Smoking as a weight-control strategy among adolescent girls and young women: a reconsideration

Many studies have reported that adolescent girls and young women smoke to control their weight. The majority of these studies are cross-sectional and report on correlational data from quantitative surveys. This article presents data from ethnographic interviews with 60 smokers, interviewed in high school and in follow-up interviews at age 21. Contrary to previous research, this study found little evidence for the sustained use of smoking as a weight-control strategy. In high school, smokers were no more likely than nonsmokers to be trying to lose weight. In the follow-up study, 85 percent of informants replied that they had never smoked as a way to control their weight. One-half of informants at age 21 believed that smoking as a weight-control strategy would be ineffective, while the other one-half had no idea whether it would work or not. Researchers need to exert caution in propagating the idea that smoking is commonly used as a conscious and sustained weight-control strategy among adolescent females and young women.     

Cancer risk among young men with weight gain after smoking cessation: A population-based cohort study

BackgroundSmoking cessation may help the current smokers to reduce cancer risk. However, weight gain following smoking cessation may attenuate the protective association of cessation with cancer.Patients and methodsOur study included 1,278,794 men who were aged 20–39 years and underwent two consecutive health examinations by the National Health Insurance Service, without previous diagnosis of cancer. Participants were categorized into continual smokers, quitters with different degree of body weight change, and never smokers based on the biennial national health screening program (2002–2003 and 2004–2005) and were followed from January 1, 2006 to December 31, 2015. Cox proportional hazard models and restricted cubic spline model was used to evaluate the association of post-cessation weight change and cancer risk after adjustment for potential confounders.ResultsDuring the 10 years of follow-up, the analyses included 1,278,794 men with 21,494 cancer incidences. Compared to continual smokers, quitters without weight gain of 2.0 kg had significantly lower risk of obesity-related cancer (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.79-0.97), smoking-related cancer (HR, 0.90; 95% CI, 0.83 to 0.98), and gastrointestinal cancer (HR, 89; 95% CI, 0.80 to 0.98). Weight gain among quitters attenuated the risk reduction of cancer compared to continual smoking. Among quitters, weight gain up to 5.0 kg with smoking cessation showed protective association with cancer risk among quitters without weight gain.ConclusionExcessive weight gain with smoking cessation among quitters was not associated with reduced risk of several cancer types. This association should be taken into account when recommending smoking cessation to prevent cancer     

Cancer incidence among Canadian Veterans: A matched cohort study

IntroductionOccupational exposures related to military service may increase the risk of cancer for military Veterans, while high levels of fitness during service may decrease risk. However, few studies have compared this post-career cancer risk directly to the employed general population.MethodsThis retrospective cohort study used linked administrative data. Canadian Armed Forces and Royal Canadian Mounted Police Veterans in Ontario, Canada were matched 1:4 on age, sex, geography, and community-level income to a group of non-Veterans most likely to have been employed during a period similar to the Veterans’ military service. Cancer diagnoses were identified using the Ontario Cancer Registry.ResultsDuring the study period, 642 of 30 576 included Veterans (2.1%) and 3408 of the 122 293 matched general population cohort (2.8%) experienced at least one cancer diagnosis. The crude rate of cancer was 153.5 per 100 000 person-years among Veterans vs. 205.9 per 100 000 person-years for the general population cohort. After adjusting for rurality and matching variables, Veterans had an 27% lower risk of developing any cancer than their matched comparators [hazard ratio = 0.73 (95% CI: 0.67–0.80)]. Among specific cancer types, the risk of lung and colorectal cancer was significantly lower for Veterans relative to the general population cohort; the risk of breast and prostate cancer was similar.DiscussionThis study adds to the growing international evidence suggesting that risk of many cancers among Veterans is lower or similar to the general population. Further understanding of the complex relationships among occupational exposures, environmental factors, and lifestyle factors is needed.     

