Incident Case-control Study Research Articles

Unveiling cancer risk in ANCA-associated vasculitis: result from the Turkish Vasculitis Study Group (TRVaS)

To investigate cancer incidence in patients with ANCA-associated vasculitis (AAV), compare it with the age/sex-specific cancer risk of the Turkish population, and explore independent risk factors associated with cancer. This multicenter, incidence case–control study was conducted using the TRVaS registry. AAV patients without cancer history before AAV diagnosis were included. Demographic and AAV-related data of patients with and without an incident cancer were compared. Standardized cancer incidence rates were calculated using age-/sex-specific 2017 Turkish National Cancer Registry data for cancers (excluding non-melanoma skin cancers). Cox regression was performed to find factors related to incident cancers in AAV patients. Of 461 AAV patients (236 [51.2%] male), 19 had incident cancers after 2022.8 patient-years follow-up. Median (IQR) disease duration was 3.4 (5.5) years, and 58 (12.6%) patients died [7 with cancer and one without cancer (log-rank, p = 0.04)]. Cancer-diagnosed patients were older, mostly male, and more likely to have anti-PR3-ANCA positivity. The cumulative cyclophosphamide dose was similar in patients with and without cancer. Overall cancer risk in AAV was 2.1 (SIR) ((1.3–3.2), p = 0.004); lung and head-neck [primary target sites for AAV] cancers were the most common. In Cox regression, male sex and ≥ 60 years of age at AAV diagnosis were associated with increased cancer risk, while receiving rituximab was associated with decreased cancer risk. Cancer risk was 2.1 times higher in AAV patients than the age-/sex-specific cancer risk of the Turkish population population, despite a high rate of rituximab use and lower dose of cyclophosphamide doses. Vigilance in cancer screening for AAV patients covering lung, genitourinary, and head–neck regions, particularly in males and the elderly, is vital.

Association between amino acids and recent osteoporotic fracture: a matched incident case-control study.

Osteoporotic fracture is a major public health issue globally. Human research on the association between amino acids (AAs) and fracture is still lacking. To examine the association between AAs and recent osteoporotic fractures. This age and sex matched incident case-control study identified 44 recent x-ray confirmed fracture cases in the Second Hospital of Jilin University and 88 community-based healthy controls aged 50+ years. Plasma AAs were measured by high performance liquid chromatography coupled with mass spectrometry. After adjusting for covariates (i.e., body mass index, milk intake >1 time/week, falls and physical activity), we conducted conditional logistical regression models to test the association between AAs and fracture. Among cases there were 23 (52.3%) hip fractures and 21 (47.7%) non-hip fractures. Total, essential, and non-essential AAs were significantly lower in cases than in controls. In the multivariable conditional logistic regression models, after adjusting for covariates, each standard deviation increase in the total (odds ratio [OR]: 0.304; 95% confidence interval [CI]: 0.117-0.794), essential (OR: 0.408; 95% CI: 0.181-0.923) and non-essential AAs (OR: 0.290; 95%CI: 0.107-0.782) was negatively associated with recent fracture. These inverse associations were mainly found for hip fracture, rather than non-hip fractures. Among these AAs, lysine, alanine, arginine, glutamine, histidine and piperamide showed the significantly negative associations with fracture. There was a negative relationship between AAs and recent osteoporotic fracture; such relationship appeared to be more obvious for hip fracture.

Impact of Alcohol Consumption on Multiple Sclerosis Using Model-based Standardization and Misclassification Adjustment Via Probabilistic Bias Analysis.

The etiology of multiple sclerosis (MS) is still not well-demonstrated, and assessment of some risk factors like alcohol consumption has problems like confounding and measurement bias. To determine the causal effect of alcohol consumption on MS after adjusting for alcohol consumption misclassification bias and confounders. In a population-based incident case-control study, 547 patients with MS and 1057 healthy people were recruited. A minimally sufficient adjustment set of confounders was derived using the causal directed acyclic graph. The probabilistic bias analysis method (PBAM) using beta, logit-logistic, and triangular probability distributions for sensitivity/specificity to adjust for misclassification bias in self-reporting alcohol consumption and model-based standardization (MBS) to estimate the causal effect of alcohol consumption were used. Population attributable fraction (PAF) estimates with 95% Monte Carlo sensitivity analysis (MCSA) intervals were calculated using PBAM and MBS analysis. Bootstrap was used to deal with random errors. The adjusted risk ratio (95% MCSA interval) from the probabilistic bias analysis and MBS between alcohol consumption and MS using the three distribution was in the range of 1.93 (1.07 to 4.07) to 2.02 (1.15 to 4.69). The risk difference (RD) in all three scenarios was 0.0001 (0.0000 to 0.0005) and PAF was in the range of 0.15 (0.010 to 0.50) to 0.17 (0.001 to 0.47). After adjusting for measurement bias, confounding, and random error alcohol consumption had a positive causal effect on the incidence of MS.

