Early estimates of SARS-CoV-2 Omicron variant severity based on a matched cohort study, Ontario, Canada

While it is now evident that Omicron is rapidly replacing Delta, due to a combination of increased transmissibility and immune escape, it is less clear how the severity of Omicron compares to Delta. In Ontario, we sought to examine hospitalization and death associated with Omicron, as compared to matched cases infected with Delta. We conducted a matched cohort study, considering time to hospitalization or death as the outcome, and analyzed with a Cox proportional hazards model. Cases were matched on age, gender, and onset date, while vaccine doses received and time since vaccination were included as adjustment variables. We identified 6,314 Omicron cases that met eligibility criteria, of which 6,312 could be matched with at least one Delta case (N=8,875) based on age, gender, and onset date. There were 21 (0.3%) hospitalizations and 0 (0%) deaths among matched Omicron cases, compared to 116 (2.2%) hospitalizations and 7 (0.3%) deaths among matched Delta cases. The adjusted risk of hospitalization or death was 54% lower (HR=0.46, 95%CI: 0.27, 0.77) among Omicron cases compared to Delta cases. While severity may be reduced, the absolute number of hospitalizations and impact on the healthcare system could still be significant due to the increased transmissibility of Omicron.

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Primary versus postoperative stereotactic radiosurgery for acromegaly: a multicenter matched cohort study

Journal of Neurosurgery ◽

10.3171/2019.1.jns183398 ◽

2020 ◽

Vol 132 (5) ◽

pp. 1507-1516 ◽

Cited By ~ 2

Author(s):

Nasser Mohammed ◽

Dale Ding ◽

Yi-Chieh Hung ◽

Zhiyuan Xu ◽

Cheng-Chia Lee ◽

...

Keyword(s):

Cohort Study ◽

Stereotactic Radiosurgery ◽

Biochemical Recurrence ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Tumor Control ◽

Study Cohort ◽

Matched Cohort ◽

Matched Cohort Study

OBJECTIVEThe role of primary stereotactic radiosurgery (SRS) in patients with medically refractory acromegaly who are not operative candidates or who refuse resection is poorly understood. The aim of this multicenter, matched cohort study was to compare the outcomes of primary versus postoperative SRS for acromegaly.METHODSThe authors reviewed an International Radiosurgery Research Foundation database of 398 patients with acromegaly who underwent SRS and categorized them into primary or postoperative cohorts. Patients in the primary SRS cohort were matched, in a 1:2 ratio, to those in the postoperative SRS cohort, and the outcomes of the 2 matched cohorts were compared.RESULTSThe study cohort comprised 78 patients (median follow-up 66.4 months), including 26 and 52 in the matched primary and postoperative SRS cohorts, respectively. In the primary SRS cohort, the actuarial endocrine remission rates at 2 and 5 years were 20% and 42%, respectively. The Cox proportional hazards model showed that a lower pre-SRS insulin-like growth factor–1 level was predictive of initial endocrine remission (p = 0.03), whereas a lower SRS margin dose was predictive of biochemical recurrence after initial remission (p = 0.01). There were no differences in the rates of radiological tumor control (p = 0.34), initial endocrine remission (p = 0.23), biochemical recurrence after initial remission (p = 0.33), recurrence-free survival (p = 0.32), or hypopituitarism (p = 0.67) between the 2 matched cohorts.CONCLUSIONSPrimary SRS has a reasonable benefit-to-risk profile for patients with acromegaly in whom resection is not possible, and it has similar outcomes to endocrinologically comparable patients who undergo postoperative SRS. SRS with medical therapy in the latent period can be used as an alternative to surgery in selected patients who cannot or do not wish to undergo resection.

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Regular Use of VKA Prior to COVID-19 Associated with Lower 7-Day Survival in Hospitalized Frail Elderly COVID-19 Patients: The GERIA-COVID Cohort Study

Nutrients ◽

10.3390/nu13010039 ◽

2020 ◽

Vol 13 (1) ◽

pp. 39

Author(s):

Pierre Ménager ◽

Olivier Brière ◽

Jennifer Gautier ◽

Jérémie Riou ◽

Guillaume Sacco ◽

...

