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Crook A.M.,University College London | Ford D.,University College London | Gafos M.,University College London | Gafos M.,Africa Center for Health and Population Studies | And 8 more authors.
Human Reproduction | Year: 2014

study question: Do injectable and oral contraceptives increase the risk of human immunodeficiency virus (HIV) acquisition in women? summaryanswer: After adjusting for confounders, evidence of a significantly increased risk of HIV remained for women using injectable depo-medroxyprogesterone (DMPA) (hazard ratio = 1.49, 95% confidence interval (1.06-2.08)) but not for injectable norethisteroneenanthate (Net-En) or oral contraceptive pills (OC). what is known already: An association between the use of some types of hormonal contraception (HC) methods and an increased risk of HIV, possibly through changes in the genital tract environment and alterations in the immune response, has been previously observed, although not consistently. A recent systematic review of these studies has highlighted the need for more definitive evidence. study design, size, duration: A secondary data analysis of the MDP301 phase 3 microbicide trial was conducted to estimate the effects of use of different methods ofHCon the risk of HIV acquisition in women. HIV-negative women (n = 8663) with a median age of 28 years were included in the analysis; 382 HIV seroconverted by 52 weeks follow-up; 10% of women-years were lost to follow-up before 52 weeks. participants/materials, setting, methods: Contraceptive use was reported at each 4-weekly visit. Cox proportional hazards (PH) models were used to estimate the effects of baseline and current use of injectable DMPA, injectable Net-En and OC compared with no HC, on the risk of HIV, adjusting for baseline and time-updated covariates. Causal effects for 52 weeks of HC use compared with no HC were estimated in a weighted Cox model, censoring women at deviation from baseline HC use (or non-use) or pregnancy. main results and the role of chance: At baseline, 2499 (29%) women were on DMPA, 1180 (14%) on Net-En, and 1410 (16%) on OC; 3574 (40%) not on HC, started HC in follow-up. Adjusted hazard ratios (HR) for baseline HC use, compared with no HC, were 1.38 (95% confidence interval (CI) 1.07-1.78) for DMPA; 1.18 (0.86-1.62) for Net-En and 0.97 (0.68-1.38) for OC. The estimated causal effects of DMPA and Net-En over 52 weeks were: HR = 1.49 (95% CI 1.06-2.08) and HR = 1.31 (95% CI 0.62-1.61), respectively. limitations, reasons for caution: Amain limitation of the study wasthat it was a secondary analysis of datafrom a study thatwas not designed to investigate this question. Despite our best efforts, we cannot exclude residual confounding to explain the effect of DMPA. wider implications of the findings: The results of this study should be reviewed by theWorld Health Organization to determine whether current recommendations on the use of DMPA in settings with high HIV prevalence require modification. © The Author 2014.


Francis J.M.,London School of Hygiene and Tropical Medicine | Francis J.M.,National Institute for Medical Research | Weiss H.A.,London School of Hygiene and Tropical Medicine | Mshana G.,National Institute for Medical Research | And 7 more authors.
PLoS ONE | Year: 2015

Introduction Alcohol use is a global public health problem, including as a risk factor for HIV infection, but few data are available on the epidemiology of alcohol use and alcohol use disorders (AUD) among young people in sub-Saharan Africa. Methods We conducted a cross-sectional survey among 4 groups of young people aged 15â€"24 years old (secondary school students, college/university students, employees of local industries and casual labourers) in two regions (Kilimanjaro and Mwanza) of northern Tanzania. Using a multistage stratified random sampling strategy, we collected information on demographics, alcohol use, and behavioural factors. We screened severity of alcohol use using the Alcohol Use Disorder Identification Test (AUDIT) and estimated the quantity and frequency of alcohol consumption using the timeline-follow-back-calendar (TLFB) method. Results A total of 1954 young people were surveyed. The prevalence of reported alcohol use was higher among males (47â€"70% ever users and 20â€"45% current users) than females (24â€" 54% ever users and 12â€"47% current users). Prevalence of use was substantially higher in Kilimanjaro than Mwanza region. In both regions, participants reported high exposure to alcohol advertisements, and wide alcohol availability. College students reported the highest prevalence of current alcohol use (45% among males; 26% among females) and of heavy episodic drinking (71% among males; 27% among females) followed by casual labourers. Males were more likely to have AUD (an AUDIT score 8) than females, with 11â€"28% of males screening positive for AUD. Alcohol use was associated with male gender, being in a relationship, greater disposable income, non-Muslim religion and a higher number of sexual partners. Conclusions Alcohol use is a significant problem among young people in northern Tanzania. There is an urgent need to develop, pilot and deliver interventions to help young people delay initiation and reduce levels of harmful drinking, particularly among college students and casual labourers. © 2015 Francis et al.


