Experience of cohort formation and data collection in a retrospective cohort epidemiological study

2021 ◽  
Vol 61 (4) ◽  
pp. 253-266
Author(s):  
Evgeny V. Kovalevskiy ◽  
Joachim Schüz ◽  
Igor V. Bukhtiyarov ◽  
Sergey V. Kashanskiy
Keyword(s):  
Retrospective Cohort ◽  
Malignant Neoplasms ◽  
Chrysotile Asbestos ◽  
Asbestos Fibers ◽  
The World ◽  
Occupationally Exposed ◽  
The Mean ◽  
One Year ◽  
Observation Period

A retrospective cohort study was carried out to investigate the mortality of workers occupationally exposed to dust containing chrysotile asbestos fibers. In its chemical and physical properties, it differs from the fibers of other types of asbestos and is the only type of asbestos that is currently approved for use in many countries of the world. The members of the cohort are current and former employees who have worked for at least one year at the production sites of the complex of enterprises for the mining and enrichment of chrysotile asbestos (JSC "Uralasbest", Asbest, Sverdlovsk region) in the period from 01.01.1975 to 31.12.2010. Of the 35,837 members of the cohort, 12,729 (35.5%) people died (2,373 of them were malignant neoplasms of various localizations, including 10 mesotheliomas), 18,799 (52.5%) were alive at the end of the observation period (2015), and 4,309 people (12.0%) were censored by the end of 2015. The mean follow-up period was 21.7 years for men and 25.9 years for women. The average age at death was 59.4 years for men and 66.5 years for women. It is currently the world's largest cohort of workers in the field.

COMPARATIVE EVALUATION OF THE CAUSES OF DEATH IN A COHORT OF WORKERS IN THE MINING AND ENRICHMENT OF CHRYSOTILE ASBESTOS

2021 ◽  
Author(s):  
E.V. Kovalevskiy ◽  
◽  
J. Schüz ◽  
S.V. Kashanskiy ◽  
◽  
...  
Keyword(s):  
Comparative Evaluation ◽  
Causes Of Death ◽  
Malignant Neoplasms ◽  
Chrysotile Asbestos ◽  
Asbestos Fibers ◽  
Occupationally Exposed ◽  
The Mean ◽  
One Year ◽  
Observation Period

Abstract. A retrospective cohort study was carried out to investigate the mortality of workers occupationally exposed to dust containing chrysotile asbestos fibers. In its chemical and physical properties, it differs from the fibers of other types of asbestos and is the only type of asbestos that is currently approved for use in many countries of the world. The members of the cohort are current and former employees who have worked for at least one year at the production sites of the complex of enterprises for the mining and enrichment of chrysotile asbestos (JSC «Uralasbest», Asbest, Sverdlovsk region) in the period from 01.01.1975 to 31.12.2010. Of the 35837 members of the cohort, 12729 (35.5%) people died (2373 of them were malignant neoplasms of various localizations, including 10 mesotheliomas), 18799 (52.5%) were alive at the end of the observation period (2015), and 4309 people (12.0%) were censored by the end of 2015. The mean follow-up period was 21.7 years for men and 25.9 years for women. The average age at death was 59.4 years for men and 66.5 years for women. This paper presents a general comparative evaluation of the causes of death of cohort members. Further processing of data obtained is currently underway.

HRA Model for Hypercholesterolemia Based on a Longitudinal Health Database

1998 ◽  
Vol 37 (02) ◽  
pp. 130-133
Author(s):  
T. Kishimoto ◽  
Y. Iida ◽  
K. Yoshida ◽  
M. Miyakawa ◽  
H. Sugimori ◽  
...  
Keyword(s):  
Total Cholesterol ◽  
Proportional Hazards ◽  
Proportional Hazards Model ◽  
Model Analysis ◽  
Serum Total Cholesterol ◽  
Hazards Model ◽  
The Mean ◽  
Health Database ◽  
Observation Period

AbstractTo evaluate the risk factors for hypercholesterolemia, we examined 4,371 subjects (3,207 males and 1,164 females) who received medical checkups more than twice at an AMHTS in Tokyo during the period from 1976 through 1991; and whose serum total cholesterol was under 250 mg/dl. The mean follow-up duration was 6.6 years. A self-registering questionnaire was administered at the time of the health checkup. The endpoint of this study was the onset of hypercholesterolemia when the level of serum total cholesterol was 250 mg/dl and over. We compared two prognosis groups (normal and hypercholesterol) in terms of age, examination findings and lifestyle. After assessing each variable, we employed Cox's proportional hazards model analysis to determine the factors related to the occurrence of hypercholesterolemia. According to proportional hazards model analysis, total cholesterol, triglyceride and smoking at the beginning, and hypertension during the observation period were selected in males; and total cholesterol at the beginning and age were selected in females to determine the factors related to the occurrence of hypercholesterolemia.