A prospective cohort study of physical activity in relation to lung cancer incidence among Black women

BackgroundBlack women have higher lung cancer incidence and mortality rates despite a lower smoking prevalence than White women. Physical activity may reduce lung cancer risk through several pathways, including the immune and inflammatory systems, as well as those with effects on sex hormones and metabolism.MethodsWe examined vigorous physical activity, walking for exercise, sitting watching television, and metabolic equivalents (METs) in relation to lung cancer risk among 38,432 participants in a prospective cohort of Black women. We used Cox proportional hazards models adjusted for covariates to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).ResultsIn 1995–2017, 475 incident lung cancer cases accrued. Participants who engaged in ≥ 1 h/week of vigorous physical activity or expended the highest tertile of METs experienced a decreased risk of lung cancer (HR: 0.85, 95% CI: 0.65–1.10; 0.89, 0.68–1.18; respectively). An increased risk was observed for sitting watching television (≥1 h/week: 1.27, 0.72–2.21). In stratified models, an inverse association between walking for exercise and lung cancer risk was only present among former smokers (≥1 h/week: 0.71, 0.52–0.98), while inverse associations between vigorous physical activity (≥1 h/week: 0.45, 0.28–0.73) and METs (tertile 3: 0.54, 0.34–0.85) and lung cancer risk were present among smokers with ≥ 20 pack-years.ConclusionPhysical activity may play a role in reducing lung cancer risk among Black women, particularly among smokers. Future studies should explore biologic mechanisms whereby physical activity may influence carcinogenesis and investigate the role of exercise interventions in reducing lung cancer risk among smokers.     

The genetic analysis of hyperandrogenism of different origins in adolescent girls and young women]

The pedigrees of 192 girls aged 14.19 with different forms of hyperandrogenism (HA) have been studied. The hirsutism has been taken as a main symptom in analysis of pedigrees. The verification of different models of HA inheritance allows considering HA to be a multifactorial disease which is inherited as a quasi-alternative model. The coefficient of heritability is equal to 0.65-1.0.     

Variation in HIV care and treatment outcomes by facility in South Africa, 2011–2015: A cohort study

BackgroundDespite widespread availability of HIV treatment, patient outcomes differ across facilities. We propose and evaluate an approach to measure quality of HIV care at health facilities in South Africa’s national HIV program using routine laboratory data.Methods and findingsData were extracted from South Africa’s National Health Laboratory Service (NHLS) Corporate Data Warehouse. All CD4 counts, viral loads (VLs), and other laboratory tests used in HIV monitoring were linked, creating a validated patient identifier. We constructed longitudinal HIV care cascades for all patients in the national HIV program, excluding data from the Western Cape and very small facilities. We then estimated for each facility in each year (2011 to 2015) the following cascade measures identified a priori as reflecting quality of HIV care: median CD4 count among new patients; retention 12 months after presentation; 12-month retention among patients established in care; viral suppression; CD4 recovery; monitoring after an elevated VL. We used factor analysis to identify an underlying measure of quality of care, and we assessed the persistence of this quality measure over time. We then assessed spatiotemporal variation and facility and population predictors in a multivariable regression context.We analyzed data on 3,265 facilities with a median (IQR) annual size of 441 (189 to 988) lab-monitored HIV patients. Retention 12 months after presentation increased from 42% to 47% during the study period, and viral suppression increased from 66% to 79%, although there was substantial variability across facilities. We identified an underlying measure of quality of HIV care that correlated with all cascade measures except median CD4 count at presentation. Averaging across the 5 years of data, this quality score attained a reliability of 0.84. Quality was higher for clinics (versus hospitals), in rural (versus urban) areas, and for larger facilities. Quality was lower in high-poverty areas but was not independently associated with percent Black. Quality increased by 0.49 (95% CI 0.46 to 0.53) standard deviations from 2011 to 2015, and there was evidence of geospatial autocorrelation (p < 0.001). The study’s limitations include an inability to fully adjust for underlying patient risk, reliance on laboratory data which do not capture all relevant domains of quality, potential for errors in record linkage, and the omission of Western Cape.ConclusionsWe observed persistent differences in HIV care and treatment outcomes across South African facilities. Targeting low-performing facilities for additional support could reduce overall burden of disease.

Jacob Bor and co-workers use a new measure of care quality to report on facility-level variations in HIV care and outcomes in South Africa.     

Pregnancy incidence and correlates during the HVTN 503 Phambili HIV vaccine trial conducted among South African women

Background

HIV prevention trials are increasingly being conducted in sub-Saharan Africa. Women at risk for HIV are also at risk of pregnancy. To maximize safety, women agree to avoid pregnancy during trials, yet pregnancies occur. Using data from the HVTN 503/“Phambili” vaccine trial, we report pregnancy incidence during and after the vaccination period and identify factors, measured at screening, associated with incident pregnancy.