Keyword(s):

Cohort Study ◽

Vitamin K ◽

Frail Elderly ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Clinical Severity ◽

Survival Times ◽

Short Term Mortality

Background. Vitamin K concentrations are inversely associated with the clinical severity of COVID-19. The objective of this cohort study was to determine whether the regular use of vitamin K antagonist (VKA) prior to COVID-19 was associated with short-term mortality in frail older adults hospitalized for COVID-19. Methods. Eighty-two patients consecutively hospitalized for COVID-19 in a geriatric acute care unit were included. The association of the regular use of VKA prior to COVID-19 with survival after 7 days of COVID-19 was examined using a propensity-score-weighted Cox proportional-hazards model accounting for age, sex, severe undernutrition, diabetes mellitus, hypertension, prior myocardial infarction, congestive heart failure, prior stroke and/or transient ischemic attack, CHA2DS2-VASc score, HAS-BLED score, and eGFR. Results. Among 82 patients (mean ± SD age 88.8 ± 4.5 years; 48% women), 73 survived COVID-19 at day 7 while 9 died. There was no between-group difference at baseline, despite a trend for more frequent use of VKA in those who did not survive on day 7 (33.3% versus 8.2%, p = 0.056). While considering “using no VKA” as the reference (hazard ratio (HR) = 1), the HR for 7-day mortality in those regularly using VKA was 5.68 [95% CI: 1.17; 27.53]. Consistently, COVID-19 patients using VKA on a regular basis had shorter survival times than the others (p = 0.031). Conclusions. Regular use of VKA was associated with increased mortality at day 7 in hospitalized frail elderly patients with COVID-19.

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Associations between SARS-CoV-2 variants and risk of COVID-19 hospitalization among confirmed cases in Washington State: a retrospective cohort study

10.1101/2021.09.29.21264272 ◽

2021 ◽

Author(s):

Miguel I. Paredes ◽

Stephanie Lunn ◽

Michael Famulare ◽

Lauren A. Frisbie ◽

Ian Painter ◽

...

Keyword(s):

Cohort Study ◽

Retrospective Cohort Study ◽

Retrospective Cohort ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Sentinel Surveillance ◽

Cox Proportional Hazards Model ◽

Ancestral Lineage ◽

Significant Difference

Background: The COVID–19 pandemic is now dominated by variant lineages; the resulting impact on disease severity remains unclear. Using a retrospective cohort study, we assessed the risk of hospitalization following infection with nine variants of concern or interest (VOC/VOI). Methods: Our study includes individuals with positive SARS–CoV–2 RT PCR in the Washington Disease Reporting System and with available viral genome data, from December 1, 2020 to July 30, 2021. The main analysis was restricted to cases with specimens collected through sentinel surveillance. Using a Cox proportional hazards model with mixed effects, we estimated hazard ratios (HR) for the risk of hospitalization following infection with a VOC/VOI, adjusting for age, sex, and vaccination status. Findings: Of the 27,814 cases, 23,170 (83.3%) were sequenced through sentinel surveillance, of which 726 (3.1%) were hospitalized due to COVID–19. Higher hospitalization risk was found for infections with Gamma (HR 3.17, 95% CI 2.15–4.67), Beta (HR: 2.97, 95% CI 1.65–5.35), Delta (HR: 2.30, 95% CI 1.69–3.15), and Alpha (HR 1.59, 95% CI 1.26–1.99) compared to infections with an ancestral lineage. Following VOC infection, unvaccinated patients show a similar higher hospitalization risk, while vaccinated patients show no significant difference in risk, both when compared to unvaccinated, ancestral lineage cases. Interpretation: Infection with a VOC results in a higher hospitalization risk, with an active vaccination attenuating that risk. Our findings support promoting hospital preparedness, vaccination, and robust genomic surveillance.

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Fish intake and the risk of fatal prostate cancer: findings from a cohort study in Japan

Public Health Nutrition ◽

10.1017/s1368980008003182 ◽

2009 ◽

Vol 12 (5) ◽

pp. 609-613 ◽

Cited By ~ 24

Author(s):

Truong-Minh Pham ◽

Yoshihisa Fujino ◽

Tatsuhiko Kubo ◽

Reiko Ide ◽

Noritaka Tokui ◽

...