Anogenital distance, a biomarker of fetal androgen exposure and the risk of prostate cancer: A case-control study.

Evaluate the association between AGD and the risk of PCa. Incident case-control study, conducted on 153 patients. All patients underwent prostate biopsy for abnormal digital rectal exam and/or prostate antigen elevation. Two variants of AGD [anus to scrotum base (AGDas) and anus to dorsal insertion of penis (AGDap) were measured. Student's t-test was used to analyze continuous variables and chi-square for discrete variables. Differences in AGD (raw and adjusted) measures between cases and controls were assessed using the ANCOVA test. There is significant association between the diagnose of PCa and both AGD, patients diagnosed with PCa had both AGD measures shortened, in the crude and the full adjusted models. This research suggests that the same gestational environmental exposures, could represent a weak androgen signaling and may also have an increased risk of prostate cancer.

Association between socioeconomic status and Parkinson’s disease: findings from a large incident case–control study

IntroductionThe association between socioeconomic status (SES) and Parkinson’s disease (PD) has been investigated in few studies. To our knowledge, SES measurement based on wealth index and perceived SES in PD...

What role for asbestos in idiopathic pulmonary fibrosis? Findings from the IPF job exposures case–control study

BackgroundAsbestos has been hypothesised as the cause of the recent global increase in the incidence of ‘idiopathic’ pulmonary fibrosis (IPF). Establishing this has important diagnostic and therapeutic implications. The association...

Brain computed tomography perfusion analysis in HIV-seropositive adults with and without neurocognitive impairment in Nigeria: outcomes and challenges of a pilot study.

the significance of cerebrovascular disease in HIV-associated neurocognitive disorder (HAND) in a homogeneous black population has not yet been determined. This incident case-control study used CT perfusion imaging to quantify and compare regional cerebral blood flow parameters in neuro-cognitively impaired and unimpaired HIV+ participants of the Ibadan Cohort on Neuro AIDS (ICON) in Nigeria. this was an incident case-control study consisting of twenty-seven HIV+ adults, classified based on Frascati criteria into neurocognitive impaired (n=18) and unimpaired (n=9) groups, who had brain computed tomographic perfusion (CTP) with a 64-slice Toshiba T scanner. The standard deviation (SD) of regional mean transit time (MTT), cerebral blood flow (CBF), and cerebral blood volume (CBV) values were calculated for bilateral basal ganglia (BG), frontal, parietal, temporal, and occipital regions from CT perfusion maps. The regional mean values and variability (SD) in the CTP measures were compared in the groups using an independent student t-test. differentially higher variability in the bilateral CBF measures in the parietal (right; OR = 1.14, x̄ =5.61, p=0.041, CI=0.27-11.35/left; OR = 1.16, x̄=7.01, p=0.03, CI=5.6-13.47) and time to peak (TTP) measures in the basal ganglia (right; OR = 3.78, x̄=0.88, p=0.032, CI=0.081-1.67/left; OR = 2.44, x̄=1.48, p=0.020, CI=0.26-2.71) and occipital (right; OR = 2.18, x̄=1.32, p=0.018, CI=0.25-2.38/left; OR = 1.93, x̄=1.08, p=0.034, CI=0.086-2.06) regions were observed in the cognitively impaired group compared to the unimpaired group. the study evidence suggests that alterations in cerebral perfusion implicated in HIV-associated neurocognitive disorder may be possibly demonstrated using CTP, a readily available resource in most African countries saddled with the highest burden of HIV.

