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Dive into the research topics where Irina Tolstykh is active.

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Featured researches published by Irina Tolstykh.


The American Journal of Medicine | 2008

COPD as a systemic disease: impact on physical functional limitations.

Mark D. Eisner; Paul D. Blanc; Edward H. Yelin; Stephen Sidney; Patricia P. Katz; Lynn Ackerson; Phenius V. Lathon; Irina Tolstykh; Theodore A. Omachi; Nancy N. Byl; Carlos Iribarren

PURPOSE Although chronic obstructive pulmonary disease (COPD) has a major impact on physical health, the specific impact of COPD on physical functional limitations has not been characterized clearly. We aimed to elucidate the physical functional limitations that are directly attributable to COPD compared to a matched referent group without the condition. METHODS We used the Function, Living, Outcomes, and Work (FLOW) cohort study of adults with COPD (n=1202) and referent subjects matched by age, sex, and race (n=302) to study the impact of COPD on the risk of a broad array of functional limitations using validated measures: lower extremity function (Short Physical Performance Battery [SPPB]), submaximal exercise performance (Six Minute Walk Test [SMWT]), standing balance (Functional Reach Test), skeletal muscle strength (manual muscle testing with dynamometry), and self-reported functional limitation (standardized item battery). Multivariate analysis was used to control for confounding by age, sex, race, height, educational attainment, and cigarette smoking. RESULTS COPD was associated with poorer lower extremity function (mean SPPB score decrement for COPD vs referent -1.0 points; 95% CI, -1.25 to -0.73 pts) and less distance walked during the SMWT (-334 feet; 95% CI, -384 to -282 ft). COPD also was associated with weaker muscle strength in every muscle group tested, including both the upper and lower extremities (P<.0001 in all cases) and with a greater risk of self-reported functional limitation (OR 6.4; 95% CI, 3.7 to 10.9). CONCLUSIONS A broad array of physical functional limitations were specifically attributable to COPD. COPD affects a multitude of body systems remote from the lung.


Respiratory Research | 2007

Body composition and functional limitation in COPD.

Mark D. Eisner; Paul D. Blanc; Steve Sidney; Edward H. Yelin; Phenius V. Lathon; Patricia P. Katz; Irina Tolstykh; Lynn Ackerson; Carlos Iribarren

BackgroundLow body mass index has been associated with increased mortality in severe COPD. The impact of body composition earlier in the disease remains unclear. We studied the impact of body composition on the risk of functional limitation in COPD.MethodsWe used bioelectrical impedance to estimate body composition in a cohort of 355 younger adults with COPD who had a broad spectrum of severity.ResultsAmong women, a higher lean-to-fat ratio was associated with a lower risk of self-reported functional limitation after controlling for age, height, pulmonary function impairment, race, education, and smoking history (OR 0.45 per 0.50 increment in lean-to-fat ratio; 95% CI 0.28 to 0.74). Among men, a higher lean-to-fat ratio was associated with a greater distance walked in 6 minutes (mean difference 40 meters per 0.50 ratio increment; 95% CI 9 to 71 meters). In women, the lean-to-fat ratio was associated with an even greater distance walked (mean difference 162 meters per 0.50 increment; 95% CI 97 to 228 meters). In women, higher lean-to-fat ratio was also associated with better Short Physical Performance Battery Scores. In further analysis, the accumulation of greater fat mass, and not the loss of lean mass, was most strongly associated with functional limitation among both sexes.ConclusionBody composition is an important non-pulmonary impairment that modulates the risk of functional limitation in COPD, even after taking pulmonary function into account. Body composition abnormalities may represent an important area for screening and preventive intervention in COPD.


Journal of Epidemiology and Community Health | 2011

Socioeconomic status, race and COPD health outcomes

Mark D. Eisner; Paul D. Blanc; Theodore A. Omachi; Edward H. Yelin; Stephen Sidney; Patricia P. Katz; Lynn Ackerson; Gabriela Sanchez; Irina Tolstykh; Carlos Iribarren

Background Although chronic obstructive pulmonary disease (COPD) is a common cause of death and disability, little is known about the effects of socioeconomic status (SES) and race–ethnicity on health outcomes. Methods The aim of this study is to determine the independent impacts of SES and race–ethnicity on COPD severity status, functional limitations and acute exacerbations of COPD among patients with access to healthcare. Data were used from the Function, Living, Outcomes and Work cohort study of 1202 Kaiser Permanente Northern California Medical Care Plan members with COPD. Results Lower educational attainment and household income were consistently related to greater disease severity, poorer lung function and greater physical functional limitations in cross-sectional analysis. Black race was associated with greater COPD severity, but these differences were no longer apparent after controlling for SES variables and other covariates (comorbidities, smoking, body mass index and occupational exposures). Lower education and lower income were independently related to a greater prospective risk of acute COPD exacerbation (HR 1.5; 95% CI 1.01 to 2.1; and HR 2.1; 95% CI 1.4 to 3.4, respectively). Conclusion Low SES is a risk factor for a broad array of adverse COPD health outcomes. Clinicians and disease management programs should consider SES as a key patient-level marker of risk for poor outcomes.


