Helping hospitalized smokers in Hong Kong quit smoking by understanding their risk perception, behaviour, and attitudes related to smoking.

AIM: To understand the risk perceptions, behaviour, attitudes, and experiences related to smoking among hospitalized Chinese smokers. BACKGROUND: Understanding hospitalized smokers' perceptions of risks associated with smoking, along with their behaviour, attitudes, and smoking-related experiences, is essential prerequisite to design effective interventions to help them quit smoking. DESIGN: A phenomenological research design was adopted. METHODS: A purposive sampling approach was used. Between May 2016-January 2017, 30 hospitalized smokers were invited for an interview. RESULTS: Four themes were generated: (a) associations between perception of illness and smoking; (b) perceived support from healthcare professionals to quit smoking; (c) impact of hospitalization on behaviour, attitudes, and experiences; and (d) perceived barriers to quitting smoking. CONCLUSION: Development of an innovative intervention that helps to demystify misconceptions about smoking through brief interventions and active referrals is recommended to enhance the effectiveness of healthcare professionals promoting smoking cessation for hospitalized smokers. IMPACT: To date, no study examining smoking behaviour among hospitalized patients in Hong Kong has been conducted. Misconceptions about smoking and health, barriers to quitting that outweighed perceived benefits, lack of support from healthcare professionals, and difficulty overcoming withdrawal symptoms or cigarette cravings precluded hospitalized smokers sustaining smoking abstinence after discharge. Smoking is detrimental to physical health. Smoking cessation has beneficial effects on treatment efficacy and prognosis and helps to reduce the economic burden on society from smoking-attributable diseases.

Recommendations on prevention and screening for breast cancer in Hong Kong.

In Hong Kong, breast cancer is the most common cancer among women and poses a significant health care burden. The Cancer Expert Working Group on Cancer Prevention and Screening (CEWG) was set up in 2002 by the Cancer Coordinating Committee to review and assess local and international scientific evidence, and to formulate recommendations for cancer prevention and screening. After considering the local epidemiology, emerging scientific evidence, and local and overseas screening practices, the CEWG concluded that it was unclear whether population-based breast cancer screening did more harm than good in local asymptomatic women at average risk. The CEWG considers that there is insufficient evidence to recommend for or against population-based mammography screening for such individuals. Women who consider breast cancer screening should be adequately informed about the benefits and harms. The CEWG recommends that all women adopt primary preventive measures, be breast aware, and seek timely medical attention for suspicious symptoms. For women at high risk of breast cancer, such as carriers of confirmed BRCA1/2 deleterious mutations and those with a family history of breast cancer, the CEWG recommends that they seek doctor's advice for annual mammography screening and the age at which the process should commence. Additional annual screening by magnetic resonance imaging is recommended for confirmed BRCA1/2 mutation carriers or women who have undergone radiation therapy to the chest between the age of 10 and 30 years. Women at moderate risk of breast cancer should discuss with doctors the pros and cons of breast cancer screening before making an informed decision about mammography screening every 2 to 3 years.

Development of a community-based network to promote smoking cessation among female smokers in Hong Kong.

BACKGROUND: There is a need for population-based smoking cessation interventions targeting female smokers in Hong Kong. This study describes the development of a community-based network to promote smoking cessation among female smokers in Hong Kong. METHODS: Local women's organizations collaborated to launch a project to provide gender-specific smoking cessation services. In the first phase of the project, the Women Against Tobacco Taskforce (WATT) was created. In the second phase, a smoking cessation training curriculum was developed and female volunteers were trained. The third and final phase included the provision of gender-specific smoking cessation counseling services in Hong Kong. RESULTS: A need assessment survey with 623 workers and volunteers of WATT members was carried out to develop a gender-specific smoking cessation training curriculum. A 1-day training workshop to 28 WATT affiliates who provided brief cessation counseling in the community was organized. Fourteen organizations (69 service units) agreed to form a network by joining WATT to promote smoking cessation and increase awareness of the specific health risks among female smokers. CONCLUSIONS: The community-based network to promote smoking cessation was effective in helping female smokers to quit smoking or reduce their cigarette consumption. The results also suggest that this community model of promoting gender-specific smoking cessation services is feasible. TRIAL REGISTRATION: Clinicaltrials.gov ID NCT02968199 (Retrospectively registered on November 16, 2016).

