on bone health have been widely recognized, the impact of secondhand smoke exposure on fracture risk in non-smokers remains less understood. A total of 4843 nonsmokers aged 40-69 yr, who participated in the Korean Genome and Epidemiology Study from 2001 to 2018, were analyzed. The participants were categorized into two groups based on their exposure status to secondhand smoke: currently exposed and unexposed. The exposure group was subsequently divided into two subgroups based on the median weekly exposure time (high vs low). The incidence of new fractures was determined using self-reported questionnaires. The identified fractures were categorized according to the fracture site: overall, vertebral, hip, non-vertebral, and non-vertebral non-hip fractures. The mean age of the participants was 52.4 yr (84.1% women). Exposure to secondhand smoke was associated with an increased risk of fracture (adjusted hazard ratio [aHR]: 1.27, P = 0.028) after adjusting for multiple covariates including age, sex, BMI, household income, bone density of mid-shaft tibia, C-reactive protein, alcohol consumption, and fracture history. Secondhand smoke remained as a significant risk factor for fracture, independent of the major osteoporotic fracture probabilities estimated using a fracture risk assessment tool (aHR: 1.24, P = 0.038). The high exposure group had higher risk of fracture than that of the unexposed group (aHR: 1.33, P = 0.025), whereas the fracture risk did not differ significantly between low exposure and unexposed groups (aHR: 1.18, P = 0.253), suggesting a potential dose-response relationship. Secondhand smoke showed robust association with increased risk of non-vertebral (aHR: 1.37, P = 0.008) or non-vertebral non-hip fractures (aHR: 1.36, P = 0.013), while its association with vertebral fracture was attenuated (aHR: 1.03, P = 0.908). Secondhand smoke was associated with an elevated risk of fracture in nonsmokers, independent of clinical risk factors.

The links between parental smoking and childhood obesity: data of the longitudinal study of Australian children

Childhood obesity is one of the most concerning public health issues globally and its implications in mortality and morbidity in adulthood are increasingly important. This study uses a unique dataset of Australian children aged 4-16 to examine the impact of parental smoking on childhood obesity. It confirms a significant link between parental smoking (stronger for mothers) and higher obesity risk in children, regardless of income, age, family size, or birth order. Importantly, we explore whether heightened preference for unhealthy foods can mediate the effect of parental smoking. Our findings suggest that increased consumption of unhealthy foods among children can be associated with parental smoking.

Hypermethylation of the Bmp4 promoter dampens binding of HIF-1α and impairs its cardiac protective effects from oxidative stress in prenatally GC-exposed offspring

The exposure to an unhealthy environment in utero can lead to the occurrence of cardiovascular diseases in the offspring. Glucocorticoids (GC) are essential for normal development and maturation of fetal organs and is a first-line treatment for pregnant women affected by autoimmune diseases. However, excess prenatal GC exposure might program the development of fetal organs and cause a number of chronic diseases in later life. Our previous studies indicated that cardiac functions were significantly compromised in rat offspring prenatally exposed to the synthetic glucocorticoid dexamethasone (DEX), only after ischemia-reperfusion. In the present study, we further observed that DNA hypermethylation of bone morphogenetic protein 4 (Bmp4) promoter in cardiomyocytes caused by prenatal DEX exposure substantially dampened the binding activity of transcription factor HIF-1α induced by cardiac ischemia. Therefore, prenatal DEX exposure inhibits the induction of BMP4 upon I/R and attenuates the protective effects of BMP4 in cardiomyocytes, which eventually manifests as malfunction of the adult heart. Moreover, we employed two cardiac-specific Bmp4 knock-in mouse models and found that in vivo BMP4 overexpression could rescue the cardiac dysfunction caused by prenatal GC exposure. In depth mechanistic research revealed that BMP4 protects the cardiomyocytes from mitophagy and apoptosis by attenuating mitochondrial PGC-1α expression in a p-Smad and Parkin-dependent manner. These findings suggest that prenatal GC exposure increases the susceptibility of the offspring's heart to a "second strike" after birth, due to the failure of hypoxia-induced HIF-1α transactivation of the hypermethylated Bmp4 promoter in cardiomyocytes. Pretreatment with the DNA methylation inhibitor, 5-Aza-2'-deoxycytidine, could be a potential therapeutic method for this programming effect of GC exposure during pregnancy on neonatal cardiac dysfunction.

Dietary Saturated Fat and Bone Health in Young Adults: The Young Finns Cohort

Previous studies suggest that saturated fat (SFA) intake may negatively impact on bone. However, few human studies on the topic exist. Women and men aged 31-46 years from the Cardiovascular Risk in Young Finns study attended the peripheral quantitative computed tomography and ultrasound bone measurements in 2008 (n = 1884-1953, ~ 56% women). In addition, fracture diagnoses in 1980-2018 were searched for the national health care registers and 431 participants had at least one fracture. Food consumption was gathered with the 48-h dietary recall interviews and food frequency questionnaire in 1980-2007. In the present study, radial, tibial, and calcaneal bone traits, and fractures were examined relative to the long-term intake of SFA. No consistent associations were seen between bone outcomes and SFA intake that would have replicated in both women and men. The only evidence for differential distributions was seen in cortical density and cortical-to-total area ratio at the radial shaft, and speed of sound at the calcaneus, which were 0.1-0.4% higher in women in the lowest tertile of SFA intake compared with the highest tertile. In addition, among men, the odds ratio (OR) of fractures was greater in the second (OR 1.86, 95% confidence interval (CI) 1.03-3.33) and third tertile of SFA intake (OR 2.45, 95% CI 1.38-4.36) compared with the lowest tertile, independently of many risk factors of osteoporosis. In this observational study, we found no robust evidence of the associations of dietary long-term SFA intake with bone outcomes. Therefore, additional studies are needed to confirm the association of dietary SFA with bone health in humans.

