Multivitamin use and risk of stroke incidence and mortality amongst women.

BACKGROUND AND PURPOSE: Few studies have examined the association between multivitamin use and the risk of stroke incidence and mortality, and the results remain inconclusive as to whether multivitamins are beneficial. METHODS: The associations between multivitamin use and the risk of incident stroke and stroke mortality were prospectively examined in 86 142 women in the Nurses' Health Study, aged 34-59 years and free of diagnosed cardiovascular disease at baseline. Multivitamin use and covariates were updated every 2 years and strokes were documented by review of medical records. Hazard ratios of total, ischaemic and hemorrhagic strokes were calculated across categories of multivitamin use (non-user, past, current user) and duration (years), using Cox proportional hazards models. RESULTS: During 32 years of follow-up from 1980 to 2012, 3615 incident strokes were documented, including 758 deaths from stroke. In multivariate analyses, women who were current multivitamin users did not have a lower risk of incident total stroke compared to non-users [relative risk (RR) 1.02, 95% confidence interval (CI) 0.93-1.11], even those with longer durations of 15 or more years of use (RR 1.08, 95% CI 0.97-1.20) or those with a lower quality diet (RR 0.96, 95% CI 0.80-1.15). There was also no indication of benefit from multivitamin use for incident ischaemic or hemorrhagic strokes or for total stroke mortality. CONCLUSIONS: Long-term multivitamin use was not associated with reduced risk of stroke incidence or mortality amongst women in the study population, even amongst those with a lower diet quality. An effect in a less well-nourished population cannot be ruled out.

The burden of HPV associated cancers in two regions in Nigeria 2012-2014.

INTRODUCTION: HPV attributable cancers are the second most common infection-related cancers worldwide, with much higher burden in less developed regions. There are currently no country-specific estimates of the burden of these cancers in Nigeria just like many other low and middle income countries. METHODS: In this study, we quantified the proportion of the cancer burden in Nigeria that is attributable to HPV infection from 2012 to 2014 using HPV prevalence estimated from previous studies and data from two population based cancer registries (PBCR) in Nigeria. We considered cancer sites for which there is strong evidence of an association with HPV infection based on the International Agency for Research on Cancer (IARC) classification. We obtained age and sex-specific estimates of incident cancers and using the World Standard Population, we derived age standardized incidence (ASR) rates for each cancer type by categories of sex, and estimated the population attributable fractions (PAF). RESULTS: The two PBCR reported 4336 new cancer cases from 2012 to 2014. Of these, 1627 (37.5%) were in males and 2709 (62.5%) in females. Some 11% (488/4336) of these cancers were HPV associated; 2% (38/1627) in men and 17% (450/2709) in women. Of the HPV associated cancers, 7.8% occurred in men and 92.2% in women. The ASRs for HPV associated cancers was 33.5 per 100,000; 2.3 and 31.2 per 100,000 in men and women respectively. The proportion of all cancers attributable to HPV infection ranged from 10.2 to 10.4% (442-453 of 4336) while the proportion of HPV associated cancers attributable to HPV infection ranged from 90.6% to 92.8% (442-453 of the 488 cases). In men, 55.3% to 68.4% of HPV associated cancers were attributable to HPV infection compared to 93.6% to 94.8% in women. The combined ASR for HPV attributable cancers ranged from 31.0 to 31.7 per 100,000. This was 1.4 to 1.7 per 100,000 in men and 29.6 to 30.0 per 100,000 in women. In women, cervical cancer (n=392, ASR 28.3 per 100,000) was the commonest HPV attributable cancer, while anal cancer (n=21, ASR 1.2 per 100,000) was the commonest in men. CONCLUSIONS: HPV attributable cancers constitute a substantial cancer burden in Nigerian women, much less so in men. A significant proportion of cancers in Nigerian women would be prevented if strategies such as HPV DNA based screening and HPV vaccination are implemented.

Prevalent high-risk HPV infection and vaginal microbiota in Nigerian women.

In this study, we evaluated the association between high-risk human papillomavirus (hrHPV) and the vaginal microbiome. Participants were recruited in Nigeria between April and August 2012. Vaginal bacterial composition was characterized by deep sequencing of barcoded 16S rRNA gene fragments (V4) on Illumina MiSeq and HPV was identified using the Roche Linear Array® HPV genotyping test. We used exact logistic regression models to evaluate the association between community state types (CSTs) of vaginal microbiota and hrHPV infection, weighted UniFrac distances to compare the vaginal microbiota of individuals with prevalent hrHPV to those without prevalent hrHPV infection, and the Linear Discriminant Analysis effect size (LEfSe) algorithm to characterize bacteria associated with prevalent hrHPV infection. We observed four CSTs: CST IV-B with a low relative abundance of Lactobacillus spp. in 50% of participants; CST III (dominated by L. iners) in 39·2%; CST I (dominated by L. crispatus) in 7·9%; and CST VI (dominated by proteobacteria) in 2·9% of participants. LEfSe analysis suggested an association between prevalent hrHPV infection and a decreased abundance of Lactobacillus sp. with increased abundance of anaerobes particularly of the genera Prevotella and Leptotrichia in HIV-negative women (P < 0·05). These results are hypothesis generating and further studies are required.