Additive interaction between dietary inflammatory index and some key risk factors of multiple sclerosis: a population-based incident case–control study

ABSTRACT Background Recently, dietary inflammatory index (DII) has been introduced as a significant risk factor for MS. We examined the interaction between dietary inflammatory index and some formerly demonstrated key risk factors of multiple sclerosis (MS). Material and Methods We conducted a population-based incident case–control study of 547 MS cases and 1057 controls. Multiplicative and additive interaction were assessed using interaction term in the logistic regression model and synergy index (SI), respectively. Results Additive interaction was detected between DII and drug abuse (SI = 2.58; 95% CI: 1.14–5.82), gender (SI = 2.00; 95% CI: 1.39–2.87) and history of depression (SI = 1.68; 95% CI: 1.04–2.72) on the risk scale. The risk of MS in drug abusers with DII ≥ 0 was 10.4-times higher than that in non-drug abusers with DII < 0 (OR = 10.4, 95% CI: 5.12–21.02, P < 0.001). We also found that women with DII ≥ 0 had a 9.2 times larger risk compared with the men with DII < 0(OR = 9.2, 95% CI: 6.3–13.5, P < 0.001). Similarly, the risk of MS was remarkably higher in those with a history of depression and DII >0 (OR = 7.6, 95% CI: 5.1–11.5, P < 0.001). There was no evidence of multiplicative interaction between DII and the other risk factors of MS on the risk scale. Conclusions We identified additive interaction between DII and drug abuse, gender and history of depression on MS. Further studies are needed to understand the underlying mechanisms of these detected interactions.

Inorganic arsenic in drinking water and breast cancer risk: a case-control study in Northern Chile

BACKGROUND AND AIM: Exposure to arsenic in drinking water is a well-established cause of lung, bladder and skin cancer, however the relation between arsenic and breast cancer is less clear. Between 2014-2018, we conducted a breast cancer incident case-control study in Northern Chile, where from 1950-1970 the population was exposed to high levels of arsenic in drinking water (up to 900 &amp;#x3bc;g/l). METHODS: We analyzed 703 breast cancer cases and 491 population-based female controls with data collected on lifetime exposure to As and potential confounders. Using logistic regression, we tested whether exposure to higher levels of arsenic in drinking water related to differential risk of breast cancer. Initial causal models adjusted for age and education. Additional models included other known risk factors for breast cancer and several sensitivity analyses evaluated different exposure windows. RESULTS: Both cases and controls were around 58 years of age and about half had finished high school or had additional studies. Cases, compared to controls, were exposed to lower median concentrations of arsenic (&amp;#x3bc;g/L): 60 [interquartile range (IQR), 11-636] versus 70 (40-299). Adjusted odds ratios for category of highest single-year arsenic concentrations in water (&amp;#x3c;49, 50-199, 200-799, and &amp;#x2265; 800 &amp;#x3bc;g/L) were 1.00, 0.70 [95% confidence interval (CI), 0.52-0.94], 0.71 (0.51-1.01), and 1.02 (0.72-1.44), respectively. Results were similar after various adjustments, using different metrics of arsenic exposure, and windows of exposure. CONCLUSIONS: Compared with women with the lowest levels of exposure to arsenic in drinking water, those with higher (up to 799 &amp;#x3bc;g/L) arsenic exposure, had lower odds of breast cancer, in accordance with evidence implying a potentially therapeutic effect of arsenic exposure. Differential arsenic sensitivity of breast cancer cell types may explain differences in the direction of the effect and lack of precision for some exposure groups. KEYWORDS: arsenic, breast cancer, drinking water

INTERBLEED: Design of an International Study of Risk Factors for Gastrointestinal Bleeding and Cardiovascular Events After Gastrointestinal Bleeding

