Genetic analyses of smoking initiation, persistence, quantity, and age-at-onset of regular cigarette use in Brazilian families: the Baependi Heart Study

Horimoto, Andréa Roseli Vançan Russo; Oliveira, Camila Maciel de; Giolo, Suely Ruiz; Soler, Júlia Maria Pavan; Andrade, Mariza de; Pereira, Alexandre C.

doi:10.1186/1471-2350-13-9

Cited by 20 publications

(14 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The overall phenotypic variance was estimated from the observed distribution of trait values in the sample, and was partitioned into genetic and environmental components using the observed covariance among family members, as V 5 2W s 2 a 1 Is 2 e , where V is an nxn matrix of the n individuals in the data set, 2W is the structuring matrix of the coefficient of relationship, and I is an identity matrix that represents the structuring matrix for s 2 e , the variance due to residual environmental factors. Estimates of the mean and variance components were obtained using maximum likelihood methods [47][48][49] . In a practical way, the heritability measures the level of correspondence between the phenotype and its genetic component.…”

Section: Methodsmentioning

confidence: 99%

Distribution and heritability of diurnal preference (chronotype) in a rural Brazilian family-based cohort, the Baependi study

et al. 2015

View full text Add to dashboard Cite

Diurnal preference (chronotype) is a useful instrument for studying circadian biology in humans. It harbours trait-like dimensions relating to circadian period and sleep homeostasis, but also has ontogenetic components (morningness increases with age). We used the Morningness-Eveningness questionnaire (MEQ) in the Baependi study, a family-based cohort study based in a small town in Minas Gerais, Brazil. The population is highly admixed and has a cohesive and conservative lifestyle. 825 individuals (497 female) aged 18-89 years (average 6 SD 5 46.4 6 16.3) and belonging to 112 different families participated in this study. The average MEQ score was 63.5 6 11.2 with a significant (P , 0.0001) linear increase with age. Morningness was significantly (P , 0.0001) higher in the rural (70.2 6 9.8) than in the municipal zone (62.6 6 11.1), and was also significantly (P 5 0.025) higher in male (64.6 6 10.9) than in female (62.8 6 11.2) participants. Thus, in spite of universal access to electricity, the Baependi population was strongly shifted towards morningness, particularly in the rural zone. Heritability of MEQ score was 0.48 when adjusted for sex and age, or 0.38 when adjusted for sex, age, and residential zone. The reported MEQ score heritability is more akin to those of previous twin studies than previous family studies.C ircadian period is viewed as a stable and reproducible quantitative trait in humans 1 . It has been found to have a high degree of heritability in all vertebrates where it has been studied 2-4 , and super-short periods have been shown to co-segregate with single-gene mutations both in humans 5 and in model animals 6 . Whilst circadian period may be determined experimentally in humans, most feasibly through the forced desynchrony protocol 7 , it is costly, intrusive, and time-consuming, and thus not a feasible option for large-scale human phenotyping. A more practical proxy for such studies is diurnal preference or chronotype, a self-reported questionnaire-based instrument that yields a numerical score on a scale ranging between extreme morning preference and extreme evening preference. It has been shown to correlate significantly not only with circadian phase, but also with circadian period 8 . However, the trait-like dimension of diurnal preference/chronotype is more complex, as in some individuals, morning versus evening preference results from differences in the build-up or dissipation of homeostatic sleep pressure rather than in circadian parameters [9][10][11] .In addition to its endophenotypic qualities, chronotype is also influenced by state-like variables, some of them of considerable interest to our understanding of the interaction between the circadian oscillator and the sleep homeostat and our external environment 12 . There is a firmly established relationship between chronotype and age, with a peak in eveningness in late adolescence 13 followed by a gradual increase in morningness 14 reflecting an altered relationship between the circadian system and sleep-wake timing 8 .The Morningn...

show abstract

Section: Methodsmentioning

confidence: 99%

Distribution and heritability of diurnal preference (chronotype) in a rural Brazilian family-based cohort, the Baependi study

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The traditional lifestyle, moderate and ongoing urbanisation, and very limited inward migration of this rural town make it a location of interest for the study of sleep quality and sleep characteristics. Since the beginning of this study in December 2005, a significant number of discoveries have been reported, such as the heritability of cardiovascular risk factors19, including sedentary behaviour20, smoking21, glycaemic control and arterial stiffness22, and obstructive sleep apnoea23. Moreover, we recently reported the heritability of chronotype in this population and found that genetic factors account for 48% of chronotype when adjusted for sex and age, or 38% when adjusted for sex, age and residential zone (rural versus municipal)24.…”

mentioning

confidence: 99%

Timing and quality of sleep in a rural Brazilian family-based cohort, the Baependi Heart Study