Vitamin D Level Stability in Dystrophinopathy Patients on Vitamin D Supplementation

2021 ◽  
pp. 1-7
Author(s):  
Naomi Vather-Wu ◽  
Matthew D. Krasowski ◽  
Katherine D. Mathews ◽  
Amal Shibli-Rahhal
Keyword(s):  
Vitamin D ◽  
Retrospective Cohort ◽  
Vitamin D Supplementation ◽  
Hydroxyvitamin D ◽  
Frequent Monitoring ◽  
25 Hydroxyvitamin D ◽  
The Mean ◽  
Stable Maintenance ◽  
Mean Time

Background: Expert guidelines recommend annual monitoring of 25-hydroxyvitamin D (25-OHD) and maintaining 25-OHD ≥30 ng/ml in patients with dystrophinopathies. Objective: We hypothesized that 25-OHD remains stable and requires less frequent monitoring in patients taking stable maintenance doses of vitamin D. Methods: We performed a retrospective cohort study, using the electronic health record to identify 26 patients with dystrophinopathies with a baseline 25-OHD ≥30 ng/mL and at least one additional 25-OHD measurement. These patients had received a stable dose of vitamin D for ≥3 months prior to their baseline 25-OHD measurement and throughout follow-up. The main outcome measured was the mean duration time the subjects spent with a 25-OHD ≥30 ng/mL. Results: Only 19% of patients dropped their 25-OHD to <  30 ng/ml, with a mean time to drop of 33 months and a median nadir 25-OHD of 28 ng/mL. Conclusions: These results suggest that measurement of 25-OHD every 2–2.5 years may be sufficient in patients with a baseline 25-OHD ≥30 ng/mL and who are on a stable maintenance dose of vitamin D. Other patients may require more frequent assessments.

scholarly journals Complications in Mandibular Midline Distraction

2017 ◽  
Vol 10 (3) ◽  
pp. 204-207 ◽  
Author(s):  
Jan Pieter de Gijt ◽  
Atilla Gül ◽  
Eppo B. Wolvius ◽  
Karel G.H. van der Wal ◽  
Maarten J. Koudstaal
Keyword(s):  
Retrospective Cohort ◽  
Mental Nerve ◽  
Safe Method ◽  
Congenital Deformities ◽  
Area Of Interest ◽  
Sensory Disturbances ◽  
History Of ◽  
The Mean ◽  
New Surgical Technique

Mandibular midline distraction (MMD) is a relatively new surgical technique for correction of transverse discrepancies of the mandible. This study assesses the amount and burden of complications in MMD. A retrospective cohort study was performed on patients who underwent MMD between 2002 and 2014. Patients with congenital deformities or a history of radiation therapy in the area of interest were excluded. Patient records were obtained and individually assessed for any complications. Complications were graded using the Clavien-Dindo classification system (CDS). Seventy-three patients were included of which 33 were males and 40 were females. The mean follow-up was 2.1 years. Twenty-nine patients had minor complications, grades I and II. Two patients had a grade IIIa and three patients had a grade IIIb complication. Common complications were pressure ulcers, dehiscence, and (transient) sensory disturbances of the mental nerve. This study shows that although MMD is a relatively safe method, complications can occur. Mostly the complications are mild, transient, and manageable without the need for any reoperation.

scholarly journals Effect of phacoemulsification with intraocular lens implantation in eyes with cataract and functioning filtering blebs

2013 ◽  
Vol 13 (2) ◽  
pp. 33-41
Author(s):  
Devendra Maheshwari ◽  
Rengappa Ramakrishanan ◽  
Mohideen Abdul Kader ◽  
Neelam Pawar ◽  
Ankit Gupta
Keyword(s):  
Visual Acuity ◽  
Intraocular Pressure ◽  
Intraocular Lens ◽  
Intraocular Lens Implantation ◽  
Corrected Visual Acuity ◽  
Lens Implantation ◽  
The Mean ◽  
One Year ◽  
Best Corrected Visual Acuity