Methods

To enrol in the trial, women agreed and were supported to avoid pregnancy until 1 month after their third and final vaccination (“vaccination period”), corresponding to the first 7 months of follow-up. Unsterilized women, pooled across study arms, were analyzed. Poisson regression compared pregnancy rates during and after the vaccination period. Cox proportional hazards regression identified associations with first pregnancy.

Results

Among 352 women (median age 23 yrs; median follow-up 1.5 yrs), pregnancy incidence was 9.6/100 women-years overall and 6.8/100 w-yrs and 11.3/100 w-yrs during and after the vaccination period, respectively [Rate Ratio = 0.60 (0.32–1.14), p = 0.10]. In multivariable analysis, pregnancy was reduced among women who: enrolled at sites providing contraception on-site [HR = 0.43, 95% CI (0.22–0.86)]; entered the trial as injectable contraceptive users [HR = 0.37 (0.21–0.67)] or as consistent condom users (trend) [HR = 0.54 (0.28–1.04)]. Compared with women with a single partner of HIV-unknown status, pregnancy rates were increased among women with: a single partner whose status was HIV-negative [HR = 2.34(1.16–4.73)] and; 2 partners both of HIV-unknown status [HR = 4.42(1.59–12.29)]. Women with 2 more of these risk factors: marijuana use, heavy drinking, or use of either during sex, had increased pregnancy incidence [HR = 2.66 (1.24–5.72)].

Conclusions

It is possible to screen South African women for pregnancy risk at trial entry. Providing injectable contraception for free on-site and supporting consistent condom use may reduce incident pregnancy. Screening should determine the substance use, partnering, and HIV status of both members of the couple for both pregnancy and HIV prevention.

Trial Registration

SA National Health Research Database DOH-27-0207-1539; Clinicaltrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00413725","term_id":"NCT00413725"}}NCT00413725     

Childhood leukemia mortality and farming exposure in South Korea: A national population-based birth cohort study

ObjectivesThe aim of this study was to evaluate the relationship between leukemia mortality and exposure to farming among children in South Korea.MethodsA retrospective cohort study of South Korean children was conducted using data collected by the national birth register between 1995 and 2006; these data were then individually linked to death data. A cohort of 6,479,406 children was followed from birth until either their death or until December 31, 2006. For surrogate measures of pesticide exposure, we used residence at birth, paternal occupation, and month of conception from the birth certificate. Farming and pesticide exposure indexes by county were calculated using information derived from the 2000 agricultural census. Poisson regression analyses were used to calculate rate ratios (RRs) of childhood leukemia deaths according to indices of exposure to agricultural pesticides after adjustment for potential confounders.ResultsIn total 585 leukemia deaths were observed during the study period. Childhood leukemia mortality was significantly elevated in children born in rural areas (RR = 1.43, 95%CI 1.09–1.86) compared to those in metropolises, and in counties with both the highest farming index (RR = 1.33, 95%CI 1.04–1.69) and pesticide exposure index (RR = 1.30, 95%CI 1.02–1.66) compared to those in the reference group. However, exposure–response associations were significant only in relation to the farming index. When the analyses were limited to rural areas, the risk of death from leukemia among boys conceived between spring and fall increased over those conceived in winter.ConclusionsOur results show an increase in mortality from childhood leukemia in rural areas; however, further studies are warranted to investigate the environmental factors contributing to the excess mortality from childhood leukemia in rural areas.     

High incidence of unplanned pregnancy after antiretroviral therapy initiation: findings from a prospective cohort study in South Africa

Background

Increased fertility rates in HIV-infected women receiving antiretroviral therapy (ART) have been attributed to improved immunological function; it is unknown to what extent the rise in pregnancy rates is due to unintended pregnancies.

Methods

Non-pregnant women ages 18–35 from four public-sector ART clinics in Johannesburg, South Africa, were enrolled into a prospective cohort and followed from August 2009–March 2011. Fertility intentions, contraception and pregnancy status were measured longitudinally at participants'' routine ART clinic visits.