The association between tobacco smoke exposure and vitamin D levels among US general population, 2001-2014: temporal variation and inequalities in population susceptibility

Tobacco smoking is endocrine-disrupting and may interfere with vitamin D endocrine systems (VDES), but supporting evidence is limited and inconsistent. Also, there is a lack of evidence on whether the association between tobacco smoke exposure and VD levels exhibit temporal variation. Data from the National Health and Nutrition Examination Survey was used to evaluate the association between tobacco smoke exposure and VD levels among US general participants from 2001 to 2014. We examined the linear association between serum cotinine and 25(OH)D concentrations, as well as relationship between tobacco smoke exposure categories (active, passive, non-smoking) with VD status (deficiency, inadequacy, sufficiency, intoxication), and assessed whether specific gender, age (3-11, 12-19, 20-59, ≥ 60 years), ethnicity/race, or body mass index (BMI) groups were disproportionately impacted. During 2001-2004, a decrease in both serum cotinine and passive smoking prevalence was observed, with a stabilized active smoking rate. The estimates for the association between tobacco smoke exposure and suboptimal VD levels increased over the study period. Overall results indicated that serum cotinine was negatively associated with 25(OH)D in all participants. Tobacco smoke exposure, including both active and passive smoking exposure, was associated with increased risk of VD deficiency. Moreover, active smoking was additionally related to enhanced risk of VD inadequacy. These associations showed some age and gender differences, with consistent and stronger associations observed in female adults. In contrast, effects of tobacco smoke exposure on VD levels were mostly negative or non-significant among children and adolescents aged 3-19 years. The percentage of US general population with active smoking exposure stabilized over the 14-year period and was still high. Tobacco smoke exposure may disrupt vitamin D levels with an increasing temporal trend in the risk. Our results also provided initial evidence of smoking exposure on VD intoxication, which needs to be further verified. Convincing studies have linked tobacco use exposure, to dysfunctional VDES accompanied with declined serum levels of VD metabolites. However, evidence on the association between tobacco smoke exposure and VD status was rather limited and inconsistent, and there were no researches to date that estimated the temporal variation of the association as well as the effects of smoke exposure on VD intoxication. This study analyzed national survey data, to evaluate the temporal trends in effects of tobacco smoke exposure on VD levels over a decade, and to comprehensively assess the impacts of tobacco smoke exposure on VD levels across specific subgroups. The evidence suggests that the prevalence of active smoking exposure stabilized over the 14-year period and was still high. Moreover, tobacco smoke exposure may disrupt vitamin D levels among general population, with an increasing temporal trend and age-, gender-differences in risk.

Childhood exposure to parental smoking and life-course overweight and central obesity

OBJECTIVE

To evaluate the association between childhood parental smoking exposure and the risk of overweight/obesity from childhood to adulthood.

METHODS

This study leverages the data from two longitudinal population based cohort studies, the Cardiovascular Risk in Young Finns Study between years 1980-2011/2012 (YFS; N = 2,303; baseline age 3-18 years) and the Special Turku Coronary Risk Factor Intervention Project between years 1989-2009/2010 (STRIP; N = 632; baseline age 7 months). Weight, height and waist circumference were measured from childhood to adulthood. Overweight/obesity was defined as body mass index ≥25 kg/m2 in adults and using the Cole criteria in children. Central obesity was defined as waist circumference > 100/90 cm in men/women and as a waist-to-height ratio > 0.50 in children. Statistical analyses were adjusted for age, sex, socioeconomic status, smoking, birth weight, parental ages, diet and physical activity.

RESULTS

Childhood parental smoking exposure was associated with increased risk for life-course overweight/obesity (YFS: RR1.13, 95%CI 1.02-1.24; STRIP: RR1.57, 95%CI 1.10-2.26) and central obesity (YFS: RR1.18, 95%CI 1.01-1.38; STRIP: RR1.45, 95%CI 0.98-2.15).

CONCLUSIONS

Childhood exposure to parental smoking is associated with increased risk of overweight/obesity over the life-course. KEY MESSAGES Exposure to parental smoking in childhood was associated with increased risk of overweight/obesity, central obesity and adiposity measured by skinfold thickness from childhood to adulthood.