Aim: To evaluate the effect of phacoemulsification with intraocular lens implantation in eyes with pre-existing trabeculectomy.Methods: This prospective single-center clinical study evaluated intraocular pressure in 60 eyes of 60 patients who underwent phacoemulsification and implantation of a foldable intraocular lens after a previous successful trabeculectomy. Patients who had a trabeculectomy more than one year prior to the study were included. Intraocular pressure, number of antiglaucoma medications, bleb appearance, and visual acuity were recorded preoperatively, and at each follow-up examination and 12 months after phacoemulsification.Results: The mean intraocular pressure before phacoemulsification was 12.42 mmHg (SD, 4.60 mmHg), which increased to 14.98 mmHg (SD, 4.18 mmHg), 14.47 mmHg (SD, 3.58 mmHg), 15.44 mmHg (SD, 3.60 mmHg), and 15.71 mmHg (SD, 3.47 mmHg) after one, three, six, and 12 months, respectively. At each follow-up visit, the mean IOP was significantly higher than the preoperative value (p < 0.001, p = 0.015, p ≤ 0.001, and p = 0.001 at month one, three, six, and 12, respectively). The mean preoperative best-corrected visual acuity was 0.98 logMAR (SD, 0.44 logMAR) and the mean postoperative best-corrected visual acuity at 12 months was 0.20 logMAR (SD, 0.21 logMAR) [p = 0.0001]. The mean preoperative number of antiglaucoma medications used was 0.57 (SD, 0.63), which increased to 0.65 (SD, 0.63 ), 0.70 (SD, 0.72 ) 0.68, (SD, 0.70), and 0.67 (SD, 0.77 ) at one, three, six, and 12 months, respectively, but there were no statistically significant differences. Bleb size decreased clinically after phacoemulsification. Nineteen of 60 eyes (32%) developed fibrosis of bleb with decreased bleb size.Conclusion: Phacoemulsification with intraocular lens implantation significantly increased intraocular pressure and increased the number of antiglaucoma medications in eyes with pre-existing functioning filtering blebs.

Outcomes of conbercept therapy for choroidal neovascularization secondary to pathological myopia

2021 ◽  
Vol 2 (4) ◽  
pp. 210-213
Author(s):  
Zheng-Feng Liu ◽  
◽  
Da-Dong Guo ◽  
Mei-Hua Ding ◽  
Hong-Sheng Bi ◽  
...  
Keyword(s):  
Choroidal Neovascularization ◽  
Fundus Fluorescein Angiography ◽  
Pathological Myopia ◽  
Foveal Thickness ◽  
Central Foveal Thickness ◽  
Significant Difference ◽  
Long Term Follow Up ◽  
The Mean ◽  
One Year

AIM: To evaluate the one-year outcome of intravitreal conbercept injections for the treatment of choroidal neovascularization secondary to pathological myopia (pm-CNV) by optical coherence tomography angiography (OCTA). METHODS: The medical records of 26 consecutive eyes of 23 patients who received intravitreal injections of conbercept for pm-CNV with a follow-up of one year were retrospectively reviewed. All the patients were diagnosed by fundus fluorescein angiography (FFA) and OCTA at the first visit. All approaches were performed as “1+PRN” treatment. Outcomes included best-corrected visual acuity (BCVA), central foveal thickness (CFT) and the mean CNV area by OCTA. RESULTS: Mean Logarithm BCVA improved from (0.66±0.51) at baseline to (0.39±0.38) at one year (t=3.528, P=0.004). The CFT before treatment and after one year after were 275.08±48.74) μm and (205.15±43.74) μm respectively (t=4.630, P=0.001). The mean pm-CNV areas before treatment and after one year treatment were (0.48±0.24) mm2 and (0.15±0.11) mm2 respectively, with a significant difference among them (t=5.329, P=0.000). Twenty-one eyes had no needs after the first treatment. Four eyes received 2 injections and only one eye received 3 injections. No severe adverse events were noted relevant to the therapy. CONCLUSION: Intravitreal conbercept can improve the vision and relieve CFT and CNV area for the treatment of pm-CNV with “1+PRN” by OCTA for one year, however, long-term follow-up still need to be performed.

Application of femtolaser-assisted phacoemulsification in combined pathology of cataract and glaucoma

2021 ◽  
pp. 18-21
Author(s):  
A.P. Voznyuk ◽  
◽  
S.I. Anisimov ◽  
S.Y. Anisimova ◽  
L.L. Arutyunyan ◽  
...  
Keyword(s):  
Surgical Treatment ◽  
Biomechanical Properties ◽  
Mean Values ◽  
Long Term Follow Up ◽  
The Mean ◽  
Group 2 ◽  
Observation Period ◽  
Group 1