Findings

Of the 850 women enrolled, 822 (97%) had at least one follow-up visit and contributed 745.2 person-years (PY) at-risk for incident pregnancy. Overall, 170 pregnancies were detected in 161 women (incidence rate [IR]: 21.6/100 PY [95% confidence interval (CI): 18.5–25.2]). Of the 170 pregnancies, 105 (62%) were unplanned. Unmet need for contraception was 50% higher in women initiating ART in the past year as compared to women on ART>1 year (prevalence ratio 1.5 [95% CI: 1.1–2.0]); by two years post-ART initiation, nearly one quarter of women had at least one unplanned pregnancy. Cumulative incidence of pregnancy was equally high among recent ART initiators and ART experienced participants: 23.9% [95% CI: 16.4–34.1], 15.9% [12.0–20.8], and 21.0% [16.8–26.1] for women on ART 0–1 yr, >1 yr–2 yrs, and >2 yrs respectively (log-rank, p = 0.54). Eight hormonal contraceptive failures were detected [IR: 4.4 [95% CI: 2.2–8.9], 7/8 among women using injectable methods. Overall 47% (80/170) of pregnancies were not carried to term.

Conclusions

Rates of unintended pregnancies among women on ART are high, including women recently initiating ART with lower CD4 counts and higher viral loads. A substantial burden of pregnancy loss was observed. Integration of contraceptive services and counselling into ART care is necessary to reduce maternal and child health risks related to mistimed and unwanted pregnancies. Further research into injectable contraceptive failures on ART is warranted.     

Estimating HIV incidence among adults in Kenya and Uganda: a systematic comparison of multiple methods

Background

Several approaches have been used for measuring HIV incidence in large areas, yet each presents specific challenges in incidence estimation.

Methodology/Principal Findings

We present a comparison of incidence estimates for Kenya and Uganda using multiple methods: 1) Epidemic Projections Package (EPP) and Spectrum models fitted to HIV prevalence from antenatal clinics (ANC) and national population-based surveys (NPS) in Kenya (2003, 2007) and Uganda (2004/2005); 2) a survey-derived model to infer age-specific incidence between two sequential NPS; 3) an assay-derived measurement in NPS using the BED IgG capture enzyme immunoassay, adjusted for misclassification using a locally derived false-recent rate (FRR) for the assay; (4) community cohorts in Uganda; (5) prevalence trends in young ANC attendees. EPP/Spectrum-derived and survey-derived modeled estimates were similar: 0.67 [uncertainty range: 0.60, 0.74] and 0.6 [confidence interval: (CI) 0.4, 0.9], respectively, for Uganda (2005) and 0.72 [uncertainty range: 0.70, 0.74] and 0.7 [CI 0.3, 1.1], respectively, for Kenya (2007). Using a local FRR, assay-derived incidence estimates were 0.3 [CI 0.0, 0.9] for Uganda (2004/2005) and 0.6 [CI 0, 1.3] for Kenya (2007). Incidence trends were similar for all methods for both Uganda and Kenya.

Conclusions/Significance

Triangulation of methods is recommended to determine best-supported estimates of incidence to guide programs. Assay-derived incidence estimates are sensitive to the level of the assay''s FRR, and uncertainty around high FRRs can significantly impact the validity of the estimate. Systematic evaluations of new and existing incidence assays are needed to the study the level, distribution, and determinants of the FRR to guide whether incidence assays can produce reliable estimates of national HIV incidence.     

Diagnostic accuracy of cervical cancer screening and screening–triage strategies among women living with HIV-1 in Burkina Faso and South Africa: A cohort study