Keyword(s):

Prostate Cancer ◽

Cohort Study ◽

Fish Consumption ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Inverse Association ◽

High Intake ◽

Risk Of Death

AbstractObjectiveWe investigated the relationship between the intake of fish and the risk of death from prostate cancer.DesignData were derived from a prospective cohort study in Japan. Fish consumption obtained from a baseline questionnaire was classified into the two categories of ‘low intake’ and ‘high intake’. The Cox proportional hazards model was used to estimate hazard ratios (HR) and 95 % confidence intervals.SubjectsData for 5589 men aged 30–79 years were analysed.ResultsA total of twenty-one prostate cancer deaths were observed during 75 072 person-years of follow-up. Mean age at baseline study of these twenty-one subjects was 67·7 years, ranging from 47 and 79 years old. Results showed a consistent inverse association of this cancer between the high v. low intake groups. The multivariate model adjusted for potential confounding factors and some other food items showed a HR of 0·12 (95 % CI 0·05, 0·32) for the high intake group of fish consumption.ConclusionsThese results support the hypothesis that a high intake of fish may decrease the risk of prostate cancer death. Given the paucity of studies examining the association between prostate cancer and fish consumption, particularly in Asian populations, these findings require confirmation in additional cohort studies.

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Outcomes in Critically Ill Patients Sedated with Intravenous Lormetazepam or Midazolam: A Retrospective Cohort Study

Journal of Clinical Medicine ◽

10.3390/jcm10184091 ◽

2021 ◽

Vol 10 (18) ◽

pp. 4091

Author(s):

Björn Weiss ◽

David Hilfrich ◽

Gerald Vorderwülbecke ◽

Maria Heinrich ◽

Julius J. Grunow ◽

...

Keyword(s):

Cohort Study ◽

Critically Ill ◽

Retrospective Cohort Study ◽

Critically Ill Patients ◽

Retrospective Cohort ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Medical Center ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model

The benzodiazepine, midazolam, is one of the most frequently used sedatives in intensive care medicine, but it has an unfavorable pharmacokinetic profile when continuously applied. As a consequence, patients are frequently prolonged and more deeply sedated than intended. Due to its distinct pharmacological features, including a cytochrome P450-independent metabolization, intravenous lormetazepam might be clinically advantageous compared to midazolam. In this retrospective cohort study, we compared patients who received either intravenous lormetazepam or midazolam with respect to their survival and sedation characteristics. The cohort included 3314 mechanically ventilated, critically ill patients that received one of the two drugs in a tertiary medical center in Germany between 2006 and 2018. A Cox proportional hazards model with mortality as outcome and APACHE II, age, gender, and admission mode as covariates revealed a hazard ratio of 1.75 [95% CI 1.46–2.09; p < 0.001] for in-hospital mortality associated with the use of midazolam. After additionally adjusting for sedation intensity, the HR became 1.04 [95% CI 0.83–1.31; p = 0.97]. Thus, we concluded that excessive sedation occurs more frequently in critically ill patients treated with midazolam than in patients treated with lormetazepam. These findings require further investigation in prospective trials to assess if lormetazepam, due to its ability to maintain light sedation, might be favorable over other benzodiazepines for sedation in the ICU.

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The influence of leprosy-related clinical and epidemiological variables in the occurrence and severity of COVID-19: A prospective real-world cohort study

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0009635 ◽

2021 ◽

Vol 15 (7) ◽

pp. e0009635

Author(s):

Selma Regina Penha Silva Cerqueira ◽

Patrícia Duarte Deps ◽

Débora Vilela Cunha ◽

Natanael Victor Furtunato Bezerra ◽

Daniel Holanda Barroso ◽

...

Keyword(s):

Cohort Study ◽

Real World ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Significant Risk ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Protective Effects ◽

Bcg Vaccination ◽

Patients At Risk

Background Protective effects of Bacillus Calmette–Guérin (BCG) vaccination and clofazimine and dapsone treatment against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been reported. Patients at risk for leprosy represent an interesting model for assessing the effects of these therapies on the occurrence and severity of coronavirus disease 2019 (COVID-19). We assessed the influence of leprosy-related variables in the occurrence and severity of COVID-19. Methodology/Principal findings We performed a 14-month prospective real-world cohort study in which the main risk factor was 2 previous vaccinations with BCG and the main outcome was COVID-19 detection by reverse transcription polymerase chain reaction (RT-PCR). A Cox proportional hazards model was used. Among the 406 included patients, 113 were diagnosed with leprosy. During follow-up, 69 (16.99%) patients contracted COVID-19. Survival analysis showed that leprosy was associated with COVID-19 (p<0.001), but multivariate analysis showed that only COVID-19-positive household contacts (hazard ratio (HR) = 8.04; 95% CI = 4.93–13.11) and diabetes mellitus (HR = 2.06; 95% CI = 1.04–4.06) were significant risk factors for COVID-19. Conclusions/Significance Leprosy patients are vulnerable to COVID-19 because they have more frequent contact with SARS-CoV-2-infected patients, possibly due to social and economic limitations. Our model showed that the use of corticosteroids, thalidomide, pentoxifylline, clofazimine, or dapsone or BCG vaccination did not affect the occurrence or severity of COVID-19.