Cohort Profile: Hong Kong Department of Health Elderly Health Service Cohort.

The Department of Health Elderly Health Service Cohort in Hong Kong was set up to promote understanding of ageing in a global context, to exploit the role of Hong Kong as a sentinel for populations currently experiencing very rapid economic development, to provide a developed non-Western 'social laboratory' where empirically derived hypotheses can be tested and to leverage the different patterns of common chronic diseases between East and West to generate novel hypotheses about their determinants. The initial cohort enrolled from July 1998 to the end of December 2001 includes 66 820 people aged 65 years or older, forming about 9% of the population of this age. A comprehensive health assessment was made at enrollment and then repeated regularly on an ongoing basis. The health assessment included a comprehensive assessment of lifestyle, social circumstances, physical health and mental health, including an assessment of cognition and depressive symptoms. Health services use and deaths have been obtained by record linkage and confirmed, where necessary, by telephone interview. Currently, the data are not publicly available; we would welcome collaborations and research proposals.

Systematic differences among never, occasional and moderate alcohol users in southern China, and its use in alcohol research: a cross-sectional study.

BACKGROUND: Western observational studies show moderate alcohol use, compared with never use, positively associated with health. Moderate users differ systematically from others, making these observations vulnerable to confounding. Observations from other contexts may help distinguish whether these associations are confounded. To assess whether southern Chinese would provide a more suitable setting to examine the association of moderate alcohol use with health, we compared never alcohol users with moderate alcohol users and occasional users in this setting. METHODS: We used age-adjusted multinomial regression to assess sex-stratified associations of alcohol use (never, occasional (<1 occasion/week), moderate (≤140 g ethanol/week for women and ≤210 g for men)) with health attributes and indicators in the Guangzhou Biobank Cohort Study (2003-2008) (n=26 361). RESULTS: Among men, moderate alcohol users, when compared with never users, had slightly lower socioeconomic position and unhealthier lifestyle. Conversely, occasional alcohol users, when compared with never users, had higher socioeconomic position and healthier lifestyle. Among women, when compared with never users, both occasional and moderate users had higher socioeconomic position and healthier lifestyle. However, all alcohol users for both sexes, when compared with never users, were more likely to be ever smokers and to be exposed to secondhand smoke. CONCLUSIONS: Observations in alcohol epidemiology may be affected by confounding due to contextually specific systematic differences. Results from a particular setting should not be interpreted as causal unless they are verified in different populations and, preferably, in non-observational studies.

A cluster analysis of patterns of objectively measured physical activity in Hong Kong.

OBJECTIVE: The health benefits of exercise are clear. In targeting interventions it would be valuable to know whether characteristic patterns of physical activity (PA) are associated with particular population subgroups. The present study used cluster analysis to identify characteristic hourly PA patterns measured by accelerometer. DESIGN: Cross-sectional design. SETTING: Objectively measured PA in Hong Kong adults. SUBJECTS: Four-day accelerometer data were collected during 2009 to 2011 for 1714 participants in Hong Kong (mean age 44?2 years, 45?9% male). RESULTS: Two clusters were identified, one more active than the other. The 'active cluster' (n 480) was characterized by a routine PA pattern on weekdays and a more active and varied pattern on weekends; the other, the 'less active cluster' (n 1234), by a consistently low PA pattern on both weekdays and weekends with little variation from day to day. Demographic, lifestyle, PA level and health characteristics of the two clusters were compared. They differed in age, sex, smoking, income and level of PA required at work. The odds of having any chronic health conditions was lower for the active group (adjusted OR50?62, 95% CI 0?46, 0?84) but the two groups did not differ in terms of specific chronic health conditions or obesity. CONCLUSIONS: Implications are drawn for targeting exercise promotion programmes at the population level.

Perspectives on family health, happiness and harmony (3H) among Hong Kong Chinese people: a qualitative study.

