Relationships between intensity, duration, cumulative dose, and timing of smoking with age at menopause: A pooled analysis of individual data from 17 observational studies

BACKGROUND: Cigarette smoking is associated with earlier menopause, but the impact of being a former smoker and any dose-response relationships on the degree of smoking and age at menopause have been less clear. If the toxic impact of cigarette smoking on ovarian function is irreversible, we hypothesized that even former smokers might experience earlier menopause, and variations in intensity, duration, cumulative dose, and age at start/quit of smoking might have varying impacts on the risk of experiencing earlier menopause. METHODS AND FINDINGS: A total of 207,231 and 27,580 postmenopausal women were included in the cross-sectional and prospective analyses, respectively. They were from 17 studies in 7 countries (Australia, Denmark, France, Japan, Sweden, United Kingdom, United States) that contributed data to the International collaboration for a Life course Approach to reproductive health and Chronic disease Events (InterLACE). Information on smoking status, cigarettes smoked per day (intensity), smoking duration, pack-years (cumulative dose), age started, and years since quitting smoking was collected at baseline. We used multinomial logistic regression models to estimate multivariable relative risk ratios (RRRs) and 95% confidence intervals (CIs) for the associations between each smoking measure and categorised age at menopause ( \u3c 40 (premature), 40-44 (early), 45-49, 50-51 (reference), and \u3e /=52 years). The association with current and former smokers was analysed separately. Sensitivity analyses and two-step meta-analyses were also conducted to test the results. The Bayesian information criterion (BIC) was used to compare the fit of the models of smoking measures. Overall, 1.9% and 7.3% of women experienced premature and early menopause, respectively. Compared with never smokers, current smokers had around twice the risk of experiencing premature (RRR 2.05; 95% CI 1.73-2.44) (p \u3c 0.001) and early menopause (1.80; 1.66-1.95) (p \u3c 0.001). The corresponding RRRs in former smokers were attenuated to 1.13 (1.04-1.23; p = 0.006) and 1.15 (1.05-1.27; p = 0.005). In both current and former smokers, dose-response relationships were observed, i.e., higher intensity, longer duration, higher cumulative dose, earlier age at start smoking, and shorter time since quitting smoking were significantly associated with higher risk of premature and early menopause, as well as earlier menopause at 45-49 years. Duration of smoking was a strong predictor of age at natural menopause. Among current smokers with duration of 15-20 years, the risk was markedly higher for premature (15.58; 11.29-19.86; p \u3c 0.001) and early (6.55; 5.04-8.52; p \u3c 0.001) menopause. Also, current smokers with 11-15 pack-years had over 4-fold (4.35; 2.78-5.92; p \u3c 0.001) and 3-fold (3.01; 2.15-4.21; p \u3c 0.001) risk of premature and early menopause, respectively. Smokers who had quit smoking for more than 10 years had similar risk as never smokers (1.04; 0.98-1.10; p = 0.176). A limitation of the study is the measurement errors that may have arisen due to recall bias. CONCLUSIONS: The probability of earlier menopause is positively associated with intensity, duration, cumulative dose, and earlier initiation of smoking. Smoking duration is a much stronger predictor of premature and early menopause than others. Our findings highlight the clear benefits for women of early smoking cessation to lower their excess risk of earlier menopause

Association of reproductive factors with dementia: a systematic review and dose-response meta-analyses of observational studies

Background: Associations between endogenous estrogen exposure indicators and risk of subtypes of dementia have been unclear. Methods: Databases (PubMed, EMBASE and Web of Science) were searched electronically on 1st July and updated regularly until 12nd November 2021. Observational studies of English language were selected if reported an effect estimate [e.g., odds ratio (OR), rate ratio (RR) or hazard ratio (HR)] and 95% CI for the association between any exposure (age of menarche, age at menopause, reproductive period, estradiol level) and any endpoint variable [all-cause dementia, Alzheimer's disease (AD), vascular dementia (VD), cognitive impairment (CI)]. Random-effects models and dose-response meta-analyses were used to calculate estimates and to show the linear/nonlinear relationship. PROSPERO CRD42021274827. Findings: We included 22 studies (475 9764 women) in this analysis. We found no clear relationship between late menarche (≥14 vs <14 years) and dementia, CI in categorical meta-analysis compared to a J-shape relationship in dose-response meta-analyses. Later menopause (≥45 vs <45 years) was consistently associated with a lower risk of all-cause dementia (pooled RR: 0.87, 95%CI: 0.78–0.97, I2=56.0%), AD (0.67, 0.44–0.99, I2=78.3%), VD (0.87, 0.80–0.94) and CI (0.82, 0.71–0.94, I2=19.3%) in categorical meta-analysis, showing similar results in dose-response meta-analyses. An inverse relationship between longer reproductive duration (≥35 vs <35 years) and dementia was observed in dose-response meta-analysis. In addition, estradiol levels after menopause were inversely correlated with the risk of AD and CI. Interpretation: In this study, later menopause and longer reproductive period were associated with a lower risk of dementia, while the relationship for menarchal age was J-shaped. There was an inverse relationship between higher postmenopausal estrogen levels and risk of AD and CI. Longitudinal study are needed to further explore the association between life-time estrogen exposure and risk of subtypes of dementia. Funding: Start-up Foundation for Scientific Research in Shandong University