BackgroundBleeding is the most common adverse event in those with cardiovascular (CV) disease receiving antithrombotic therapy, and it most commonly occurs in the gastrointestinal (GI) tract. Clinicians often dismiss bleeding as an adverse event that is reversible with effective antithrombotic therapy, but bleeding is associated with substantial morbidity and mortality, most likely mediated through an increased risk of CV events. Reducing the burden of bleeding requires knowledge of the potentially modifiable risk factors for bleeding and the potentially modifiable risk factors for adverse outcomes after bleeding. MethodsINTERBLEED is an international, multicentre, 2-component, observational study, with an incident case-control study examining the risk factors for GI bleeding, and a prospective cohort study of risk factors for CV events after GI bleeding. Cases either have CV disease and present to the hospital with GI bleeding or develop GI bleeding during hospitalization. Controls have CV disease, but no history of GI bleeding. We use a questionnaire to obtain detailed information on known and potential risk factors for GI bleeding and for CV events and outcomes after bleeding. We obtain CV and anthropometric measurements, perform functional and cognitive assessments, and follow participants at 3 months and 12 months. ResultsAs of April 1, 2022, the study is ongoing in 10 countries at 31 centres and has recruited 2407 cases and 1478 controls. ConclusionsKnowledge of risk factors for bleeding, and risk factors for CV events and functional decline after bleeding, will help develop strategies to prevent bleeding and subsequent complications.

Clostridioides difficile infection in a rural New Zealand secondary care centre: an incidence case-control study.

Clostridioides difficile infection (CDI) is a form of antibiotic-associated infectious diarrhoea resulting in significant morbidity and mortality. Community-acquired disease in low-risk individuals is increasingly recognised. There are limited New Zealand data published. To determine the incidence and location of onset of CDI cases in the Manawatu region, and further describe the demographics, risk factors and prevalent C. difficile ribotypes of the population. We performed an incidence case-control study of CDI in the Manawatu region between September 2018 and September 2019. Cases were matched to controls with a negative test for C. difficile. Demographic and comorbidity data, location of onset, drug exposure, disease recurrence and 30-day mortality were collected. Ribotype analysis was performed on C. difficile isolates. Thirty-two specimens tested toxin positive over 12 months, yielding an incidence of 18.3 cases per 100 000 person-years. Twenty-five percent of cases had community onset disease. Cases were more likely to have had amoxicillin/clavulanate or ceftriaxone prescribed. Elevated blood white cell count and lower HbA1c were significantly associated with CDI. The dominant ribotype was 014/020. Two cases were RT 023. Our data are similar to previous national data. RT 023 has not been previously reported in New Zealand and has been associated with severe colitis. We demonstrated a significant proportion of community-acquired cases and the true incidence might be higher. Vigilance for community onset disease is required. These data may allow observation of temporal changes in incidence and infection patterns of CDI in New Zealand.

Association of Lipids, Lipoproteins, and Apolipoproteins with Stroke Subtypes in an International Case Control Study (INTERSTROKE).

Background and Purpose The association of dyslipidemia with stroke has been inconsistent, which may be due to differing associations within etiological stroke subtypes. We sought to determine the association of lipoproteins and apolipoproteins within stroke subtypes. Methods Standardized incident case-control STROKE study in 32 countries. Cases were patients with acute hospitalized first stroke, and matched by age, sex and site to controls. Concentrations of total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein A1 (apoA1), and apoB were measured. Non-HDL-C was calculated. We estimated multivariable odds ratio (OR) and population attributable risk percentage (PAR%). Outcome measures were all stroke, ischemic stroke (and subtypes), and intracerebral hemorrhage (ICH). Results Our analysis included 11,898 matched case-control pairs; 77.3% with ischemic stroke and 22.7% with ICH. Increasing apoB (OR, 1.10; 95% confidence interval [CI], 1.06 to 1.14 per standard deviation [SD]) and LDL-C (OR, 1.06; 95% CI, 1.02 to 1.10 per SD) were associated with an increase in risk of ischemic stroke, but a reduced risk of ICH. Increased apoB was significantly associated with large vessel stroke (PAR 13.4%; 95% CI, 5.6 to 28.4) and stroke of undetermined cause. Higher HDL-C (OR, 0.75; 95% CI, 0.72 to 0.78 per SD) and apoA1 (OR, 0.63; 95% CI, 0.61 to 0.66 per SD) were associated with ischemic stroke (and subtypes). While increasing HDL-C was associated with an increased risk of ICH (OR, 1.20; 95% CI, 1.14 to 1.27 per SD), apoA1 was associated with a reduced risk (OR, 0.80; 95% CI, 0.75 to 0.85 per SD). ApoB/A1 (OR, 1.38; 95% CI, 1.32 to 1.44 per SD) had a stronger magnitude of association than the ratio of LDL-C/HDL-C (OR, 1.26; 95% CI, 1.21 to 1.31 per SD) with ischemic stroke (P<0.0001). Conclusions The pattern and magnitude of association of lipoproteins and apolipoproteins with stroke varies by etiological stroke subtype. While the directions of association for LDL, HDL, and apoB were opposing for ischemic stroke and ICH, apoA1 was associated with a reduction in both ischemic stroke and ICH. The ratio of apoB/A1 was the best lipid predictor of ischemic stroke risk.

