Jayakaran S. Job

Waterpipe smoking and nicotine exposure: A review of the current evidence

The waterpipe, also known as shisha, hookah, narghile, goza, and hubble bubble, has long been used for tobacco consumption in the Middle East, India, and parts of Asia, and more recently has been introduced into the smokeless tobacco market in western nations. We reviewed the published literature on waterpipe use to estimate daily nicotine exposure among adult waterpipe smokers. We identified six recent studies that measured the nicotine or cotinine levels associated with waterpipe smoking in four countries (Lebanon, Jordan, Kuwait, and India). Four of these studies directly measured nicotine or cotinine levels in human subjects. The remaining two studies used smoking machines to measure the nicotine yield in smoking condensate produced by the waterpipe. Meta-analysis of the human data indicated that daily use of the waterpipe produced a 24-hr urinary cotinine level of 0.785 microg/ml (95% CI = 0.578-0.991 microg/ml), a nicotine absorption rate equivalent to smoking 10 cigarettes/day (95% CI = 7-13 cigarettes/day). Even among subjects who were not daily waterpipe smokers, a single session of waterpipe use produced a urinary cotinine level that was equivalent to smoking two cigarettes in one day. Estimates of the nicotine produced by waterpipe use can vary because of burn temperature, type of tobacco, waterpipe design, individual smoking pattern, and duration of the waterpipe smoking habit. Our quantitative synthesis of the limited human data from four nations indicates that daily use of waterpipes produces nicotine absorption of a magnitude similar to that produced by daily cigarette use.

Mentoring Cambodian and Lao health professionals in tobacco control leadership and research skills

Design: The aim of the programme was to ultimately affect public health practice and policy in the Kingdom of Cambodia and Lao People’s Democratic Republic (Lao PDR) by training key health professionals to conduct tobacco control research. Setting: Encouraged by the World Health Organization’s Framework Convention on Tobacco Control, a global partnership formed to build effective leadership to develop and guide national tobacco control agendas. The partners were the Ministries of Health (Cambodia and Lao PDR), non-government organisations (Adventist Development and Relief Agency in Cambodia and Laos) and an academic institution (Loma Linda University, Loma Linda, California, USA). Subjects: 16 health professionals, 10 from Cambodia and 6 from Lao PDR, were selected by local advisory committees to enter a two-year, intensive tobacco research graduate certificate and research training programme. Intervention: We developed a “Global Tobacco Control Methods” (GTCM) 28 unit certificate programme that was offered in five sessions from September 2003 to September 2005 at the National Institute of Public Health, Phnom Penh, Cambodia. As part of their coursework, the 16 trainees actively participated in the development and implementation of two research projects. In the first project, “Healthy Doc Healthy Patient” (HDHP), trainees adapted an existing, self-administered questionnaire designed to assess health practices and beliefs of medical students in Cambodia and Lao PDR. The second project involved the design of a national prevalence of tobacco use and health beliefs study in Cambodia using a multi-stage, cluster sample method. Trainees were sponsored to attend and present at international tobacco control conferences to enhance their awareness of the tobacco epidemic. Results: As of September 2005, 14 trainees (8 from Cambodia and 6 from Lao PDR) completed the courses in the GTCM certificate programme. The HDHP study sampled four medical school classes (years 3, 4, 5 and 6) in both Cambodia (n  =  330, 71.1% response rate) and Lao PDR (n  =  386, 87.3% response rate). As part of the Cambodian adult tobacco prevalence study in Cambodia, 13 988 adults (ages ⩾ 18 years) were interviewed from all 22 provinces during the summer of 2005. Over the two years, more than half of the trainees participated substantially in local and regional tobacco control and research activities. Programme challenges included the trainees’ limited English language and computer proficiency skills, both of which improved during the two years. Conclusions: With the successful completion of the certificate programme, the remaining two years of the grant will be used to prepare the trainees for positions of leadership within their Ministries of Health and other agencies to implement effective tobacco control policies based on locally-derived research findings.