Association between hearing aid use and all-cause and cause-specific dementia: an analysis of the UK Biobank cohort.

BACKGROUND: Dementia and hearing loss are both highly prevalent conditions among older adults. We aimed to examine the association between hearing aid use and risk of all-cause and cause-specific dementia among middle-aged and older-aged adults, and to explore the roles of mediators and moderators in their association. METHODS: We used data from the UK Biobank, a population-based cohort study, which recruited adults aged 40-69 years between 2006 and 2010 across 22 centres in England, Scotland, and Wales. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% CIs between self-reported hearing aid use status (hearing loss with or without hearing aids) at baseline and risk of dementia (all-cause dementia, Alzheimer's disease, vascular dementia, and non-Alzheimer's disease non-vascular dementia). Dementia diagnoses were ascertained using hospital records and death-register data. We also analysed the roles of mediators (self-reported social isolation, loneliness, and mood) and moderators (self-reported education and income, smoking, morbidity, and measured APOE allele status). FINDINGS: After the exclusion of people who did not answer the question on hearing difficulties (n=25 081 [5·0%]) and those with dementia at baseline visit (n=283 [0·1%]), we included 437 704 people in the analyses. Compared with participants without hearing loss, people with hearing loss without hearing aids had an increased risk of all-cause dementia (HR 1·42 [95% CI 1·29-1·56]); we found no increased risk in people with hearing loss with hearing aids (1·04 [0·98-1·10]). The positive association of hearing aid use was observed in all-cause dementia and cause-specific dementia subtypes (Alzheimer's disease, vascular dementia, and non-Alzheimer's disease non-vascular dementia). The attributable risk proportion of dementia for hearing loss was estimated to be 29·6%. Of the total association between hearing aid use and all-cause dementia, 1·5% was mediated by reducing social isolation, 2·3% by reducing loneliness, and 7·1% by reducing depressed mood. INTERPRETATION: In people with hearing loss, hearing aid use is associated with a risk of dementia of a similar level to that of people without hearing loss. With the postulation that up to 8% of dementia cases could be prevented with proper hearing loss management, our findings highlight the urgent need to take measures to address hearing loss to improve cognitive decline. FUNDING: National Natural Science Foundation of China and Shandong Province, Taishan Scholars Project, China Medical Board, and China Postdoctoral Science Foundation

Body mass index and age at natural menopause: an international pooled analysis of 11 prospective studies

Current evidence on the association between body mass index (BMI) and age at menopause remains unclear. We investigated the relationship between BMI and age at menopause using data from 11 prospective studies. A total of 24,196 women who experienced menopause after recruitment was included. Baseline BMI was categorised according to the WHO criteria. Age at menopause, confirmed by natural cessation of menses for ≥ 12 months, was categorised as < 45 years (early menopause), 45–49, 50–51 (reference category), 52–53, 54–55, and ≥ 56 years (late age at menopause). We used multinomial logistic regression models to estimate multivariable relative risk ratios (RRRs) and 95% confidence intervals (CI) for the associations between BMI and age at menopause. The mean (standard deviation) age at menopause was 51.4 (3.3) years, with 2.5% of the women having early and 8.1% late menopause. Compared with those with normal BMI (18.5–24.9 kg/m2), underweight women were at a higher risk of early menopause (RRR 2.15, 95% CI 1.50–3.06), while overweight (1.52, 1.31–1.77) and obese women (1.54, 1.18–2.01) were at increased risk of late menopause. Overweight and obesity were also significantly associated with around 20% increased risk of menopause at ages 52–53 and 54–55 years. We observed no association between underweight and late menopause. The risk of early menopause was higher among obese women albeit not significant (1.23, 0.89–1.71). Underweight women had over twice the risk of experiencing early menopause, while overweight and obese women had over 50% higher risk of experiencing late menopause

Establishment and evaluation of different fever related syndromes for screening malaria patients