Beijamini

Knutson

Lorenzi-Filho

et al. 2016

Sci Rep

View full text Add to dashboard Cite

Sleep is modulated by several factors, including sex, age, and chronotype. It has been hypothesised that contemporary urban populations are under pressure towards shorter sleep duration and poorer sleep quality. Baependi is a small town in Brazil that provides a window of opportunity to study the influence of sleep patterns in a highly admixed rural population with a conservative lifestyle. We evaluated sleep characteristics, excessive daytime sleepiness, and chronotype using the Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale and Morningness-Eveningness Questionnaire questionnaires, respectively. The sample consisted of 1,334 subjects from the Baependi Heart study (41.5% male; age: 46.5 ± 16.2 y, range: 18–89 years). Average self-reported sleep duration was 07:07 ± 01:31 (bedtime 22:32 ± 01:27, wake up time: 06:17 ± 01:25 hh:min), sleep quality score was 4.9 + 3.2, chronotype was 63.6 ± 10.8 and daytime sleepiness was 7.4 ± 4.8. Despite a shift towards morningness in the population, chronotype remained associated with reported actual sleep timing. Age and sex modulated the ontogeny of sleep and chronotype, increasing age was associated with earlier sleep time and shorter sleep duration. Women slept longer and later, and reported poorer sleep quality than men (p < 0.0001). This study provides indirect evidence in support of the hypothesis that sleep timing was earlier prior to full urbanisation.

show abstract

“…Subsequent studies identified that age-at-onset is a useful trait for gene mapping of common complex diseases 21 and reported that heterogeneity in trait variances needs to be accounted for in the design and analyses of trait orientated gene finding studies. 22 Lifestyle factors, including physical activity 23 and smoking 24 have also been a focus of the study. The study has been extended to also include aspects of mental health, another major non-communicable disease complex forming a large burden to society.…”

Section: Findings To Datementioning

confidence: 99%

Cohort profile: the Baependi Heart Study—a family-based, highly admixed cohort study in a rural Brazilian town

et al. 2016

Self Cite

View full text Add to dashboard Cite

PurposeCardiovascular disease (CVD) is a major challenge to global health. The same epidemiological transition scenario is replayed as countries develop, but with variations based on environment, culture and ethnic mixture. The Baependi Heart Study was set up in 2005 to develop a longitudinal family-based cohort study that reflects on some of the genetic and lifestyle-related peculiarities of the Brazilian populations, in order to evaluate genetic and environmental influences on CVD risk factor traits.ParticipantsProbands were recruited in Baependi, a small rural town in the state of Minas Gerais, Brazil, following by first-degree and then increasingly more distant relatives. The first follow-up wave took place in 2010, and the second in 2016. At baseline, the study evaluated 1691 individuals across 95 families. Cross-sectional data have been collected for 2239 participants.Findings to dateEnvironmental and lifestyle factors and measures relevant to cardiovascular health have been reported. Having expanded beyond cardiovascular health outcomes, the phenotype datasets now include genetics, biochemistry, anthropometry, mental health, sleep and circadian rhythms. Many of these have yielded heritability estimates, and a shared genetic background of anxiety and depression has recently been published. In spite of universal access to electricity, the population has been found to be strongly shifted towards morningness compared with metropolitan areas.Future plansA new follow-up, marking 10 years of the study, is ongoing in 2016, in which data are collected as in 2010 (with the exception of the neuropsychiatric protocol). In addition to this, a novel questionnaire package collecting information about intelligence, personality and spirituality is being planned. The data set on circadian rhythms and sleep will be amended through additional questionnaires, actimetry, home sleep EEG recording and dim light melatonin onset (DLMO) analysis. Finally, the anthropometric measures will be expanded by adding three-dimensional facial photography, voice recording and anatomical brain MRI.

show abstract

Genetic analyses of smoking initiation, persistence, quantity, and age-at-onset of regular cigarette use in Brazilian families: the Baependi Heart Study

Cited by 20 publications

References 31 publications

Distribution and heritability of diurnal preference (chronotype) in a rural Brazilian family-based cohort, the Baependi study

Distribution and heritability of diurnal preference (chronotype) in a rural Brazilian family-based cohort, the Baependi study

Timing and quality of sleep in a rural Brazilian family-based cohort, the Baependi Heart Study

Cohort profile: the Baependi Heart Study—a family-based, highly admixed cohort study in a rural Brazilian town

Contact Info

Product

Resources

About