Family harmony, an important Confucian ideal in Chinese society is believed to determine family happiness and therefore health, but is this accurate? This is a qualitative study of 41 Hong Kong Chinese family members. Individual recorded interviews were thematically analysed describing perceived interactions between harmony, happiness and health. Family harmony comprised four components: communication, mutual respect, lack of conflict and family time [notably 'Gou tong' (in Cantonese )-opportunity and willingness to spend time together-requiring good interpersonal communication, emphasized by female respondents]. Lack of conflict was emphasized, while diverse values, parenting styles and financial difficulties were common causes of conflict. Respect required reciprocity. Family happiness comprised four elements: family harmony, an important pre-requisite; mutual caring and supportive orientation; sense of security emphasizing financial security in middle-class versus sense of togetherness in lower social class groups and contentment. Healthy families were harmonious; 'typical' (children/two-parent/two-grandparent); happy; caring and respectful, with individual health and healthy behaviours. Family harmony, happiness and health are interrelated and built on a communicative, respectful, caring and contented set of attitudes, in particular allowing for family time. Harmony is apparently a core element of good family functioning.

Obstructive lung disease does not increase lung cancer mortality among female never-smokers in Hong Kong.

SETTING: High lung cancer mortality is observed among female never-smokers in Hong Kong. OBJECTIVE: To examine the relationship between obstructive lung disease (chronic obstructive pulmonary disease and/or asthma) and lung cancer mortality by sex and smoking status. DESIGN: A cohort of elderly clients (aged ≥65 years) in a health maintenance programme were followed prospectively through linkage with the territory-wide death registry for causes of death, using identity card number as the unique identifier. RESULTS: After 516,055 person-years of follow-up, respectively 1297, 872 and 1908 deaths were caused by lung cancer, other tobacco-related malignancies and non-tobacco-related malignancies. In the overall analysis, obstructive lung disease was independently associated with mortality due to lung cancer (aHR 1.86, P < 0.001) after adjustment for potential confounders. However, no association was detected among female never-smokers (HR 0.97, P = 0.909), in sharp contrast with female ever-smokers, male never-smokers and male ever-smokers (HR 1.98, 2.34 and 2.09, respectively, P from 0.047 to <0.001). Consistent results were observed after exclusion of all deaths in the initial 3 years. CONCLUSION: Obstructive lung disease exerted differential effects on lung cancer mortality across different sex and smoking subgroups in this Asian population, with a conspicuous absence of effect among female never-smokers.

Performance of the international physical activity questionnaire (short form) in subgroups of the Hong Kong chinese population.

BACKGROUND: The International Physical Activity Questionnaire (IPAQ-SF) has been validated and recommended as an efficient method to assess physical activity, but its validity has not been investigated in different population subgroups. We examined variations in IPAQ validity in the Hong Kong Chinese population by six factors: sex, age, job status, educational level, body mass index (BMI), and visceral fat level (VFL). METHODS: A total of 1,270 adults (aged 42.9 ± SD 14.4 years, 46.1% male) completed the Chinese version of IPAQ (IPAQ-C) and wore an accelerometer (ActiGraph) for four days afterwards. The IPAQ-C and the ActiGraph were compared in terms of estimated Metabolic Equivalent Task minutes per week (MET-min/wk), minutes spent in activity of moderate or vigorous intensity (MVPA), and agreement in the classification of physical activity. RESULTS: The overall Spearman correlation (ρ) of between the IPAQ-C and ActiGraph was low (0.11 ± 0.03; range in subgroups 0.06-0.24) and was the highest among high VFL participants (0.24 ± 0.05). Difference between self-reported and ActiGraph-derived MET-min/wk (overall 2966 ± 140) was the smallest among participants with tertiary education (1804 ± 208). When physical activity was categorized into over or under 150 min/wk, overall agreement between self-report and accelerometer was 81.3% (± 1.1%; subgroup range: 77.2%-91.4%); agreement was the highest among those who were employed full-time in physically demanding jobs (91.4% ± 2.7%). CONCLUSIONS: Sex, age, job status, educational level, and obesity were found to influence the criterion validity of IPAQ-C, yet none of the subgroups showed good validity (ρ = 0.06 to 0.24). IPAQ-SF validity is questionable in our Chinese population.

Childhood meat eating and inflammatory markers: the Guangzhou Biobank Cohort Study.