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Abstract P390: Relationship between BMI and Risk of Hypertension in an urban Japanese cohort study: the Suita study

Circulation ◽

10.1161/circ.129.suppl_1.p390 ◽

2014 ◽

Vol 129 (suppl_1) ◽

Author(s):

Michikazu Nakai ◽

Makoto Watanabe ◽

Kunihiro Nishimura ◽

Misa Takegami ◽

Yoshihiro Kokubo ◽

...

Keyword(s):

Cohort Study ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Population Based ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Men And Women ◽

Japanese Cohort ◽

Hazards Model ◽

Increased Risk

Objective: The positive relation between body mass index (BMI) and risk of incident hypertension (HT) has been reported mainly in the Western subjects with high BMI. However, there are a few reports in the Asian with relatively lower BMI. This study investigated the relation of BMI with risk of incident HT in the population-based prospective cohort study of Japan, the Suita study. Methods: Participants who had no HT at baseline (1,591 men and 1,973 women) aged 30-84 years were included in this study. BMI categories were defined as following: underweight (BMI<18.5), normal (18.5≤BMI<25.0), and overweight (BMI ≥ 25.0). The Cox proportional hazards model was used to estimate hazard ratios (HRs) of BMI categories for incident HT by sex. HRs were adjusted for age, cigarette smoking and alcohol drinking. The HRs according to quartiles of BMI were also estimated, using the lowest quartile of BMI as a reference. Results: During median follow-up of 7.2 years, 1,325 participants (640 men and 685 women) developed HT. The HR (95% CI) of 1kg/m2 increment of BMI for HT in men and women was 1.08 (1.05-1.11) and 1.10 (1.07-1.12), respectively. When we set a normal BMI as a reference, HR of overweight BMI in men and women was 1.37 (1.13-1.67) and 1.45 (1.18-1.77), whereas HR of underweight BMI in men and women was 0.63 (0.45-0.90) and 0.60 (0.45-0.80), respectively. In addition, compared to the lowest quartile, HR of the highest quartile of BMI in men and women was 1.67 (1.33-2.10, trend p<0.001) and 2.10 (1.67-2.64, trend p<0.001), respectively. Conclusion: In this study, we showed that higher BMI was associated with increased risk of hypertension in both Japanese men and women.

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Cause-Specific Survival for Women Diagnosed With Cancer During Pregnancy or Lactation: A Registry-Based Cohort Study

Journal of Clinical Oncology ◽

10.1200/jco.2008.17.4110 ◽

2009 ◽

Vol 27 (1) ◽

pp. 45-51 ◽

Cited By ~ 272

Author(s):

Hanne Stensheim ◽

Bjørn Møller ◽

Tini van Dijk ◽

Sophie D. Fosså

Keyword(s):

Ovarian Cancer ◽

Cohort Study ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Population Based ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Birth Registry ◽

Increased Risk ◽

Cause Specific Survival

Purpose To assess if cancers diagnosed during pregnancy or lactation are associated with increased risk of cause-specific death. Patients and Methods In this population-based cohort study using data from the Cancer Registry and the Medical Birth Registry of Norway, 42,511 women, age 16 to 49 years and diagnosed with cancer from 1967 to 2002, were eligible. They were grouped as not pregnant (reference), pregnant, or lactating at diagnosis. Cause-specific survival for all sites combined, and for the most frequent malignancies, was investigated using a Cox proportional hazards model. An additional analysis with time-dependent covariates was performed for comparison of women with and without a postcancer pregnancy. The multivariate analyses were adjusted for age at diagnosis, extent of disease, and diagnostic periods. Results For all sites combined, no intergroup differences in cause-specific death were seen, with hazard ratio (HR) of 1.03 (95% CI, 0.86 to 1.22) and HR 1.02 (95% CI, 0.86 to 1.22) for the pregnant and lactating groups, respectively. Patients with breast (HR, 1.95; 95% CI, 1.36 to 2.78) and ovarian cancer (HR, 2.23; 95% CI, 1.05 to 4.73) diagnosed during lactation had an increased risk of cause-specific death. Diagnosis of malignant melanoma during pregnancy slightly increased this risk. For all sites combined, the risk of cause-specific death was significantly decreased for women who had postcancer pregnancies. Conclusion In general, the diagnosis of most cancer types during pregnancy or lactation does not increase the risk of cause-specific death. Breast and ovarian cancer diagnosed during lactation represents an exception. We confirmed the “healthy mother effect” for women with a postcancer pregnancy.