BackgroundCervical cancer screening strategies using visual inspection or cytology may have suboptimal diagnostic accuracy for detection of precancer in women living with HIV (WLHIV). The optimal screen and screen–triage strategy, age to initiate, and frequency of screening for WLHIV remain unclear. This study evaluated the sensitivity, specificity, and positive predictive value of different cervical cancer strategies in WLHIV in Africa.Methods and findingsWLHIV aged 25–50 years attending HIV treatment centres in Burkina Faso (BF) and South Africa (SA) from 5 December 2011 to 30 October 2012 were enrolled in a prospective evaluation study of visual inspection using acetic acid (VIA) or visual inspection using Lugol’s iodine (VILI), high-risk human papillomavirus DNA test (Hybrid Capture 2 [HC2] or careHPV), and cytology for histology-verified high-grade cervical intraepithelial neoplasia (CIN2+/CIN3+) at baseline and endline, a median 16 months later. Among 1,238 women (BF: 615; SA: 623), median age was 36 and 34 years (p < 0.001), 28.6% and 49.6% ever had prior cervical cancer screening (p < 0.001), and 69.9% and 64.2% were taking ART at enrolment (p = 0.045) in BF and SA, respectively. CIN2+ prevalence was 5.8% and 22.4% in BF and SA (p < 0.001), respectively. VIA had low sensitivity for CIN2+ (44.7%, 95% confidence interval [CI] 36.9%–52.7%) and CIN3+ (56.1%, 95% CI 43.3%–68.3%) in both countries, with specificity for ≤CIN1 of 78.7% (95% CI 76.0%–81.3%). HC2 had sensitivity of 88.8% (95% CI 82.9%–93.2%) for CIN2+ and 86.4% (95% CI 75.7%–93.6%) for CIN3+. Specificity for ≤CIN1 was 55.4% (95% CI 52.2%–58.6%), and screen positivity was 51.3%. Specificity was higher with a restricted genotype (HPV16/18/31/33/35/45/52/58) approach (73.5%, 95% CI 70.6%–76.2%), with lower screen positivity (33.7%), although there was lower sensitivity for CIN3+ (77.3%, 95% CI 65.3%–86.7%). In BF, HC2 was more sensitive for CIN2+/CIN3+ compared to VIA/VILI (relative sensitivity for CIN2+ = 1.72, 95% CI 1.28–2.32; CIN3+: 1.18, 95% CI 0.94–1.49). Triage of HC2-positive women with VIA/VILI reduced the number of colposcopy referrals, but with loss in sensitivity for CIN2+ (58.1%) but not for CIN3+ (84.6%). In SA, cytology high-grade squamous intraepithelial lesion or greater (HSIL+) had best combination of sensitivity (CIN2+: 70.1%, 95% CI 61.3%–77.9%; CIN3+: 80.8%, 95% CI 67.5%–90.4%) and specificity (81.6%, 95% CI 77.6%–85.1%). HC2 had similar sensitivity for CIN3+ (83.0%, 95% CI 70.2%–91.9%) but lower specificity compared to HSIL+ (42.7%, 95% CI 38.4%–47.1%; relative specificity = 0.57, 95% CI 0.52–0.63), resulting in almost twice as many referrals. Compared to HC2, triage of HC2-positive women with HSIL+ resulted in a 40% reduction in colposcopy referrals but was associated with some loss in sensitivity. CIN2+ incidence over a median 16 months was highest among VIA baseline screen-negative women (2.2%, 95% CI 1.3%–3.7%) and women who were baseline double-negative with HC2 and VIA (2.1%, 95% CI 1.3%–3.5%) and lowest among HC2 baseline screen-negative women (0.5%, 95% CI 0.1%–1.8%). Limitations of our study are that WLHIV included in the study may not reflect a contemporary cohort of WLHIV initiating ART in the universal ART era and that we did not evaluate HPV tests available in study settings today.ConclusionsIn this cohort study among WLHIV in Africa, a human papillomavirus (HPV) test targeting 14 high-risk (HR) types had higher sensitivity to detect CIN2+ compared to visual inspection but had low specificity, although a restricted genotype approach targeting 8 HR types decreased the number of unnecessary colposcopy referrals. Cytology HSIL+ had optimal performance for CIN2+/CIN3+ detection in SA. Triage of HPV-positive women with HSIL+ maintained high specificity but with some loss in sensitivity compared to HC2 alone.

In this cohort study, Helen Kelly and colleagues explore cervical cancer screening strategies for women living with HIV.     

Coerced first sexual intercourse and selected reproductive health outcomes among young women in KwaZulu-Natal, South Africa

Coercion may play an important role in compelling young women to engage in sexual intercourse at an early age. With a decline in age at first intercourse and increased reporting of coercive first sex, concerns of adverse reproductive health outcomes such as unintended pregnancy and sexually transmitted infections (STIs), including HIV, have become important issues, particularly in the context of a high HIV prevalence. This paper uses data collected in 2001 from the second round of a longitudinal study of 1130 sexually experienced young women in KwaZulu-Natal to investigate the relationship between coerced first intercourse and selected reproductive health outcomes and behaviours. Nearly 46% of all sexually experienced young women had reported that their first sexual encounter had been coerced. Young women who reported being coerced at first sex were significantly more likely to be Black and living in an urban area. Those who had been coerced at first sex were also more likely to report having had an STI and having experienced unintended pregnancy, than those who had not been coerced at first sex. Coercion at first sex is an important social and public health problem that has a serious impact on the reproductive health and behaviours of young women. Interventions should directly address the issue of sexual coercion by ensuring young women are aware of their reproductive rights.     