Aim: Analyze the clinical symptoms of feverish population and select significant symptoms to establish fever related syndromes to screen malaria patients. Method: A“Registration form for patients with fever” was designed to gather information about symptoms of feverish population and standard blood smear was made for each patient to do the microscope test. SPSS 17.0 was used to analyze the distribution of clinical symptoms between malaria patients and non-malaria patients. Then the significant symptoms were selected to establish different syndromes by manual combined method. Sensitivity, positive predictive value (PPV), likelihood ratio, Youden index and Kappa were used for selecting the optimal syndrome. Result: 1508 forms were got and 241 of them were malaria patients. 12 symptoms had different distribution between malaria population and non-malaria population. 52 fever related syndromes were established by using the 12 symptoms. Finally, No.52 syndrome(body temperature above 39⁰C, periodic onset of fever and no diarrhea) were selected as the optimal syndrome, its sensitivity and positive predictive value were 74.3% and 84.4%. Conclusion: The optimal malaria related syndromes can be used as a screen tool to screen malaria patients, especially in the villages where equipment and professional staff were lack

Disease-specific excess mortality during the COVID-19 pandemic: An analysis of weekly US death data for 2020

Objectives: To examine the disease-specific excess deaths during the COVID-19 pandemic in the United States.Methods: We used weekly death data from the National Center for Health Statistics to analyze the trajectories of excess deaths from specific diseases in the United States during the COVID-19 pandemic, at the national level and in 4 states, from the first to 52nd week of 2020. We used the average weekly number of deaths in the previous 6 years (2014-2019) as baseline.Results: Compared with the same week at baseline, the trajectory of number of excess deaths from cardiovascular disease (CVD) was highly parallel to the trajectory of the number of excess deaths related to COVID-19. The number of excess deaths from diabetes mellitus, influenza and respiratory diseases, and malignant neoplasms remained relatively stable over time.Conclusions: The parallel trajectory of excess mortality from CVD and COVID-19 over time reflects the fact that essential health services for noncommunicable diseases were reduced or disrupted during the COVID-19 pandemic, and the severer the pandemic, the heavier the impact

Chemical-and mechanical-induced lubrication mechanisms during hot rolling of titanium alloys using a mixed graphene-incorporating lubricant

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Hot rolling of titanium alloy currently is carried out without lubrication because of the surface defects. In order to explore an effective lubrication scheme to reduce friction and wear during hot rolling of titanium alloy, a mixed graphene-incorporating lubricant has been proposed to study its lubrication performance and mechanism. The tribological experiments were carried out by ball-disk friction and wear tester under hot-rolling parameters. Scanning electron microscopy (SEM), X-ray energy spectrum analyzer (EDS), X-ray powder diffractometer (XRD) and Raman analysis were used to analyse the surface and cross-section of the wear marks on the samples after the tribological experiments. The results show that the friction coefficient decreases up to about 35% compared with tests under dry and lubricated conditions. The surface quality of the wear marks is improved significantly after applying the proposed lubricant. The graphene which is embedded in the phosphate film can be effectively applied as a lubricating material to strengthen the lubricating film with less combustion loss at high temperatures. A chemical-and mechanical-induced lubrication mechanism for the hot rolling of titanium sheets has been proposed due to the synergistic lubrication effect of the graphene, ZrO2 nano particles and phosphate. It is of great significance and potential value to apply this proposed lubricant as an effective way to reduce the wear, friction and oxidation during the hot-rolling process of titanium alloy

Long-Term Food Variety and Dietary Patterns Are Associated with Frailty among Chinese Older Adults: A Cohort Study Based on CLHLS from 2014 to 2018

(1) Objective: To examine the association between posterior-derived dietary patterns, food variety, and frailty measured by frailty index (FI) in Chinese elderly. (2) Method: A cohort study based on the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 2014 to 2018 was conducted among older adults. The food variety was defined by the food variety score (FVS), which was calculated using the frequency of food categories consumption. Dietary patterns were obtained using factor analysis. A FI composed of 38 health deficits was used to measure subjects&rsquo; frailty status. Logistic regression analyses were performed to explore the correlation between dietary factors and the incidence of frailty. (3) Results: Compared with low FVS, a high dietary diversity score at baseline was not associated with a reduced incidence of frailty after four years. Regarding long-term food variety, compared with the low variety maintained group, people with high variety maintained were associated with a lower risk of frailty (0.59, 95%CI 0.39&ndash;0.90). Adherence to the &ldquo;egg-bean-pickle-sugar pattern&rdquo; and &ldquo;fruit-vegetable-meat-fish pattern&rdquo; was associated with a lower risk of frailty. (4) Conclusion: Maintaining high food variety and adherence to two patterns, i.e., the egg-bean-pickle-sugar pattern and fruit-vegetable-meat-fish pattern, could reduce the incidence of frailty among Chinese older adults