Nicotine dependence, socioeconomic status, lifestyle behaviours and lifetime quit attempts among adult smokers in South Africa

Background. Smoking cessation is a complex process influenced by factors such as smokers’ nicotine dependence levels, socioeconomic status (SES) and other lifestyle behaviours. Little is known about these relationships in South Africa (SA).Objectives. To explore the relationship between nicotine dependence, SES, lifestyle behaviours and lifetime quit attempts among adult smokers in SA.Methods. This study used data from 2 651 participants aged ≥16 years in the 2011 South African Social Attitudes Survey. Information on SES (measured by asset ownership), binge drinking, physical activity, fruit and vegetable intake, intention to quit smoking and lifetime quit attempts was extracted. Nicotine dependence was measured using the Heaviness of Smoking Index (HSI). All data were weighted to account for the complex survey design and to yield nationally representative estimates. Data analysis included binary logistic regression with high nicotine dependence (HND) defined as HSI ≥4 and lifetime quit attempts as separate outcomes.Results. The prevalence of smoking was 20.1% (31.6% for males and 9.5% for females), and was highest in the mixed-ancestry group (37.0%). Overall, 14.5% of smokers had HND, with a higher proportion in the high-SES group. The odds of HND increased with every 10  years of smoking history (odds ratio (OR) 2.05; 95% confidence interval (CI) 1.40 - 3.00) but decreased among participants who reported frequent physical activity (OR 0.4; 95% CI 0.18 - 0.86) and those who planned to quit (OR 0.37; 95% CI 0.19 - 0.75). Quit attempts were more likely among participants who reported frequent fruit and vegetable intake (OR 1.8; 95% CI 1.07 - 2.98) and less likely among those reporting binge drinking (OR 0.31; 95% CI 0.16 - 0.59) or assessed as having HND (OR 0.32; 95% CI 0.17 - 0.58).Conclusions. Most adult smokers in SA have low nicotine dependence. However, the association of HND with high SES in this study suggests that although cessation treatment based on an integrated lifestyle behavioural intervention package may suffice for most smokers, a more intense cessation treatment package is needed for smokers of higher SES

E-cigarette advertising exposure among South African adults in 2017 : findings from a nationally representative cross-sectional survey

OBJECTIVES : In South Africa, the Control of Tobacco and Electronic Delivery Systems Bill seeks to regulate e-cigarettes as tobacco products, including their advertising, promotion and sponsorship. Population data on e-cigarette advertising in South Africa are needed to inform public health programs, practice and policy. We examined self-reported e-cigarette advertising exposure during 2017. DESIGN Cross-sectional. SETTING : Household-based survey. PARTICIPANTS : 3063 individuals who participated in the 2017 South African Social Attitudes survey, a nationally representative, in-person survey of the non-institutionalised civilian adult population aged ≥16 years EXPOSURE ‘In the past 12 months, have you seen advertisements or promotions for e-cigarettes (including e-shisha, e-pipe) on any of the following media: newspapers/ magazines, billboards, in the malls or any other source?’ MAIN OUTCOMES : Beliefs and attitudes regarding e-cigarettes. FINDINGS : Participants’ mean age was 37.7 years. Overall, 20.1% reported exposure to e-cigarette advertisements. By age, exposure was most prevalent among those aged 16–19 years (24.6%). Top sources of exposure among those exposed were stores, 40.7%; malls, 30.9%; and television, 32.5%. Of those aware of e-cigarettes, 61.2% believed ‘e-cigarette advertisements and promotion may make adolescents think of smoking traditional cigarettes’; 62.7% believed that ‘e-cigarette advertisements and promotions may make ex-smokers think of starting smoking cigarettes again’; and 59.5% supported the statement that ‘e-cigarette smoking should be banned indoors just as traditional cigarette smoking’. Notably, teens aged 16–19 reported the lowest prevalence (49.0%) of those believing that ‘e-cigarette advertisements and promotion may make adolescents think of smoking traditional cigarettes’, whereas this percentage was highest among those aged 55–64 years (73.2%). CONCLUSION : Comprehensive regulatory efforts are needed to address e-cigarette advertising, marketing and sponsorship in order to protect public health. The urgent enactment of the new tobacco control legislation, The Control of Tobacco Products and Electronic Delivery Systems Bill, can help reduce youth exposure to e-cigarette advertising in South Africa.http://bmjopen.bmj.comam2022School of Health Systems and Public Health (SHSPH

Estimating the changing disease burden attributable to smoking in South Africa for 2000, 2006 and 2012