HIV incidence remains high in KwaZulu-Natal, South Africa: evidence from three districts

Background

HIV prevalence and incidence among sexually active women in peri-urban areas of Ladysmith, Edendale, and Pinetown, KwaZulu-Natal, South Africa, were assessed between October 2007 and February 2010 in preparation for vaginal microbicide trials.

Methodology/Principal Findings

Sexually active women 18–35 years, not known to be HIV-positive or pregnant were tested cross-sectionally to determine HIV and pregnancy prevalence (798 in Ladysmith, 1,084 in Edendale, and 891 in Pinetown). Out of these, approximately 300 confirmed non-pregnant, HIV-negative women were subsequently enrolled at each clinical research center (CRC) in a 12-month cohort study with quarterly study visits. Women in the cohort studies were required to use a condom plus a hormonal contraceptive method. HIV prevalence rates in the baseline cross-sectional surveys were high: 42% in Ladysmith, 46% in Edendale and 41% in Pinetown. Around 90% of study participants at each CRC reported one sex partner in the last 3 months, but only 14–30% stated that they were sure that none of their sex partners were HIV-positive. HIV incidence rates based on seroconversions over 12 months were 14.8/100 person-years (PY) (95% CI 9.7, 19.8) in Ladysmith, 6.3/100 PY (95% CI 3.2, 9.4) in Edendale, and 7.2/100 PY (95% CI 3.7, 10.7) in Pinetown. The 12-month pregnancy incidence rates (in the context of high reported contraceptive use) were: 5.7/100 PY (95% CI 2.6, 8.7) in Ladysmith, 3.1/100 PY (95% CI 0.9, 5.2) in Edendale and 6.3/100 PY (95% CI 3.0, 9.6) in Pinetown.

Conclusions/Significance

HIV prevalence and incidence remain high in peri-urban areas of KwaZulu-Natal.     

HIV prevalence and incidence among sexually active females in two districts of South Africa to determine microbicide trial feasibility

Background

The suitability of populations of sexually active women in Madibeng (North-West Province) and Mbekweni (Western Cape), South Africa, for a Phase III vaginal microbicide trial was evaluated.

Methods

Sexually active women 18–35 years not known to be HIV-positive or pregnant were tested cross-sectionally to determine HIV and pregnancy prevalence (798 in Madibeng and 800 in Mbekweni). Out of these, 299 non-pregnant, HIV-negative women were subsequently enrolled at each clinical research center in a 12-month cohort study with quarterly study visits.

Results

HIV prevalence was 24% in Madibeng and 22% in Mbekweni. HIV incidence rates based on seroconversions over 12 months were 6.0/100 person-years (PY) (95% CI 3.0, 9.0) in Madibeng and 4.5/100 PY (95% CI 1.8, 7.1) in Mbekweni and those estimated by cross-sectional BED testing were 7.1/100 PY (95% CI 2.8, 11.3) in Madibeng and 5.8/100 PY (95% CI 2.0, 9.6) in Mbekweni. The 12-month pregnancy incidence rates were 4.8/100 PY (95% CI 2.2, 7.5) in Madibeng and 7.0/100 PY (95% CI 3.7, 10.3) in Mbekweni; rates decreased over time in both districts. Genital symptoms were reported very frequently, with an incidence of 46.8/100 PY (95% CI 38.5, 55.2) in Madibeng and 21.5/100 PY (95% CI 15.8, 27.3) in Mbekweni. Almost all (>99%) participants said that they would be willing to participate in a microbicide trial.

Conclusion

These populations might be suitable for Phase III microbicide trials provided that HIV incidence rates over time remain sufficiently high to support endpoint-driven trials.     

Mortality and incidence of new primary cancers in men with prostate cancer: A Danish population-based cohort study