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Risk of pleural empyema in patients with schizophrenia: a nationwide propensity-matched cohort study in Taiwan

BMJ Open ◽

10.1136/bmjopen-2017-021187 ◽

2018 ◽

Vol 8 (7) ◽

pp. e021187 ◽

Cited By ~ 5

Author(s):

Te-Chun Shen ◽

Chia-Hung Chen ◽

Yu-Jhen Huang ◽

Cheng-Li Lin ◽

Ting-Chang Chang ◽

...

Keyword(s):

Cohort Study ◽

Propensity Scores ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Pleural Empyema ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Research Database ◽

Increased Risk ◽

Comparison Cohort

ObjectiveThoracic infection and pneumonia are prevalent in patients with schizophrenia; however, it is unclear whether patients with schizophrenia are at an increased risk of developing pleural empyema.DesignA retrospective cohort study with propensity-matched cohorts with and without schizophrenia.SettingUsing the National Health Insurance Research Database of Taiwan.ParticipantsWe identified 55 888 patients with schizophrenia newly diagnosed in 2000–2011 and same number of individuals without schizophrenia as the comparison cohort, frequency matched by propensity scores estimated using age, sex, occupation, income, urbanisation, year of diagnosis and comorbidities.Primary outcome measuresWe assessed incident pleural empyema by the end of 2011 and used the Cox proportional hazards model to calculate the schizophrenia cohort to comparison cohort HR of pleural empyema.ResultsThe overall incidence of pleural empyema was 2.44-fold greater in the schizophrenia cohort than in the comparison cohort (4.39vs1.80 per 10 000 person-years), with an adjusted HR of 2.87(95% CI 2.14 to 3.84). Stratified analyses by age, sex, occupation, income, urbanisation and comorbidity revealed significant hazards for pleural empyema associated with schizophrenia in all subgroups.ConclusionsPatients with schizophrenia are at an increased risk of developing pleural empyema and require greater attention and appropriate support.

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Laxative use and mortality in patients on haemodialysis: a prospective cohort study

BMC Nephrology ◽

10.1186/s12882-021-02572-y ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Yu Honda ◽

Seiji Itano ◽

Aiko Kugimiya ◽

Eiji Kubo ◽

Yosuke Yamada ◽

...

Keyword(s):

Cohort Study ◽

Missing Values ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Risk Of Death ◽

Number Of Patients ◽

Increased Risk ◽

All Cause Mortality

Abstract Background Patients on haemodialysis (HD) are often constipated. This study aimed to assess the relationship between constipation and mortality in such patients. In this study, constipation was defined as receiving prescription laxatives, based on the investigation results of “a need to take laxatives is the most common conception of constipation” reported by the World Gastroenterology Organization Global Guidelines. Methods This cohort study included 12,217 adult patients on HD enrolled in the Japan-Dialysis Outcomes and Practice Patterns study phases 1 to 5 (1998 to 2015). The participants were grouped into two based on whether they were prescribed laxatives during enrolment at baseline. The primary endpoint was all-cause mortality in 3 years, and the secondary endpoint was cause-specific death. Missing values were imputed using multiple imputation methods. All estimations were calculated using a Cox proportional hazards model with an inverse probability of treatment weighting using the propensity score. Results Laxatives were prescribed in 30.5% of the patients, and there were 1240 all-cause deaths. There was a significant association between laxative prescription and all-cause mortality [adjusted hazard ratio (AHR), 1.12; 95% confidence interval (CI): 1.03 to 1.21]. Because the Kaplan-Meier curves of the two groups crossed over, we examined 8345 patients observed for more than 1.5 years. Laxative prescription was significantly associated with all-cause mortality (AHR, 1.35; 95% CI: 1.17 to 1.55). The AHR of infectious death was 1.62 (95% CI: 1.14 to 2.29), and that of cancerous death was 1.60 (95% CI: 1.08 to 2.36). However, cardiovascular death did not show a significant inter-group difference. Conclusions Constipation requiring use of laxatives was associated with an increased risk of death in patients on HD. It is important to prevent patients receiving HD from developing constipation and to reduce the number of patients requiring laxatives.

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