Background. Ongoing quantification of the disease burden attributable to smoking is important to monitor and strengthen tobacco control policies. Objectives. To estimate the attributable burden due to smoking in South Africa for 2000, 2006 and 2012. Methods. We estimated attributable burden due to smoking for selected causes of death in South African (SA) adults aged ≥35 years for 2000, 2006 and 2012. We combined smoking prevalence results from 15 national surveys (1998 - 2017) and smoking impact ratios using national mortality rates. Relative risks between smoking and select causes of death were derived from local and international data. Results. Smoking prevalence declined from 25.0% in 1998 (40.5% in males, 10.9% in females) to 19.4% in 2012 (31.9% in males, 7.9% in females), but plateaued after 2010. In 2012 tobacco smoking caused an estimated 31 078 deaths (23 444 in males and 7 634 in females), accounting for 6.9% of total deaths of all ages (17.3% of deaths in adults aged ≥35 years), a 10.5% decline overall since 2000 (7% in males; 18% in females). Age-standardised mortality rates (and disability-adjusted life years (DALYs)) similarly declined in all population groups but remained high in the coloured population. Chronic obstructive pulmonary disease accounted for most tobacco-attributed deaths (6 373), followed by lung cancer (4 923), ischaemic heart disease (4 216), tuberculosis (2 326) and lower respiratory infections (1 950). The distribution of major causes of smoking-attributable deaths shows a middle- to high-income pattern in whites and Asians, and a middle- to low-income pattern in coloureds and black Africans. The role of infectious lung disease (TB and LRIs) has been underappreciated. These diseases comprised 21.0% of deaths among black Africans compared with only 4.3% among whites. It is concerning that smoking rates have plateaued since 2010. Conclusion. The gains achieved in reducing smoking prevalence in SA have been eroded since 2010. An increase in excise taxes is the most effective measure for reducing smoking prevalence. The advent of serious respiratory pandemics such as COVID-19 has increased the urgency of considering the role that smoking cessation/abstinence can play in the prevention of, and post-hospital recovery from, any condition

TB epidemiology: where are the young women? Know your tuberculosis epidemic, know your response.

CAPRISA, 2018.Abstract available in pdf

Genetic Drivers of Heterogeneity in Type 2 Diabetes Pathophysiology

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P \u3c 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care

Emergence and spread of two SARS-CoV-2 variants of interest in Nigeria.

Identifying the dissemination patterns and impacts of a virus of economic or health importance during a pandemic is crucial, as it informs the public on policies for containment in order to reduce the spread of the virus. In this study, we integrated genomic and travel data to investigate the emergence and spread of the SARS-CoV-2 B.1.1.318 and B.1.525 (Eta) variants of interest in Nigeria and the wider Africa region. By integrating travel data and phylogeographic reconstructions, we find that these two variants that arose during the second wave in Nigeria emerged from within Africa, with the B.1.525 from Nigeria, and then spread to other parts of the world. Data from this study show how regional connectivity of Nigeria drove the spread of these variants of interest to surrounding countries and those connected by air-traffic. Our findings demonstrate the power of genomic analysis when combined with mobility and epidemiological data to identify the drivers of transmission, as bidirectional transmission within and between African nations are grossly underestimated as seen in our import risk index estimates

Genetic drivers of heterogeneity in type 2 diabetes pathophysiology

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P &lt; 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care.</p

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Nicotine delivery capabilities of smokeless tobacco products and implications for control of tobacco dependence in South Africa

Objectives: Smokeless tobacco (SLT) use is popular among black South African women and children. The study sought to determine the nicotine delivery capability of popular industrialised and traditional SLT brands in South Africa, and to provide information for policy action by regulatory authorities. Design: Laboratory chemical analysis of four industrialised and one traditional SLT products commercially available, using previously published analytical methods. Potential for dependence was inferred from nicotine delivery capabilities determined by the percentage free base nicotine. Measurements: Moisture, pH, total nicotine, and percentage free base nicotine. Results: Total nicotine content was between 6–16 mg/g. The pH varied between 7–10 and this correlated with percentage free base nicotine, which ranged between 10–99%. The nicotine delivery capability of the traditional product was lower than that of the industrialised products except for the recently introduced portion bag snus, which had comparable total nicotine but the lowest pH and percentage free base nicotine. The most popular SLT brands showed the highest percentage free base nicotine ever reported for any industrialised SLT or cigarette brands. Small cans contained higher nicotine than the large cans of the same brand tested. Findings from the study support a potential for limited "product graduation" by users. Conclusions: South African SLT users are mostly exposed to potentially very highly addictive levels of nicotine that may favour tobacco dependence and its consequent health risks. The increasing use of SLT by women of childbearing age support the need for intensified policy action to control its use