Childhood and Adulthood Passive Smoking and Nonalcoholic Fatty Liver in Midlife: A 31-year Cohort Study

INTRODUCTION

Identifying early life risk factors remains key to the prevention of nonalcoholic fatty liver (hereinafter "fatty liver") in adulthood. However, the longitudinal association of childhood passive smoking with adult fatty liver is not studied. We examined the association of childhood and adulthood passive smoking with fatty liver in midlife.

METHODS

This was a 31-year prospective cohort study of 1,315 participants. Information on childhood passive smoking (parental smoking) was collected in 1980 (aged 3-18 years) and 1983 and adulthood passive smoking in 2001, 2007, and 2011. Fatty liver was determined by ultrasound in 2011 (aged 34-49 years).

RESULTS

The prevalence of fatty liver was 16.3%. Both childhood and adulthood passive smoking were associated with higher risk of fatty liver, adjusting for potential confounders such as age, sex, childhood socioeconomic status, and adulthood physical activity and alcohol consumption (relative risk = 1.41, 95% confidence interval: 1.01-1.97 for childhood; 1.35, 1.01-1.82 for adulthood). Individuals with persistent exposure to passive smoking between childhood and adulthood had the highest risk (relative risk = 1.99, 95% confidence interval: 1.14-3.45) compared with those without passive smoking in either childhood or adulthood.

DISCUSSION

Passive smoking in both child and adult lives are associated with increased risk of adult fatty liver, suggesting that the prevention of passive smoking should start as early as possible and maintain throughout lifetime.

Maternal and Neonatal Factors Affecting Bone Mineral Content of Indonesian Term Newborns

Background: Interactions between the genome and intrauterine environment can affect bone mineralization in newborns and even in adult life. Several studies show that intrauterine fetal bone mineralization or early postnatal bone condition influences the risk of osteoporosis in later life. Objectives: To determine whole body bone mineral content (WB BMC) and factors that influence neonatal WB BMC in Indonesian term newborns. Subjects/Methods: A cross-sectional study was conducted in Dr. Sardjito General Hospital, Yogyakarta, Indonesia. A total of 45 term, appropriate for gestational age (AGA) newborns were included in this study. BMC was assessed by dual-energy x-ray absorptiometry (DXA) in the first week of life. Weight (g), length (cm) and head circumference (cm) were measured at birth. Data on maternal characteristics were obtained from the maternal health records or reported by the mothers. Results: WB BMC measured in the present study (mean ± SD: 33.2 ± 9.3 g) was lower than WB BMC of similar populations in developed countries. Multiple linear regression showed that birth weight, birth length, and gestational age had a positive association with WB BMC (p = 0.048, 0.017, and <0.001, respectively), while maternal cigarette exposure had a negative association with WB BMC (p = 0.012). Male infants had significantly higher of WB BMC than female (p = 0.025). These determinants contribute to 55% variability of WB BMC. Conclusions: WB BMC in Indonesian term newborns is lower than populations in developed countries. Birth weight, length, gestational age, sex, and maternal cigarette exposure during pregnancy are significantly associated with WB BMC observed in Indonesian newborns.

Association between maternal smoking and child bone mineral density: a systematic review and meta-analysis

Maternal smoking during pregnancy has detrimental effects on fetal development. The current review examined the differences in offspring's bone mineral density (BMD) between mothers smoked during pregnancy and those who did not. A systematic review and meta-analysis on the studies investigating the influence of maternal smoking during pregnancy on children or neonates' bone measures published up to October 30, 2018, was performed. BMD results measured at different body sites were pooled and then fixed or random effect models were used based on the presence of heterogeneity. The desired pooled effect size was the offspring's BMD mean difference with 95% confidence interval between smoker and non-smoker mothers. Sensitivity analysis was performed for birth weight and current weight, two important mediator/confounders causing heterogeneity. Overall, eight studies consisting of 17,931 participants aged from infancy to 18 years were included. According to the fixed effect model, the mean of BMD in offspring whose mothers smoked during pregnancy was 0.01 g/cm² lower than those with non-smoker mothers (95% CI = - 0.02 to - 0.002). However, subgroup meta-analysis adjusted for birth weight and current weight demonstrated no significant mean difference between BMD of children with smoker and non-smoker mothers (d = 0.06, 95% CI = -0.04 to 0.16, p value = 0.25 and d = - 0.005, 95% CI = - 0.01 to 0.004, p value = 0.28, respectively). According to available studies, it is suggested that maternal smoking during pregnancy does not have direct effect on the offspring's BMD. Instead, this association might be confounded by other factors such as placental weight, birth weight, and current body size of children.

Paternal impact on the life course development of obesity and type 2 diabetes in the offspring

The aetiologies of obesity and type 2 diabetes are incredibly complex, but the potential role of paternal influences remains relatively understudied. A better understanding of paternal influences on offspring risk of obesity and type 2 diabetes could have profound implications for public health, clinical practice and society. In this review, we outline potential biological and social mechanisms through which fathers might exert an impact on the health of their offspring. We also present a systematically compiled overview of the current evidence linking paternal factors to offspring development of obesity and type 2 diabetes throughout the life course. Although evidence is accumulating to support paternal associations with offspring outcomes, more high-quality research is needed to overcome specific methodological challenges and provide stronger causal evidence.