Severity of omicron variant of concern and effectiveness of vaccine boosters against symptomatic disease in Scotland (EAVE II): a national cohort study with nested test-negative design

BackgroundSince its emergence in November, 2021, in southern Africa, the SARS-CoV-2 omicron variant of concern (VOC) has rapidly spread across the world. We aimed to investigate the severity of omicron and the extent to which booster vaccines are effective in preventing symptomatic infection.MethodsIn this study, using the Scotland-wide Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE II) platform, we did a cohort analysis with a nested test-negative design incident case-control study covering the period Nov 1–Dec 19, 2021, to provide initial estimates of omicron severity and the effectiveness of vaccine boosters against symptomatic disease relative to 25 weeks or more after the second vaccine dose. Primary care data derived from 940 general practices across Scotland were linked to laboratory data and hospital admission data. We compared outcomes between infection with the delta VOC (defined as S-gene positive) and the omicron VOC (defined as S-gene negative). We assessed effectiveness against symptomatic SARS-CoV-2 infection, with infection confirmed through a positive RT-PCR.FindingsBy Dec 19, 2021, there were 23 840 S-gene-negative cases in Scotland, which were predominantly among those aged 20–39 years (11 732 [49·2%]). The proportion of S-gene-negative cases that were possible reinfections was more than ten times that of S-gene-positive cases (7·6% vs 0·7%; p<0·0001). There were 15 hospital admissions in S-gene-negative individuals, giving an adjusted observed-to-expected admissions ratio of 0·32 (95% CI 0·19–0·52). The booster vaccine dose was associated with a 57% (54–60) reduction in the risk of symptomatic S-gene-negative infection relative to individuals who tested positive 25 weeks or more after the second vaccine dose.InterpretationThese early national data suggest that omicron is associated with a two-thirds reduction in the risk of COVID-19 hospitalisation compared with delta. Although offering the greatest protection against delta, the booster dose of vaccination offers substantial additional protection against the risk of symptomatic COVID-19 for omicron compared with 25 weeks or more after the second vaccine dose.FundingHealth Data Research UK, National Core Studies, Public Health Scotland, Scottish Government, UK Research and Innovation, and University of Edinburgh.

Associated between Dietary Antioxidant Index (DAI) and Odds of Breast Cancer and Correlation between DAI with Pathobiological Markers: Hospital-Based Incidence Case-Control Study

Background: The relationship between dietary antioxidants and breast cancer (BrCa) has been investigated in various studies. As a limitation, they generally investigate the relationship between one specific antioxidant and the risk/odds of BrCa, and synergistic or inhibitory effects are less considered. Dietary antioxidant index (DAI) is a reliable nutritional tool that evaluates total nutritional antioxidant capacity and is validated with serum total antioxidant capacity (TAC) and Malondialdehyde (MDA). Our study aimed to investigate the association between the DAI and the odds of BrCa and the correlation between the DAI and pathobiological markers. We hypnotized a correlation between DAI and pathobiological markers, and there is an association between DAI and the odds of BrCa. Methods: Our study included 145 incidence cases of BrCa and 148 hospital-based controls. Controls were randomly selected from patients attending the same center and were frequency-matched on age (±10 years). DAI was calculated based on a valid semi-quantitative 168-item food frequency questionnaire data. DAI standardizes intake of major dietary antioxidants, including vitamins A, E, C, selenium, zinc, and magnesium, and presents them as summarized scores. Results: Modeling with multivariable regressions adjusting for major confounders including age, education, body mass index, occupation, alcohol, smoking, pregnancy, history of cancer, menarche age, metabolic equivalent of task, hormone replacement therapy, and total energy intake, there was a significant association between odds of BrCa and DAI (odds ratio = 0.18; 95% confidence interval:0.09-0.37; p-value= <0.01). After multiple controls, there was a significant and weak reverse correlation between DAI and the number of lymph node(s) (correlation coefficient= −.140; p-value = 0.05). Conclusion: Our study supports the hypothesis that dietary antioxidants intake is associated with a reduced odds of BrCa. Evidently, DAI can reveal these relationships better than a single study of antioxidants. However, further studies are needed to confirm or refute these results.