Purpose. To evaluate the efficacy and safety of femtolaser-assisted phacoemulsification in glaucomatous eyes in the long-term follow-up. Materials and methods. A retrospective analysis of the results of the surgical treatment of patients with combined cataract and glaucoma pathology was analyzed. The patients were divided into groups depending on the method of surgical intervention: 1) phacoemulsification with femtolaser support (26 eyes, 23 patients); 2) phacoemulsification (36 eyes, 30 patients); Results. Before surgery, there were no statistically significant differences in IOP and corneal hysteresis (СН) between groups 1 and 2. The mean values of IOP cc, IOP g and СН of group 1 before surgery were 22.7±6.1 mm Hg, 20.9±6.9 mm Hg, 8.5±1.6 mm Hg; 2 group – 22.9±8.7 mm Hg, 21.6±8.9 mm Hg, 8.9±1.6 mm Hg respectively. Average values of IOP cc, IOP g and CН 5 years after the surgical treatment in group 1 were 15.3±1.2 mm Hg, 14.4±3.4 mm Hg, 9.6±4.2 mm Hg; in group 2 – 18.0±4.2 mm Hg, 16.1±4.2 mm Hg, 8.8±2.2 mm Hg respectively. In both groups, stabilization of IOP and CH indices was noted, which remained throughout the entire observation period, which shows the normalization of the biomechanical properties of the corneoscleral membrane of the eye in the long-term postoperative period. Conclusion. Femtolaser accompaniment of phacoemulsification is an effective and safe method of cataract surgery for combined pathology. Key words: femtolaser, cataract, glaucoma, phacoemulsification.

Blepharochalasis:Clinical and Epidemiological Characteristics, Surgical Strategy and Prognosis-- A Retrospective Cohort Study with 93 Cases

2021 ◽  
Author(s):  
Jinqiong Zhou ◽  
Jingwen Ding ◽  
dongmei li
Keyword(s):  
Cohort Study ◽  
Lacrimal Gland ◽  
Retrospective Cohort Study ◽  
Retrospective Cohort ◽  
Acute Attack ◽  
Surgical Strategy ◽  
Lacrimal Gland Prolapse ◽  
The Mean ◽  
Epidemiological Characteristics

Abstract Background: Blepharochalasis is a rare eyelid disorder but eventually leading to destructive eyelid deformation. Until now the clinical and epidemiological data is unavailable. This study aimed o report the manifestations, epidemiological characteristics and surgical strategy of a large series of blepharochalasis patients with long-term follow up, the prognosis of different clinical deformities was also investigated. Methods: This is a retrospective cohort study, included consecutive patients diagnosed with blepharochalasis in a single center. Blepharoplasty and other surgical approaches were scheduled according to the various manifestations, after a 2-year quiescent period with no recurrent attacks and exacerbation of lesions. Prognosis after surgery was recorded.Results: A total of 93 patients, with a mean follow-up of 5.29±2.07 (range: 3-10) years before surgery, and 2(range:1-4) years follow-up after surgery were included. Of all those 93 patients, 72.04% were females (67, P=0.02 ). The mean age of onset of blepharochalasis symptoms was 10.09±3.32 (range: 5-16) years, mostly (83.87%) consisted with the onset of the puberty. With the average of 5 times per year, the mean duration of each acute attack was 28.12±1.01 (rang: 2-192)hours. The mean duration from the onset of acute attack to the quiescent stage lasted for 7.33 ± 2.05 (range: 4-10) years. Most of the cases (88, 94.62%) had more than one manifestation at the end of the last follow-up before surgery. Ptosis (48.39%) was the most common deformity. Followed by lacrimal gland prolapse (44.09%), canthal angle deformity(29.04%), lower eyelid retraction(17.20%). After surgery, the functional and cosmetically acceptable results were achieved in all patients except for overcorrection in 5 (11.90%) patients with ptosis. The lacrimal gland prolapse recurred in two (4.00%) patients at 29 and 36 months after surgery. Conclusions: Blepharochalasis is rare but mostly occurred in adolescent females. The process from the onset to the stable stage usually lasted for about 7 years, might be associated with the onset of puberty. Surgical management of clinical manifestations after at least 2-year follow-up period of quiescence would be appropriate in order to observe a great plastic effect, low overcorrection and recurrence rate.

scholarly journals An Epidemic of Primary Tuberculosis in a Canadian Aboriginal Community

1991 ◽  
Vol 2 (4) ◽  
pp. 133-141 ◽  
Author(s):  
Manuel W Mah ◽  
Elizabeth Anne Fanning
Keyword(s):  
Positive Skin ◽  
Aboriginal Community ◽  
Primary Tuberculosis ◽  
Delay In Diagnosis ◽  
The Family ◽  
Source Case ◽  
The Mean ◽  
One Year ◽  
Isoniazid Prophylaxis