Tobacco use among adults in Cambodia: evidence for a tobacco epidemic among women

OBJECTIVE To identify the demographic characteristics of current tobacco users in Cambodia, particularly women, and to explore the reasons for current tobacco use in demographic subgroups of the Cambodian population. METHODS We used a stratified three-stage cluster sample of 13,988 adults aged 18 years and older from all provinces in 2005-2006. Participants completed an interviewer-administered survey that contained items on all forms of tobacco use and on health and lifestyle variables. Multivariable regression analysis was performed to identify demographic predictors of tobacco use. FINDINGS Cigarette smoking occurred among 48.0% of men and 3.6% of women. We estimated that 560,482 women (95% confidence interval, CI: 504,783 to 616 180) currently chewed tobacco (typically as a component of betel quid) and that the prevalence more than doubles with each decade of adulthood up to the point that about half of all older women chew tobacco. Both men and women cited the influence of older relatives as their primary reason for starting to use tobacco. About one out of five rural women who used chewing tobacco started their habit for relief from morning sickness. The highest prevalence of chewing tobacco among women was seen among midwives (67.9%) and traditional healers (47.2%). High rates (66.8%) of cigarette and pipe tobacco use occurred among ethnic minorities who represent hill tribes found throughout south-east Asia. CONCLUSION The tobacco epidemic in Cambodia extends far beyond cigarette smoking in men. Tobacco control that focuses only on cigarettes will not address the health burden from smokeless tobacco use in women that may be an integral part of cultural, familial, and traditional medicine practices.

Successful immunization of infants at 6 months of age with high dose edmonston-zagreb measles vaccine

A group of 2097 Haitian infants 6 to 11 months of age were randomized to receive Schwarz or Edmonston-Zagreb strain measles vaccines containing 10− to 500-fold more vaccine viral particles than standard potency vaccines. No unusual adverse reactions were noted. Edmonston-Zagreb vaccines were more effective than equivalent doses of Schwarz vaccines as measured by the proportion of vaccinated children with measles antibody concentrations ≥200 mIU/ml 2 months after vaccination and the persistence of antibody at 18 to 24 months of age. High titer Edmonston-Zagreb vaccine administered at 6 months of age induced antibody concentrations ≥200 mIU/ml in 83% of infants by plaque reduction neutralization and 93% of infants by enzyme-linked immunosor-bent assay with high rates of antibody persistence at 12 to 24 months of age. The World Health Organization recommends high titer Edmonston-Zagreb measles vaccines for routine use at 6 months of age in areas where measles is an important cause of mortality in young infants.

Estimating the Impact of Smoking Cessation During Pregnancy: The San Bernardino County Experience

We examined the relation between maternal smoking and adverse infant outcomes [low birth weight (LBW), and preterm birth (PTB)] during 2007–2008 in San Bernardino County, California—the largest county in the contiguous United States which has one of the highest rates of infant mortality in California. Using birth certificate data, we identified 1,430 mothers in 2007 and 1,355 in 2008 who smoked during pregnancy. We assessed the effect of never smoking and smoking cessation during pregnancy relative to smoking during pregnancy for the 1,843/1,798 LBW, and 3,480/3,238 PTB’s recorded for 2007/2008, respectively. To describe the effect of quitting smoking during pregnancy, we calculated the exposure impact number for smoking during pregnancy. Major findings are: (1) relative to smoking during pregnancy, significantly lower risk of LBW among never smoking mothers [OR, year: 0.56, 2007; 0.54, 2008] and for smoking cessation during pregnancy [0.57, 2007; 0.72, 2008]; (2) relative to smoking during pregnancy, significantly lower risk of PTB was found for never smoking mothers [0.68, 2007; 0.68, 2008] and for smoking cessation during pregnancy [0.69, 2007; 0.69, 2008]; (3) an exposure impact assessment indicating each LBW or PTB outcome in the county could have been prevented either by at least 35 mothers quitting smoking during pregnancy or by 25 mothers being never smokers during pre-pregnancy. Our findings identify an important burden of adverse infant outcomes due to maternal smoking in San Bernardino County that can be effectively decreased by maternal smoking cessation.

Cigarette smoking and tuberculosis in Cambodia: findings from a national sample.

BackgroundCambodia has very high rates of tuberculosis and smoked tobacco use among adults. Efforts to control both tobacco use and tuberculosis in Cambodia need to be informed by nationally representative data. Our objective is to examine the relation between daily cigarette smoking and lifetime tuberculosis (TB) history in a national sample of adults in Cambodia.MethodsIn 2011, a multi-stage, cluster sample of 15,615 adults (ages 15 years and older) from all regions of Cambodia were administered the Global Adult Tobacco Survey by interviewers from the National Institute of Statistics of Cambodia.ResultsOur findings include: 1) among daily smokers, a significant positive relation between TB and number of cigarettes smoked per day (OR = 1.70 [95% CI 1.01, 2.87]) and pack-years of smoking (OR = 1.53 [95% CI 1.05, 2.25]) 2) a non-significant 58% increase in odds of ever having being diagnosed with TB among men who smoked manufactured cigarettes (OR = 1.58 [95% CI 0.97, 2.58]).ConclusionIn Cambodia, manufactured cigarette smoking was associated with lifetime TB infection and the association was most evident among the heaviest smokers (> 1 pack per day, > 30 pack years).