Antioxidant potential of diet – Association between dietary antioxidant index and odds of coronary heart disease: A case-control study

BACKGROUND: Oxidative stress and chronic inflammation are among the leading causes of coronary heart disease (CHD). Studies investigated the relationship between dietary antioxidants and the risk/odds of CHD, and contradictory results have been reported. Dietary antioxidant index (DAI) is a novel and reliable nutritional tool that examines the diet’s overall antioxidant capacity. Its validity was examined using serum total antioxidant capacity and malondialdehyde. OBJECTIVE: This study aimed to investigate the relationship between DAI score and odds of CHD. METHODS: In this incidence case-control study, 320 individuals with a definitive diagnosis of CHD and 320 participants without CHD or related risk factors attending the same hospitals/polyclinics were selected as the case and control groups. We estimated the DAI by summing up six standardized intakes of major dietary antioxidants, including manganese, vitamin E, A, C, selenium, and zinc. RESULTS: Modeling DAI categorized according to the median (–0.38), in multi-adjusted model showed a significant protective association with the odd of CHD (OR = 0.72; 95%CI:0.51–0.99, p-value = 0.05). Also, modeling DAI as a continuous variable in multi-adjusted models (OR = 0.94;95%CI:0.90–0.95; p-value = 0.01) showed significant results. CONCLUSION: Using the DAI to investigate the relationship between dietary antioxidants and CHD can show more realistic results than a single study of antioxidants.

Dietary habits, nutritional status and risk of a first demyelinating event: an incident case-control study in a southern European cohort.

The relationship between dietary habits and multiple sclerosis (MS) risk is still controversial. Most studies have involved populations from Scandinavia, North America, and Australia. Data on populations from southern Europe (an area of high MS prevalence) are scarce. To examine the association between dietary habits/nutritional status and risk of a first demyelinating event, in a southern European incident cohort. In this incident case-control study, a detailed nutritional assessment was performed by a registered dietitian in patients with a first demyelinating event, and in age-/sex-matched controls. Body composition analysis, anthropometric evaluation, and blood tests for nutritional status were also performed. Eighty-three patients with a first demyelinating event were prospectively recruited over a 1-year period. Low intake of fibers (OR 0.846, p = 0.014), vitamin D (OR 0.730, p < 0.0001), and alpha-linolenic acid (OR 0.283, p = 0.014), high BMI (OR 1.132, p = 0.028), and ever smoker status (OR 4.472, p = 0.003) were all independently associated with risk of a first demyelinating event. Higher intake of rapid absorption carbohydrates, lower intake of vegetal proteins, and higher intake of animal proteins were observed in patients with a first demyelinating event. Significant differences between patients and controls are observed in the dietary habits at the time of a first demyelinating event, suggesting low intake of fibers, vitamin D and alpha-linolenic acid as the main dietary risk factors. Furthermore, high cardiovascular risk dietary habits are frequent at the time of MS onset, suggesting the usefulness of nutritional intervention as part of the activities of MS centers.

Dietary risk factors of primary progressive multiple sclerosis: A population-based case-control study