American Journal of Epidemiology | 2012

Adult Asthma and Risk of Coronary Heart Disease, Cerebrovascular Disease, and Heart Failure: A Prospective Study of 2 Matched Cohorts

Carlos Iribarren; Irina Tolstykh; Mary K. Miller; Erica Sobel; Mark D. Eisner

Asthma has been associated with increased cardiovascular disease (CVD) risk. The authors ascertained the association of asthma with CVD and the roles that sex, concurrent allergy, and asthma medications may play in this association. They assembled a cohort of 203,595 Northern California adults with asthma and a parallel asthma-free referent cohort (matched 1:1 on age, sex, and race/ethnicity); both cohorts were followed for incident nonfatal or fatal CVD and all-cause mortality from January 1, 1996, through December 31, 2008. Each cohort was 66% female and 47% white. After adjustment for age, sex, race/ethnicity, cardiac risk factors, and comorbid allergy, asthma was associated with a 1.40-fold (95% confidence interval (CI): 1.35, 1.45) increased hazard of coronary heart disease, a 1.20-fold (95% CI: 1.15, 1.25) hazard of cerebrovascular disease, a 2.14-fold (95% CI: 2.06, 2.22) hazard of heart failure, and a 3.28-fold (95% CI: 3.15, 3.41) hazard of all-cause mortality. Stronger associations were noted among women. Comorbid allergy predicted CVD but did not synergistically increase the CVD risk associated with asthma. Only asthma patients using asthma medications (particularly those on oral corticosteroids alone or in combination) were at enhanced risk of CVD. In conclusion, asthma was prospectively associated with increased risk of major CVD. Modifying effects were noted for sex and asthma medication use but not for comorbid allergy.


Journal of Womens Health | 2004

Breast Vascular Calcification and Risk of Coronary Heart Disease, Stroke, and Heart Failure

Carlos Iribarren; Alan S. Go; Irina Tolstykh; Stephen Sidney; S. Claiborne Johnston; David B. Spring

OBJECTIVE Vascular calcification holds promise as a useful cardiovascular risk maker. Our objective was to examine the association between breast vascular calcification and risk of cardiovascular disease (CVD) outcomes. METHODS A cohort study was performed among 12,761 women, 40-79 years of age at baseline (1968-1973), who attended multiphasic health checkups that included mammography. The outcome measures included coronary heart disease (CHD), ischemic stroke, transient ischemic attack (TIA), hemorrhagic stroke, and heart failure, ascertained using discharge diagnosis codes and death records through December 31, 2000 (median follow-up, 24.8 years). RESULTS Breast vascular calcification was present in 424 (3%) women. It was independently and positively associated with age, high parity, and diabetes and inversely associated with education level and current cigarette smoking. After adjustment for age, education level, race, cigarette smoking, alcohol use, body mass index (BMI), serum total cholesterol, hypertension, diabetes, parental history of myocardial infarction (MI), parity, and hormone replacement therapy (HRT), breast vascular calcification was associated with a 1.32-fold increased risk of CHD (95% confidence interval [CI] 1.08-1.60), a 1.41-fold increased risk of ischemic stroke (95% CI 1.11-1.78), and a 1.52-fold increased risk of heart failure (95% CI 1.18-1.98). CONCLUSIONS Breast vascular calcification detected as part of a screening mammogram was an independent risk factor for multiple cardiovascular outcomes among women. The value of mammography in cardiovascular risk stratification deserves further investigation.