Maternal use of cigarettes, pipes, and smokeless tobacco associated with higher infant mortality rates in Cambodia.

In the Western Pacific Region, rural women use loose tobacco in betel quid chewing and pipe smoking. We examined the relation between maternal use of tobacco and infant mortality (IM) in a national sample of 24 296 birth outcomes in adult women (n = 6013) in Cambodia. We found that (1) age-adjusted odds of IM were higher for maternal use of any tobacco (odds ratio [OR] = 1.69; 95% confidence interval [CI] = 1.27-2.26); (2) age-adjusted odds of IM were higher for cigarette use (OR = 2.54; 95% CI = 1.54- 4.1), use of pipes (OR = 3.09; [95% CI = 1.86-5.11]), and betel quid chewing (OR = 1.55; 95% CI = 1.10-2.17); and (3) these associations remained after multivariable adjustment for environmental tobacco smoke, malnutrition, ethnicity, religion, marital status, education, income, occupation, and urban/rural dwelling. In addition to finding the established association with cigarettes, we also found that maternal use of smokeless tobacco and pipes was associated with higher rates of infant death in Cambodia.

Patterns of alcohol and tobacco use in Cambodia.

Few studies have considered whether the habitual use of tobacco in Southeast Asia is part of an established pattern of addiction that includes regular alcohol use. As part of a national survey of adult tobacco use in Cambodia (n = 13 988), we found that men who smoked were 2 times more likely to have drank alcohol in the past week (odds ratio = 2.53, 95% confidence interval = 2.10-3.03). By age 18 to 25 years, 47% of male smokers drank alcohol, and this pattern of alcohol and tobacco use increased to >55% through the fifth decade. Women using smokeless tobacco with betel quid were more likely to be alcohol drinkers (odds ratio = 1.49, 95% confidence interval = 1.12-1.98). Past week’s drinking declined by late middle age and was associated with lower education and being currently married; the behavior was lower in some ethnic groups (ie, Cham). Our findings indicate an important association between alcohol and tobacco use, and raise the possibility that reducing alcohol consumption can be an important component of tobacco control.

Validity and reliability of survey items and pictograms for use in a national household survey of tobacco use in Cambodia.

The validity of survey measures of smoked and smokeless tobacco use in the Western Pacific Region is often unknown. We conducted a validation study (n = 201) in a random sample of rural adults in Cambodia. A comparison with salivary cotinine indicated (1) that survey items and pictograms of current tobacco use had an 87% (95% confidence interval [CI] = 78%-93%) sensitivity, 94% specificity (95% CI = 87%-98%), and 93% (95% CI = 85%-97%) positive predictive value in detecting cotinine levels >10 ng/mL; (2) a positive correlation with number of cigarettes smoked (R = 0.34; P = .01); and (3) a positive correlation with the amount of tobacco chewed (R = 0.44; P = .02). The validity of the index for the amount of smokeless tobacco used was enhanced by adding to the index the data from pictograms that were utilized to help participants estimate the amount of loose tobacco used per session. These tobacco items and pictograms were found to have excellent reliability (κ = 0.80-1) over 2 to 3 weeks. Interviewer-administered survey items and pictograms can provide an accurate, quantitative measure of smoked and smokeless tobacco use in rural Cambodia.

Adult tobacco cessation in Cambodia: I. Determinants of quitting tobacco use.

This study determined factors associated with quitting tobacco in Cambodia, a country with a high prevalence of men who smoke and women who use smokeless tobacco. As part of a nationwide survey, face-to-face interviews were conducted with 5145 current and 447 former tobacco users who had quit for ≥2 years. Determinants of quitting in multivariate analyses were age >48 years, age at initiation >25 years, ≥7 years of education, income ≥1 US dollar per day, professional (odds ratio [OR] = 2.52; 95% confidence interval [CI] = 1.27-5.01) or labor (OR = 1.98, 95% CI = 1.10-3.56) occupations, and heart disease (OR = 1.94; 95% CI = 1.10, 3.42). Smokeless tobacco users were 10-fold less likely to quit (OR = 0.10; 95% = CI 0.05-0.20) than smokers. In conclusion, tobacco cessation among Cambodians was lower than in nations with decades of comprehensive tobacco control policies. Tobacco cessation programs and policies should include all forms of tobacco and target young to middle-aged users before onset of disease and premature death.