In 1987, an outbreak of primary tuberculosis occurred in a Canadian aboriginal community of 350 people. The source case was a young woman who had been symptomatic for four months with smear positive cavitary pulmonary tuberculosis. Her 17 siblings and their families were frequent close contacts. Among the 626 persons surveyed in the community and environs, 35 additional active cases of tuberculosis were identified. The mean age of cases was 13 years and the median age 10 years. The method of diagnosis was bacteriological in 20 and radiological in 16. There were 257 positive tuberculin reactors of whom 120 had no previous record of a positive skin test. Isoniazid prophylaxis was recommended to all new reactors, close household contacts, reactors under the age of 35 years and reactors with lung scars. One late case was identified at one year of follow-up in a contact who had refused prophylaxis. The rates of infection and disease were higher in the family (65% and 46%, respectively) than in the community and environs (19% and 5.6%, respectively). This report illustrates the nature of a point source epidemic of primary tuberculosis in a susceptible community with a predictable reservoir of infection. The delay in diagnosis of the source case allowed numerous new infections to occur. However, prompt aggressive contact follow-up was successful in containing the epidemic. To prevent future outbreaks, the reservoir of infected persons must be identified and administered chemoprophylaxis.

482Direct oral anticoagulant rivaroxaban in very old and frail patients: A one-year prospective follow-up of a large-scale cohort (SAFIR-AC)

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
O Hanon ◽  
J Vidal ◽  
E Chaussade ◽  
J P David ◽  
N Boulloche ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Major Bleeding ◽  
Large Scale ◽  
Bleeding Risk ◽  
Geriatric Population ◽  
Very Old ◽  
The Mean ◽  
One Year ◽  
The One

Abstract Background/Introduction Age is one of the strongest predictors/risk factors for ischemic stroke in subjects with atrial fibrillation (AF). Direct oral anticoagulants (DOACs) have been shown to be effective in the prevention of this condition; however, clinical evidence on bleeding risk with this therapeutic strategy in very old and frail geriatric patients is poor. Purpose To assess bleeding risk in French geriatric patients aged ≥80 years and diagnosed with AF newly treated with rivaroxaban. Methods Subjects, presenting to one of 33 geriatric centers, with non-valvular AF and recent initiation of a treatment with rivaroxaban were enrolled in the study and followed-up every 3 months for 12 months. Clinical and routine laboratory data and evaluation scores, such as HAS-BLED, HEMORR2HAGES, ATRIA, and CHA2DS2-VASc, as well as comprehensive geriatric evaluation were reported. Major bleeding, as defined in ROCKET AF study, was reported at each visit, and this primary outcome was adjudicated by an independent committee. Results of this cohort were compared with findings from a similar cohort treated with vitamin K antagonists (VKAs) from the same centers (n=924). Results A total of 1045 subjects were enrolled in the study of whom 995 (95%) had a one-year follow-up (analyzed population). The mean (standard deviation (SD)) age was 86.0 (4.3) years, with the majority of patients being female (61%), 23% aged 90 years or older, and 48% having an estimated glomerular filtration rate (eGFR) <50 mL/min. The main comorbidities were hypertension in 77% of subjects, malnutrition 49%, anemia 43%, dementia 39%, heart failure 36%, and falls 27%. The mean (SD) score for CHA2DS2-VASc was 4.8 (1.4), HAS-BLED 2.4 (0.9), Mini-Mental State Examination (MMSE) 21.5 (6.9), Activities of Daily Living (ADL) 4.4 (1.9), and Charlson Comorbidity Index 6.7 (2.0). The one-year rate of major bleeding events was 6.4% of which 0.8% were fatal and 1.1% intracranial hemorrhages (ICH), whereas the one-year rate of ischemic stroke was 1.4% and all-cause mortality 17.9%. Computed with VKA cohort findings and adjusted for age, gender, eGFR and Charlson score, this would result in a hazard ratio of 0.54 (95% confidence interval [CI], 0.38 to 0.78) for major bleeding, 0.36 (0.17 to 0.76) for ICH, 0.62 (0.29 to 1.33) for ischemic stroke, and 0.82 (0.65 to 1.02) for all-cause mortality, in favor of rivaroxaban. Conclusions This is the first large-scale prospective study in geriatric population in AF subjects treated with DOAC (rivaroxaban) Major bleeding risk appeared higher in very old than younger population, however major bleeding and ICH rates were significantly lower with rivaroxaban than with VKAs when used in the same geriatric population. This study indicates that Rivaroxaban can be used in very old and frail patients for the treatment of non-valvular AF. Acknowledgement/Funding Unrestricted grant from Bayer

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