Osteoarthritis and Cartilage | 2010

Pre-radiographic MRI findings are associated with onset of knee symptoms: the most study

M K Javaid; J.A. Lynch; Irina Tolstykh; Ali Guermazi; Frank W. Roemer; Piran Aliabadi; Charles E. McCulloch; Jeffrey R. Curtis; David T. Felson; Nancy E. Lane; J Torner; Michael C. Nevitt

OBJECTIVE Magnetic resonance imaging (MRI) has greater sensitivity to detect osteoarthritis (OA) damage than radiographs but it is uncertain which MRI findings in early OA are clinically important. We examined MRI abnormalities detected in knees without radiographic OA and their association with incident knee symptoms. METHOD Participants from the Multicenter Osteoarthritis Study (MOST) without frequent knee symptoms (FKS) at baseline were eligible if they also lacked radiographic features of OA at baseline. At 15 months, knees that developed FKS were defined as cases while control knees were drawn from those that remained without FKS. Baseline MRIs were scored at each subregion for cartilage lesions (CARTs); osteophytes (OST); bone marrow lesions (BML) and cysts. We compared cases and controls using marginal logistic regression models, adjusting for age, gender, race, body mass index (BMI), previous injury and clinic site. RESULTS 36 case knees and 128 control knees were analyzed. MRI damage was common in both cases and controls. The presence of a severe CART (P=0.03), BML (P=0.02) or OST (P=0.02) in the whole knee joint was more common in cases while subchondral cysts did not differ significantly between cases and controls (P>0.1). Case status at 15 months was predicted by baseline damage at only two locations; a BML in the lateral patella (P=0.047) and at the tibial subspinous subregions (P=0.01). CONCLUSION In knees without significant symptoms or radiographic features of OA, MRI lesions of OA in only a few specific locations preceded onset of clinical symptoms and suggest that changes in bone play a role in the early development of knee pain. Confirmation of these findings in other prospective studies of knee OA is warranted.


Social Science & Medicine | 2008

Community-level social capital and recurrence of acute coronary syndrome

Richard M. Scheffler; Timothy T. Brown; Leonard Syme; Ichiro Kawachi; Irina Tolstykh; Carlos Iribarren

Social capital has been shown to be associated with reduced mortality due to cardiovascular disease. Our aim was to determine the association of time-varying community-level social capital (CSC) with recurrence of acute coronary syndrome using a retrospective cohort study design. A total of 34,752 men and women were identified, aged 30-85 years, who were hospitalized for acute coronary syndrome between January 1, 1998 and December 31, 2002 in Kaiser Permanente Northern California, USA, an integrated health care delivery system. The primary outcome was recurrent non-fatal or fatal acute coronary syndrome; median follow-up was 19 months. We estimated random-effects, three-level Cox proportional hazard models adjusting for sex, age, race/ethnicity, comorbidities, medication use, and revascularization procedures at level 1, median household income for the census block-group at level 2, and income inequality, racial/ethnic concentration, penetration of health maintenance organizations, and CSC at level 3. Our measure of CSC was the previously validated Petris Social Capital Index (PSCI). We found that a one-standard deviation increase in the PSCI, after adjusting for the above covariates, was significantly associated with decreased recurrence of acute coronary syndrome only for those living in areas where block-group level median household income was below the grand median compared to those living in areas where block-group level median household income was at the grand median or above. These results suggest that community-level social capital may be negatively associated with recurrence of acute coronary syndrome among lower-income individuals.


Annals of Allergy Asthma & Immunology | 2010

Asthma and the prospective risk of anaphylactic shock and other allergy diagnoses in a large integrated health care delivery system

Carlos Iribarren; Irina Tolstykh; Mary K. Miller; Mark D. Eisner

BACKGROUND The association between asthma and anaphylaxis remains poorly understood. OBJECTIVE To ascertain, in a managed care organization in northern California, the association of asthma and asthma severity with future risk of anaphylactic shock and other selected allergy diagnoses. METHODS Using electronic data and validated algorithms, we assembled a cohort of 526,406 patients who met the criteria for asthma between 1996 and 2006 and a referent cohort (with no utilization for asthma) individually matched on age, sex, and race/ethnicity. In each cohort, 54% of patients were female and 55% were white; their mean (SD) age was 24 (20) years. The main outcome measures were anaphylactic shock (caused by an adverse food reaction, caused by serum, or other/idiopathic), allergic urticaria, anaphylaxis after sting(s), and angioedema. RESULTS The incidence of anaphylactic shock was 109.0 per 100,000 person-years in the asthma cohort and 19.9 per 100,000 person-years in the referent cohort. After adjustment for age, sex, race/ethnicity, comorbidities, and immunotherapy, asthma was associated with a 5.2-fold (95% confidence interval, 4.7- to 5.6-fold) increased hazard of anaphylactic shock. Asthma was also significantly associated with an increased risk of the 3 selected allergy diagnoses, with hazard ratios of 1.4 to 1.9. A significant trend by severity of asthma was apparent for food-related and other/idiopathic anaphylactic shock and for anaphylaxis after sting(s). CONCLUSIONS In this insured population, asthma was prospectively associated with increased risk of anaphylactic shock and other allergy diagnoses. However, the effect of asthma severity was not consistent across outcome measures.