BACKGROUND: We hypothesized that socio-economic development could, via nutritionally driven levels of pubertal sex-steroids, promote a pro-inflammatory state among men but not women in developing countries. We tested this hypothesis, using recalled childhood meat eating as a proxy for childhood nutrition, in southern China. METHODS: We used multivariable linear regression in the Guangzhou Biobank Cohort Study phase 3 (2006-8) to examine the adjusted associations of recalled childhood meat eating, <1/week (n = 5,023), about once per week (n = 3,592) and almost daily (n = 1,252), with white blood cell count and its differentials among older (≥ 50 years) men (n = 2,498) and women (n = 7,369). RESULTS: Adjusted for age, childhood socio-economic position, education and smoking, childhood meat eating had sex-specific associations with white blood cell count and lymphocyte count, but not granulocyte count. Men with childhood meat eating almost daily compared to <1/week had higher white blood cell count (0.33 109/L, 95% confidence interval (CI) 0.10 to 0.56) and higher lymphocyte count (0.16 109/L, 95% CI 0.07 to 0.25). Adjustment for obesity slightly attenuated these associations. CONCLUSION: If confirmed, this hypothesis implies that economic development and the associated improvements in nutrition at puberty may be less beneficial among men than women; consistent with the widening sex differentials in life expectancy with economic development.

Leg length and age of puberty among men and women from a developing population: the Guangzhou Biobank Cohort study.

OBJECTIVES: Leg length and relative leg length are considered to be reliable markers of prepubertal living conditions. Cessation of leg growth, driven by estrogen, occurs earlier in puberty in girls than boys. We hypothesized that leg length and relative leg length, as sitting height to leg ratio, might have sex-specific associations with age of puberty. METHODS: We used multivariable linear regression in 10,046 older (>or=50 years) Chinese from the Guangzhou Biobank Cohort Study (Phase 3) to examine the associations of recalled age of puberty (women: age of menarche, and men: mean age of first nocturnal emission, voice breaking, and first pubic hair) with subischeal leg length, sitting height to leg ratio, and sitting height. RESULTS: Leg length and sitting height to leg ratio had different associations with age of puberty in men and women (P-values for interaction <0.001), but sitting height did not. Per year earlier puberty, legs were longer among men by 0.09 cm (95% confidence interval (CI) 0.01-0.18) and shorter among women by -0.16 cm (95% CI -0.20 to -0.12). Further adjustment for age, hip size (as a marker of buttock fat), and several markers of childhood conditions did not obviate the difference in association by sex. CONCLUSIONS: Adult leg length and relative leg length (sitting height to leg ratio) may be biomarkers of different exposures in men and women, with corresponding implications for their interpretation as a biomarker of early life exposures.

Determinants of infant growth: Evidence from Hong Kong's "Children of 1997" birth cohort.

PURPOSE: A high rate of infant growth may be associated with adult cardiovascular disease. We investigated factors associated with infant weight growth in a large sample from the recently transitioned population of Hong Kong. METHODS: We used a nonlinear shape invariant model with random effects among 5949 term, singletons (77% follow-up) from a population-representative Hong Kong Chinese birth cohort "Children of 1997" to investigate factors associated with weight growth in the first year of life. RESULTS: Overall birth weight was lower but infant growth was more rapid than the 2006 WHO standards. Shorter gestation and lower birth order were associated with lower birth weight and faster infant growth. Female sex, maternal smoking in pregnancy, and a mother born in Hong Kong were associated with lower birth weight, but not with faster growth. Higher maternal education was associated with faster infant growth, grades 10-11 (1.03, 95% confidence interval [CI] = 1.03-1.05), greater than or equal to grade12 (1.07, CI = 1.04-1.09) compared with less than or equal to grade 9. CONCLUSIONS: Infant growth may respond more rapidly to socio-economic development than birth weight. Whether mother's education is associated with rapid infant growth via current conditions or her own "constitution" is unclear, nevertheless we believe this study illustrates the importance of contextually specific research for understanding the determinants of population health.

An overview of the Guangzhou biobank cohort study-cardiovascular disease subcohort (GBCS-CVD): a platform for multidisciplinary collaboration.