Francis J.M.,London School of Hygiene and Tropical Medicine | Francis J.M.,National Institute for Medical Research | Weiss H.A.,London School of Hygiene and Tropical Medicine | Helander A.,Karolinska Institutet | And 7 more authors.
Drug and Alcohol Dependence | Year: 2015

Background: The one-month Time Line Follow Back calendar (TLFB) and the Alcohol Use Disorders Identification Test (AUDIT) are used to collect self-reported alcohol intake data. We compared these instruments with the alcohol biomarker phosphatidylethanol (PEth) among young-people in northern Tanzania. Methods: AUDIT and TLFB were applied in a cross-sectional study of 202 young people (18-24 years), who reported using alcohol during the past year (103 male casual labourers; 99 college students). We assayed whole blood for PEth 16:0/18:1, using liquid chromatography-tandem mass spectrometry. Results: For both self-report methods, alcohol consumption was high, particularly among men (e.g. a median of 54 drinks per month in labourers), and about half of male students (48%) reported hazardous or harmful levels of drinking (AUDIT ≥8). Almost half (49%) of participants were PEth-positive (median concentration 0.03μmol/L). There were significant positive correlations between reported total alcohol intake and PEth concentration in males (Spearman's correlation rs=0.65 in college students and rs=0.57 in casual labourers; p<0.001). Self-reported use in the past month was a sensitive marker of having a positive PEth result (≥0.01μmol/L) with 89% of those with a PEth positive result reporting alcohol use, and this was similar in all groups. The proportion of those with AUDIT scores ≥8 and AUDIT-C scores ≥6 among those with a high cut-off positive PEth result (≥0.30μmol/L) ranged between 94 and 100%. Conclusion: TLFB and AUDIT are sensitive measures to detect heavy alcohol use among young-people in northern Tanzania. They can be used to identify young people who may benefit from alcohol-focused interventions. © 2015 The Authors.


Francis J.M.,London School of Hygiene and Tropical Medicine | Francis J.M.,National Institute for Medical Research | Helander A.,Karolinska Institutet | Kapiga S.H.,London School of Hygiene and Tropical Medicine | And 6 more authors.
International Journal of Environmental Research and Public Health | Year: 2015

The alcohol dependence section of the Mini International Neuropsychiatric Interview questionnaire (MINI) has not been evaluated in young Africans. We applied the MINI in a cross-sectional study of 202 alcohol users from northern-Tanzania, aged 18–24 years (103 male casual workers and 99 students), and validated it against phophatidylethanol (PEth) at a cut-off suggesting heavy chronic alcohol use (≥0.30 μmol/L). Blood was assayed for PEth (16:0/18:1-subform) by liquid chromatography-tandem mass spectrometry. The MINI dependence criteria (≥3 positive responses) were met by 39% participants although their PEth levels were low. Contrary, many young people with high PEth levels were not classified as dependent. The sensitivity of the MINI ranged from 0% to 69% (female students and male workers, respectively) and specificity from 52% to 85% (workers and female students, respectively). The highest AUROC (0.68) occurred with a cut-off of ≥4 positive responses. A modified MINI with three affirmative responses to five questions increased specificity to 92%–97%; however, sensitivity remained low. The performance of the MINI in detecting dependence among young people from northern-Tanzania is unsatisfactory. Specificity was improved using a modified version but sensitivity remained low. An accurate tool for the diagnosis of alcohol dependence is needed for epidemiological and clinical purposes. © 2015 by the authors; licensee MDPI, Basel, Switzerland.

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