Background: Prostate cancer (PC) survivors may have an increased risk of new primary cancers (NPCs) due to shared risk factors or PC-directed treatments. Methods: Using Danish registries, we conducted a cohort study of men with (n = 30,220) and without PC (n = 151,100) (comparators), matched 1:5 on age and PC diagnosis/index date. We computed incidence rates of NPCs per 10,000 person years (PY) and associated 95% confidence intervals (CI), and used Cox proportional hazards regression to compute hazard ratios (HRs) and 95%CI, adjusting for comorbidities. In order to obviate any impact of shorter survival among prostate cancer patients, we censored comparator patients when the matched prostate cancer patient died or was censored. Results: Follow-up spanned 113,487 PY and 462,982 PY in the PC and comparison cohorts, respectively. 65% of the cohorts were aged >70 years at diagnosis. Among PC patients, 51% had distant/unspecified stage, and 63% had surgery as primary treatment. The PC cohort had lower incidence of NPCs than their comparators. The adjusted HR of NPC among men with PC versus the comparators was 0.84 (95%CI = 0.80, 0.88). Lowest HRs were among older men, those with distant stage, and were particularly evident for cancers of the brain, liver, pancreas, respiratory, upper gastrointestinal, and urinary systems. Conclusions: We find no evidence of an increased risk of NPCs among men with PC. The deficit of NPCs among men with PC may be a true effect but is more likely due to lower levels of risk factors (e.g., smoking) in PC patients versus comparators, clinical consideration of cancers at new organs as metastases rather than new primaries, or under-recording/under-reporting of NPCs among PC patients.     

HIV prevention in high-risk women in South Africa: condom use and the need for change

Introduction

Young women are at disproportionate risk of HIV infection in South Africa. Understanding risk behaviors and factors associated with ability to negotiate safe sex and condom use is likely to be key in curbing the spread of HIV. Traditionally prevention efforts have focused on creating behavioral changes by increasing knowledge about HIV/AIDS.

Methods

This was a cross-sectional analysis from a prospective observational cohort study of 245 women at a high-risk of HIV infection in KwaZulu-Natal, South Africa.

Results

Participants demonstrated a high level of HIV/AIDS knowledge. Overall, 60.3% of participants reported condom use. Reported condom use at last sexual encounter varied slightly by partner type (57.0% with steady versus 64.4% with casual partners), and self-perceived ability to choose to use a condom was significantly lower with steady partners compared to casual partners (p<0.01). In multivariate analysis, women who had high school education were more likely to use condoms at their last sex encounter compared to those with only primary school education (RR of 1.36 (95% Confidence Interval (CI) 1.06–1.75) and 1.46 (95% CI 1.13–1.88) for grades 8–10 and 11–12, respectively). Those who used condoms as a contraceptive method were twice as likely to use condoms compared to women who did not report using them as a contraceptive method. Greater perceived ability to choose to use condoms was associated with higher self-reported condom use at last encounter, irrespective of partner type (RR = 2.65 (95% CI 2.15–32.5).

Discussion

Self-perceived ability to use condoms, level of formal education and condom use as a contraceptive were all significantly associated with self-reported condom use at last sexual encounter. These findings suggest that that gender inequality and access to formal education, as opposed to lack of HIV/AIDS knowledge, prevent safer sexual practices in South Africa.     

Learning that circumcision is protective against HIV: risk compensation among men and women in Cape Town, South Africa

Objectives

We examined whether knowledge of the HIV-protective benefits of male circumcision (MC) led to risk compensating behavior in a traditionally circumcising population in South Africa. We extend the current literature by examining risk compensation among women, which has hitherto been unexplored.

Methods

We used data on Xhosa men and women from the 2009 Cape Area Panel Study. Respondents were asked if they had heard that MC reduces a man’s risk of contracting HIV, about their perceived risk of contracting HIV, and condom use. For each gender group we assessed whether risk perception and condom use differed by knowledge of the protective benefits of MC using bivariate and then multivariate models controlling for demographic characteristics, HIV knowledge/beliefs, and previous sexual behaviors. In a further check for confounding, we used data from the 2005 wave to assess whether individuals who would eventually become informed about the protective benefits of circumcision were already different in terms of HIV risk perception and condom use.

Results

34% of men (n = 453) and 27% of women (n = 690) had heard that circumcision reduces a man’s risk of HIV infection. Informed men perceived slightly higher risk of contracting HIV and were more likely to use condoms at last sex (p<0.10). Informed women perceived lower HIV risk (p<0.05), were less likely to use condoms both at last sex (p<0.10) and more generally (p<0.01), and more likely to forego condoms with partners of positive or unknown serostatus (p<0.01). The results were robust to covariate adjustment, excluding people living with HIV, and accounting for risk perceptions and condom use in 2005.

Conclusions

We find evidence consistent with risk compensation among women but not men. Further attention should be paid to the role of new information regarding MC, and drivers of HIV risk more broadly, in modulating sexual behavior among women.