The Guangzhou Biobank Cohort Study (GBCS, n=30 519, age >or=50 years) was established to examine the effects of genetic and environmental influences on health problems and chronic disease development. Guangzhou is undergoing massive economic development, but from a baseline that had remained unchanged for millennia. The Cardiovascular Disease Subcohort (GBCS-CVD) consists of 2000 participants who have been intensively phenotyped including a range of surrogate markers of vascular disease, including carotid artery intima-media thickness, cerebral artery stenoses, arterial stiffness, ankle-to-brachial blood pressure index and albuminuria, as well as coagulatory and inflammatory markers. Plasma and leukocytes are stored in liquid nitrogen for future studies. Preliminary demographic data show the female volunteers are younger than the male ones, but present with greater levels of adiposity including central obesity (31 vs 16%). Women had more body fat (33 vs 24%) and associated levels of adipokines. Despite this, body mass index and hip circumferences were similar, which contrasts with Caucasian populations. Men had more physician-diagnosed vascular disease (6.1 vs 2.5%), hypertension (42 vs 34%) and hyperglycaemia (36.6 vs 29.6%) than the women, but were less insulin resistant. In men, smoking (40 vs 2%) and drinking alcohol (67 vs 50%) was more common and they also had lower energy expenditures. The genotype distributions of the 15 typed single nucleotide polymorphisms were all in Hardy-Weinberg equilibrium. This article describes the rationale and methodology for the study. Given the comprehensive characterization of demographic and psychosocial determinants and biochemistry, the study provides a unique platform for multidisciplinary collaboration in a highly dynamic setting.

A socio-historical hypothesis for the diabetes epidemic in Chinese--preliminary observations from Hong Kong as a natural experiment.

It has been hypothesized that the emerging epidemic of diabetes in economically transitioning or recently transitioned populations is due to mismatch between developmental and mature environments. We took advantage of migration within an ethnically homogenous population to investigate this hypothesis, and the potentially modifying role of postnatal growth conditions, proxied by greater height. We used multivariable logistic regression in a population-based cross-sectional study from 1994 to 1996 of 2,341 long-term Hong Kong residents aged 25-74 years, either born in contemporaneously developed Hong Kong or migrants from economically undeveloped Guangdong. Migrant status was not associated with clinically diagnosed diabetes, odds ratio 1.05 (95% confidence interval 0.69-1.58) in adult migrants compared to Hong Kong-born natives and 1.22 (0.83-1.80) in preadult migrants, adjusted for age, sex, socio-economic position, and lifestyle. However, the association of diabetes with migrant status varied with height, suggesting a potentially complex relationship between indicators of prenatal and postnatal nutritional exposures. Compared to tall Hong Kong-born natives, the odds ratio of diabetes was 2.36 (1.20-4.61) in tall migrants, 1.94 (1.07-3.53) in short Hong Kong-born natives, but 1.04 (0.48-2.23) in short adult migrants. Additionally adjusting for body mass index and waist-hip ratio had little effect, apart from attenuating the association between short height and diabetes prevalence in Hong Kong-born natives. Whether the current epidemic of diabetes is a long-standing effect of such mismatch or a "first-generation through effect" generated by rapid economic development causing disproportionate growth remains to be determined.

Household smoking practices of parents with young children, and predictors of poor household smoking practices.

OBJECTIVES: Household smoking practices of parents have a major impact on the health of their young children. This study examined the characteristics and household smoking practices of parents with children aged 4-5 years, and identified the predictive factors of poor household smoking practices among Chinese parents in Hong Kong. STUDY DESIGN: Cross-sectional survey. METHODS: Smoking parents with young children from a 1997 birth cohort were re-contacted for a telephone interview to assess their household smoking practices. RESULTS: Among 1149 smoking parents from 1049 families, 898 (85.6%) parents smoked at home. Of these, 339 (37.8%) parents reported smoking at home but not near (i.e. within 3 metres) their children, and 559 (62.2%) reported that they smoked at home without any restrictions. Logistic regression revealed that the predictors of poor household smoking practices were: smoking mother [odds ratio (OR) 4.92, P<0.001]; children born with normal birth weight (OR 2.62, P<0.05); having more than one child (OR 1.70, P=0.01); being a daily smoker (OR 18.96, P<0.0001); smoking >or= 11 cigarettes per day (OR 3.10, P<0.0001); having a higher Fagerstorm nicotine dependence score (OR 4.57-4.86, P<0.01); and having a smoking partner (OR 2.78, P<0.05). CONCLUSIONS: A high proportion of smoking parents with young children display poor smoking practices at home. It is of the utmost importance that community education and smoking cessation services are targeted at these smoking parents to promote smoke-free families.

Are height and leg length universal markers of childhood conditions? The Guangzhou Biobank cohort study.