Annals of Allergy Asthma & Immunology | 2008

Risk factors for death in adults with severe asthma

Theodore A. Omachi; Carlos Iribarren; Urmimala Sarkar; Irina Tolstykh; Edward H. Yelin; Paul D. Blanc; Mark D. Eisner; Patricia P. Katz

BACKGROUND Mortality risk in adult asthma is poorly understood, especially the interplay among race, disease severity, and health care access. OBJECTIVE To examine mortality risk factors in adult asthma. METHODS In a prospective cohort study of 865 adults with severe asthma in a closed-panel managed care organization, we used structured interviews to evaluate baseline sociodemographics, asthma history, and health status. Patients were followed up until death or the end of the study (mean, 2 years). We used Cox proportional hazards regression to evaluate the impact of sociodemographics, cigarette smoking, and validated measures of perceived asthma control, physical health status, and severity of asthma on the risk of death. RESULTS We confirmed 123 deaths (mortality rate, 6.7 per 100 person-years). In an analysis adjusted for sociodemographics and tobacco history, higher severity-of-asthma scores (hazard ratio [HR], 1.11 per 0.5-SD increase in severity-of-asthma score; 95% confidence interval [CI], 1.01-1.23) and lower perceived asthma control scores (HR, 0.91 per 0.5-SD increase in perceived asthma control score; 95% CI, 0.83-0.99) were each associated with risk of all-cause mortality. In the same adjusted analysis, African American race was not associated with increased mortality risk relative to white race (HR, 0.64; 95% CI, 0.36-1.14). CONCLUSIONS In a large managed care organization in which access to care is unlikely to vary widely, greater severity-of-asthma scores and poorer perceived asthma control scores are each associated with increased mortality risk in adults with severe asthma, but African American patients are not at increased risk for death relative to white patients.


BMJ | 2015

Association of hip pain with radiographic evidence of hip osteoarthritis: diagnostic test study.

Chan Kim; Michael C. Nevitt; Jingbo Niu; M. Clancy; Nancy E. Lane; Thomas M. Link; Steven C. Vlad; Irina Tolstykh; Pia M. Jungmann; David T. Felson; Ali Guermazi

Study question Is there concordance between hip pain and radiographic hip osteoarthritis? Methods In this diagnostic test study, pelvic radiographs were assessed for hip osteoarthritis in two cohorts: the Framingham Osteoarthritis Study (community of Framingham, Massachusetts) and the Osteoarthritis Initiative (a multicenter longitudinal cohort study of osteoarthritis in the United States). Using visual representation of the hip joint, participants reported whether they had hip pain on most days and the location of the pain: anterior, groin, lateral, buttocks, or low back. In the Framingham study, participants with hip pain were also examined for hip pain with internal rotation. The authors analysed the agreement between radiographic hip osteoarthritis and hip pain, and for those with hip pain suggestive of hip osteoarthritis they calculated the sensitivity, specificity, positive predictive value, and negative predictive value of radiographs as the diagnostic test. Study answer and limitations In the Framingham study (n=946), only 15.6% of hips in patients with frequent hip pain showed radiographic evidence of hip osteoarthritis, and 20.7% of hips with radiographic hip osteoarthritis were frequently painful. The sensitivity of radiographic hip osteoarthritis for hip pain localised to the groin was 36.7%, specificity 90.5%, positive predictive value 6.0%, and negative predictive value 98.9%. Results did not differ much for hip pain at other locations or for painful internal rotation. In the Osteoarthritis Initiative study (n=4366), only 9.1% of hips in patients with frequent pain showed radiographic hip osteoarthritis, and 23.8% of hips with radiographic hip osteoarthritis were frequently painful. The sensitivity of definite radiographic hip osteoarthritis for hip pain localised to the groin was 16.5%, specificity 94.0%, positive predictive value 7.1%, and negative predictive value 97.6%. Results also did not differ much for hip pain at other locations. What this study adds Hip pain was not present in many hips with radiographic osteoarthritis, and many hips with pain did not show radiographic hip osteoarthritis. Most older participants with a high suspicion for clinical hip osteoarthritis (groin or anterior pain and/or painful internal rotation) did not have radiographic hip osteoarthritis, suggesting that in many cases, hip osteoarthritis might be missed if diagnosticians relied solely on hip radiographs. Funding, competing interests, data sharing See the full paper on thebmj.com for funding. The authors have no competing interests. Additional data are available from [email protected].

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Cora E. Lewis

University of Alabama at Birmingham

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J.A. Lynch

University of California

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Nancy E. Lane

University of California

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Paul D. Blanc

University of California

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