Banca de DEFESA: BRUNA SILVA OLIVEIRA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : BRUNA SILVA OLIVEIRA
DATA : 25/11/2016
HORA: 14:00
LOCAL: Auditório do Departamento de Fisioterapia
TÍTULO:

Telomere length and lifecourse: relations with chronic conditions, inflammatory biomarkers and physical performance in community-dwelling older women

PALAVRAS-CHAVES:

telomero; aging; epidemiology; gait; education; inflammation.

PÁGINAS: 122
GRANDE ÁREA: Ciências da Saúde
ÁREA: Fisioterapia e Terapia Ocupacional
RESUMO:

Introduction: telomere length (TL) has been suggested as a possible biomarcardor of cellular aging because occurs physiological and progressive TL shortening with cell replication and aging. In addition, TL dysfunction is also favored by exposure to oxidative stress, inflammation and after chronic psychosocial stress. Studies have shown associations between TL length and life course adversities, cardiovascular disease, cancer, stroke, obesity, depression and poor physical performance. However, there is lack of knowledge in specific and particular populations such as older women in Northeastern Brazil. Whereas greater exposure to chronic stress and poor socioeconomic conditions represent major impact on the individual health status, and such as Rio Grande do Norte (RN) belongs to less socioeconomically favored Brazil region, especially in relation to education level, studies on biomarkers and life course in this population may help to understand the biological factors related to health hazards. Objectives: 1) to explore evidence on associations between chronic stress in life course and TL length through systematic review; 2) to analyze associations between TL length and childhood adversities (social and economic) in older women with different education levels; 3) to assess whether TL length is related to chronic diseases and altered blood biomarkers in older women; and 4) to verify whether shorter telomeres are associated with poor physical performance and more self-reported functional limitations. Methods: A systematic review was developed following the protocol published in 2014. In parallel, we developed a cross-sectional study with women sample (n = 106) aged 64-74 years and living in Natal, RN. Data were collected from May 2014 to March 2015. The relative TL length from peripheral blood leukocytes was measured by qPCR in real time in 83 women with different educational levels: less than secondary education (n = 42) and secondary or more education (n = 41). The questionnaire included sociodemographic information, childhood adversity experiences, anthropometric measures, self-report health, cognitive function, lifestyle, chronic conditions, functional limitations and physical performance (short physical performance battery, gait speed, chair test, and handgrip strength). It was also collected biochemical variables, including inflammatory biomarkers (interleukin-6 and C-reactive protein). Data analysis was performed using SPSS version 20, it was considered p <0.05, and 95% confidence intervals. The Kolmogorov–Smirnov test was used to check data normality. Since T/S ratio measures were highly skewed, the log transformed values was performed for subsequent analysis. To compare means and frequencies of variables between educational groups was used Student’s t test or chi-square tests. Spline multiple linear regression models were performed for association between TL and childhood adversities adjusted by potential confounding factors (age and parental alcohol abuse). To check independent associations between TL length and biochemical variables, and physical performance variables were performed linear regression models adjusted by the following factors: age, education and childhood adversity experiences. Results: the systematic review results were reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Eighteen studies published up to May 1, 2015 investigated the association between chronic social stress, characterized by poverty, exposure to violence and caregiving and TL length. In general, individuals exposed to chronic stress had shorter telomeres compared to individuals not exposed to adversities.The cross-sectional study showed that older women with low education had longer TL than the high education group (2.8 ± 0.9 and 2.0 ± 0.9, respectively; p = 0.0001). Women with less than secondary education had been exposed to more childhood adversities, and among them, those experiencing two or more adversities had longer TL than women exposed to ≤1 adversity (p = 0.03); among women with high education, this difference was not significant (p = 0.49). In analyses adjusted by age, education and parental alcohol abuse, the linear trend of higher TL with increasing adversities was confirmed (p = 0.02), and the mean difference in TL length between educational groups remained significant (p = 0.002). No difference was observed between educational groups regarding the biochemical variables (cholesterol, triglycerides, glycated hemoglobin, c-reactive protein and interleukin-6) (p > 0.05). Chronic conditions, anthropometric measures, cardiovascular risk factors and inflammatory markers were not associated with TL length, even after adjusting by age, education and childhood adversities (p> 0.05). Likewise, TL length was not related to variables used to assess physical performance and functional capacity (p> 0.05), nor after adjustment for age, educational level and adverse childhood experiences. Conclusions: The unexpected positive relationship between low education and adverse childhood experiences with TL suggests that our sample who has survived harsh living conditions prevailing in Northeast Brazil, and these women have the longest TL of their birth. The lack of relationship between TL length and chronic diseases, cardiovascular risk, inflammation and physical performance gave no support to the hypothesis that TL is a good biomarker of aging in our population.

MEMBROS DA BANCA:
Externo ao Programa - 1195933 - ANA CAROLINA PATRICIO DE ALBUQUERQUE SOUSA
Externo à Instituição - DANIELE SIRINEU PEREIRA - UNIFAL-MG
Externo à Instituição - FLORENCIA MARIA BARBE-TUANA - UFRGS
Externo ao Programa - 6346130 - MARIA BERNARDETE CORDEIRO DE SOUSA
Presidente - 350637 - RICARDO OLIVEIRA GUERRA