OBJECTIVE: In developed western populations longer legs have been shown to be a marker of better early childhood conditions. In the first generations to experience the epidemiologic transition and associated economic development, epigenetic constraints on growth might preclude improved childhood conditions from increasing leg growth or height. DESIGN, SETTING AND PARTICIPANTS: Multivariable linear regression was used to assess the association of parental growth environment, proxied by parental literacy, and childhood conditions, proxied by parental possessions, with leg length, sitting height and height in a cross-sectional sample from 2005-6 of 9998 Chinese people aged at least 50 years from phase 2 of the Guangzhou Biobank Cohort Study. MAIN RESULTS: Adjusted for age and sex, the association of childhood conditions with leg length and height varied with parental literacy (interaction p values <0.01 and 0.03), but not for sitting height (p value 0.43), with statistically significant trends (p values <0.01) for parental possessions to be associated with longer legs and greater height only in the offspring of two literate parents where legs were longer by 0.56 cm (95% CI 0.27 to 0.86) and height greater by 1.16 cm (95% CI 0.74 to 1.58) for participants with most, compared with least, parental possessions in childhood. CONCLUSIONS: Epigenetic influences originating in earlier generations may constrain growth during the infancy and/or childhood phases in very recently developed populations. Neither height nor leg length should be assumed to be consistent proxies of early life environment with corresponding implications for economic history, the aetiology of some chronic diseases and the monitoring of population health.

BMI compared with central obesity indicators in relation to diabetes and hypertension in Asians.

OBJECTIVE: To compare BMI with waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-stature ratio (WSR) in association with diabetes or hypertension. METHODS AND PROCEDURES: Cross-sectional data from 16 cohorts from the DECODA (Diabetes Epidemiology: Collaborative Analysis of Diagnostic criteria in Asia) study, comprising 9,095 men and 11,732 women, aged 35-74 years, of different ethnicities were included in this meta-analysis. RESULTS: Age-adjusted odds ratios (ORs) for diabetes in men (women) for 1 s.d. increase in BMI, WC, WHR, and WSR were 1.52 (1.59), 1.54 (1.70), 1.53 (1.50), and 1.62 (1.70), respectively; and the corresponding ORs for hypertension were 1.68 (1.55), 1.66 (1.51), 1.45 (1.28), and 1.63 (1.50). Paired homogeneity tests (BMI with each of the three) adjusted for age and cohort showed that diabetes had stronger association with WSR than BMI (P=0.001) in men but with WC and WSR than BMI (both P<0.05) in women. Hypertension had stronger association with BMI than WHR in men (P<0.001) and had the strongest with BMI than the others (WHR P<0.001; WSR P<0.01; and WC P<0.05) in women. Areas under the receiver operating characteristic (ROC) curves adjusted for age and cohort were slightly larger for diabetes for WSR 0.735 (0.748) in men (women) and WC 0.749 (women only) than BMI 0.725 (0.742) while for hypertension larger for BMI 0.760 (0.766) than WHR 0.748 (0.751), but their 95% CIs were all overlapped. DISCUSSION: WSR was stronger than BMI in association with diabetes, but these indicators were equally strongly associated with hypertension in Asians.

Is leg length a biomarker of childhood conditions in older Chinese women? The Guangzhou Biobank Cohort Study.

OBJECTIVE: In developed western populations longer legs have been shown to be a biomarker of better early childhood conditions. It was hypothesised that in transitioning populations better childhood conditions may bring forward puberty and thus decrease leg length, counteracting the overall positive effect of a favourable childhood environment on leg growth. DESIGN: Structural equation modelling was used to assess the interrelationship of age, education, father's job, age of menarche and leg length in a cross-sectional sample of 7273 Chinese women aged at least 50 years from the Guangzhou Biobank Cohort Study. RESULTS: Leg length had no significant association with education or father's occupation on bivariable testing. After including age of menarche in the model, education was associated with longer legs (0.45 cm longer per 10 years of education, 95% CI 0.20 to 0.71). Education was also associated with younger age of menarche (1.21 years younger per 10 years of education, 95% CI 1.09 to 1.34), which was in turn associated with shorter legs (0.23 cm shorter per year of menarche earlier, 95% CI 0.18 to 0.27). CONCLUSIONS: In older Chinese women leg length is not a universal biomarker of childhood conditions, when proxied by her educational level and father's occupation. Nutritionally driven epigenetic influences operating over generations may constrain growth in very recently developed populations. Given the impact of childhood conditions on health, and the dearth of long-term records outside the industrialised world, a greater understanding of the influences on growth in the developing world is required.