ObjectivesThere are growing evidences on the role of nutritional factors in multiple sclerosis (MS) occurrence. But dietary data are limited in primary progressive type of MS (PPMS). We assessed the role of dietary factors during adolescence in PPMS risk. MethodsAn incident case-control study on 143 PPMS cases with definite diagnosis and 400 controls were conducted in Sina hospital, Tehran, Iran. Demographic data were collected. Data on nutritional habits during adolescence were obtained using questionnaire designed for multinational case–control studies of environmental risk factors for multiple sclerosis (EnvIMS-Q). Logistic regression models were run to evaluate the role of diet in PPMS risk. ResultsA significant association was founded between higher intake of dairy, seafood, red meat, poultry, vegetable, fruit and nut and lower risk of PPMS (P< 00.5). This association was dose dependent for all mentioned food groups except fruit. In the fully adjusted model, more intake of dairy (OR: 0.27; 95%CI: 0.14-0.53), seafood (OR: 0.21; 95%CI: 0.10-0.44), red meat (OR:0.44; 95%CI: 0.22-0.90), vegetable (OR: 0.19; 95%CI: 0.09-0.39), fruit (OR: 0.47; 95%CI: 0.22-0.99) and nut (OR: 0.29; 95%CI: 0.15-0.56) in the third tertiles resulted in significant reduction in PPMS risk. In case of poultry consumption, the association was meaningful just in the third tertile of crude model (OR: 0.54; 95%CI: 0.30-0.95). Nutrient supplementation with calcium, iron, folic acid, vitamin B12 and C were also related with more than 84% lower risk of PPMS. ConclusionOur data proposed that adequate intake of food groups and nutrient supplementation during adolescence may be effective in reducing adult-onset PPMS risk.

Occupation and subcategories of asthma: a population-based incident case–control study

BackgroundWe hypothesised that occupational exposures differently affect subtypes of adult-onset asthma.ObjectiveWe investigated potential relations between occupation and three subtypes of adult asthma, namely atopic asthma, non-atopic asthma and asthma–COPD overlap...

Non-opioid recreational drug use and a prolonged HIV outbreak among men who have sex with men in Taiwan: An incident case-control study, 2006–2015

Limited data are available on the role of illicit non-injecting drug use in a prolonged HIV outbreak that predominantly affected men who have sex with men (MSM) in Taiwan since 2006. We aimed to assess associations between specific types of drug use and incident HIV infections in this outbreak. We conducted a retrospective case-control study among MSM clients at voluntary counselling and testing (VCT) service at National Taiwan University Hospital (Taipei, Taiwan). We used BED IgG-capture enzyme immunoassay to identify incident HIV infection (cases), individually matched to HIV-negative MSM clients (controls) by HIV testing date. We used a structured questionnaire to obtain the information on illicit drug use and sexual risk behaviors. From a total of 15,305 MSM client visits during 2006-2015, 387 cases were matched to 1012 controls. Use of inhaled nitrites (adjusted odds ratio [aOR] 2.1), MDMA (aOR 2.9), amphetamines (aOR 1.6), and ketamine (aOR 1.5) were independently associated with incident HIV infection. Polydrug (≥2 drugs) use was associated with the highest risk (aOR 4.3; 95% CI 2.6-7.2). While the proportion of MSM VCT clients who reported use of any recreational drug remained stable during 2006-2015 (average: 9.7%, P: 0.38), there was a shift in specific types of drug use, from MDMA/ketamine to inhaled nitrites/amphetamine, after 2011 (all Ps<0.05). Non-opioid recreational drugs use is associated with incident HIV infection in this prolonged HIV outbreak. There is an urgent need to formulate an effective public health response to mitigate the risk.

Estimating the Marginal Causal Effect and Potential Impact of Waterpipe Smoking on Risk of Multiple Sclerosis Using the Targeted Maximum Likelihood Estimation Method: A Large, Population-Based Incident Case-Control Study.

There are few if any reports regarding the role of lifetime waterpipe smoking in the etiology of multiple sclerosis (MS). In a population-based incident case-control study conducted in Tehran, Iran, we investigated the association between waterpipe smoking and MS, adjusted for confounders. Cases (n=547) were patients aged 15-50 years identified from the Iranian Multiple Sclerosis Society between 2013 and 2015. Population-based controls (n=1,057) were persons aged 15-50 years recruited through random digit telephone dialing. A doubly robust estimation method, the targeted maximum likelihood estimator (TMLE), was used to estimate the marginal risk ratio and odds ratio for the association between waterpipe smoking and MS. The estimated risk ratio and odds ratio were both 1.70 (95% confidence interval: 1.34, 2.17). The population attributable fraction was 21.4% (95% confidence interval: 4.0, 38.8). Subject to the limitations of case-control studies in interpreting associations causally, these results suggest that waterpipe use, or strongly related but undetermined factors, increases the risk of MS. Further epidemiologic studies, including nested case-control studies, are needed to confirm these findings.